TY - JOUR TI - Adsorption of p-cresol on granular activated carbon AU - Das, L. AU - Kolar, P. AU - Osborne, J.A. AU - Classen, J.J. T2 - Agricultural Engineering Institute: CIGR Journal DA - 2012/// PY - 2012/// VL - 14 IS - 4 SP - 37–49 ER - TY - CHAP TI - Agricultural Waste Management Systems and Software Tools AU - Classen, J.J. AU - Lal, Harbans T2 - Waste Management - An Integrated Vision A2 - Marmolejo Rebellon, uis Fernando AB - As the demand for animal products such a milk, meat, etc. has increased, producers have found ways to increase productivity and decrease the unit cost of production. Fossil fuels, inorganic fertilizer, pesticides, improved genetics of production species, better management techniques, and mechanization allowed productivity to increase to meet these demands. This has also meant concentration of more animals at each location. Confining some types of animals to houses or barns through all or most of their life cycle protects them from the weather and from predators and facilitates feeding, animal movement, and materials handling. Producers have benefited from economies of scale and product uniformity to provide the consumer with low-cost, high-quality meat and animal products. PY - 2012/10/26/ DO - 10.5772/50484 PB - InTech UR - http://dx.doi.org/10.5772/50484 ER - TY - CONF TI - Safe Feedstock Handling For Vermiculture Operations AU - Simmons, O.D., III T2 - North Carolina State University 13th Vermiculture Conference C2 - 2012/11/5/ CY - Chapel Hill, NC DA - 2012/11/5/ PY - 2012/11/5/ ER - TY - SOUND TI - Viruses in Fresh Produce: What Every Producer Should Know! AU - Simmons, O.D., III AU - Jaykus, L.A. DA - 2012/11/27/ PY - 2012/11/27/ ER - TY - CONF TI - Control of Human Virus Contamination in Molluscan Shellfish: Where we are and where we need to be? AU - Simmons, O.D., III AU - Jaykus, L.A. T2 - Intrastate Shellfish Sanitation Conference and South Atlantic Shellfish Conference C2 - 2012/4// CY - Savannah, GA DA - 2012/4// PY - 2012/4// ER - TY - CONF TI - Irrigation Water Concerns and Recommendations for Fruit and Vegetable Growers AU - Gunter, C. AU - Barrier, H. AU - Simmons, O.D., III T2 - Axiall/PPG Industrial Specialists Conference C2 - 2012/// CY - Charlotte, NC DA - 2012/// PY - 2012/// ER - TY - SOUND TI - Farm Commodity Recall Workshop AU - Chapman, B. AU - Gunter, C. AU - Simmons, O.D., III DA - 2012/8/28/ PY - 2012/8/28/ ER - TY - CONF TI - The Role of Water for Maintaining the Microbial Quality of Fresh Produce During Production" AU - Simmons, O.D., III T2 - North Carolina State University Fulbright Scholars Symposium C2 - 2012/// CY - Raleigh, NC DA - 2012/// PY - 2012/// ER - TY - CONF TI - Measurement and Analysis of Temporal and Spatial Variations of Bioaerosol Concentrations in a High-rise Egg Production House AU - Hu, D. AU - Wang-Li, L. AU - O.D. Simmons, O.D., III AU - Osborne, J.A. AU - Classen, J.J. T2 - Air and Waste Management Association Symposium on Air Quality Measurement Methods and Technology C2 - 2012/4/24/ CY - Durham, North Carolina DA - 2012/4/24/ PY - 2012/4/24/ ER - TY - CONF TI - Temporal and Spatial Variations of Bioaerosols Emitted from an Egg Production Facility in Southeast U.S.: Part III – Size Distributions and Viable Versus Non-Viable AU - Hu, D. AU - Wang-Li, L. AU - Simmons, O.D., III AU - Osborne, J.A. AU - Classen, J.J. T2 - American Society of Agricultural and Biological Engineers Annual Meeting C2 - 2012/7/29/ CY - Dallas, Texas DA - 2012/7/29/ PY - 2012/7/29/ ER - TY - CONF TI - Temporal and Spatial Variations of Bioaerosols Emitted from an Egg Production Facility in Southeast U.S Part II - Concentrations in the Vicinity AU - Hu, D. AU - Wang-Li, L. AU - Simmons, O.D., III AU - Osborne, J.A. AU - Classen, J.J. T2 - American Society of Agricultural and Biological Engineers Annual Meeting C2 - 2012/7/29/ CY - Dallas, Texas DA - 2012/7/29/ PY - 2012/7/29/ ER - TY - CONF TI - Experimental investigation of failure mechanisms of expanded polystryrene block geofoam slope system under seepage AU - Akay, O. AU - Özer, A.T. AU - Fox, G.A. T2 - 5th European Geosynthetics Congress C2 - 2012/// C3 - EuroGeo 5 : proceedings of the fifth Geosynthetics Congress, Valencia, Spain, 16-19 September 2012 CY - Valencia, Spain DA - 2012/// PY - 2012/9/16/ PB - R.B. Servicios Editoriales SN - 9788469546888 ER - TY - CONF TI - Enhancing engagement in assessment through a systematic faculty development program AU - Penn, J. AU - Fox, G.A. T2 - NCA Higher Learning Commission Annual Conference C2 - 2012/// CY - Chicago, IL DA - 2012/// PY - 2012/3/30/ ER - TY - JOUR TI - A river runs through ASABE AU - Fox, G.A. T2 - Resource DA - 2012/// PY - 2012/// VL - 19 IS - 2 SP - SP2 ER - TY - JOUR TI - Auger Reactor Gasification of Algal Blooms Produced In a Waste Water Treatment Facility AU - Sharara, Mahmoud A AU - Sadaka, Samy S T2 - 2012 Dallas, Texas, July 29 - August 1, 2012 AB - Aquatic biomass; i.e., algae have been successfully incorporated in wastewater treatment as nutrients strippers. Low-maintenance algal communities; i.e., wild species, can be a cheap and effective sequestration strategy. Few studies have investigated the quality of wastewater treatment algae as a potential feedstock for thermochemical conversion in atmospheric gasification. This study is a preliminary investigation of the gasification of wastewater treatment algae as means to produce renewable gaseous fuel streams, and also to condense minerals and micro- nutrients into easily managed char using an auger gasifier. Three temperature conditions were investigated in this study; 760, 860 and 960 C. Temperatures were found to increase the concentration of CO, and H2 in producer gas from 12.8% and 4.7% (vol.) at 760 C to 16.9% and 11.4% at 960 C, respectively. On the other hand, concentration of CO2 in producer gas decreased from 14.0% to 11.6% (vol.) with the increase in temperatures from 760 C to 960 C, respectively. Tar yields ranged between 15% and 16.6%, whereas char yields fell between 46% and 51% due to the significantly high ash content of raw algae; >40% dry-basis. The high ash content in char, however, might bolster gasification as a minerals concentration step which would facilitate transportation, and re-use of these minerals. Future studies will further investigate the thermodynamic performance of auger gasification on aquatic biomass. Also, fate of various minerals after this process will be investigated in future research. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41851 ER - TY - JOUR TI - Apoptotic susceptibility to DNA damage of pluripotent stem cells facilitates pharmacologic purging of teratoma risk AU - Smith, A.J. AU - Nelson, N.G. AU - Oommen, S. AU - Hartjes, K.A. AU - Folmes, C.D. AU - Terzic, A. AU - Nelson, T.J. T2 - Stem Cells Translational Medicine AB - Pluripotent stem cells have been the focus of bioengineering efforts designed to generate regenerative products, yet harnessing therapeutic capacity while minimizing risk of dysregulated growth remains a challenge. The risk of residual undifferentiated stem cells within a differentiated progenitor population requires a targeted approach to eliminate contaminating cells prior to delivery. In this study we aimed to validate a toxicity strategy that could selectively purge pluripotent stem cells in response to DNA damage and avoid risk of uncontrolled cell growth upon transplantation. Compared with somatic cell types, embryonic stem cells and induced pluripotent stem cells displayed hypersensitivity to apoptotic induction by genotoxic agents. Notably, hypersensitivity in pluripotent stem cells was stage-specific and consistently lost upon in vitro differentiation, with the mean half-maximal inhibitory concentration increasing nearly 2 orders of magnitude with tissue specification. Quantitative polymerase chain reaction and Western blotting demonstrated that the innate response was mediated through upregulation of the BH3-only protein Puma in both natural and induced pluripotent stem cells. Pretreatment with genotoxic etoposide purged hypersensitive pluripotent stem cells to yield a progenitor population refractory to teratoma formation upon transplantation. Collectively, this study exploits a hypersensitive apoptotic response to DNA damage within pluripotent stem cells to decrease risk of dysregulated growth and augment the safety profile of transplant-ready, bioengineered progenitor cells. DA - 2012/// PY - 2012/// DO - 10.5966/sctm.2012-0066 VL - 1 IS - 10 SP - 709-718 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84876510977&partnerID=MN8TOARS KW - Apoptosis KW - Stem cells KW - Pluripotent stem cells KW - Stem cell transplantation KW - Tumor cell purging ER - TY - JOUR TI - Improving woody, early successional habitat patches to benefit shrubland birds AU - Shake, C. AU - Moorman, C. AU - Burchell, M.R. T2 - The Upland Gazette DA - 2012/// PY - 2012/// VL - 17 IS - 2 SP - 9–10 ER - TY - RPRT TI - Improving woody, early successional habitat patches for shrubland birds AU - Shake, C. AU - Moorman, C. AU - Burchell, M.R. A3 - USDA NRCS Field Office DA - 2012/// PY - 2012/// PB - USDA NRCS Field Office ER - TY - RPRT TI - Dune infiltration systems for reducing stormwater discharge into coastal waters AU - Burchell, M.R. AU - Hunt, W.F. AU - Price, W.D. A3 - North Carolina State University Biological & Agricultural Engineering and North Carolina Cooperative Extension DA - 2012/// PY - 2012/// M1 - EBAE-275-12 PB - North Carolina State University Biological & Agricultural Engineering and North Carolina Cooperative Extension SN - EBAE-275-12 ER - TY - RPRT TI - Stormwater wetlands for golf courses AU - Bass, K.L. AU - Burchell, M.R. AU - Evans, R.O. AU - Hunt, W.F. AU - Line, D. AU - Seth-Carley, D. A3 - North Carolina Cooperative Extension Publication DA - 2012/// PY - 2012/// M1 - AG-765 M3 - NC State Extension Publications PB - North Carolina Cooperative Extension Publication SN - AG-765 ER - TY - RPRT TI - Hydrologic Impacts of Rerouting Pumped Agricultural Drainage Water Through a Historical and Restored Wetland System as Part of an Innovative Integrated Water Management System in Hyde County, NC AU - Burchell, M.R. AU - Bass, K.L. AU - Chescheir, G.M. AU - Youssef, M. AU - Birgand, F. AU - Evans, R.O. A3 - North Carolina Community Foundation DA - 2012/10// PY - 2012/10// M3 - Final Report PB - North Carolina Community Foundation ER - TY - JOUR TI - Sodium hydroxide pretreatment of genetically modified switchgrass for improved enzymatic release of sugars AU - Wang, Ziyu AU - Li, Ruyu AU - Xu, Jiele AU - Marita, Jane M. AU - Hatfield, Ronald D. AU - Qu, Rongda AU - Cheng, Jay J. T2 - Bioresource Technology AB - Overcoming biomass recalcitrance to bioconversion is crucial for cellulosic biofuels commercialization. In this study, Alamo switchgrass (Panicum virgatum L.) was genetically transformed to suppress the expression of 4-coumarate-CoA ligase (4CL). The transgenic plants were determined to have lignin content reductions of up to 5.8%. The ratios of acid soluble lignin (ASL) to acid insoluble lignin (AIL) and syringyl/guaiacyl (S/G) in transgenic plants were 21.4–64.3% and 11.8–164.5%, respectively, higher than those of conventional biomass. Both conventional and transgenic plants were pretreated with 0.5%, 1%, and 2% (w/v) NaOH for 15, 30, and 60 min at 121 °C, followed by enzymatic hydrolysis with commercial cellulases and xylanases. At the optimal conditions, the glucan and xylan conversion efficiency in the best transgenic plants were 16% and 18% higher than the conventional plant, respectively. The results show that down-regulation of 4CL gene promoted enzymatic hydrolysis of plant cell walls following a mild alkali pretreatment. DA - 2012/4// PY - 2012/4// DO - 10.1016/j.biortech.2012.01.097 VL - 110 SP - 364-370 J2 - Bioresource Technology LA - en OP - SN - 0960-8524 UR - http://dx.doi.org/10.1016/j.biortech.2012.01.097 DB - Crossref KW - Genetic modification KW - Lignin KW - Switchgrass KW - Sodium hydroxide pretreatment KW - Sugar ER - TY - JOUR TI - Growing Spirodela polyrrhiza in Swine Wastewater for the Production of Animal Feed and Fuel Ethanol: A Pilot Study AU - Xu, Jiele AU - Cheng, Jay J. AU - Stomp, Anne-M. T2 - CLEAN - Soil, Air, Water AB - Abstract To evaluate the performance of Spirodela polyrrhiza grown in swine wastewater for protein and starch production under field conditions, a pilot‐scale duckweed culture pond was installed at Barham Farm, Zebulon, North Carolina and operated from May to November 2010. The anaerobically treated swine wastewater was fed to the duckweed pond intermittently to provide nutrients for the growth of duckweed, and the duckweed biomass was harvested regularly from the pond and prepared as a protein‐ or starch‐rich feedstock for the production of animal feed or fuel ethanol. Over the experimental period, the duckweed pond produced protein and starch at rates of 2.68 and 1.88 g m −2 day −1 , respectively. During the same time, NH 4 –N and o ‐PO 4 –P in the wastewater were, respectively, removed at rates of 92.9 and 2.90 mmol m −2 day −1 . DA - 2012/5/18/ PY - 2012/5/18/ DO - 10.1002/clen.201100108 VL - 40 IS - 7 SP - 760-765 J2 - Clean Soil Air Water LA - en OP - SN - 1863-0650 UR - http://dx.doi.org/10.1002/clen.201100108 DB - Crossref KW - Duckweed KW - Nutrients KW - Protein KW - Starch KW - Swine wastewater ER - TY - CONF TI - Rainwater Harvesting: Integrating Water Conservation and Stormwater Management through Innovative Technologies AU - DeBusk, K. AU - Hunt, W. AU - Quigley, M. AU - Jeray, J. AU - Bedig, A. T2 - World Environmental And Water Resources Congress 2012 AB - Recent droughts, population increases, and predicted climate change have emphasized the fragility of water resources and the need for water conservation within the state of North Carolina, USA. The necessity of stormwater management is another ever-present reality for the state due to increases in urban development and resulting declines in water quality. Rainwater harvesting (RWH) systems are unique in their ability to provide an alternate source of water and serve as detention/retention for roof runoff that would otherwise be discharged to the stormwater network. This study focuses on two RWH systems, each of which employ an innovative method of increasing the stormwater management potential of the system: an active release mechanism and a passive release mechanism. The purpose of this study is to document how well RWH systems serve as both water conservation practices and stormwater management practices when equipped with these innovative technologies. C2 - 2012/5/17/ C3 - World Environmental and Water Resources Congress 2012 DA - 2012/5/17/ DO - 10.1061/9780784412312.372 PB - American Society of Civil Engineers SN - 9780784412312 UR - http://dx.doi.org/10.1061/9780784412312.372 DB - Crossref ER - TY - CONF TI - Developing a Carbon Footprint of Urban Stormwater Infrastructure AU - Moore, Trisha L. C. AU - Hunt, William F. T2 - World Environmental And Water Resources Congress 2012 AB - Concerns over global climate change have spurred interest in accounting for carbon emissions from human activities. Most of this effort has focused on emissions from vehicles and energy use within buildings. However, relatively little is known about how the urban landscape, and particularly stormwater management, contributes to the carbon footprint of urban areas. The objective of this work was to present a method by which carbon emissions attributable to the construction and maintenance of stormwater control measures (SCMs) and conveyances could be predicted. This method was then applied to present a comparison of the carbon footprint of eight common SCMs and three conveyance practices. The carbon embodied in construction materials represented a prominent part of the carbon footprint for green roofs, permeable pavement, sand filters, rainwater harvesting systems, and reinforced concrete pipes while material transport and construction dominated that of bioretention systems, ponds, wetlands, level spreader-grassed filter strips and concrete-lined swales. Despite accounting for sequestration by vegetation in these systems, only stormwater wetlands and grassed swales were predicted to store more carbon than was released through construction and maintenance. C2 - 2012/5/17/ C3 - World Environmental and Water Resources Congress 2012 DA - 2012/5/17/ DO - 10.1061/9780784412312.089 PB - American Society of Civil Engineers SN - 9780784412312 UR - http://dx.doi.org/10.1061/9780784412312.089 DB - Crossref ER - TY - CONF TI - Water Quality Benefits of Harvesting Rooftop Runoff AU - DeBusk, K. M. AU - Hunt, W. F. T2 - World Environmental And Water Resources Congress 2012 AB - It is well documented that runoff from roof surfaces carries a wide variety of pollutants including sediment, heavy metals, nutrients and bacteria. Collecting and storing this roof runoff via rainwater harvesting systems could provide water quality benefits due to physical and chemical processes that occur within the storage tank. Four fire stations in Raleigh, North Carolina, USA, were equipped with rainwater harvesting systems. Samples of roof runoff were collected after each storm to determine pre-cistern water quality characteristics. Samples were also collected at the extraction spigot for the system. All samples were analyzed for total suspended solids (TSS), total nitrogen (TN), total Kjeldahl nitrogen (TKN), nitrite (NO2)+nitrate (NO3), ammonia (NH3), and total phosphorus (TP). Water quality data will be analyzed to determine if storing water within a cistern has a significant effect on pollutant concentrations. Water usage data collected during the study period will be compiled and pollutant loads will be computed. C2 - 2012/5/17/ C3 - World Environmental and Water Resources Congress 2012 DA - 2012/5/17/ DO - 10.1061/9780784412312.063 PB - American Society of Civil Engineers SN - 9780784412312 UR - http://dx.doi.org/10.1061/9780784412312.063 DB - Crossref ER - TY - CONF TI - Stormwater Monitoring of Innovative Street Retrofits in Urban Wilmington, NC AU - Page, J. L. AU - Winston, R. J. AU - Hunt, W. F. T2 - World Environmental And Water Resources Congress 2012 AB - Many urban watersheds suffer from degraded water quality caused by stormwater runoff from rooftops, parking lots, streets and other impervious surfaces. Low Impact Development (LID) is a design approach that utilizes stormwater control measures (SCMs) to maintain and restore the natural hydrologic features of a watershed by promoting infiltration of runoff into the soil, treating runoff at its source, and minimizing impervious surface coverage. Peer-reviewed literature is lacking on the application of bioretention, permeable pavement and tree filter boxes to treat urban street runoff on a catchment-scale. A pre- and post-retrofit study has been designed to evaluate the impacts of catchment-scale retrofits on hydrology and water quality. The project will be implemented on two midblock street sections in a residential neighborhood in Wilmington, North Carolina. It includes construction of permeable pavement parking stalls, tree filter boxes and bioretention areas that extend into the street right-of-way, thereby reducing impervious surface area and increasing pedestrian safety. Runoff volumes and pollutant concentrations of bacteria, heavy metals, nutrients, polycyclic aromatic hydrocarbons (PAHs) and suspended solids were monitored from June 2011 to October 2011 at the retrofit site and an additional control site located four blocks to the West. Preliminary results from the pre-retrofit monitoring show mean concentrations of total Kjeldahl nitrogen (TKN) from the control and retrofit watersheds were 2.02 mg/L and 1.52 mg/L, respectively. Total phosphorus (TP) mean concentrations from the control and retrofit watersheds were similar at 0.31 mg/L and 0.29 mg/L, respectively. TKN and TP concentrations observed in this study at both monitoring sites were less than TKN and TP mean concentrations from National Urban Runoff Program (NURP) urban sites and NURP streets. Copper (Cu), lead (Pb) and zinc (Zn) mean concentrations from the control and retrofit watersheds were less than those reported from NURP urban sites and NURP streets. Total nitrogen (TN) and TP yearly loads were greater in the control watershed, which may be due to the greater fraction of impervious surface coverage and fertilizer use in the control watershed. The results and conclusions from this study will help refine street retrofit design standards to meet runoff volume reduction, peak discharge mitigation and water quality goals while increasing pedestrian safety and improving aesthetics in the neighborhood. C2 - 2012/5/17/ C3 - World Environmental and Water Resources Congress 2012 DA - 2012/5/17/ DO - 10.1061/9780784412312.056 PB - American Society of Civil Engineers SN - 9780784412312 UR - http://dx.doi.org/10.1061/9780784412312.056 DB - Crossref ER - TY - CONF TI - Evaluation of Bridge Deck Runoff and Its Effects on In-Stream Health AU - Winston, R. J. AU - Hunt, W. F. AU - Lauffer, M. S. T2 - World Environmental And Water Resources Congress 2012 AB - Bridges typically drain through scuppers directly to streams or estuaries below, potentially resulting in degradation of surface water quality. The North Carolina General Assembly enacted Session Law 2008-107 in July 2008, which required the N.C. Department of Transportation to study the effects of stormwater runoff from bridges over waterways. The resulting study characterized 15 bridge decks across three ecoregions of N.C. for runoff quality and quantity. Monitoring sites were located across the Piedmont, Coastal Plain, and Mountain ecoregions of NC and had differences in wearing surface, annual average daily traffic, rural vs. urban watershed, bridge deck surface area, and stream drainage areas. The goals included characterizing bridge deck pollutants of concern and determining the effects of bridge deck runoff on in-stream health. Runoff water quality and quantity were measured at 15 bridges, instream water quality and quantity at 4 sites, streambed sediment quality at 30 sites, bioassay tests at 13 sites, and biosurvey tests at 15 sites. Median EMCs for TSS, TN, TP, total petroleum hydrocarbons (TPH), total copper, total lead, and total zinc were 39 mg/L, 0.97 mg/L, 0.17 mg/L, 3.1 mg/L, 9.6 μg/L, 5.3 μg/L, and 66 μg/L, respectively. Twenty-two parameters of concern, those with maximum observed concentrations above the strictest available state or federal threshold, were identified, including: pH, TSS, TN, TP, five total heavy metals, five dissolved heavy metals, and seven semi-volatiles. The best predictor of pollutant concentration was the land-use type of the watershed (urban vs. rural). Pollutant concentrations and loads observed from bridge decks were similar to or less than those from other highway and urban runoff studies. Pollutant loads from the bridge decks for all analytes studied were less than 0.25% of the pollutant load contributed by the whole watershed, since the ratio of bridge deck area to watershed area was always small (<2%). At the 30 bridge deck sites studied for stream bed sediment quality (organic and inorganic pollutants), no significant difference was observed between upstream vs. downstream sediment quality or between downstream sediment quality from direct vs. no-direct discharge bridges. Composite samples from bridge deck stormwater runoff, in-stream stormflow, and in-stream baseflow were utilized in Ceriodaphnia dubia bioassay tests. All samples were tested at 100% concentration, and bridge deck runoff samples also were tested at dilutions of 50%, 25%, 12.5%, and 6.25%. Of 25 bridge deck runoff samples, 3 exhibited toxicity at 100% concentration due to significantly reduced reproduction in the test organism. Potential reasons for this toxicity included elevated conductivity in one sample and low hardness and pH in another sample. No toxicity was observed at lower dilutions of the bridge deck runoff, indicating the potential for toxicity would be attenuated at instream concentrations. Of 20 instream stormflow and baseflow samples, no toxicity was observed. Instream mixing and large catchment area relative to bridge deck footprints (as much as 106 larger) resulted in substantial dilution of bridge deck runoff at these sites. Biosurveys (benthic macroinvertebrate sampling) were conducted upstream and downstream of 12 bridges. Samples were obtained using Qual 5 methodology, and bioclassification was determined using the EPT and N.C. biotic index metrics. One study site had a biotic index change large enough to suggest a decline in water quality downstream of the bridge deck. However, bioclassification rating was never different between upstream and downstream sampling areas. When the data were evaluated en masse, runoff concentrations and pollutant loads were similar to those from other urban and transportation runoff studies. Attempts to tie stormwater runoff to reduced in-stream health (sediment quality, benthic health, aquatic toxicity) were unsuccessful; this suggests that bridge deck runoff does not have widespread effects on receiving water quality. C2 - 2012/5/17/ C3 - World Environmental and Water Resources Congress 2012 DA - 2012/5/17/ DO - 10.1061/9780784412312.041 PB - American Society of Civil Engineers SN - 9780784412312 UR - http://dx.doi.org/10.1061/9780784412312.041 DB - Crossref ER - TY - CONF TI - Enhancement of Exfiltration and Thermal Load Reduction from Permeable Pavement with Internal Water Storage AU - Wardynski, B. J. AU - Winston, R. J. AU - Hunt, W. F. T2 - World Environmental And Water Resources Congress 2012 AB - Stream temperature spikes associated with urban runoff can have negative ecological impacts on coldwater streams. Several local and federal regulations now specifically target urban runoff temperature, which creates a need for practices that reduce thermal export from a catchment. Several stormwater control measures (SCMs) have been shown to buffer thermal impacts to waterways by passing water through cooler subsurface media or by reducing overall runoff volume. Because it performs these functions, permeable pavement is a promising practice for thermal mitigation. A parking lot was constructed with permeable interlocking concrete pavers (PICP) the Mountain region of North Carolina to investigate the thermal behavior of this SCM. The 239-m2 lot was divided into three cells with varying depths and drainage configurations to also test the hydrologic and thermal effects of including internal water storage (IWS) in permeable pavement. After one year of monitoring, results showed substantial stormwater volume reductions from all permeable pavement configurations, with the most pronounced reductions (99.6% and 100%) experienced in the shallow and deep IWS cells, respectively. Consequently, thermal load export from the site was reduced by a comparable amount. Median and maximum stormwater effluent temperatures from the conventionally drained cell (78% runoff reduction) exceeded the critical trout threshold temperature of 21°C, however, outflow only occurred during 8 storm events (out of the 54 recorded). Temperature differentials between the top and bottom the PICP profiles suggest that buffering of extreme runoff temperatures can occur. Additionally, the subsoil interface never reached freezing temperatures during the winter season. These results credit the use of PICP where thermal impact to streams is of concern, particularly with the incorporation of IWS. C2 - 2012/5/17/ C3 - World Environmental and Water Resources Congress 2012 DA - 2012/5/17/ DO - 10.1061/9780784412312.038 PB - American Society of Civil Engineers SN - 9780784412312 UR - http://dx.doi.org/10.1061/9780784412312.038 DB - Crossref ER - TY - CONF TI - Can Roadside Vegetation and Soil Act As a Carbon Sink? AU - Bouchard, N. B. AU - Hunt, W. F. AU - Moore, T. L. C. AU - Winston, R. J. T2 - World Environmental And Water Resources Congress 2012 AB - Stormwater Control Measures (SCMs) have long been understood to clean and treat runoff, but these systems may provide additional ecosystem benefits not currently quantified. The main goal of this project was to determine carbon (C) sequestration potential of common roadside SCMs within the Piedmont and Coastal Plain eco-regions of North Carolina. Along highways vegetated filter strips (VFS) and vegetated swales (VS) or wetland swales (WS) work in conjunction to trap sediment bound pollutants associated with runoff from the roadway. The VFS/VS systems work well in the roadside environment since they are linear and easily border the roadway, additionally they require little maintenance. Roadside VFS/VS systems (ranging in age from 1 to 38 years) within two physiographic regions of NC were sampled to evaluate C accumulation within the soil. Based upon ArcGIS analysis, each site was identified and systematically sampled from May to July 2011. Twenty VFS/VS sites were established in the Piedmont and Coastal Plain region, respectively. An additional 20 wetland swale sites were also sampled in the Coastal Plain region, which allows a comparison between the dry swales and the WSs within the Coastal Plain. Age, regional (i.e. Piedmont versus Coastal Plain), position (sampling distance from roadway), depth, and swale characteristics (i.e. WS versus VS) effects upon C accumulation are being examined in this study. C2 - 2012/5/17/ C3 - World Environmental and Water Resources Congress 2012 DA - 2012/5/17/ DO - 10.1061/9780784412312.031 PB - American Society of Civil Engineers SN - 9780784412312 UR - http://dx.doi.org/10.1061/9780784412312.031 DB - Crossref ER - TY - CONF TI - Evaluation of Floating Wetland Islands As a Retrofit to Existing Stormwater Detention Basins AU - Winston, R. J. AU - Hunt, W. F. AU - Kennedy, S. G. T2 - World Environmental And Water Resources Congress 2012 AB - Since the passage of the Clean Water Act, wet detention ponds have been installed across the United States primarily for peak flow mitigation and sediment reduction. However, there are surprisingly minimal data on water quality benefits of these systems. Additionally, tremendous retrofitting pressure is likely to accompany state of North Carolina-implemented watershed rules associated with the Jordan Lake and Fall Lake reservoirs. Municipalities in these watersheds will be required to meet nutrient load reduction targets, necessitating urban stormwater practice retrofits for existing development. Therefore, it is imperative for many cities in central North Carolina to identify cost effective retrofits. One potential retrofit, floating wetland islands, is particularly attractive because they (1) do not require earth moving, (2) eliminate the need for additional land to be dedicated to treatment, and (3) will not detract from the required storage volume required for wet ponds (because they float). Two wet ponds in Durham, NC, were retrofitted with floating wetland islands. Prior to retrofit, both ponds had little to no vegetation growing inside them. After retrofit, one pond's surface area was comprised of 8% floating wetland islands and the second pond had 19% coverage. The two ponds were monitored in a non-retrofitted state from November 2008 to March 2010. Floating wetland islands were then installed in March-April 2010. After vegetation had established on the islands, monitoring recommenced in July 2010. Area-velocity meters and Manning's equation were used to take flow-proportional, composite water quality samples. Sixteen water quality samples were taken prior to the floating island retrofit, and twelve have been collected thus far post-retrofit. Initial results show that mean effluent concentrations of total nitrogen (TN) were reduced at one pond from 1.05 mg/L to 0.61 mg/L from pre- to post-retrofit. The other pond had relatively low effluent concentrations (0.41 mg/L and 0.43 mg/L) both pre- and post-retrofit. Mean TP effluent concentrations were reduced at both wet ponds from pre- to post-retrofit (0.17 mg/L to 0.12 mg/L and 0.11 mg/L to 0.05 mg/L. Additionally, TSS effluent concentrations at both ponds were modestly lower post-retrofit, presumably due to additional hydraulic resistance provided by the floating islands and their hanging roots, which have been measured to be approximately 0.6 m (2 ft). Initial results show some modest nutrient and sediment removal benefits from the addition of floating islands to stormwater detention ponds. Additional benefits which will be determined in the future include wetland vegetation root mass and potential improvements in benthic macroinvertebrate habitat. C2 - 2012/5/17/ C3 - World Environmental and Water Resources Congress 2012 DA - 2012/5/17/ DO - 10.1061/9780784412312.030 PB - American Society of Civil Engineers SN - 9780784412312 UR - http://dx.doi.org/10.1061/9780784412312.030 DB - Crossref ER - TY - JOUR TI - Effectiveness of LID for Commercial Development in North Carolina AU - Line, D. E. AU - Brown, R. A. AU - Hunt, W. F. AU - Lord, W. G. T2 - Journal of Environmental Engineering AB - The purpose of this project was to characterize runoff and pollutant export from three commercial sites: one with no storm water control measures (NoTreat), one with a wet detention basin (WetBasin), and one with low impact development (LID) measures. The sites were located in the Piedmont and Coastal Plain physiographic regions of central North Carolina. Rainfall, runoff, and pollutant concentrations were monitored at each site for more than one year by using automated rain gauges and samplers. The storm event mean concentrations (EMCs) of total kjeldahl nitrogen (TKN), nitrate+nitrite nitrogen (NOx-N), and total phosphorus (TP) in runoff were generally less than corresponding EMCs for many other urban areas in the United States. Also, EMCs were similar to those found for eight parking lots in North Carolina. Storm runoff to rainfall ratio was greatest for the NoTreat site and least for the WetBasin site, which was anticipated because the NoTreat site had no detention/storage and the WetBasin site had the greatest detention/storage. Export of TKN, ammonia nitrogen (NH3-N), TP, and total suspended solids (TSS) was lowest for the LID site, whereas export of NOx-N and TN was lowest for the WetBasin site. Although by no means definitive, the monitoring data indicated that the LID site with its multiple LID measures was more effective at reducing export for most pollutants than the WetBasin site with its wet detention basin. DA - 2012/6// PY - 2012/6// DO - 10.1061/(ASCE)EE.1943-7870.0000515 VL - 138 IS - 6 SP - 680-688 J2 - J. Environ. Eng. LA - en OP - SN - 0733-9372 1943-7870 UR - http://dx.doi.org/10.1061/(ASCE)EE.1943-7870.0000515 DB - Crossref KW - Low impact development KW - Effectiveness KW - Storm water monitoring KW - Commercial sites ER - TY - CONF TI - Probable maximum flood inundation modeling: A case study in southern Virginia C2 - 2012/// C3 - River Flow 2012 DA - 2012/// ER - TY - JOUR TI - Harvestable Nitrogen Accumulation for Five Storm Water Wetland Plant Species: Trigger for Storm Water Control Measure Maintenance? AU - Lenhart, H. A. AU - Hunt, W. F. AU - Burchell, M. R. T2 - Journal of Environmental Engineering AB - As the use of constructed storm water wetlands to treat storm water runoff becomes more frequent, strategies for maintaining or increasing their pollutant removal over time must be examined. One potential strategy is plant harvesting at the water surface to remove nutrients that would otherwise be deposited back into the wetland during senescence. This technical note presents a first look at this strategy from a storm water management perspective. Vegetation was harvested from two storm water wetlands located in Smithfield and Pactolus, North Carolina, to evaluate the ability of five wetland plant species to sequester nitrogen. Biomass samples were collected from the following species of emergent vegetation: Pontederia cordata (Pickerelweed), Saururus cernuus (Lizard Tail), Scirpus cyperinus (Wool Grass), Sagittaria latifolia (Arrowhead), and Schoenoplectus tabernaemontani (Softstem Bulrush). Samples were collected immediately prior to senescence in September and October 2007 and analyzed for nitrogen content on a percent of biomass basis. At the Pactolus wetland the Pontederia cordata, Scirpus cyperinus, and Schoenoplectus tabernaemontani biomass retained significantly (p<0.05) more nitrogen than Sagittaria latifolia and Saururus cernuus. At the Smithfield wetland, Pontederia cordata and Sagittaria latifolia biomass retained significantly more nitrogen than Scirpus cyperinus and Saururus cernuus. Wetland maturity appears to have a direct relationship to harvestable nitrogen, which could explain why the relative amount of nitrogen sequestered in Scirpus cyperinus and Sagittaria latifolia varied between the two wetlands. A positive relationship existed between the density of harvested biomass and nitrogen removal for two species. To estimate the relative amount of harvestable nitrogen, a model for estimating total nitrogen loading in Coastal Plain watersheds in North Carolina was used to compare estimated inflow nitrogen mass to that which could theoretically be harvested. The harvestable N mass was greater than 20% of inflow nitrogen on an annual basis. Storm water wetland plant harvesting as a maintenance activity has potential to supplement wetland nitrogen removal. DA - 2012/9// PY - 2012/9// DO - 10.1061/(ASCE)EE.1943-7870.0000550 VL - 138 IS - 9 SP - 972-978 J2 - J. Environ. Eng. LA - en OP - SN - 0733-9372 1943-7870 UR - http://dx.doi.org/10.1061/(ASCE)EE.1943-7870.0000550 DB - Crossref KW - Storm water control measure KW - Best management practice KW - Storm water KW - Runoff KW - Wetlands KW - Nitrogen KW - Uptake KW - Harvesting ER - TY - JOUR TI - Hydrothermal conversion of big bluestem for bio-oil production: The effect of ecotype and planting location AU - Gan, Jing AU - Yuan, Wenqiao AU - Johnson, Loretta AU - Wang, Donghai AU - Nelson, Richard AU - Zhang, Ke T2 - Bioresource Technology AB - Three ecotypes (CKS, EKS, IL) and one cultivar (KAW) of big bluestem (Andropogon gerardii) that were planted in three locations (Hays, KS; Manhattan, KS; and Carbondale, IL) were converted to bio-oil via hydrothermal conversion. Significant differences were found in the yield and elemental composition of bio-oils produced from big bluestem of different ecotypes and/or planting locations. Generally, the IL ecotype and the Carbondale, IL and Manhattan, KS planting locations gave higher bio-oil yield, which can be attributed to the higher total cellulose and hemicellulose content and/or the higher carbon but lower oxygen contents in these feedstocks. Bio-oil from the IL ecotype also had the highest carbon and lowest oxygen contents, which were not affected by the planting location. Bio-oils from big bluestem had yield, elemental composition, and chemical compounds similar to bio-oils from switchgrass and corncobs, although mass percentages of some of the compounds were slightly different. DA - 2012/7// PY - 2012/7// DO - 10.1016/j.biortech.2012.03.120 VL - 116 SP - 413-420 J2 - Bioresource Technology LA - en OP - SN - 0960-8524 UR - http://dx.doi.org/10.1016/j.biortech.2012.03.120 DB - Crossref KW - Bio-oil KW - Big bluestem KW - Hydrothermal conversion KW - Liquefaction ER - TY - JOUR TI - Culture of microalgal strains isolated from natural habitats in Thailand in various enriched media AU - Chaichalerm, Sudarat AU - Pokethitiyook, Prayad AU - Yuan, Wenqiao AU - Meetam, Metha AU - Sritong, Kamolwan AU - Pugkaew, Wanvisa AU - Kungvansaichol, Kunn AU - Kruatrachue, Maleeya AU - Damrongphol, Praneet T2 - Applied Energy AB - Six freshwater microalgal strains in the class of Chlorophyceae, including Chlorococcum humicola, Didymocystis bicellularis, Monoraphidium contortum, Oocystis parva, Sphaerocystis sp., and Scenedesmus acutus were isolated from natural habitats in Thailand. The six strains were compared for their biomass yield, lipid content, and lipid productivity in four enriched culture media in batch mode. Significant differences were found across algal strains and culture media. The best strain was found to be C. humicola, which had the highest biomass yield of 0.113 g/l/d (in Kuhl medium), the highest lipid content of 45.94% (in BG-11 medium), and the highest lipid yield of 0.033 g/l/d (in 3NBBM medium). The 3NBBM medium, which has the lowest nitrogen concentration among the four culture media, was considered the optimal culture medium for C. humicola for lipid production. The fatty acid profile of C. humicola was also found to be affected by the culture medium. More oleic acid (C18:1) but less linolenic acid (C18:3) was accumulated in BG-11 and 3NBBM than in Kuhl and N-8 media. Lipid profiles of C. humicola were comparable to palm oil in the percentage of palmitic acid and the total amount of saturated fatty acids; however, C. humicola made more poly-unsaturated fatty acids such as linoleic (C18:2) and linolenic (C18:3) acids than oil palms. Lipids from C. humicola were believed to be acceptable for biodiesel production. DA - 2012/1// PY - 2012/1// DO - 10.1016/j.apenergy.2011.07.028 VL - 89 IS - 1 SP - 296-302 J2 - Applied Energy LA - en OP - SN - 0306-2619 UR - http://dx.doi.org/10.1016/j.apenergy.2011.07.028 DB - Crossref KW - Microalgae KW - Species screening KW - Lipid KW - Culture medium KW - Chlorococcum humicola ER - TY - JOUR TI - Design, development, and testing of an autonomous boat to reduce predatory birds on aquaculture ponds AU - Price, R.R. AU - Hall, S.G. T2 - Biological Engineering Transactions DA - 2012/// PY - 2012/// VL - 5 IS - 2 SP - 61-70 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84862545998&partnerID=MN8TOARS ER - TY - JOUR TI - Advanced Oxidation of Toluene Using Ni-Olivine Catalysts: Part 1. Synthesis, Characterization, and Evaluation of Ni-Olivine Catalysts for Toluene Oxidation AU - Smith, V. M. AU - Kolar, P. AU - Boyette, M. D. AU - Chinn, M. AU - Smith, C. AU - Gangadharan, R. AU - Zhang, G. T2 - Transactions of the ASABE AB - This research focused on advanced oxidation of toluene by evaluating Ni-olivine catalysts in combination with ozone. Specifically, our objectives were to: (1) synthesize catalysts via electroless plating (ELP) and thermal impregnation (TI) techniques to impregnate nickel onto the olivine surface; (2) characterize Ni-olivine catalysts by Brunauer-Emmett-Teller specific surface area, electron microscopy, energy dispersive spectroscopy, and x-ray photoelectron spectroscopy to understanding the mechanisms of toluene oxidation; (3) determine the catalytic activity of the newly synthesized Ni-olivine catalysts in the oxidation of toluene; and (4) evaluate the influence of varying toluene and ozone concentrations on Ni-olivine oxidation efficiencies. Testing was performed in a continuous packed bed reactor (200C). Toluene (200 to 600 ppmv) and ozone (70 to 800 ppmv) were injected into the heated reactor, while inlet and outlet concentrations were measured using gas chromatography. Results indicated that 90% of toluene was oxidized within a 1 s residence time using ELP and TI catalyst synthesis techniques and 70 ppmv ozone. Microscopic and spectroscopic analyses revealed porous structures and a nickel film uniformly coating the electroless plated olivine surface, mostly comprised of Ni-P-O, while the thermally impregnated Ni-olivine possessed sparingly deposited Ni2O3 compounds on the surface. An increase in ozone concentrations increased toluene oxidation efficiencies, whereas an increase in toluene concentrations temporarily decreased toluene oxidation efficiencies. Knowledge obtained from this research can be used for synthesizing advanced catalysts for toluene oxidation at significantly lower temperature. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41499 VL - 55 IS - 3 SP - 1013-1024 LA - en OP - SN - 2151-0040 UR - http://dx.doi.org/10.13031/2013.41499 DB - Crossref ER - TY - JOUR TI - Consolidated Bioprocessing of Lignocellulosic Feedstocks for Ethanol Fuel Production AU - Schuster, Brian G. AU - Chinn, Mari S. T2 - BioEnergy Research DA - 2012/12/4/ PY - 2012/12/4/ DO - 10.1007/s12155-012-9278-z VL - 6 IS - 2 SP - 416-435 J2 - Bioenerg. Res. LA - en OP - SN - 1939-1234 1939-1242 UR - http://dx.doi.org/10.1007/s12155-012-9278-z DB - Crossref KW - Bio-ethanol KW - Fuel KW - Consolidated bioprocessing KW - Simultaneous saccharification and fermentation KW - Co-cultures KW - Enzyme hydrolysis KW - Pretreatment ER - TY - JOUR TI - Trapping phosphorus in runoff with a phosphorus removal structure AU - Penn, C.J. AU - McGrath, J.M. AU - Rounds, E. AU - Fox, G. AU - Heeren, D. T2 - Journal of Environmental Quality AB - Reduction of phosphorus (P) inputs to surface waters may decrease eutrophication. Some researchers have proposed filtering dissolved P in runoff with P-sorptive byproducts in structures placed in hydrologically active areas with high soil P concentrations. The objectives of this study were to construct and monitor a P removal structure in a suburban watershed and test the ability of empirically developed flow-through equations to predict structure performance. Steel slag was used as the P sorption material in the P removal structure. Water samples were collected before and after the structure using automatic samples and analyzed for total dissolved P. During the first 5 mo of structure operation, 25% of all dissolved P was removed from rainfall and irrigation events. Phosphorus was removed more efficiently during low flow rate irrigation events with a high retention time than during high flow rate rainfall events with a low retention time. The six largest flow events occurred during storm flow and accounted for 75% of the P entering the structure and 54% of the P removed by the structure. Flow-through equations developed for predicting structure performance produced reasonable estimates of structure "lifetime" (16.8 mo). However, the equations overpredicted cumulative P removal. This was likely due to differences in pH, total Ca and Fe, and alkalinity between the slag used in the structure and the slag used for model development. This suggests the need for an overall model that can predict structure performance based on individual material properties. DA - 2012/// PY - 2012/// DO - 10.2134/jeq2011.0045 VL - 41 IS - 3 SP - 672-679 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84862244589&partnerID=MN8TOARS ER - TY - JOUR TI - Using rapid geomorphic assessments to assess streambank stability in oklahoma ozark streams AU - Heeren, D.M. AU - Mittelstet, A.R. AU - Fox, G.A. AU - Storm, D.E. AU - Al-Madhhachi, A.T. AU - Midgley, T.L. AU - Stringer, A.F. AU - Stunkel, K.B. AU - Tejral, R.D. T2 - Transactions of the ASABE DA - 2012/// PY - 2012/// VL - 55 IS - 3 SP - 957-968 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84863663950&partnerID=MN8TOARS ER - TY - JOUR TI - Streambank research facility at Oklahoma State university AU - Lovern, S.B. AU - Fox, G. T2 - Resource: Engineering and Technology for Sustainable World DA - 2012/// PY - 2012/// VL - 19 IS - 2 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84861991539&partnerID=MN8TOARS ER - TY - CONF TI - Streambank piping and internal erosion as failure mechanisms of streambanks AU - Midgley, T.L. AU - Fox, G.A. AU - Wilson, G.V. AU - Felice, R.M. C2 - 2012/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2012, ASABE 2012 DA - 2012/// VL - 2 SP - 931-945 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84871750753&partnerID=MN8TOARS ER - TY - JOUR TI - Sorption of Escherichia Coli in agricultural soils influenced by swine manure constituents AU - Guzman, J.A. AU - Fox, G.A. AU - Penn, C.J. T2 - Transactions of the ASABE DA - 2012/// PY - 2012/// VL - 55 IS - 1 SP - 61-71 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84859750458&partnerID=MN8TOARS ER - TY - JOUR TI - Streambank Piping and Internal Erosion as Failure Mechanisms of Streambanks AU - Midgley, Taber L AU - Fox, Garey A AU - Felice, Rachel M AU - Wilson, Glenn V T2 - 2012 Dallas, Texas, July 29 - August 1, 2012 AB - Soil piping has been attributed as a potential mechanism of instability of embankments and streambanks. Limited field work has been conducted on quantifying and modeling pipeflow and internal erosion processes in the field with either natural or artificially created soil pipes. This research utilized an innovative constant-head trench system to conduct constant head soil pipe experiments in two contrasting streambanks: Dry Creek in northern Mississippi and Cow Creek in northern Oklahoma. Experiments included open pipes where the soil pipe was directly connected to the constant-head trench and open at the streambank face and clogged pipes which involved plugging the outlet of the soil pipe using soil excavated adjacent to the pipe. A tensiometer network was used to measure soil water pressures surrounding open and clogged pipe outlets on the streambank face. When pipeflow occurred, flow and sediment samples were collected using flow collection pans to quantify sediment concentrations and pipe enlargement. Flow and sediment data were used with an existing turbulent pipeflow and internal erosion model to estimate erodibility and critical shear stress properties of the soils, which were subsequently compared to similar properties derived from jet erosion tests. Clogged soil pipes resulted in pore water pressure increases in the soil adjacent to the pipe, which generally remained below saturation during these experimental periods, except locations close to the plug. Depending on the density of the plugged soil material, the clogged soil pipes either burst resulting in turbulent pipeflow or were manually punctured to establish pipeflow. Calibrated critical shear stress from the turbulent pipeflow and internal erosion model matched that observed from jet erosion tests for the less erodible soils on the Dry Creek streambank where sediment concentrations were consistently below 2 g L-1 even with fairly large hydraulic gradients on the pipe (0.3 m m-1). Calibrated erodibility coefficients were much smaller than those measured with jet erosion tests. For the more erodible streambank soils of Cow Creek, sediment concentrations approached 40 g L-1. There is a need for improved pipeflow modeling that accounts for partially filled soil pipes and pipeflow/soil matrix interactions leading to cases of steady flow rates but increasing sediment concentrations during the initial stages of pipeflow. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41757 ER - TY - JOUR TI - Seepage and piping: Solitary and integrated mechanisms of streambank erosion and failure AU - Fox, G. AU - Wilson, G.V. T2 - Resource: Engineering and Technology for Sustainable World DA - 2012/// PY - 2012/// VL - 19 IS - 2 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84861981195&partnerID=MN8TOARS ER - TY - CONF TI - Quantification and heterogeneity of infiltration and transport in alluvial floodplains AU - Heeren, D.M. AU - Fox, G.A. AU - Storm, D.E. AU - Storm, P.Q. AU - Haggard, B.E. AU - Halihan, T. AU - Miller, R.B. C2 - 2012/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2012, ASABE 2012 DA - 2012/// VL - 1 SP - 647-667 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84871725648&partnerID=MN8TOARS ER - TY - JOUR TI - Implementation of biopore and soil fecal bacteria fate and transport routines in the root zone water quality model (RZWQM) AU - Guzman, J.A. AU - Fox, G.A. T2 - Transactions of the ASABE DA - 2012/// PY - 2012/// VL - 55 IS - 1 SP - 73-84 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84859784669&partnerID=MN8TOARS ER - TY - JOUR TI - Rational polynomial functions for modeling E. coli and bromide breakthrough AU - Meek, D.W. AU - Hoang, C.K. AU - Malone, R.W. AU - Kanwar, R.S. AU - Fox, G.A. AU - Guzman, J.A. AU - Shipitalo, M.J. T2 - Transactions of the ASABE DA - 2012/// PY - 2012/// VL - 55 IS - 5 SP - 1821-1826 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84872293127&partnerID=MN8TOARS ER - TY - CONF TI - Development a fluvial detachment rate model to predict the erodibility of cohesive soils under the influence of seepage AU - Al-Madhhachi, A.-S.T. AU - Fox, G.A. AU - Hanson, G.J. AU - Tyagi, A.K. AU - Bulut, R. C2 - 2012/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2012, ASABE 2012 DA - 2012/// VL - 2 SP - 946-975 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84871816499&partnerID=MN8TOARS ER - TY - CONF TI - Controlled laboratory experiments investigating the influence of shallow groundwater tables on runoff through vegetative filter strips AU - Purvis, R. AU - Fox, G.A. C2 - 2012/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2012, ASABE 2012 DA - 2012/// VL - 2 SP - 976-986 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84871807759&partnerID=MN8TOARS ER - TY - CONF TI - Berm method for quantification of infiltration and leaching at the plot scale in high conductivity soils AU - Heeren, D.M. AU - Fox, G.A. AU - Storm, D.E. C2 - 2012/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2012, ASABE 2012 DA - 2012/// VL - 1 SP - 668-677 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84871740999&partnerID=MN8TOARS ER - TY - JOUR TI - Quantification and Heterogeneity of Infiltration and Transport in Alluvial Floodplains AU - Heeren, Derek M AU - Fox, Garey A AU - Storm, Daniel E AU - Storm, Peter Q AU - Haggard, Brian E AU - Halihan, Todd AU - Miller, Ronald B T2 - 2012 Dallas, Texas, July 29 - August 1, 2012 AB - In order to protect drinking water systems and aquatic ecosystems, all critical nutrient source areas and transport mechanisms need to be characterized. It is hypothesized that hydrologic heterogeneities (e.g., macropores and gravel outcrops) in the subsurface of floodplains play an integral role in impacting flow and contaminant transport between the soil surface and shallow alluvial aquifers which are intricately connected to streams. Infiltration is often assumed to be uniform at the field scale, but this neglects the high spatial variability common in anisotropic, heterogeneous alluvial floodplain soils. In the Ozark ecoregion, for example, the erosion of carbonate bedrock (primarily limestone) by slightly acidic water has left a large residuum of chert gravel in Ozark soils, with floodplains generally consisting of coarse chert gravel overlain by a mantle (1 to 300 cm) of gravelly loam or silt loam. The process of alluvial sediment deposition is highly variable, and can cause gravel layers to outcrop on the soil surface at various locations within a floodplain. The objective of this research was to quantify heterogeneity in infiltration rates at three floodplain sites in the Ozark ecoregion of Oklahoma and Arkansas. Innovative field studies, including plot scale (1 by 1 m and 3 by 3 m) solute injection experiments along with geophysical imaging, were performed on both gravel outcrops and non-gravel outcrops. Plots maintained a constant head of 3 to 10 cm for up to 48 hours. Infiltration rates varied from 0.8 to 70 cm/h, and varied considerably even within a single floodplain. Electrical resistivity imaging was used to identify zones of preferential flow as well as characterize subsurface soil layering. Fluid samples from observation wells outside the plot (0.5 m from the boundary) indicated nonuniform subsurface flow and transport. Phosphorus was detected in the groundwater for 6 of the 12 plots and was positively correlated to the presence of gravel outcrops. Results indicated that flow paths are sub-meter scale for detecting infiltrating solutions. Tension infiltrometers showed that macropore flow accounted for approximately 85% to 99% of the total infiltration. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41740 ER - TY - JOUR TI - E. coli transport through surface-connected biopores identified from smoke injection tests AU - Fox, G.A. AU - Marvin, M.M. AU - Guzman, J.A. AU - Hoang, C.K. AU - Malone, R.W. AU - Kanwar, R.S. AU - Shipitalo, M.J. T2 - Transactions of the ASABE DA - 2012/// PY - 2012/// VL - 55 IS - 6 SP - 2185-2194 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84872566252&partnerID=MN8TOARS ER - TY - JOUR TI - Controlled Laboratory Experiments Investigating the Influence of Shallow Groundwater Tables on Runoff through Vegetative Filter Strips AU - Purvis, Rebecca AU - Fox, Garey A T2 - 2012 Dallas, Texas, July 29 - August 1, 2012 AB - Vegetative filter strips (VFS) are implemented adjacent to surface water bodies with the purpose of slowing down runoff and allowing for infiltration and settling of particles. However, there is currently limited data demonstrating how VFS perform under shallow water table conditions. Future versions of VFS design models are being constructed for this case and therefore a need exists to derive data to validate the model. The objectives of this research were to simulate a VFS in a controlled laboratory setting to quantify the influence of shallow groundwater tables on runoff. A steel box (100 cm wide, 200 cm long and 70 cm deep) was used to simulate surface runoff through a VFS. A silt loam soil was packed in the box and planted with Bermuda grass. Five experiments were performed by controlling the groundwater table including a free drainage case, a series of static water table cases, and a dynamic water table case. Precipitation was not considered in these experiments. Water was evenly distributed onto the upslope end of the VFS at a steady rate and outflow measured at the downslope end. The influence of the water table position on the outflow rate and infiltration was determined. As expected, results indicated that the higher the groundwater table the less infiltration occurred. A water table near the ground surface (1 to 2 cm) for this silt loam soil was required to limit infiltration such that the inflow and outflow rates were approximately equivalent. The dynamic water table case demonstrated that the water table can rapidly increase near the soil surface due to infiltration in the VFS. In cases with shallow groundwater, less infiltration will result in less removal of contaminants in the runoff and therefore greater quantities of contaminants reaching nearby surface water bodies. The experimental data will be critical for validating future VFS design models that will consider the performance of VFS in areas of shallow groundwater. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41758 ER - TY - JOUR TI - Authors' Reply AU - Fox, G.A. AU - Miller, R.B. AU - Heeren, D.M. AU - Storm, D.E. AU - Halihan, T. T2 - Ground Water AB - GroundwaterVolume 50, Issue 4 p. 513-513 Authors' Reply Garey A. Fox, Corresponding Author Garey A. Fox Corresponding author: Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK 74078; [email protected]Search for more papers by this authorRonald B. Miller, Ronald B. Miller Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK 74078.Search for more papers by this authorDerek M. Heeren, Derek M. Heeren Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK 74078.Search for more papers by this authorDaniel E. Storm, Daniel E. Storm Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK 74078.Search for more papers by this authorTodd Halihan, Todd Halihan School of Geology, Oklahoma State University, Stillwater, OK 74078.Search for more papers by this author Garey A. Fox, Corresponding Author Garey A. Fox Corresponding author: Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK 74078; [email protected]Search for more papers by this authorRonald B. Miller, Ronald B. Miller Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK 74078.Search for more papers by this authorDerek M. Heeren, Derek M. Heeren Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK 74078.Search for more papers by this authorDaniel E. Storm, Daniel E. Storm Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK 74078.Search for more papers by this authorTodd Halihan, Todd Halihan School of Geology, Oklahoma State University, Stillwater, OK 74078.Search for more papers by this author First published: 26 April 2012 https://doi.org/10.1111/j.1745-6584.2012.00939.xCitations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. References Fuchs , J.W. , G.A. Fox , D.E. Storm , C. Penn , and G.O. Brown . 2009 . Subsurface transport of phosphorus in riparian floodplains: Influence of preferential flow pathways. Journal of Environmental Quality 38 , no. 2 : 473 – 484. Miller , R.B. , D.M. Heeren , G.A. Fox , D.E. Storm , and T. Halihan . 2011 . Design and application of a direct-push vadose zone gravel permeameter. Groundwater 49 , no. 6 : 920 – 925. Reynolds , W.D. 2010 . Measuring soil hydraulic properties using a cased borehole permeameter: Steady flow analyses. Vadose Zone Journal 9 , 637 – 651. U.S. Bureau of Reclamation (USBR). 1985 . Ground Water Manual: A Water Resources Technical Manual . Revised Reprint. Denver, Colorado : U.S. Department of the Interior, Bureau of Reclamation. Citing Literature Volume50, Issue4July/August 2012Pages 513-513 ReferencesRelatedInformation DA - 2012/// PY - 2012/// DO - 10.1111/j.1745-6584.2012.00939.x VL - 50 IS - 4 SP - 513-513 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84863305337&partnerID=MN8TOARS ER - TY - JOUR TI - Evaluation of the bank stability and toe erosion model (BSTEM) for predicting lateral retreat on composite streambanks AU - Midgley, T.L. AU - Fox, G.A. AU - Heeren, D.M. T2 - Geomorphology AB - Streambank erosion is known to be a major source of sediment in streams and rivers. The Bank Stability and Toe Erosion Model (BSTEM) was developed in order to predict streambank retreat due to both fluvial erosion and geotechnical failure. However, few, if any, model evaluations using long-term streambank retreat data have been performed. The objectives of this research were to (1) monitor long-term composite streambank retreat during a hydraulically active period on a rapidly migrating stream, (2) evaluate BSTEM's ability to predict the measured streambank retreat, and (3) assess the importance of accurate geotechnical, fluvial erosion, and near-bank pore-water pressure properties. The Barren Fork Creek in northeastern Oklahoma laterally eroded 7.8 to 20.9 m along a 100-m length of stream between April and October 2009 based on regular bank location surveys. The most significant lateral retreat occurred in mid- to late-May and September due to a series of storm events, and not necessarily the most extreme events observed during the monitoring period. BSTEM (version 5.2) was not originally programmed to run multiple hydrographs iteratively, so a subroutine was written that automatically input the temporal sequence of stream stage and to lag the water table in the near-bank ground water depending on user settings. Eight BSTEM simulations of the Barren Fork Creek streambank were performed using combinations of the following input data: with and without a water table lag; default BSTEM geotechnical parameters (moderate silt loam) versus laboratory measured geotechnical parameters based on direct shear tests on saturated soil samples; and default BSTEM fluvial erosion parameters versus field measured fluvial erosion parameters from submerged jet tests. Using default BSTEM input values underestimated the actual erosion that occurred. Lagging the water table predicted more geotechnical failures resulting in greater streambank retreat. Using measured fluvial and geotechnical parameters and a water table lag also under predicted retreat (approximately 3.3 m), but did predict the appropriate timing of streambank collapses. The under prediction of retreat was hypothesized to be due to over predicting the critical shear stress of the non-cohesive gravel, under predicting the erodibility of the non-cohesive gravel, and/or under predicting the imposed shear stress acting on the streambank. Current research improving our understanding of shear stress distributions, streambank pore-water pressure dynamics, and methods for estimating excess shear stress parameters for noncohesive soils will be critical for improving BSTEM and other streambank stability models. DA - 2012/4// PY - 2012/4// DO - 10.1016/j.geomorph.2011.12.044 VL - 145-146 SP - 107-114 UR - http://dx.doi.org/10.1016/j.geomorph.2011.12.044 KW - BSTEM KW - Fluvial erosion KW - Mass wasting KW - Ozark ecoregion KW - Streambank erosion KW - Streambank stability ER - TY - JOUR TI - Berm Method for Quantification of Infiltration and Leaching at the Plot Scale in High Conductivity Soils AU - Heeren, Derek M AU - Fox, Garey A AU - Storm, Daniel E T2 - 2012 Dallas, Texas, July 29 - August 1, 2012 AB - Measuring infiltration and leaching at the plot scale is difficult, especially for high hydraulic conductivity soils. Infiltration rate has been indirectly calculated at the plot scale by comparing surface runoff to rainfall. Direct measurement of infiltration and leaching beyond the point scale is typically limited to locations where land forming has been performed, e.g. infiltration ponds and fields with basin irrigation. The standard method for field measurement of infiltration is a double ring infiltrometer, which is limited in size (typically 30 cm diameter). In this research, a new method is proposed that uses a temporary berm constructed of a water filled 15 cm diameter vinyl hose with the edges sealed to the soil using bentonite. The berm is capable of confining infiltration plot areas of various sizes (e.g. 1 m by 1 m and 3 m by 3 m areas in this research). Water tanks (0.8 m3 and 4.9 m3) and gravity flow were used to supply water and tracers to the plots. A constant head was maintained within the plot automatically using float valves for lower flow rates and manually with a gate valve for higher flow rates. Observation wells were installed 0.5 m outside the plot to monitor for water table rise and tracers that leached into the groundwater. The procedure was tested on soils ranging from silt loam to coarse gravel with measured infiltration rates ranging from 5 to 70 cm/hr. Guidelines are provided for tank size and refilling frequency for field experiments. In addition, numerical simulations were performed to estimate time of response in wells for various soil and experimental design conditions. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41741 ER - TY - JOUR TI - River flux uncertainties predicted by hydrological variability and riverine material behaviour AU - Moatar, Florentina AU - Meybeck, Michel AU - Raymond, Sébastien AU - Birgand, François AU - Curie, Florence T2 - Hydrological Processes AB - Abstract Data on riverine fluxes are essential for calculating element cycles (carbon, nutrients, pollutants) and erosion rates from regional to global scales. At most water‐quality stations throughout the world, riverine fluxes are calculated from continuous flow data ( q ) and discrete concentration data ( C ), the latter being the main cause of sometimes large uncertainties. This article offers a comprehensive approach for predicting the magnitude of these uncertainties for water‐quality stations in medium to large basins (drainage basin area > 1000 km²) based on the commonly used discharge‐weighted method. Uncertainty levels – biases and imprecisions – for sampling intervals of 3 to 60 days are correlated first through a nomograph with a flux variability indicator, the quantity of riverine material discharged in 2% of time ( M 2% ). In turn, M 2% is estimated from the combination of a hydrological reactivity index, W 2% (the cumulative flow volume discharged during the upper 2% of highest daily flow) and the truncated b 50sup exponent, quantifying the concentration versus discharge relationship for the upper half of flow values ( C = a q b 50sup , for q > q 50 , where q 50 is the median flow): M 2% = W 2% + 27.6 b 50sup . W 2% can be calculated from continuous flow measurements, and the b 50sup indicator can be calculated from infrequent sampling, which makes it possible to predict a priori the level of uncertainty at any station, for any type of riverine material either concentrated ( b 50sup > 0) or diluted ( b 50sup > 0) with flow. A large data base of daily surveys, 125 station variables of suspended particulate matter (SPM), total dissolved solids (TDS) and dissolved and particulate nutrients, was used to determine uncertainties from simulated discrete surveys and to establish relationships between indicators. Results show, for example, that for the same relatively reactive basin ( W 2% > 25%), calculated fluxes from monthly sampling would yield uncertainties approaching ±100% for SPM ( b 50sup > 1.4) fluxes and ±10% for TDS ( b 50sup = −0.2). The application to the nitrate survey of the river Seine shows significant trends for the 1972–2009 records. Copyright © 2012 John Wiley & Sons, Ltd. DA - 2012/8/2/ PY - 2012/8/2/ DO - 10.1002/hyp.9464 VL - 27 IS - 25 SP - 3535-3546 J2 - Hydrol. Process. LA - en OP - SN - 0885-6087 UR - http://dx.doi.org/10.1002/hyp.9464 DB - Crossref KW - riverine fluxes KW - flux duration indicators KW - uncertainties KW - suspended particulate matter KW - total dissolved solids KW - nutrients ER - TY - JOUR TI - Particulate matter in the vicinity of an egg production facility: Concentrations, statistical distributions, and upwind and downwind comparison AU - Li, Q.-F. AU - Wang-Li, L. AU - Walker, J.T. AU - Shah, S.B. AU - Bloomfield, P. AU - Jayanty, R.K.M. T2 - Transactions of the ASABE DA - 2012/// PY - 2012/// VL - 55 IS - 5 SP - 1965-1973 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84872306478&partnerID=MN8TOARS ER - TY - JOUR TI - Impact of downwind sampling location and height on inverse-Gaussian dispersion modeling: A theoretical study AU - Jones, H.W. AU - Wang-Li, L. AU - Boroujeni, B.Y. T2 - International Journal of Agricultural and Biological Engineering DA - 2012/// PY - 2012/// DO - 10.3965/j.ijabe.20120504.00 VL - 5 IS - 4 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84871271494&partnerID=MN8TOARS ER - TY - JOUR TI - Influence of Aeration Rate on the Physio-Chemical Characteristics of Biodried Dairy Manure - Wheat Straw Mixture AU - Sharara, M. A. AU - Sadaka, S. AU - Costello, T. A. AU - VanDevender, K. T2 - Applied Engineering in Agriculture AB - Animal manure is a prime candidate for thermochemical conversion (co-firing, gasification, and pyrolysis) except for its high moisture content. Biodrying is a promising solution to reduce manure moisture with minimum energy input. This study investigated the effects of different aeration rates; low (0.05 L/min/kg VM), medium (0.80 L/min/kgVM), and high (1.50 L/min/kgVM), on the biodrying of dairy manure mixed with wheat straw. The moisture content dropped in 21 days from 56% to 28%, 34%, and 35% wb under high, medium, and low aeration rates, respectively. The heating value of the mixture decreased from 16.19 MJ/kgdry to 14.31, 13.79, and 13.83 MJ/kgdry under high, medium, and low aeration, respectively. Evaluation of energy consumption to remove a unit mass of moisture showed that high aeration levels required the least energy input, 7.84 MJ/kgH2O, followed by low aeration at 7.93 MJ/ kgH2O, while the medium aeration had a relatively high energy cost for water removal, 9.09 MJ/ kgH2O. The high aeration level was superior in terms of both drying energy and time requirements to the other rates considered. Comparison showed that high aeration level biodrying (1.50 L/min/kgVM) exceeded the range of conventional drying energy demand. However, the ratio of external fossil fuel demand was much lower in biodrying (due to the auto-thermal effect) than in conventional drying. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41489 VL - 28 IS - 3 SP - 407-415 ER - TY - CONF TI - Auger reactor gasification of algal blooms produced in a waste water treatment facility AU - Sharara, Mahmoud A AU - Sadaka, Samy S T2 - American Society of Agricultural and Biological Engineers C2 - 2012/// C3 - 2012 Dallas, Texas, July 29-August 1, 2012 DA - 2012/// SP - 1 ER - TY - CHAP TI - An overview of biorefinery technology AU - Sharara, Mahmoud A AU - Clausen, Edgar C AU - Carrier, Danielle Julie T2 - Biorefinery Co-Products: Phytochemicals. Primary Metabolites and Value-Added Biomass Processing PY - 2012/// SP - 1-18 PB - Wiley ER - TY - JOUR TI - Virus-induced gene silencing in diverse maize lines using the Brome Mosaic virus-based silencing vector AU - Benavente, L.M. AU - Ding, X.S. AU - Redinbaugh, M.G. AU - Nelson, R.S. AU - Balint-Kurti, P. T2 - Maydica DA - 2012/// PY - 2012/// VL - 57 IS - 3-4 SP - 206-214 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84875615027&partnerID=MN8TOARS ER - TY - RPRT TI - Worms can recycle your garbage AU - Sherman, R. A3 - NC State Cooperative Extension DA - 2012/// PY - 2012/// M1 - AG‐473‐18 PB - NC State Cooperative Extension SN - AG‐473‐18 ER - TY - JOUR TI - Temporal analysis of stormwater control measure effluent based on windows of harmful algal bloom (HAB) sensitivity: Are annual nutrient EMCs appropriate during HAB-sensitive seasons? AU - Hathaway, Jon M. AU - Moore, Trisha L. C. AU - Burkholder, JoAnn M. AU - Hunt, William F. T2 - ECOLOGICAL ENGINEERING AB - Nutrient removal by stormwater control measures (SCMs) is typically reported in terms of an average annual percent removal or effluent concentration. However, when the performance of these systems is considered in light of downstream receiving aquatic ecosystems, which display seasonal sensitivities to nutrient loadings, the use of an annual-based metric seems arbitrary. To investigate the potential temporal mismatch between nutrient-sensitive periods in receiving water bodies and average annual reporting periods adopted for SCM performance metrics, a case study is presented for four SCM types (constructed stormwater wetlands, bioretention, vegetated filter strips, and swales) draining to the Neuse River Estuary (NRE) in North Carolina, USA. Outbreaks of harmful algal blooms (HABs) in the NRE have been related to different nutrient forms at different times of the year, resulting in a “window” of importance for a given nutrient. These windows were utilized herein to define seasons of interest for various pollutants, and thus how SCM effluent data should be grouped to evaluate seasonal differences in performance. Effluent SCM nutrient concentrations were analyzed on an annual and HAB-sensitive seasonal basis. Although the use of annual performance metrics was deemed either appropriate or conservative for total phosphorus and nitrate–nitrite, effluent concentrations of total ammonia–nitrogen were significantly higher during HAB-sensitive seasons from both bioretention areas and stormwater wetlands. In the case of the NRE, these data suggest SCMs such as bioretention and stormwater wetlands may perform less effectively during periods of HAB sensitivity and that the contribution of SCMs to HAB control in sensitive water bodies may be overstated using presently accepted annual evaluation metrics. Though the seasonal analysis presented is specific to HAB formation in the Neuse River Estuary, evaluation of SCM effluent nutrient concentrations on the basis of nutrient-sensitive periods in receiving water bodies has broad application to evaluation of SCMs in any nutrient-sensitive watershed. The present study suggests that evaluation of SCM performance with respect to nutrient-sensitive periods in receiving aquatic ecosystems warrants further study. DA - 2012/12// PY - 2012/12// DO - 10.1016/j.ecoleng.2012.08.014 VL - 49 SP - 41-47 SN - 1872-6992 KW - Harmful algal bloom KW - Stormwater KW - BMP KW - SCM KW - Performance KW - Metrics KW - Stormwater wetland KW - Bioretention KW - Filter strip KW - Swale ER - TY - CONF TI - Characteristics of cellulose-degrading microbes in anaerobic co-digestion of swine manure with corn stover for biogas production AU - Wei, T. Y. AU - You, Z. Y. AU - Liu, Z. M. AU - Gontupil, J. AU - Cheng, J. J. C2 - 2012/// C3 - Proceeding of the 4th International Conference on Pulping, Papermaking and Biotechnology (ICPPB '12), vols. I and II DA - 2012/// SP - 649-653 ER - TY - JOUR TI - Stormwater in urban areas AU - Rauch, Wolfgang AU - Ledin, Anna AU - Eriksson, Eva AU - Deletic, Ana AU - Hunt, William F., III T2 - WATER RESEARCH AB - Collection, storage and treatment of stormwater in urban areas has been one of the classical disciplines of sanitary and environmental engineering in the past. Waste and pollution transported by st ... DA - 2012/12/15/ PY - 2012/12/15/ DO - 10.1016/j.watres.2012.10.044 VL - 46 IS - 20 SP - 6588-6588 SN - 0043-1354 ER - TY - JOUR TI - PhenoPhyte: a flexible affordable method to quantify 2D phenotypes from imagery AU - Green, Jason M AU - Appel, Heidi AU - Rehrig, Erin MacNeal AU - Harnsomburana, Jaturon AU - Chang, Jia-Fu AU - Balint-Kurti, Peter AU - Shyu, Chi-Ren T2 - Plant Methods AB - Abstract Background Accurate characterization of complex plant phenotypes is critical to assigning biological functions to genes through forward or reverse genetics. It can also be vital in determining the effect of a treatment, genotype, or environmental condition on plant growth or susceptibility to insects or pathogens. Although techniques for characterizing complex phenotypes have been developed, most are not cost effective or are too imprecise or subjective to reliably differentiate subtler differences in complex traits like growth, color change, or disease resistance. Results We designed an inexpensive imaging protocol that facilitates automatic quantification of two-dimensional visual phenotypes using computer vision and image processing algorithms applied to standard digital images. The protocol allows for non-destructive imaging of plants in the laboratory and field and can be used in suboptimal imaging conditions due to automated color and scale normalization. We designed the web-based tool PhenoPhyte for processing images adhering to this protocol and demonstrate its ability to measure a variety of two-dimensional traits (such as growth, leaf area, and herbivory) using images from several species ( Arabidopsis thaliana and Brassica rapa ). We then provide a more complicated example for measuring disease resistance of Zea mays to Southern Leaf Blight. Conclusions PhenoPhyte is a new cost-effective web-application for semi-automated quantification of two-dimensional traits from digital imagery using an easy imaging protocol. This tool’s usefulness is demonstrated for a variety of traits in multiple species. We show that digital phenotyping can reduce human subjectivity in trait quantification, thereby increasing accuracy and improving precision, which are crucial for differentiating and quantifying subtle phenotypic variation and understanding gene function and/or treatment effects. DA - 2012/11/6/ PY - 2012/11/6/ DO - 10.1186/1746-4811-8-45 VL - 8 IS - 1 SP - 45 J2 - Plant Methods LA - en OP - SN - 1746-4811 UR - http://dx.doi.org/10.1186/1746-4811-8-45 DB - Crossref KW - Herbivory KW - Pathogens KW - Genetic variation KW - Digital phenotyping ER - TY - JOUR TI - Intra-event variability of Escherichia coli and total suspended solids in urban stormwater runoff AU - McCarthy, D. T. AU - Hathaway, J. M. AU - Hunt, W. F. AU - Deletic, A. T2 - WATER RESEARCH AB - Sediment levels are important for environmental health risk assessments of surface water bodies, while faecal pollution can introduce significant public health risks for users of these systems. Urban stormwater is one of the largest sources of contaminants to surface waters, yet the fate and transport of these contaminants (especially those microbiological) have received little attention in the literature. Stormwater runoff from five urbanized catchments were monitored for pathogen indicator bacteria and total suspended solids in two developed countries. Multiple discrete samples were collected during each storm event, allowing an analysis of intra-event characteristics such as initial concentration, peak concentration, maximum rate of change, and relative confidence interval. The data suggest that a catchment’s area influences pollutant characteristics, as larger catchments have more complex stormwater infrastructure and more variable pollutant sources. The variability of total suspended solids for many characteristics was similar to Escherichia coli, indicating that the variability of E. coli may not be substantially higher than that of other pollutants as initially speculated. Further, variations in E. coli appeared to be more commonly correlated to antecedent climate, while total suspended solids were more highly correlated to rainfall/runoff characteristics. This emphasizes the importance of climate on microbial persistence and die off in urban systems. Discrete intra-event concentrations of total suspended solids and, to a lesser extent E. coli, were correlated to flow, velocity, and rainfall intensity (adjusted by time of concentrations). Concentration changes were found to be best described by adjusted rainfall intensity, as shown by other researchers. This study has resulted in an increased understanding of the magnitude of intra-event variations of total suspended solids and E. coli and what physical and climatic parameters influence these variations. DA - 2012/12/15/ PY - 2012/12/15/ DO - 10.1016/j.watres.2012.01.006 VL - 46 IS - 20 SP - 6661-6670 SN - 0043-1354 KW - Urban runoff KW - Stormwater KW - Pollutograph KW - Microorganism KW - Escherichia coli KW - Sediment KW - TSS ER - TY - JOUR TI - Ecosystem service provision by stormwater wetlands and ponds - A means for evaluation? AU - Moore, T. L. C. AU - Hunt, W. F. T2 - Water Research AB - Stormwater control measures (SCMs) such as constructed stormwater ponds and constructed stormwater wetlands (CSWs) are designed to regulate runoff hydrology and quality. However, these created ecosystems also provide a range of other benefits, or ecosystem services, which are often acknowledged but rarely quantified. In this study, additional ecosystem services, including carbon sequestration, biodiversity, and cultural services, were assessed and compared between 20 ponds and 20 CSWs in North Carolina, USA. Carbon sequestration was estimated through the carbon content of pond and wetland sediments across a gradient of system age. Biodiversity was quantified in terms of the richness and Shannon diversity index of vegetative and aquatic macroinvertebrate communities. Cultural services were qualitatively assessed based on the potential for recreational and educational opportunities at each site. Ponds and wetlands were found to support similar levels of macroinvertebrate diversity, though differences community composition arose between the two habitat types. CSWs demonstrated greater potential to provide carbon sequestration, vegetative diversity, and cultural ecosystem services. This assessment provides an initial framework upon which future assessments of ecosystem service provision by SCMs can build. DA - 2012/// PY - 2012/// DO - 10.1016/j.watres.2011.11.026 VL - 46 IS - 20 SP - 6811-6823 ER - TY - JOUR TI - Improving conservation practices programming to protect water quality in agricultural watersheds: Lessons learned from the National Institute of Food and Agriculture-Conservation Effects Assessment Project AU - Osmond, Deanna AU - Meals, Don AU - Hoag, Dana AU - Arabi, Mazdak AU - Luloff, Al AU - Jennings, Greg AU - McFarland, Mark AU - Spooner, Jean AU - Sharpley, Andrew AU - Line, Dan T2 - JOURNAL OF SOIL AND WATER CONSERVATION AB - Nutrient enrichment and sedimentation of water resources is a significant problem in the United States and globally (Carpenter et al. 2011; Dubrovsky et al. 2010; Hilton et al. 2006). Specifically, in the United States, over 6,908 water bodies are listed as being nutrient impaired and 6,165 are sediment impaired (USEPA 2012). Agricultural nonpoint source pollution contributes, in part, to impaired water resources in many of these watersheds (NRC 2008; USEPA 2010). DA - 2012/// PY - 2012/// DO - 10.2489/jswc.67.5.122a VL - 67 IS - 5 SP - 122A-127A SN - 1941-3300 ER - TY - JOUR TI - EFFECTS OF LAWN MAINTENANCE ON NUTRIENT LOSSES VIA OVERLAND FLOW DURING NATURAL RAINFALL EVENTS AU - Spence, Porche L. AU - Osmond, Deanna L. AU - Childres, Wesley AU - Heitman, Joshua L. AU - Robarge, Wayne P. T2 - JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION AB - Spence, Porchè L., Deanna L. Osmond, Wesley Childres, Joshua L. Heitman, and Wayne P. Robarge, 2012. Effects of Lawn Maintenance on Nutrient Losses Via Overland Flow During Natural Rainfall Events. Journal of the American Water Resources Association (JAWRA) 48(5): 909‐924. DOI: 10.1111/j.1752‐1688.2012.00658.x Abstract: A sampling system was used to evaluate the effect of residential lawn management on nutrient losses via overland flow generated during natural rainfall events from three residential landscapes: a high maintenance fescue lawn (HMFL), a low maintenance fescue lawn (LMFL), and a mixed forested residential landscape (FRL). A sampling system was located in designated areas within each landscape such that 100% of the runoff follows natural flow paths to the outlet ports and collects in sterile Nalgene ® B 3 media bags (Thermo Fisher Scientific, Rochester, NY). A rainfall event was defined as producing ≥2.54 mm of water. A total of 87 rainfall events occurred during a 20‐month monitoring period. The total runoff volume collected from the LMFL was higher than from the HMFL and FRL, but on average <1% of the total rainfall was collected from the three landscapes. Mean nitrate concentrations from each lawn did not exceed 0.6 mg N/l. Nutrient unit area losses from the HMFL, LMFL, and FRL were 1,000 times less than fertilizer and throughfall inputs, which were due to the presence of well‐structured soils (low bulk densities) with high infiltration rates. This study demonstrated that the frequency of runoff, total runoff volumes, and nutrient losses during natural rainfall events are lower from highly maintained (i.e., irrigation, fertilizer application, and reseeding) densely uniform manicured lawns than low maintenance lawns and forested residential landscapes. DA - 2012/10// PY - 2012/10// DO - 10.1111/j.1752-1688.2012.00658.x VL - 48 IS - 5 SP - 909-924 SN - 1093-474X KW - lawns KW - runoff monitoring KW - developed areas KW - nutrients KW - residential KW - throughfall ER - TY - JOUR TI - Advanced oxidation of toluene using Ni-olivine catalysts: part 2. Toluene oxidation kinetics and mechanism of Ni-olivine catalysts synthesized via electroless deposition and thermal impregnation AU - Smith, V. M. AU - Kolar, P. AU - Boyette, M. D. AU - Chinn, Mari AU - Smith, C. AU - Gangadharan, R. AU - Zhang, G. T2 - Transactions of the ASABE AB - The production of synthesis gas (syngas) involves the gasification of biomass under oxygen-limited conditions, which also produces tars. Tars pose significant problems for mechanical devices by depositing on piping, resulting in clogging and engine fouling. While recent research has shown that thermally impregnated Ni-olivine has been effective in reforming tars into H2 and CO, this technique possessed limited economic feasibility due to high input energy requirements. Thus, stable, active, and inexpensive catalysts are required for effective and efficient conditioning of syngas. This research compared the activity of Ni-olivine catalysts synthesized via electroless plating (ELP) (35C) and thermal impregnation (TI) (1400C) for oxiding toluene in a flow-through reactor. The objectives were to (1) determine the kinetics of toluene oxidation, (2) propose a reaction mechanism for toluene oxidation, and (3) investigate the effect of syngas on toluene oxidation. Conversion of toluene using Ni-olivine catalysts increased with increasing ozone concentration and temperature, as well as decreasing toluene molar flow rate, and facilitated the complete oxidation of toluene. The information obtained from this research is expected to provide opportunities for efficient cleanup of tars from biomass gasification facilities at lower temperatures. DA - 2012/// PY - 2012/// DO - 10.13031/2013.42485 VL - 55 IS - 6 SP - 2273–2283 ER - TY - JOUR TI - Radiographic Evaluation of Early Periprosthetic Femoral Bone Contrast and Prosthetic Stem Alignment after Uncemented and Cemented Total Hip Replacement in Dogs AU - Mostafa, Ayman A. AU - Drueen, Svenja AU - Nolte, Ingo AU - Wefstaedt, Patrick T2 - VETERINARY SURGERY AB - Objective To radiographically evaluate periprosthetic femoral bone contrast and assess alignment of the prosthetic stem after uncemented and cemented total hip replacement ( THR ). Study Design Prospective clinical study. Animals Dogs (n = 15). Methods Dogs were classified into uncemented (n = 8) and cemented (n = 7) THR groups. Radiographs were analyzed using image processing software to evaluate femoral bone contrast (gray scale value, GV ) for each and combined modified G ruen zone(s) immediately and 4 months after THR . Modified G ruen zones were classified into 5 zones to analyze retrospectively the regional radiographic GV of the femur around uncemented and cemented prosthetic stem. Alignment of prosthetic stem was assessed immediately and 4 months postoperatively. Variables were compared by use of 2‐tailed t‐test, with P < .05 considered significant. Results Zone 1 showed significant decrease in the mean bone GV 4 months after uncemented THR . No differences in zones 1–5 after 4 months of cemented THR . Combined zones showed significant decrease in overall mean bone GV 4 months after uncemented THR . No changes were observed 4 months after cemented THR . Number of limbs with varus‐aligned femoral stem markedly increased after 4 months of uncemented THR . Conclusions Regional bone contrast and prosthetic stem alignment vary with the design of THR . DA - 2012/1// PY - 2012/1// DO - 10.1111/j.1532-950x.2011.00931.x VL - 41 IS - 1 SP - 69-77 SN - 1532-950X ER - TY - JOUR TI - Predicting the dynamic and kinematic viscosities of biodiesel-diesel blends using mid- and near-infrared spectroscopy AU - Zhang, Weibo AU - Yuan, Wenqiao AU - Zhang, Xuemin AU - Coronado, Marcelo T2 - APPLIED ENERGY AB - This work reports the use of mid- and near-infrared spectroscopy (MIR and NIR) to predict the kinematic and dynamic viscosities of biodiesel–diesel blends. A partial least square regression (PLSR) modeling method was employed to develop the calibration models based on information from four commonly used biodiesel and three different commercial diesel fuels. For MIR spectroscopy, wavelengths in the fingerprint region of 550–1500 cm−1 were chosen for developing the model. The root mean square error of prediction (RMSEP) for kinematic viscosity and dynamic viscosity were 0.114 and 0.119 mm2/s, respectively, based on the validation set that consisted of 26 biodiesel–diesel blend samples made of six different biodiesel and three different diesel fuels. For the NIR spectroscopy, the PLSR model established using the spectral regions of 1100–1500 nm, 1600–1700 nm, and 1800–2200 nm obtained better results. The RMSEP were 0.070 mm2/s for kinematic viscosity and 0.062 mm2/s for dynamic viscosity prediction. The results indicated that both MIR and NIR can be used to accurately predict the viscosities of biodiesel–diesel blends, but better results can be obtained using NIR spectroscopy. DA - 2012/10// PY - 2012/10// DO - 10.1016/j.apenergy.2012.03.013 VL - 98 SP - 122-127 SN - 0306-2619 KW - Biodiesel KW - Biodiesel density KW - Dynamic viscosity KW - Kinematic viscosity KW - Infrared spectroscopy ER - TY - JOUR TI - Interactions between fungal growth, substrate utilization and enzyme production during shallow stationary cultivation of Phanerochaete chrysosporium on cotton stalks AU - Shi, Jian AU - Sharma-Shivappa, Ratna R. AU - Chinn, Mari S. T2 - ENZYME AND MICROBIAL TECHNOLOGY AB - Microbial pretreatment of lignocellulosic feedstocks is an environment friendly alternative to physio-chemical pretreatment methods. A better understanding of the interactive fungal mechanisms in biological systems is essential for enhancing performance and facilitating scale-up and commercialization of this pretreatment technique. In this study, mathematical models were developed for describing cellulose and hemicellulose consumption, lignin degradation, cellulase and ligninolytic enzyme production and oxygen uptake associated with the growth of Phanerochaete chrysosporium during a 14-day shallow stationary submerged fungal pretreatment process on cotton stalks. Model parameters were estimated and validated by Statistics Toolbox in MatLab 7.1. Models yielded sufficiently accurate predictions for cellulose and hemicellulose consumption (R²=0.9772 and 0.9837), lignin degradation (R²=0.9879 and 0.8682) and ligninolytic enzyme production (R²=0. 8135 and 0.9693) under both 1-day and 3-day oxygen flushing conditions, respectively. The predictabilities for fungal growth (R²=0.6397 and 0.5750) and cellulase production (R²=0.0307 and 0.3046) for 1-day and 3-day oxygen flushing, respectively, and oxygen uptake (R²=0.5435) for 3-day oxygen flushing were limited. DA - 2012/6/10/ PY - 2012/6/10/ DO - 10.1016/j.enzmictec.2012.03.006 VL - 51 IS - 1 SP - 1-8 SN - 1879-0909 KW - Bioethanol KW - Phanerochaete chrysosporium KW - Kinetics KW - Pretreatment ER - TY - JOUR TI - Impact of Infrared Finishing on the Mechanical and Sensorial Properties of Wheat Donuts AU - Melito, Helen S. AU - Farkas, Brian E. T2 - JOURNAL OF FOOD SCIENCE AB - Abstract: Infrared radiation may be used to simulate an immersion frying heat flux and create products with fried‐like textures but lower fat contents. The objective of this study was to determine the process parameters needed to produce partially‐fried, infrared‐finished donuts comparable to fully‐fried (control) donuts. A total of 8 different sets of infrared oven parameters (emitter height and belt speed) were tested. Instrumental analysis showed that all infrared‐finished donuts had significantly ( P ≤ 0.05) lower fat content (25.6% to 30.6%) than the control (33.7%). Setting the infrared emitters in a height gradient from 70 to 50 mm or at a constant height of 60 mm above the belt produced donuts that were most instrumentally similar to the control. Infrared‐finished donuts had comparable ( P ≤ 0.05) overall acceptance scores to the control, 5.28 to 5.85 versus 5.83, respectively. Infrared radiation may be used to finish‐fry partially‐fried donuts, yielding a product similar to a fully‐fried donut but with significantly lower fat content. Practical Applications: The partial‐frying, infrared‐finishing process detailed in this article may be used for other deep‐fried foods. It is likely that these foods will also have a lower fat content when prepared with this process than when they are deep‐fried. This process provides a method of lowering the fat content of fried foods without changing the food formulation. DA - 2012/9// PY - 2012/9// DO - 10.1111/j.1750-3841.2012.02847.x VL - 77 IS - 9 SP - E224-E230 SN - 1750-3841 KW - donut KW - fat content KW - frying KW - infrared KW - process ER - TY - JOUR TI - Hydrocarbon Fuels From Gas Phase Decarboxylation of Hydrolyzed Free Fatty Acid AU - Wang, Wei-Cheng AU - Roberts, William L. AU - Stikeleather, Larry F. T2 - JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME AB - Gas phase decarboxylation of hydrolyzed free fatty acid (FFA) from canola oil has been investigated in two fix-bed reactors by changing reaction parameters such as temperatures, FFA feed rates, and H2-to-FFA molar ratios. FFA, which contains mostly C18 as well as a few C16, C20, C22, and C24 FFA, was fed into the boiling zone, evaporated, carried by hydrogen flow at the rate of 0.5–20 ml/min, and reacted with the 5% Pd/C catalyst in the reactor. Reactions were conducted atmospherically at 380–450 °C and the products, qualified and quantified through gas chromatography-flame ionization detector (GC-FID), showed mostly n-heptadecane and a few portion of n-C15, n-C19, n-C21, n-C23 as well as some cracking species. Results showed that FFA conversion increased with increasing reaction temperatures but decreased with increasing FFA feed rates and H2-to-FFA molar ratios. The reaction rates were found to decrease with higher temperature and increase with higher H2 flow rates. Highly selective heptadecane was achieved by applying higher temperatures and higher H2-to-FFA molar ratios. From the results, as catalyst loading and FFA feed rate were fixed, an optimal reaction temperature of 415 °C as well as H2-to-FFA molar ratio of 4.16 were presented. These results provided good basis for studying the kinetics of decarboxylation process. DA - 2012/9// PY - 2012/9// DO - 10.1115/1.4006867 VL - 134 IS - 3 SP - SN - 0195-0738 KW - Gas phase decarboxylation KW - free fatty acid KW - Pd/C KW - biofuel ER - TY - JOUR TI - Feasibility of extracting ammonia from broiler litter and scale-up considerations AU - Kolar, P. AU - Shah, S. B. AU - Love, C. D. T2 - Applied Engineering in Agriculture DA - 2012/// PY - 2012/// VL - 28 IS - 4 SP - 577-582 ER - TY - JOUR TI - Drainmod: model use, calibration, and validation AU - Skaggs, R. W. AU - Youssef, M. A. AU - Chescheir, G. M. T2 - Transactions of the ASABE AB - DRAINMOD is a process-based, distributed, field-scale model developed to describe the hydrology of poorly drained and artificially drained soils. The model is based on water balances in the soil profile, on the field surface, and, in some cases, in the drainage system. This article briefly describes the model and the algorithms that are used to quantify the various hydrologic components. Inputs for soil properties, site parameters, weather data, and crop characteristics required in the application of the model are presented and discussed with respect to their role in calibration. Methods for determining field effective values of key inputs to the model, either independently or as a part of the calibration process, are demonstrated in a case study. The case study involved calibrating DRAINMOD with two years of field data for a subsurface drained agricultural field in eastern North Carolina, followed by testing or validation of the model with two additional years of data. Performance statistics indicated that the model with calibrated input data accurately predicted daily water table depths with Nash-Sutcliffe modeling efficiency (EF) values of 0.68 and 0.72, daily drainage rates (EF = 0.73 and 0.49), and monthly drainage volumes (EF = 0.87 and 0.77) for the two-year validation period. DA - 2012/// PY - 2012/// DO - 10.13031/2013.42259 VL - 55 IS - 4 SP - 1509-1522 ER - TY - JOUR TI - CFD simulation of transient stage of continuous countercurrent hydrolysis of canola oil AU - Wang, Wei-Cheng AU - Natelson, Robert H. AU - Stikeleather, Larry F. AU - Roberts, William L. T2 - COMPUTERS & CHEMICAL ENGINEERING AB - Computational Fluid Dynamic (CFD) modeling of a continuous countercurrent hydrolysis process was performed using ANSYS-CFX. The liquid properties and flow behavior such as density, specific heats, dynamic viscosity, thermal conductivity, and thermal expansivity as well as water solubility of the hydrolysis components triglyceride, diglyceride, monoglyceride, free fatty acid, and glycerol were calculated. Chemical kinetics for the hydrolysis reactions were simulated in this model by applying Arrhenius parameters. The simulation was based on actual experimental reaction conditions including temperature and water-to-oil ratio. The results not only have good agreement with experimental data but also show instantaneous distributions of concentrations of every component in hydrolysis reaction. This model provided visible insight into the continuous countercurrent hydrolysis process. DA - 2012/8/10/ PY - 2012/8/10/ DO - 10.1016/j.compchemeng.2012.04.008 VL - 43 SP - 108-119 SN - 1873-4375 KW - CFD KW - Continuous hydrolysis KW - Triglycerides KW - Free fatty acid KW - Biofuel production ER - TY - JOUR TI - Arbuscular Mycorrhizal Fungi Increase Organic Carbon Decomposition Under Elevated CO2 AU - Cheng, Lei AU - Booker, Fitzgerald L. AU - Tu, Cong AU - Burkey, Kent O. AU - Zhou, Lishi AU - Shew, H. David AU - Rufty, Thomas W. AU - Hu, Shuijin T2 - SCIENCE AB - A Fungal Culprit to Carbon Loss In some ecosystems, such as in the layer of soil containing plant roots, fungi, and bacteria, increased levels of CO 2 should stimulate more efficient aboveground photosynthesis, which in turn should promote increased sequestration of organic carbon in soil through the protective action of arbuscular mycorrhizal fungi. However, in a series of field and microcosm experiments performed under elevated levels of CO 2 thought to be consistent with future emissions scenarios, Cheng et al. (p. 1084 ; see the Perspective by Kowalchuk ) observed that these fungi actually promote degradation of soil organic carbon, releasing more CO 2 in the process. DA - 2012/8/31/ PY - 2012/8/31/ DO - 10.1126/science.1224304 VL - 337 IS - 6098 SP - 1084-1087 SN - 1095-9203 ER - TY - JOUR TI - The binding affinity of amino acid-protein: hydroxyproline binding site I on human serum albumin AU - Zhou, X. M. AU - Lu, W. J. AU - Su, L. AU - Dong, Y. L. AU - Li, Q. F. AU - Chen, X. G. T2 - Organic & Biomolecular Chemistry DA - 2012/// PY - 2012/// VL - 10 IS - 41 SP - 8314-8321 ER - TY - JOUR TI - Temporal Variations and Controlling Factors of Nitrogen Export from an Artificially Drained Coastal Forest AU - Tian, Shiying AU - Youssef, Mohamed A. AU - Skaggs, R. Wayne AU - Amatya, Devendra M. AU - Chescheir, George M. T2 - ENVIRONMENTAL SCIENCE & TECHNOLOGY AB - Nitrogen losses in drainage water from coastal forest plantations can constrain the long term sustainability of the system and could negatively affect adjacent nutrient sensitive coastal waters. Based on long-term (21 years) field measurements of hydrology and water quality, we investigated the temporal variations and controlling factors of nitrate and dissolved organic nitrogen (DON) export from an artificially drained coastal forest over various time scales (interannual, seasonal, and storm events). According to results of stepwise multiple linear regression analyses, the observed large interannual variations of nitrate flux and concentration from the drained forest were significantly (p < 0.004) controlled by annual mean water table depth, and annual drainage or precipitation. Annual precipitation and drainage were found to be dominant factors controlling variations of annual DON fluxes. Temporal trends of annual mean DON concentration could not be explained explicitly by climate or hydrologic factors. No significant difference was observed between nitrogen (both nitrate and DON) export during growing and nongrowing seasons. Nitrate exhibited distinguished export patterns during six selected storm events. Peak nitrate concentrations during storm events were significantly (p < 0.003) related to 30-day antecedent precipitation index and the minimum water table depth during individual events. The temporal variations of DON export within storm events did not follow a clear trend and its peak concentration during the storm events was found to be significantly (p < 0.006) controlled by the short-term drying and rewetting cycles. DA - 2012/9/18/ PY - 2012/9/18/ DO - 10.1021/es3011783 VL - 46 IS - 18 SP - 9956-9963 SN - 1520-5851 ER - TY - JOUR TI - Morphology Characteristics of Southern Appalachian Wilderness Streams AU - Zink, Jason M. AU - Jennings, Gregory D. AU - Price, G. Alexander T2 - JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION AB - Zink, Jason M., Gregory D. Jennings, and G. Alexander Price, 2012. Morphology Characteristics of Southern Appalachian Wilderness Streams. Journal of the American Water Resources Association (JAWRA) 48(4): 762-773. DOI: 10.1111/j.1752-1688.2012.00647.x Abstract: Watersheds without urbanization or impacts from logging are rare in the southern Appalachian Mountains. The Joyce Kilmer/Slickrock Wilderness of North Carolina and Tennessee contains 24 km2 of old-growth forest, with the balance of the wilderness in a mature second-growth forest. The watersheds of Little Santeetlah and Slickrock Creek are located within the wilderness. Morphological information, including channel dimensions and longitudinal profiles, was gathered from 14 alluvial stream reaches in these watersheds. The study sites had drainage areas from 0.25 to 41.6 km2 and stream slopes from 0.014 to 0.104 m/m. Bankfull cross-section dimensions of the study stream reaches were strongly correlated to drainage area across the observed range of slopes and bed morphology. Cross-section area and width relationships for the streams in this study did not differ significantly from regional curves for the mountain physiographic region of North Carolina. Observations of these reaches did not suggest a definitive rule regarding the proportion of steps and riffles in streams. Pools occupied greater than 50% of the length in all stream reaches with slopes less than 0.07 m/m. Significant correlation existed between step height ratio and slope, suggesting that step height can be approximated as the product of channel width and slope. Riffle length and riffle slope ratios were also significantly correlated with slope, though pool spacing was not. DA - 2012/8// PY - 2012/8// DO - 10.1111/j.1752-1688.2012.00647.x VL - 48 IS - 4 SP - 762-773 SN - 1093-474X KW - forests KW - rivers KW - streams KW - watersheds KW - fluvial processes KW - fluvial geomorphology KW - regional curve KW - hydraulic geometry ER - TY - JOUR TI - Increasing Stream Geomorphic Stability Using Storm Water Control Measures in a Densely Urbanized Watershed AU - Tillinghast, E. D. AU - Hunt, W. F. AU - Jennings, G. D. AU - D'Arconte, Patricia T2 - JOURNAL OF HYDROLOGIC ENGINEERING AB - This study used previously established unit critical discharges, annual allowable erosional hours, and annual allowable volume of eroded bed-load standards to evaluate two types of storm water control measures (SCMs): low-impact development (LID) practices and a large detention SCM (wet pond). Nine initial scenarios modeled in PCSWMM incorporated different combinations of wet ponds, green roofs, rainwater harvesting systems, permeable pavement, and rain gardens to determine the best scenario for reducing stream erosion potential within a highly urbanized watershed in Chapel Hill, NC. The best-case scenario to reduce annual erosional hours and eroded bed load within the stream consisted of an aggressive utilization of LID practices in combination with an undersized wet pond. Although this scenario did not meet the annual erosional hour standard for rural reference streams, 0.35 h/ha/year, it did reduce erosional hours and eroded bed-load sediment by factors of 2.4 and 2.5, respectively, improving the existing condition. An alternative wet pond outlet structure that used two elevations of small drawdown orifices was explored to determine if current wet pond design practices could be improved to include stream stability. The new configuration provided a modest reduction in the number of erosional hours, a factor of 1.3, but increased the volume of eroded bed load by a factor of 1.2 when compared with the normal wet pond. However, adding widespread LID practices to the alternative outlet design reduced erosional hours and bed load transport by factors of 1.8 and 1.2, respectively, when compared with the normally configured wet pond. The failure to meet the erosional standards in all scenarios demonstrated the difficulty of requiring highly urbanized watersheds (60% impervious) to meet such strict stream protection measures. DA - 2012/12// PY - 2012/12// DO - 10.1061/(asce)he.1943-5584.0000577 VL - 17 IS - 12 SP - 1381-1388 SN - 1943-5584 KW - Low-Impact development practices KW - SWMM KW - Stream stability KW - Erosional hours KW - Sediment transport KW - Wet detention ponds ER - TY - JOUR TI - Using Variability within Digital Images to Improve Tall Fescue Color Characterization AU - Ghali, Ihab E. AU - Miller, Grady L. AU - Grabow, Garry L. AU - Huffman, Rodney L. T2 - CROP SCIENCE AB - ABSTRACT Digital image analysis (DIA) provides an accurate, nondestructive, and objective assessment of turf color. Previous research developed an index known as the dark green color index (DGCI) via DIA as an indicator of turf color. The objective of this study was to use DGCI variability to better predict a visual rating (VR) index used to evaluate tall fescue ( Festuca arundinacea Schreb.) color under different irrigation treatments. To develop DGCI statistics, two freeware software packages (Image J and R) were used to extract and process information from digital images. The model to predict VR from DIA was developed and calibrated using candidate DGCI statistical moments from 120 images in a calibration data set using a multiple linear regression procedure. Fitness of calibration and validation models were verified using the adjusted coefficient of determination, root mean square error, and the Mallow's C p statistic. The two‐variable model produced more precise estimates (adjusted R 2 = 0.926 and 0.899) than the model that only used one term in predicting the VR values (adjusted R 2 = 0.879 and 0.843) for calibration and validation sets, respectively. These data suggest incorporating a measure of color uniformity improves the use of DGCI in predicting VR values compared to using only the mean of DGCI values to predict VR values. Model refinements may be needed for other turf species, but current work suggests using additional statistical moments such as SD improves VR estimate precision and accuracy. DA - 2012/9// PY - 2012/9// DO - 10.2135/cropsci2011.10.0553 VL - 52 IS - 5 SP - 2365-2374 SN - 1435-0653 ER - TY - JOUR TI - Thermal Mitigation of Urban Storm Water by Level Spreader-Vegetative Filter Strips (vol 137, pg 707, 2011) AU - Winston, R. J. AU - Hunt, W. F. AU - Lord, W. G. T2 - JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE AB - During composition, an error was introduced on p. 711 of the original paper. The text incorrectly indicates that an afternoon storm “occurred between 12 p.m. and 7 a.m.” This should have read “7 p.m.” The complete sentence is as follows: “Overnight storms were defined as those with rainfall occurring between 9 p.m. and 6 a.m., and afternoon storms occurred between 12 p.m. and 7 p.m.” ASCE regrets this error. DA - 2012/11// PY - 2012/11// DO - 10.1061/(asce)ee.1943-7870.0000587 VL - 138 IS - 11 SP - 1165-1165 SN - 0733-9372 ER - TY - JOUR TI - Multivariate Mixed Linear Model Analysis of Longitudinal Data: An Information-Rich Statistical Technique for Analyzing Plant Disease Resistance AU - Veturi, Yogasudha AU - Kump, Kristen AU - Walsh, Ellie AU - Ott, Oliver AU - Poland, Jesse AU - Kolkman, Judith M. AU - Balint-Kurti, Peter J. AU - Holland, James B. AU - Wisser, Randall J. T2 - PHYTOPATHOLOGY AB - ABSTRACT The mixed linear model (MLM) is an advanced statistical technique applicable to many fields of science. The multivariate MLM can be used to model longitudinal data, such as repeated ratings of disease resistance taken across time. In this study, using an example data set from a multi-environment trial of northern leaf blight disease on 290 maize lines with diverse levels of resistance, multivariate MLM analysis was performed and its utility was examined. In the population and environments tested, genotypic effects were highly correlated across disease ratings and followed an autoregressive pattern of correlation decay. Because longitudinal data are often converted to the univariate measure of area under the disease progress curve (AUDPC), comparisons between univariate MLM analysis of AUDPC and multivariate MLM analysis of longitudinal data were made. Univariate analysis had the advantage of simplicity and reduced computational demand, whereas multivariate analysis enabled a comprehensive perspective on disease development, providing the opportunity for unique insights into disease resistance. To aid in the application of multivariate MLM analysis of longitudinal data on disease resistance, annotated program syntax for model fitting is provided for the software ASReml. DA - 2012/11// PY - 2012/11// DO - 10.1094/phyto-10-11-0268 VL - 102 IS - 11 SP - 1016-1025 SN - 1943-7684 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84871758907&partnerID=MN8TOARS ER - TY - JOUR TI - Drainage water management AU - Skaggs, R. Wayne AU - Fausey, Norman R. AU - Evans, Robert O. T2 - JOURNAL OF SOIL AND WATER CONSERVATION AB - This article introduces a series of papers that report results of field studies to determine the effectiveness of drainage water management (DWM) on conserving drainage water and reducing losses of nitrogen (N) to surface waters. The series is focused on the performance of the DWM (also called controlled drainage [CD]) practice in the US Midwest, where N leached from millions of acres of cropland contributes to surface water quality problems on both local and national scales. Results of these new studies are consistent with those from previous research reported in the literature that DWM can be used to reduce N losses (primarily in the nitrate nitrogen [NO3-N] form) from subsurface drained fields. The measured impact varied over a wide range (18% to more than 75% reduction in N loss to surface waters), depending on drainage system design, location, soil, and site conditions. Crop yields were increased by DWM on some sites and not on others, with the year-to-year impacts of DWM on yields dependent on weather conditions, as well as the above factors. Papers reporting advances in the development of datasets and models to predict the impact of drainage intensity and DWM on hydrology and water quality at watershed and… DA - 2012/// PY - 2012/// DO - 10.2489/jswc.67.6.167a VL - 67 IS - 6 SP - 167A-172A SN - 1941-3300 ER - TY - JOUR TI - A versatile method for preparation of hydrated microbial–latex biocatalytic coatings for gas absorption and gas evolution AU - Gosse, Jimmy L. AU - Chinn, Mari S. AU - Grunden, Amy M. AU - Bernal, Oscar I. AU - Jenkins, Jessica S. AU - Yeager, Chris AU - Kosourov, Sergey AU - Seibert, Michael AU - Flickinger, Michael C. T2 - Journal of Industrial Microbiology & Biotechnology AB - Abstract We describe a latex wet coalescence method for gas-phase immobilization of microorganisms on paper which does not require drying for adhesion. This method reduces drying stresses to the microbes. It is applicable for microorganisms that do not tolerate desiccation stress during latex drying even in the presence of carbohydrates. Small surface area, 10–65 μm thick coatings were generated on chromatography paper strips and placed in the head-space of vertical sealed tubes containing liquid to hydrate the paper. These gas-phase microbial coatings hydrated by liquid in the paper pore space demonstrated absorption or evolution of H2, CO, CO2 or O2. The microbial products produced, ethanol and acetate, diffuse into the hydrated paper pores and accumulate in the liquid at the bottom of the tube. The paper provides hydration to the back side of the coating and also separates the biocatalyst from the products. Coating reactivity was demonstrated for Chlamydomonas reinhardtii CC124, which consumed CO2 and produced 10.2 ± 0.2 mmol O2 m−2 h−1, Rhodopseudomonas palustris CGA009, which consumed acetate and produced 0.47 ± 0.04 mmol H2 m−2 h−1, Clostridium ljungdahlii OTA1, which consumed 6 mmol CO m−2 h−1, and Synechococcus sp. PCC7002, which consumed CO2 and produced 5.00 ± 0.25 mmol O2 m−2 h−1. Coating thickness and microstructure were related to microbe size as determined by digital micrometry, profilometry, and confocal microscopy. The immobilization of different microorganisms in thin adhesive films in the gas phase demonstrates the utility of this method for evaluating genetically optimized microorganisms for gas absorption and gas evolution. DA - 2012/5/17/ PY - 2012/5/17/ DO - 10.1007/s10295-012-1135-8 VL - 39 IS - 9 SP - 1269-1278 J2 - J Ind Microbiol Biotechnol LA - en OP - SN - 1367-5435 1476-5535 UR - http://dx.doi.org/10.1007/S10295-012-1135-8 DB - Crossref KW - Latex coating immobilization on chromatography paper KW - Chlamydomonas KW - Rhodopseudomonas KW - Clostridium KW - Synechococcus ER - TY - JOUR TI - A Traditional Analysis of the First Flush Effect for Nutrients in Stormwater Runoff from Two Small Urban Catchments AU - Hathaway, J. M. AU - Tucker, R. S. AU - Spooner, J. M. AU - Hunt, W. F. T2 - WATER AIR AND SOIL POLLUTION DA - 2012/11// PY - 2012/11// DO - 10.1007/s11270-012-1327-x VL - 223 IS - 9 SP - 5903-5915 SN - 1573-2932 KW - Stormwater KW - Runoff KW - First flush KW - Watershed KW - Catchment KW - TSS KW - Nutrients KW - Nitrogen KW - Phosphorus ER - TY - JOUR TI - Relationships Between Nitrogen Transformation Rates and Gene Abundance in a Riparian Buffer Soil AU - Wu, Lin AU - Osmond, Deanna L. AU - Graves, Alexandria K. AU - Burchell, Michael R. AU - Duckworth, Owen W. T2 - Environmental Management DA - 2012/8/22/ PY - 2012/8/22/ DO - 10.1007/s00267-012-9929-z VL - 50 IS - 5 SP - 861-874 J2 - Environmental Management LA - en OP - SN - 0364-152X 1432-1009 UR - http://dx.doi.org/10.1007/s00267-012-9929-z DB - Crossref KW - Riparian buffer KW - Nitrogen KW - Denitrification KW - Quantitative PCR KW - Nitrous oxide KW - Nitrate ER - TY - JOUR TI - Large-scale hydrologic modeling of the Michigan and Wisconsin agricultural regions to study impacts of land use changes AU - Nejadhashemi, A. P. AU - Wardynski, B. J. AU - Munoz, J. D. T2 - Transactions of the ASABE DA - 2012/// PY - 2012/// VL - 55 IS - 3 SP - 821-838 ER - TY - JOUR TI - Groundwater nitrate reductions within upstream and downstream sections of a riparian buffer AU - Messer, Tiffany L. AU - Burchell, Michael R., II AU - Grabow, Garry L. AU - Osmond, Deanna L. T2 - ECOLOGICAL ENGINEERING AB - The objective of this study was to evaluate the water quality benefits provided by a buffer enrolled in the North Carolina Conservation Reserve Enhancement Program (NC CREP). A 5-year study was conducted on two distinct buffer sections along the same stream to evaluate the hydrology and attenuation of groundwater nitrate (NO3−-N) entering from nearby agricultural fields. The average buffer widths were 60 m (Section 1, upstream) and 45 m (Section 2, downstream). Three transects of groundwater monitoring well nests within each buffer zone were installed to monitor water quality and water table depths for 5 years. Mean groundwater NO3−-N concentrations at the 1.5 m depth decreased from 4.5 mg L−1 to 1.7 mg L−1 and from 12.9 mg L−1 to 1.4 mg L−1 in buffer Sections 1 and 2 respectively. These differences were significant in both buffer sections (α = 0.05), but the wider Section 1 received significantly less NO3−-N than did Section 2 (P < 0.0001). Groundwater NO3−-N loads were reduced by 0.003 kg m−2 yr−1 (76% reduction) at the 1.5 m depth, while in Section 2 these loads were reduced by 0.02 kg m−2 yr−1 (94% reduction) and 0.04 kg m−2 yr−1 (86% reduction) at the 1.5 m and 3 m depths, respectively. Topography, water table and redox measurements, nitrate to chloride ratios, and deep groundwater cation analyses, indicated both sections were suitable for denitrification to proceed. However, the position of the wider Section 1 buffer in the landscape limited the amount of NO3−-N contaminated groundwater that entered from the agricultural fields, and thus could have been designed to be narrower. The effectiveness of NO3−-N reduction in riparian buffer systems is dependent on multiple landscape and biogeochemical factors and not buffer width alone. Findings provide design guidance for conservation buffer program managers as related to the influence of buffer landscape position on groundwater nitrate reduction. DA - 2012/10// PY - 2012/10// DO - 10.1016/j.ecoleng.2012.06.017 VL - 47 SP - 297-307 SN - 1872-6992 KW - Riparian buffer KW - Groundwater KW - Hydrology KW - Nitrate KW - NO3--N ER - TY - JOUR TI - Effect of Urban Catchment Composition on Runoff Temperature AU - Jones, Matthew P. AU - Hunt, William F. AU - Winston, Ryan J. T2 - JOURNAL OF ENVIRONMENTAL ENGINEERING AB - Urban runoff adversely impacts cold-water stream environments due to sporadic fluxes of thermally enriched runoff. This adversely impacts tourism in regions that support trout and salmon streams. Research on storm water control measures (SCMs) has shown that meeting the 21°C trout threshold is not consistently feasible with current SCM technologies. Thus, it is important to consider other factors in storm water temperature management, such as catchment characteristics. Median and maximum runoff temperatures from a shaded parking lot were consistently lower than those from a nearby unshaded lot. This suggests the need to implement a tree canopy cover in trout-sensitive catchments. A light-colored chip seal pavement was compared to a traditional hot-mix asphalt pavement; the light-colored chip seal produced median storm water temperatures that were 1.4°C lower than the standard hot-mix asphalt. It was shown that runoff temperature measurement location is critical when evaluating SCM performance, and that underground conveyances can substantially reduce runoff temperature. DA - 2012/12// PY - 2012/12// DO - 10.1061/(asce)ee.1943-7870.0000577 VL - 138 IS - 12 SP - 1231-1236 SN - 1943-7870 KW - Storm water KW - Trout KW - Salmon KW - Watershed KW - Thermal load ER - TY - JOUR TI - Dispersal of Deep-Sea Larvae from the Intra-American Seas: Simulations of Trajectories using Ocean Models AU - Young, Craig M. AU - He, Ruoying AU - Emlet, Richard B. AU - Li, Yizhen AU - Qian, Hui AU - Arellano, Shawn M. AU - Van Gaest, Ahna AU - Bennett, Kathleen C. AU - Wolf, Maya AU - Smart, Tracey I. AU - Rice, Mary E. T2 - INTEGRATIVE AND COMPARATIVE BIOLOGY AB - Using data on ocean circulation with a Lagrangian larval transport model, we modeled the potential dispersal distances for seven species of bathyal invertebrates whose durations of larval life have been estimated from laboratory rearing, MOCNESS plankton sampling, spawning times, and recruitment. Species associated with methane seeps in the Gulf of Mexico and/or Barbados included the bivalve “Bathymodiolus” childressi, the gastropod Bathynerita naticoidea, the siboglinid polychaete tube worm Lamellibrachia luymesi, and the asteroid Sclerasterias tanneri. Non-seep species included the echinoids Cidaris blakei and Stylocidaris lineata from sedimented slopes in the Bahamas and the wood-dwelling sipunculan Phascolosoma turnerae, found in Barbados, the Bahamas, and the Gulf of Mexico. Durations of the planktonic larval stages ranged from 3 weeks in lecithotrophic tubeworms to more than 2 years in planktotrophic starfish. Planktotrophic sipunculan larvae from the northern Gulf of Mexico were capable of reaching the mid-Atlantic off Newfoundland, a distance of more than 3000 km, during a 7- to 14-month drifting period, but the proportion retained in the Gulf of Mexico varied significantly among years. Larvae drifting in the upper water column often had longer median dispersal distances than larvae drifting for the same amount of time below the permanent thermocline, although the shapes of the distance–frequency curves varied with depth only in the species with the longest larval trajectories. Even species drifting for >2 years did not cross the ocean in the North Atlantic Drift. DA - 2012/10// PY - 2012/10// DO - 10.1093/icb/ics090 VL - 52 IS - 4 SP - 483-496 SN - 1557-7023 ER - TY - JOUR TI - Are Bioretention Cells Being Installed Per Design Standards in North Carolina? A Field Study AU - Wardynski, Brad J. AU - Hunt, William F., III T2 - JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE AB - Forty-three bioretention cells (BRCs) throughout North Carolina were assessed for maintenance needs, soil media composition, and as-built surface storage volume to determine whether BRCs are typically constructed per their intended design specifications. Visual inspections identified hydric soils and redoximorphic features (indicators of prolonged anaerobic conditions) and quantified the occurrence of issues requiring maintenance. Particle-size distribution and permeability of soil media were measured at multiple locations within each cell, and topographic surveys were performed to calculate as-built surface storage volumes. Field drawdown tests were used to verify permeability measurements and assess overall BRC function. Of the studied cells, 22% contained redoximorphic features in the upper 30 cm, and 53% were in need of maintenance due to one or more factors. Although 71% of assessed cells failed to meet soil media particle-size distribution specifications, 98% of BRCs contained media with adequate or high permeability. Over half (65%) of cells were undersized vis-à-vis intended design, with 53% exhibiting moderately or severely undersized surface storage capacity. Discrepancies in average ponding depth and incorporation of inspection/maintenance programs significantly influenced the accuracy of as-built BRC storage volume; therefore, it is important for inspectors to verify that the bed elevations of BRCs have been accurately graded. Despite being typically undersized, it was concluded that most observed bioretention cells are meeting the hydrologic goals of North Carolina standards. DA - 2012/12// PY - 2012/12// DO - 10.1061/(asce)ee.1943-7870.0000575 VL - 138 IS - 12 SP - 1210-1217 SN - 0733-9372 KW - Bioretention KW - Rain garden KW - Best management practice (BMP) KW - Storm water control measure (SCM) KW - Inspection KW - Construction KW - Storm water KW - Survey KW - Maintenance ER - TY - JOUR TI - Advanced oxidation of toluene using Ni-olivine catalysts: Part 1. syntheses, characterization, and evaluation of Ni-olivine catalysts for toluene oxidation AU - Smith, V. M. AU - Kolar, P. AU - Boyette, M. D. AU - Chinn, M. AU - Smith, C. AU - Gangadharan, R. AU - Zhang, G. T2 - Transactions of the ASABE DA - 2012/// PY - 2012/// VL - 55 IS - 3 SP - 1013-1024 ER - TY - JOUR TI - A qualitative assessment tool for ecologically based stormwater systems AU - Moore, T. AU - Hutchinson, S. L. AU - Christianson, R. D. T2 - Ecological Engineering DA - 2012/// PY - 2012/// VL - 45 SP - 70-79 ER - TY - JOUR TI - A Drainmod-based method to estimate effects of drainage water management on annual nitrogen loss to surface water AU - Skaggs, R. W. AU - Youssef, M. A. AU - Chescheir, G. M. T2 - Transactions of the ASABE AB - Effects of drainage water management (DWM) on nitrogen (N) losses to surface waters can be estimated by multiplying the change in subsurface drainage and surface runoff, as predicted by DRAINMOD, by long-term mean nitrogen (N) concentration, which is a function of local site conditions (climate, soil, cropping system, farming practices, and drainage system). Consistent with experimental observations from several sources, this approximate method assumes that the effect of DWM on N losses is proportional to its effect on drainage and surface runoff volumes. The reliability of the method was evaluated by comparing estimated annual N losses for two sites (one in North Carolina and one in Illinois) to those predicted by the process-based nitrogen model DRAINMOD-NII. The long-term N concentrations used in the approximate method were based on DRAINMOD-NII predictions. DRAINMOD-NII simulations predicted that DWM would reduce long-term average N losses to surface waters by 35% for continuous corn (CC) and 33% for a corn-wheat-soybean (CWS) rotation in North Carolina and by 31% and 26% for CC and a corn-soybean (CS) rotation in Illinois. The approximate method estimated the annual effect of DWM on N losses within 3 kg ha-1 of that predicted by DRAINMOD-NII in over 68% of the years for the CWS and CS rotations at both sites and in over 51% of the years for CC. Overestimated effects in some years were balanced by underestimated effects in others. However, relatively large errors occurred in about 25% of the years when N concentrations in the drainage water varied significantly from the long-term average. These errors typically occurred following periods when crop yields deviated significantly from the average. When these outliers were excluded from the analyses, the goodness of fit between annual N losses predicted by DRAINMOD-NII and annual losses estimated by the approximate method was substantially improved (Nash-Sutcliffe EF values ranging from 0.54 to 0.79). Although more research is needed to improve the approximate method when concentrations vary significantly from the long-term average, the results presented herein indicate that the method provides a reliable means of assessing impacts of DWM under normal conditions. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41515 VL - 55 IS - 3 SP - 799-808 ER - TY - JOUR TI - KI-impregnated oyster shell as a solid catalyst for soybean oil transesterification AU - Jairam, Suguna AU - Kolar, Praveen AU - Sharma-Shivappa, Ratna AU - Osborne, Jason A. AU - Davis, Jack P. T2 - BIORESOURCE TECHNOLOGY AB - Research on inexpensive and green catalysts is needed for economical production of biodiesel. The goal of the research was to test KI-impregnated calcined oyster shell as a solid catalyst for transesterification of soybean oil. Specific objectives were to characterize KI-impregnated oyster shell, determine the effect of reaction variables and reaction kinetics. The catalyst was synthesized by impregnating KI on calcined oyster shells. X-ray diffraction analysis indicated the presence of portlandite and potassium iodide on the surface and a 31-fold increase in surface as a result of calcination and KI impregnation. Under the conditions tested, ideal reaction variables were 1 mmol g−1 for catalyst loading, 50 °C for temperature, 10:1 for methanol/oil, and 4 h for reaction time. The transesterification followed a first-order reaction (k = 0.4385 h−1). The option of using oyster shell for the production of transesterification catalysts could have economic benefits to the aquaculture industry in the US. DA - 2012/1// PY - 2012/1// DO - 10.1016/j.biortech.2011.10.039 VL - 104 SP - 329-335 SN - 1873-2976 KW - Biodiesel KW - Fatty acid methyl esters KW - Solid catalysts KW - KI-impregnated oyster shells ER - TY - JOUR TI - Improvement of Sugar Production from Transgenic Switchgrass with Low-Temperature Alkali Pretreatment AU - Wang, Ziyu AU - Xu, Jiele AU - Pandey, Pankaj AU - Cheng, Jay J. AU - Li, Ruyu AU - Qu, Rongda T2 - ENERGY & FUELS AB - Genetically modified switchgrass (cv. Alamo) and its conventional plant were both pretreated using two groups of conditions: lime at 50 °C and the combination of lime and NaOH at ambient temperature. The results show that the transgenic plant (with altered lignin content and composition) was more susceptible to alkali pretreatment than the conventional plant. At the recommended conditions (0.1 g/g of raw biomass and 12 h) for lime pretreatment at 50 °C, the glucan and xylan conversions of transgenic switchgrass were 12 and 10%, respectively, higher than those of the conventional plant. These increases were reduced to 7 and 8% for glucan and xylan conversions, respectively, when the best conditions (0.025 g of lime/g of raw biomass, 0.1 g of NaOH/g of raw biomass, and 6 h) for combined alkali pretreatment at ambient temperature were employed. The advantage of transgenics over a conventional plant in sugar production could be maximized if proper pretreatment conditions were used. DA - 2012/5// PY - 2012/5// DO - 10.1021/ef3004575 VL - 26 IS - 5 SP - 3054-3061 SN - 1520-5029 ER - TY - JOUR TI - Dilute sulfuric acid pretreatment of transgenic switchgrass for sugar production AU - Zhou, Xu AU - Xu, Jiele AU - Wang, Ziyu AU - Cheng, Jay J. AU - Li, Ruyu AU - Qu, Rongda T2 - BIORESOURCE TECHNOLOGY AB - Conventional Alamo switchgrass and its transgenic counterparts with reduced/modified lignin were subjected to dilute sulfuric acid pretreatment for improved sugar production. At 150 °C, the effects of acid concentration (0.75%, 1%, 1.25%) and residence time (5, 10, 20, 30 min) on sugar productions in pretreatment and enzymatic hydrolysis were investigated, with the optimal pretreatment conditions determined for each switchgrass genotype based on total sugar yield and the amounts of sugar degradation products generated during the pretreatment. The results show that genetic engineering, although did not cause an appreciable lignin reduction, resulted in a substantial increase in the ratio of acid soluble lignin:acid insoluble lignin, which led to considerably increased sugar productions in both pretreatment and enzymatic hydrolysis. At an elevated threshold concentration of combined 5-hydroxyfuranmethal and furfural (2.0 g/L), the overall carbohydrate conversions of conventional switchgrass and its transgenic counterparts, 10/9-40 and 11/5-47, reached 75.9%, 82.6%, and 82.2%, respectively. DA - 2012/1// PY - 2012/1// DO - 10.1016/j.biortech.2011.11.051 VL - 104 SP - 823-827 SN - 0960-8524 KW - Acid pretreatment KW - Genetic engineering KW - Lignin KW - Sugars KW - Switchgrass ER - TY - JOUR TI - Comparison of Body Weight Distribution, Peak Vertical Force, and Vertical Impulse as Measures of Hip Joint Pain and Efficacy of Total Hip Replacement AU - Seibert, Rachel AU - Marcellin-Little, Denis J. AU - Roe, Simon C. AU - DePuy, Venita AU - Lascelles, B. Duncan X. T2 - VETERINARY SURGERY AB - Objective To determine whether there is a difference between the ability of peak vertical force ( PVF ), vertical impulse ( VI ), and percentage body weight distribution (% BW dist ) in differentiating which leg is most affected by hip joint pain before total hip replacement ( THR ) surgery, and for measuring changes in limb use after THR surgery. Study Design Prospective clinical study. Animals Dogs (n = 47). Methods Ground reaction force ( GRF ) data were collected using a pressure‐sensitive walkway the day before THR surgery and at ∼3, 6, and 12 months postoperatively. PVF and VI expressed as a percentage of body weight (% PVF , % VI ), and % BW dist were recorded. Regression models performed separately for each outcome were used for statistical analysis. Results When comparing limb use between the affected limb ( AP ) and the nonaffected limb ( NP ) preoperatively, differences between limbs were statistically significant when evaluated using PVF ( P = .023), VI ( P = .010), and % BW dist ( P = .012). When evaluating the magnitude of absolute and percentage change difference in AP limb use preoperatively versus postoperatively, differences were statistically significant when evaluated using PVF ( P < .001 and P = .001, respectively), VI ( P = .001 and P < .001) and % BW dist ( P < .001 and P < .001). Conclusion There appeared to be no difference in the sensitivity of VI , PVF , and % BW dist for evaluating limb use before and after THR . DA - 2012/5// PY - 2012/5// DO - 10.1111/j.1532-950x.2012.00957.x VL - 41 IS - 4 SP - 443-447 SN - 0161-3499 ER - TY - JOUR TI - Water Quality of Drainage from Permeable Friction Course AU - Eck, Bradley J. AU - Winston, Ryan J. AU - Hunt, William F. AU - Barrett, Michael E. T2 - JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE AB - An overlay of porous asphalt known as permeable friction course (PFC) is an innovative roadway material that improves both driving conditions in wet weather and water quality. Placed in a layer 25–50 mm thick on top of regular impermeable pavement, PFC allows rainfall to drain within the porous layer rather than on top of the pavement. This paper presents water quality measurements for PFC and conventional pavement collected over six years near Austin, TX and two years in eastern North Carolina. The data show that concentrations of total suspended solids from PFC are more than 90% lower than from conventional pavement. Lower effluent concentrations are also observed for total amounts of phosphorus, copper, lead, and zinc. The combined data sets show that PFC’s benefits last through the design life of the pavement, that results in Texas are consistent with those from North Carolina, and that both are consistent with earlier studies from France, the Netherlands, and Germany. DA - 2012/2// PY - 2012/2// DO - 10.1061/(asce)ee.1943-7870.0000476 VL - 138 IS - 2 SP - 174-181 SN - 0733-9372 KW - Highway runoff KW - Field monitoring KW - Permeable friction course KW - Stormwater ER - TY - JOUR TI - Quantification of emission factor uncertainty AU - Pouliot, George AU - Wisner, Emily AU - Mobley, David AU - Hunt, William, Jr. T2 - JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION AB - Emissions factors are important for estimating and characterizing emissions from sources of air pollution. There is no quantitative indication of uncertainty for these emission factors, most factors do not have an adequate data set to compute uncertainty, and it is very difficult to locate the data for those that do. The objectives are to compare the current emission factors of Electric Generating Unit NOX sources with currently available continuous emission monitoring data, develop quantitative uncertainty indicators for the Environmental Protection Agency (EPA) data quality rated emission factors, and determine the possible ranges of uncertainty associated with EPA's data quality rating of emission factors. EPA's data letter rating represents a general indication of the robustness of the emission factor and is assigned based on the estimated reliability of the tests used to develop the factor and on the quantity and representativeness of the data. Different sources and pollutants that have the same robustness in the measured emission factor and in the representativeness of the measured values are assumed to have a similar quantifiable uncertainty. For the purposes of comparison, we assume that the emission factor estimates from source categories with the same letter rating have enough robustness and consistency that we can quantify the uncertainty of these common emission factors based on the qualitative indication of data quality which is known for almost all factors. The results showed that EPA's current emission factor values for NOX emissions from combustion sources were found to be reasonably representative for some sources; however, AP-42 values should be updated for over half of the sources to reflect current data. The quantified uncertainty ranges were found to be 25–62% for A rated emission factors, 45–75% for B rated emission factors, 60–82% for C rated emission factors, and 69–86% for D rated emission factors, and 82–92% for E rated emission factors. Implications Currently, a letter grade indicates the data quality uncertainty of emission factors in EPA's Compilation of Emission Factors (AP-42). However, a quantitative characterization would be much preferred. If the uncertainty of emission factors is quantified, scientists may be able to more accurately characterize the uncertainty associated with air quality modeling and emission data. A quantitative measure of uncertainty will also give decision makers the ability to determine the confidence that should be placed in the analysis of the data being used for policy decisions. DA - 2012/3// PY - 2012/3// DO - 10.1080/10473289.2011.649155 VL - 62 IS - 3 SP - 287-298 SN - 2162-2906 ER - TY - JOUR TI - Meeting Hydrologic and Water Quality Goals through Targeted Bioretention Design AU - Hunt, William F. AU - Davis, Allen P. AU - Traver, Robert G. T2 - JOURNAL OF ENVIRONMENTAL ENGINEERING AB - Bioretention is one of the most commonly used stormwater control measures (SCMs) in North America and Australasia. However, current design is not targeted to regulatory need, often reflecting an outdated understanding of how and why bioretention works. The purpose of this manuscript is to synthesize research to recommend a suite of design standards focused on the purpose of bioretention SCM. Both hydrologic (peak flow mitigation, infiltration, annual hydrology, and stream stability) and water quality [total suspended solids (TSS) and particulates, pathogen-indicator species, metals, hydrocarbons, phosphorus, nitrogen, and temperature] regulatory and stream ecology needs are addressed. Bioretention cells designed to meet a prioritized subset of those measures would be substantially different than cells that are designed for a different subset of needs. Designers have the ability to adjust bowl volume, media composition, media depth, underdrainage configuration, and vegetation type. This study examines how each of those design parameters can be adjusted such that a “one size fits all” approach is no longer the norm. DA - 2012/6// PY - 2012/6// DO - 10.1061/(asce)ee.1943-7870.0000504 VL - 138 IS - 6 SP - 698-707 SN - 1943-7870 KW - Stormwater KW - Infiltration KW - Bioretention KW - Hydrology KW - Water quality KW - Design KW - Pathogens KW - Temperature KW - Nutrients KW - Bioinfiltration ER - TY - JOUR TI - LID Treatment Train: Pervious Concrete with Subsurface Storage in Series with Bioretention and Care with Seasonal High Water Tables AU - Brown, R. A. AU - Line, D. E. AU - Hunt, W. F. T2 - JOURNAL OF ENVIRONMENTAL ENGINEERING AB - Two infiltrating low-impact development (LID) practices configured in-series, pervious concrete and bioretention (PC-B), were monitored for 17 months to examine the hydrologic and water quality response of this LID treatment train design. For the first LID practice, 0.53 ha of pervious concrete was installed to treat direct rainfall and run-on from 0.36 ha of asphalt parking lot. The pervious concrete was installed over a gravel subsurface storage basin, which was designed to store 25 mm (1 in.) of runoff from the parking lot before draining into the second LID practice, which was a 0.05 ha bioretention cell. The bioretention cell was conventionally drained, had a media depth of 0.5 m (1.6 ft), and was constructed at a location with a high water table. Outflow was only generated in 33 out of 80 monitored events, and over the course of the entire monitoring period, the total outflow volume reduction was 69%. The large outflow reduction subsequently led to high pollutant load reductions for total nitrogen (49%), total phosphorus (51%), and total suspended solids (89%). However, when the contribution of base flow was included in the calculation, the total nitrogen load discharged from the bioretention cell was 64% higher than that of the runoff load because of nitrite and nitrate, NO2- and NO3-(NO2,3-N), which were present in the base flow. The total nitrogen (TN) loads of runoff, storm flow (total outflow minus base flow), base flow, and outflow (total) were 7.70, 3.94, 8.69, and 12.64 kg/ha·year, respectively. Of the 8.69 kg/ha·year TN in the base flow, 92% was in the form of NO2,3-N. This study demonstrated the hydrologic benefits (peak flow and outflow reduction) gained by having two infiltration LID practices in-series. When compared with a single treatment practice (bioretention) that was monitored at the same site, the two LID practices in-series treated an additional 10% of annual runoff volume, discharged approximately one-half as much outflow volume, and discharged significantly lower peak outflow rates. However, the water quality results were not as promising because of the influx of groundwater in the bioretention cell and the lack of denitrifying conditions in either the bioretention cell or pervious concrete system. This study also quantified increased TN and NO2,3-N export to surface waters from a bioretention cell that was situated in an area with a high water table. DA - 2012/6// PY - 2012/6// DO - 10.1061/(asce)ee.1943-7870.0000506 VL - 138 IS - 6 SP - 689-697 SN - 1943-7870 KW - Storm water management KW - Low-impact development KW - Storm water control measure KW - Permeable pavement KW - Water quality KW - Hydrology KW - Peak flow reduction KW - Intercepted water table ER - TY - JOUR TI - Field evaluation of particulate matter measurements using tapered element oscillating microbalance in a layer house AU - Li, Qian-Feng AU - Wang-Li, Lingjuan AU - Liu, Zifei AU - Heber, Albert J. T2 - JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION AB - The tapered element oscillating microbalance (TEOM) is one type of continuous ambient particulate matter (PM) monitor. Adsorption and desorption of moisture and semivolatile species may cause positive or negative artifacts in TEOM PM mass measurement. The objective of this field study was to investigate possible uncertainties associated with TEOM measurements in the poultry operation environment. For comparisons of TEOM with filter-based gravimetric method, four instruments (TEOM-PM10, low-volume PM10 sampler, TEOM-PM2.5, and PM2.5 speciation sampler) were collocated and tested inside a poultry house for PM2.5 and PM10 (PM with aerodynamic equivalent diameter ≤2.5 and ≤10 μm, respectively) measurements. Fifteen sets of 24-hr PM10 concentrations and 13 sets of 24-hr PM2.5 measurements were obtained. Results indicate that compared with filter-based gravimetric method, TEOM gave significantly lower values of both PM10 and PM2.5 mass concentrations. For PM10, the average ratio of TEOM to the gravimetric method was 0.936. For PM2.5, the average ratio of TEOM to the gravimetric method was 0.738. Particulate matter in the poultry houses possibly contains semivolatile compounds and moisture due to high levels of relative humidity (RH) and gas pollutants. The internal heating mechanism of the TEOM may cause losses in mass through volatilization. To investigate the effects of TEOM settings on concentration measurements, the heaters of two identical TEOMs were set at 50 °C, 30 °C, or no heating at all. They were collocated and tested for total suspended particle (TSP), PM10, and PM2.5 measurements in layer house for 6 weeks. For all TSP, PM10, and PM2.5 measurements, the internal TEOM temperature setting had a significant effect (P < 0.05). Significantly higher PM mass concentrations were measured at lower temperature settings. The effects of environmental (i.e., temperature, RH, NH3 and CO2 concentrations) and instrumental (i.e., filter loading and noise) parameters on PM measurements were also assessed using regression analysis. Implications Because of its potential health and environmental effects, particulate matter (PM) emissions from animal feeding operations (AFOs) have been a great concern to the public and to the regulatory agencies. The tapered element oscillating microbalance (TEOM) PM monitor has been was adapted for continuous PM measurements in some AFO air quality studies. This study investigated possible uncertainties associated with TEOM measurements in an egg production environment. It was discovered that there was a significant bias in TEOM measurements of PM10 as compared with federal reference method. Internal temperature settings of a TEOM have significant impact on its PM measurement. DA - 2012/3// PY - 2012/3// DO - 10.1080/10473289.2011.650316 VL - 62 IS - 3 SP - 322-335 SN - 2162-2906 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84860252608&partnerID=MN8TOARS ER - TY - JOUR TI - Factors affecting uniformity of irrigation-type manure application systems AU - Liu, Z. AU - Grabow, G. L. AU - Huffman, R. L. AU - Osborne, J. AU - Evans, R. O. T2 - Applied Engineering in Agriculture AB - Liquid manure is usually treated through application to agricultural land using irrigation systems. Land application of liquid manure needs to follow established guidelines in order to achieve economic goals as well as to protect the environment. Guidance at the time of this study in North Carolina suggested calibration of land application equipment be performed once every three years by the catch can method, a time- and labor-consuming method. The goals of this project were to investigate the relationship between liquid manure application uniformity by using data from historical uniformity assessment trials and from additional trials conducted during the study, and to use the results to provide guidance in developing a simplified field method for uniformity assessment. Trials were performed to test the liquid manure application uniformity for different irrigation system types, sprinkler types and models, nozzle types, nozzle diameters, and nozzle pressures. Wind speed during the trials was monitored. Different sprinkler overlaps were achieved by superposition, thereby allowing for assessment of multiple sprinkler spacings for each trial. Regression models were constructed using historic and study-period trial data and a process of main effect selection, collinearity checking, interaction term and quadratic term selection, parameter estimation, and normality testing of model residuals. The model for stationary systems performed well with an adjusted R2 of 0.72 and predicted application uniformity showed the expected tendencies with changes in predictive factors. The model for traveling gun systems did not perform as well as that for stationary systems; the adjusted R2 was only 0.33. The results of this study were used to amend uniformity assessment requirements to a simple procedure requiring measurement of sprinkler nozzle pressure, wetted diameter, and sprinkler spacing. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41285 VL - 28 IS - 1 SP - 43-56 ER - TY - JOUR TI - Efficient temperature control in recirculating aquaculture tanks AU - Saidu, M.M. AU - Hall, S.G. AU - Kolar, P. AU - Schramm, R. AU - Davis, T. T2 - Applied Engineering in Agriculture AB - Improving process control in recirculating aquaculture systems can reduce start-up and maintenance costs and increase the effectiveness of operations. Efficient control of temperature in recirculating systems may increase energy savings, improve productivity, and enhance sustainability. This study focused on cost-effective design, installation, and determination of heat transfer efficiency in small recirculating tank systems. A series of low-cost in-situ coil heat exchangers were developed and used to maintain desired operational temperatures via computer process control for several independent recirculating aquaculture systems. However no fish were in the tanks during preliminary testing. Knowledge of the functional heat transfer capability of such systems is necessary for effective design. The computerized process control system was coupled with controlled low-cost in-situ chillers and glass insertion heaters to impose desired temperature regimes in independent tanks. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41269 VL - 28 IS - 1 SP - 161-167 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84859710421&partnerID=MN8TOARS ER - TY - JOUR TI - Effectiveness of LID for commercial development in North Carolina T2 - Journal of Environmental Engineering (New York, N.Y.) DA - 2012/// PY - 2012/// VL - 138 IS - 6 SP - 680-688 ER - TY - JOUR TI - Subsurface drip irrigation: Status of the technology in 2010 AU - Lamm, F. R. AU - Bordovsky, J. P. AU - Schwankl, L. J. AU - Grabow, G. L. AU - Enciso-Medina, J. AU - Peters, R. T. AU - Colaizzi, P. D. AU - Trooien, T. P. AU - Porter, D. O. T2 - Transactions of the ASABE AB - Subsurface drip irrigation (SDI), although a much smaller fraction of the microirrigated land area than surface drip irrigation, is growing at a much faster rate and is the subject of considerable research and educational efforts in the U.S. This article discusses the growth of SDI, highlights some of the research and extension efforts, and points out some of the challenges to SDI adoption and some of the future opportunities for SDI. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41387 VL - 55 IS - 2 SP - 483-491 ER - TY - JOUR TI - Influence of patch size and shape on occupancy by shrubland birds AU - Shake, C. S. AU - Moorman, C. E. AU - Riddle, J. D. AU - Burchell, M. R. T2 - Condor DA - 2012/// PY - 2012/// VL - 14 IS - 2 SP - 268-278 ER - TY - JOUR TI - Hydrologic Performance of Bioretention Storm-Water Control Measures AU - Davis, Allen P. AU - Traver, Robert G. AU - Hunt, William F. AU - Lee, Ryan AU - Brown, Robert A. AU - Olszewski, Jennifer M. T2 - JOURNAL OF HYDROLOGIC ENGINEERING AB - The transportation and urban infrastructure relies heavily on impervious surfaces. Unmitigated rainfall runoff from impervious surfaces can lead to a myriad of environmental problems in downgradient areas. To address this issue, novel stormwater control measures (SCMs) are being emphasized and implemented widely to mitigate some of the impacts of impervious surface. Bioretention is a soil/media-based SCM that is often used for this purpose, but current design practices are highly empirical. This study compiles work from three research sites in three states to provide some fundamental underpinnings to bioretention design. Although all sites demonstrate different levels of performance, water volumetric performance trends are common to all. These trends are based on the available storage in the bioretention cell, termed herein as the Bioretention Abstraction Volume (BAV). The BAV is directly related to available media porosity and storage in the surface bowl. A finite capacity to completely store all runoff from smaller events is defined by the BAV. Normalization for this storage provides prediction for volumetric performance. Recommendations for bioretention design are provided. DA - 2012/5// PY - 2012/5// DO - 10.1061/(asce)he.1943-5584.0000467 VL - 17 IS - 5 SP - 604-614 SN - 1084-0699 KW - Stormwater KW - Runoff KW - Urban KW - Hydrology. ER - TY - JOUR TI - Ethanol production from alkali- and ozone-treated cotton stalks using thermotolerant Pichia kudriavzevii HOP-1 AU - Kaur, Ujjal AU - Oberoi, Harinder Singh AU - Bhargav, Vinod Kumar AU - Sharma-Shivappa, Ratna AU - Dhaliwal, Sandeep Singh T2 - INDUSTRIAL CROPS AND PRODUCTS AB - In the present study, milled cotton stalks were subjected to alkali pretreatment with NaOH at 1–4% (w/v) concentrations at 121 °C for time ranging from 30 to 90 min. Ozone pretreatment was performed by passing 45 mg/L of ozone gas over 2 mm cotton stalks for 150 min at a flow rate of 0.37 L/min. The residual biomass from 4% alkali pretreatment for 60 min showed 46.6% lignin degradation accompanied by 83.2% increase in glucan content, compared with the untreated biomass. Hydrolysis of 4% alkali-treated and ozone-treated cotton stalks was conducted using enzyme combination of 20 filter paper cellulase units/gram dried substrate (FPU/g-ds), 45 IU/g-ds β-glucosidase and 15 IU/g-ds pectinase. Enzymatic hydrolysis of alkali-treated and ozone-treated biomass after 48 h resulted in 42.29 g/L glucose, 6.82 g/L xylose and 24.13 g/L glucose, 8.3 g/L xylose, respectively. About 99% of glucose was consumed in 24 h by Pichia kudriavzevii HOP-1 cells resulting in 19.82 g/L of ethanol from alkali-treated cotton stalks and 10.96 g/L of ethanol from ozone-treated cotton stalks. Simultaneous saccharification and fermentation of the alkali-treated cotton stalks after 12-h pre-hydrolysis resulted in ethanol concentration, ethanol yield on dry biomass basis and ethanol productivity of 19.48 g/L, 0.21 g/g and 0.41 g/L/h, respectively which holds promise for further scale-up studies. To the best of our knowledge, this is the first study employing SSF for ethanol production from cotton stalks. DA - 2012/5// PY - 2012/5// DO - 10.1016/j.indcrop.2011.12.007 VL - 37 IS - 1 SP - 219-226 SN - 1872-633X KW - Sodium hydroxide pretreatment KW - Cotton stalks KW - Enzymatic hydrolysis KW - Delignification KW - Ozone pretreatment, Pichia kudriavzevii KW - HOP-1 ER - TY - JOUR TI - Chemical and elemental composition of big bluestem as affected by ecotype and planting location along the precipitation gradient of the Great Plains AU - Zhang, Ke AU - Johnson, Loretta AU - Nelson, Richard AU - Yuan, Wenqiao AU - Pei, Zhijian AU - Wang, Donghai T2 - INDUSTRIAL CROPS AND PRODUCTS AB - Three big bluestem ecotypes from central Kansas (Cedar Bluffs and Webster populations), eastern Kansas (Konza and Top of the World populations), and Illinois (12Mile and Fults populations), as well as the Kaw cultivar, were harvested from four reciprocal garden planting locations (Colby, Hays, and Manhattan, KS; and Carbondale, IL) and evaluated for their chemical (glucan, xylan, arabinan, lignin and ash) and elemental (carbon, oxygen, hydrogen, nitrogen and sulfur) compositions. The objective of this research was to study the effects of ecotype and planting location on the chemical and elemental compositions of big bluestem along the Great Plains precipitation gradient (∼1200 to 400 mm mean annual precipitation). All the populations revealed a large variation in cellulose (31.8–36.5%), hemicellulose (24.96–29.74%), lignin (14.4–18.0%), carbon (47.3–51.3%), and nitrogen (4.91–6.44%). Planting location had significant effects on both chemical and elemental compositions of big bluestem. Ecotype had significant effects on glucan, xylan, lignin, and ash contents as well as on carbon, oxygen, and hydrogen elemental fractions. In addition, the interaction between ecotype and planting location had significant effects on glucan, lignin, and hydrogen. Planting location had a greater effect on chemical and elemental compositions than the ecotype and interaction between location and ecotype. The total sugar content of the big bluestem (regardless of ecotype) increased as the Great Plains precipitation gradient increased from west to east. Annual precipitation, growing degree days and potential evapotranspiration in 2010 explained up to 97%, 88% and 80% of the variation in compositions, respectively. DA - 2012/11// PY - 2012/11// DO - 10.1016/j.indcrop.2012.03.016 VL - 40 SP - 210-218 SN - 1872-633X KW - Big bluestem KW - Chemical composition KW - Elemental composition KW - Ecotype KW - Reciprocal common garden ER - TY - JOUR TI - Nutrient removal from swine wastewater by growing duckweed: A pilot study AU - Xu, J. AU - Cheng, Jay AU - Stomp, A. M. T2 - Transactions of the ASABE AB - A pilot-scale duckweed pond was installed and integrated into the existing swine wastewater management system of a swine farm in Zebulon, North Carolina to investigate its effectiveness in removing nutrients from anaerobically treated swine wastewater. The nutrient-rich wastewater was added intermittently into the duckweed pond to maintain an ammonium (NH4-N) concentration of about 20 mg L-1, and the duckweed was harvested regularly to ultimately remove nutrients from the water body. The results show that duckweed (Spirodela polyrrhiza) grew rapidly on swine wastewater under field conditions, with a dry biomass yield of 10.7 g m-2 d-1 in August and September. Over the 16-week experimental period, NH4-N, the major nutrient concern in swine wastewater, was removed at 1.12 g m-2 d-1. The fast duckweed growth and an average duckweed protein content of 26.3% enabled a protein yield of 2.11 g m-2 d-1 throughout the experiment. DA - 2012/// PY - 2012/// DO - 10.13031/2013.41264 VL - 55 IS - 1 SP - 181–185 ER - TY - JOUR TI - Indicator Bacteria Performance of Storm Water Control Measures in Wilmington, North Carolina AU - Hathaway, J. M. AU - Hunt, W. F. T2 - JOURNAL OF IRRIGATION AND DRAINAGE ENGINEERING AB - Indicator bacteria are a common source of impairment in surface waters in the United States. Urban storm water runoff has been identified as a contributor to elevated indicator bacteria concentrations. Six storm water control measures (SCMs) were monitored in Wilmington, North Carolina, for E. coli and enterococci. Monitored SCMs included two storm water wet ponds, two bioretention cells, and two storm water wetlands. Sandier watersheds in Wilmington potentially lead to differences in SCM performance for indicator bacteria compared to SCMs implemented in clayey watersheds. Results showed E. coli and enterococci concentration reductions between 70 and 98% for the two wet ponds and a bioretention cell with a 60-cm-deep fill media. Other SCMs showed poor removal of indicator bacteria, in some cases negative, with storm water wetlands performing the poorest overall for the three SCM types. Further analysis showed that SCMs with high concentration reductions tended to have geometric mean effluent concentrations lower than the U.S. EPA’s target surface-water concentration for E. coli. Conversely, no SCM had a geometric mean effluent enterococci concentration lower than the U.S. EPA target value. SCM geometric mean effluent concentrations were typically higher during North Carolina’s swimming season between the beginning of April and the end of October, although no statistically significant relationship could be found (p<0.05). Despite a lack of statistically significant relationships, the potential for higher effluent indicator bacteria concentrations from SCMs during the peak recreational season may have implications for both public health and watershed management and should be further evaluated by the scientific community. DA - 2012/2// PY - 2012/2// DO - 10.1061/(asce)ir.1943-4774.0000378 VL - 138 IS - 2 SP - 185-197 SN - 1943-4774 KW - Storm water KW - Best management practice (BMP) KW - Indicator bacteria KW - Fecal coliform KW - E. coli KW - Enterococci KW - Storm water control measure (SCM) ER - TY - JOUR TI - Gel-Based Self-Propelling Particles Get Programmed To Dance AU - Sharma, Rachita AU - Chang, Suk Tai AU - Velev, Orlin D. T2 - LANGMUIR AB - We present a class of gel-based self-propelling particles moving by the Marangoni effect in an oscillatory mode. The particles are made of an ethanol-infused polyacrylamide hydrogel contained in plastic tubing. These gel boats floating on the water surface exhibit periodic propulsion for several hours. The release of ethanol from the hydrogel takes place beneath the liquid surface. The released ethanol rises to the air–water interface by buoyancy and generates a self-sustained cycle of surface tension gradient driven motion. The disruption of the ethanol flux to the surface by the bulk flows around the moving particle results in their pulsating motion. The pulse interval and the distance propelled in a pulse by these gel floaters were measured and approximated by simple expressions based on the rate of ethanol mass-transfer through and out of the hydrogel. This allowed us to design a multitude of particles performing periodic steps in different directions or at different angles of rotation, traveling in complex preprogrammed trajectories on the surface of the liquid. Similar gel-based self-propelling floaters can find applications as mixers and cargo carriers in lab-on-a-chip devices, and in various platforms for sensing and processing at the microscale. DA - 2012/6/3/ PY - 2012/6/3/ DO - 10.1021/la301437f VL - 28 IS - 26 SP - 10128-10135 SN - 0743-7463 ER - TY - JOUR TI - Sensitivity analysis of the DRAINWAT model applied to an agricultural watershed in the lower coastal plain, North Carolina, USA AU - Kim, Hyunwoo AU - Amatya, Devendra M. AU - Broome, Stephen W. AU - Hesterberg, Dean L. AU - Choi, Minha T2 - WATER AND ENVIRONMENT JOURNAL AB - Abstract The DRAINWAT , DRAINmod for WATershed model, was selected for hydrological modelling to obtain water table depths and drainage outflows at O pen G rounds F arm in C arteret C ounty, N orth C arolina, USA . Six simulated storm events from the study period were compared with the measured data and analysed. Simulation results from the whole study period and selected rainfall events assured that the DRAINWAT model reasonably predicted the water table depths and drainage outflow events even though it underestimated outflows in very dry period after 24 A pril, 2001. The potential evapotranspiration by various calculation methods was found to be the most sensitive parameter in this study. The other three parameters (maximum surface depressional storage, M anning's channel roughness coefficient, and channel bedslope) were not significantly ( α = 0.05) sensitive to the cumulative outflow as expected. The DRAINWAT model may be a useful tool for water management in flat agricultural areas with high water table if it can be calibrated properly with reliable measurements. DA - 2012/3// PY - 2012/3// DO - 10.1111/j.1747-6593.2011.00283.x VL - 26 IS - 1 SP - 130-145 SN - 1747-6585 KW - agricultural water management KW - bedslope KW - drainage outflow KW - DRAINWAT KW - Manning's roughness coefficient KW - potential evapotranspiration KW - surface depressional storage KW - water table depth ER - TY - JOUR TI - Resistance to Subsidence of an Uncemented Femoral Stem After Cerclage Wiring of a Fissure AU - McCulloch, Ryan S. AU - Roe, Simon C. AU - Marcellin-Little, Denis J. AU - Mente, Peter L. T2 - VETERINARY SURGERY AB - To compare: (1) the force required to initiate subsidence, and (2) the relative subsidence, of femoral stems implanted into intact femora, and then into the same femora in which an induced fissure had been stabilized by cerclage.In vitro, mechanical study.Femora (n=9) from 9 dogs.Femora were prepared for implantation of an uncemented stem. Stems were implanted with continuous and impact loading. After axial loading until a fissure occurred, the stems were extracted, and the fissure stabilized with double-loop cerclage. Stems were reimplanted, and reloaded to failure.Mean±SD load to initiate subsidence in intact femora was 1706±584 N compared with 2379±657 N for cerclaged bones (P=.002). Mean relative subsidence of intact femora was 3.99±2.09 mm compared with 1.79±2.99 mm for cerclaged bones (P=.091).The load to initiate subsidence is increased in femora that have fissured, then have been stabilized with double-loop cerclage, when compared with intact femora. The relative subsidence is not different between intact and stabilized specimens. DA - 2012/1// PY - 2012/1// DO - 10.1111/j.1532-950x.2011.00858.x VL - 41 IS - 1 SP - 163-167 SN - 0161-3499 ER - TY - JOUR TI - Pretreatment of corn stover for sugar production with switchgrass-derived black liquor AU - Xu, Jiele AU - Zhang, Ximing AU - Cheng, Jay J. T2 - BIORESOURCE TECHNOLOGY AB - To improve the cost-effectiveness of biomass-to-sugar conversion, sodium hydroxide (NaOH) pretreatment of switchgrass was carried out at 21°C using previously determined optimum conditions (2% NaOH (w/v), 6h), and the spent alkaline liquid (black liquor) was collected and used for pretreatment of corn stover, a feedstock exhibiting a higher susceptibility to NaOH attack, for improved enzymatic hydrolysis at a reduced cost. The results showed that, because of the high pH and the appreciable amount of carbohydrates in the black liquor, sugar production during enzymatic hydrolysis of corn stover pretreated with black liquor was comparable to that of biomass pretreated with 1% NaOH. After black liquor pretreatment at the best residence time (24h), the total reducing sugar, glucose, and xylose yields of corn stover reached 478.5, 287.7, and 145.3mg/g raw biomass, respectively, indicating the viability of this novel pretreatment technology. DA - 2012/5// PY - 2012/5// DO - 10.1016/j.biortech.2012.02.006 VL - 111 SP - 255-260 SN - 1873-2976 KW - Alkaline pretreatment KW - Black liquor KW - Corn stover KW - Sodium hydroxide KW - Switchgrass ER - TY - JOUR TI - Hydrocarbon fuels from vegetable oils via hydrolysis and thermo-catalytic decarboxylation AU - Wang, Wei-Cheng AU - Thapaliya, Nirajan AU - Campos, Andrew AU - Stikeleather, Larry F. AU - Roberts, William L. T2 - FUEL AB - Conversion of canola oil to normal alkane hydrocarbons was investigated using sequential reactions: continuous thermal hydrolysis and fed-batch thermo-catalytic decarboxylation. The free fatty acid (FFA) intermediate product from hydrolysis was quantified using GC–FID, which showed 99.7% conversion and the following components: palmitic, oleic, linoleic, linolenic, stearic, arachidic and behenic acids. The FFA was saturated then decarboxylated at an average rate of 15.5 mmoles/min using a 5% Pd/C catalyst at 300 °C. Approximately 90% decarboxylation conversion to n-alkanes was achieved within 5 h of the reaction. The resulting mixture of n-alkanes can be readily converted into renewable diesel using isomerization to improve the cold flow properties of the fuel. DA - 2012/5// PY - 2012/5// DO - 10.1016/j.fuel.2011.12.041 VL - 95 IS - 1 SP - 622-629 SN - 1873-7153 KW - Biofuel production KW - Free fatty acid KW - Hydrocarbon fuels KW - Hydrolysis KW - Deoxygenation ER - TY - JOUR TI - Evaluation of additive for reducing gaseous emissions from swine waste AU - Shah, Sanjay B. AU - Kolar, Praveen T2 - Agricultural Engineering International: CIGR Journal DA - 2012/// PY - 2012/// VL - 14 IS - 2 SP - 10-20 ER - TY - JOUR TI - Field Evaluation of Storm-Water Control Measures for Highway Runoff Treatment AU - Winston, Ryan J. AU - Hunt, William F. AU - Kennedy, Shawn G. AU - Wright, Jason D. AU - Lauffer, Matthew S. T2 - JOURNAL OF ENVIRONMENTAL ENGINEERING AB - The thousands of kilometers of highways in North Carolina have the potential to generate large amounts of storm-water runoff. Thus, investigation of storm-water control measures (SCMs) for these somewhat unique linear catchments, where space is limited for SCM implementation, was needed. This study examined the quantity and quality of highway runoff at four sites over a 48-km stretch of Interstate 40 in the coastal plain of North Carolina. The highway had a 4-cm overlay of permeable asphalt, known as permeable friction course (PFC), which influenced the export of sediment-bound pollutants and produced median effluent concentrations of total suspended solids (TSS) of 8 mg/L, 8 mg/L, 9 mg/L, and 17 mg/L at the four sites, well below concentrations observed from standard asphalt highway runoff. Two vegetative filter strips (VFSs), two traditional dry swales, and two wetland swales were also tested for pollutant removal efficacy at the four highway research sites. The filter strips generally produced higher pollutant concentrations than the edge of pavement due to a lack of vegetative cover, substantial soil compaction, and high slopes. Total nitrogen (TN) median effluent concentrations were significantly lower for wetland swales (1.02 mg/L and 1.03 mg/L) than for dry swales (1.50 mg/L and 1.63 mg/L). TN load export appeared lower from wetland swales when compared with dry swales, potentially due to the greater number of nutrient removal mechanisms that are present in wetland swales. Maintenance of highway SCMs was shown to be extremely important, as one of the dry swales produced an effluent TSS concentration of 70 mg/L due to a head cut in the thalweg of the channel. As noted in other scientific literature, vegetative SCMs did not further reduce pollutant concentrations released by the PFC because TSS and sediment-bound pollutant concentrations seemingly were at or near irreducible concentrations. This study showed that incorporating wetland elements in the design of swales and the use of PFC should be considered by roadway designers. DA - 2012/1// PY - 2012/1// DO - 10.1061/(asce)ee.1943-7870.0000454 VL - 138 IS - 1 SP - 101-111 SN - 1943-7870 KW - Storm water KW - Highway runoff KW - Permeable friction course KW - Dry swale KW - Wetland swale KW - Filter strip KW - Nitrogen KW - Phosphorus KW - Sediment ER - TY - JOUR TI - Processing of materials derived from sweet sorghum for biobased products AU - Whitfield, Matthew B. AU - Chinn, Mari S. AU - Veal, Matthew W. T2 - INDUSTRIAL CROPS AND PRODUCTS AB - Sweet sorghum (Sorghum bicolor (L.) Moench) is particularly suitable as a feedstock for a variety of bioprocesses, largely because of its high yields of both lignocellulosic biomass and fermentable saccharides. Sweet sorghum is less economically important for refined sugar production than other sugar crops, e.g., sugar beet and sugarcane, but can produce more raw fermentable sugar under marginal conditions than those crops. In this review, the agronomic requirements of sorghum (viz., water, soil, and nutrient requirements), cultural practices, and plant morphology are discussed from a bioprocessing perspective. Historically, sugar extraction from the plant in the form of juice has been of primary interest; these methods, along with modern developments are presented. Recently, the direct yeast fermentation of sorghum juice for ethanol production has been studied. Additionally, the bagasse resulting from the juice extraction has been used for a variety of potential products: forage, silage, combustion energy, synthesis gas, and paper. The bagasse contains high levels of relatively low crystallinity cellulose, along with relatively labile lignin, and so is itself of interest as a fermentation feedstock. Whole sorghum stalk, and its bagasse, have been subjected to studies of a wide array of pretreatment, enzymatic hydrolysis, and fermentation processes. The potential fermentation products of sweet sorghum are wide ranging; those demonstrated include ethanol, acetone, butanol, various lipids, lactic acid, hydrogen, and methane. Several potential native products of the plant, in addition to cellulose for paper production, are also identified: waxes, proteins, and allelopathic compounds, such as sorgoleone. DA - 2012/5// PY - 2012/5// DO - 10.1016/j.indcrop.2011.12.011 VL - 37 IS - 1 SP - 362-375 SN - 1872-633X KW - Sorghum bicolor (L.) Moench KW - Sweet sorghum KW - Fermentation KW - Lignocellulosic bagasse KW - Biofuel KW - Natural products ER - TY - JOUR TI - Improving bioretention/biofiltration performance with restorative maintenance AU - Brown, Robert A. AU - Hunt, William F. T2 - WATER SCIENCE AND TECHNOLOGY AB - One of the most popular Stormwater Control Measures is bioretention, or biofiltration. Anecdotal evidence suggests that well-designed bioretention cells are often not adequately installed and that maintenance is lacking, leading to less-than-adequate water storage volume and/or surface infiltration rates post-construction. In March 2009, two sets of bioretention cells were repaired by excavating the top 75 mm of fill media, increasing the bioretention surface storage volume by nearly 90% and the infiltration rate by up to a factor of 10. Overflow volume decreased from 35 and 37% in the pre-repair state for two different sets of cells, respectively, to 11 and 12%. Nearly all effluent pollutant loads exiting the post-repair cells were lower than their pre-repair conditions. The bioretention systems employed two different media depths (0.6 and 0.9 m). The deeper media cells discharged less outflow volume than the shallower cells, with 10-11% more runoff volume leaving as exfiltration from the 0.9-m than from the 0.6-m media depth cells. This study showed that maintenance is both critical and beneficial to restore otherwise poorly performing bioretention. Moreover, while deeper media cells did outperform the shallower systems, the improvement in this case was somewhat modest vis-à-vis additional construction costs. DA - 2012/// PY - 2012/// DO - 10.2166/wst.2012.860 VL - 65 IS - 2 SP - 361-367 SN - 1996-9732 KW - bioretention KW - construction KW - LID KW - maintenance KW - media depth KW - runoff KW - stormwater KW - SUDS KW - WSUD ER - TY - JOUR TI - Evaluation of Simulated Strategies for Reducing Nitrate-Nitrogen Losses through Subsurface Drainage Systems AU - Ale, Srinivasulu AU - Bowling, Laura C. AU - Youssef, Mohamed A. AU - Brouder, Sylvie M. T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - The nitrates (NO3–N) lost through subsurface drainage in the Midwest often exceed concentrations that cause deleterious effects on the receiving streams and lead to hypoxic conditions in the northern Gulf of Mexico. The use of drainage and water quality models along with observed data analysis may provide new insight into the water and nutrient balance in drained agricultural lands and enable evaluation of appropriate measures for reducing NO3–N losses. DRAINMOD-NII, a carbon (C) and nitrogen (N) simulation model, was field tested for the high organic matter Drummer soil in Indiana and used to predict the effects of fertilizer application rate and drainage water management (DWM) on NO3–N losses through subsurface drainage. The model was calibrated and validated for continuous corn (Zea mays L.) (CC) and corn–soybean [Glycine max (L.) Merr.] (CS) rotation treatments separately using 7 yr of drain flow and NO3–N concentration data. Among the treatments, the Nash-Sutcliffe efficiency of the monthly NO3–N loss predictions ranged from 0.30 to 0.86, and the percent error varied from −19 to 9%. The medians of the observed and predicted monthly NO3–N losses were not significantly different. When the fertilizer application rate was reduced ∼20%, the predicted NO3–N losses in drain flow from the CC treatments was reduced 17% (95% confidence interval [CI], 11–25), while losses from the CS treatment were reduced by 10% (95% CI, 1–15). With DWM, the predicted average annual drain flow was reduced by about 56% (95% CI, 49–67), while the average annual NO3–N losses through drain flow were reduced by about 46% (95% CI, 32–57) for both tested crop rotations. However, the simulated NO3–N losses in surface runoff increased by about 3 to 4 kg ha−1 with DWM. For the simulated conditions at the study site, implementing DWM along with reduced fertilizer application rates would be the best strategy to achieve the highest NO3–N loss reductions to surface water. The suggested best strategies would reduce the NO3–N losses to surface water by 38% (95% CI, 29–46) for the CC treatments and by 32% (95% CI, 23–40) for the CS treatments. DA - 2012/1// PY - 2012/1// DO - 10.2134/jeq2010.0466 VL - 41 IS - 1 SP - 217-228 SN - 0047-2425 ER - TY - JOUR TI - Developments in mycotoxin analysis: an update for 2010-2011 AU - Shephard, G. S. AU - Berthiller, E. AU - Burdaspal, P. A. AU - Crews, C. AU - Jonker, M. A. AU - Krska, R. AU - MacDonald, S. AU - Malone, R. J. AU - Maragos, C. AU - Sabino, M. AU - Solfrizzo, M. AU - Van Egmond, H. P. AU - Whitaker, T. B. T2 - WORLD MYCOTOXIN JOURNAL AB - This review highlights developments in mycotoxin analysis and sampling over a period between mid-2010 and mid-2011. It covers the major mycotoxins: aflatoxins, Alternaria toxins, ergot alkaloids, fumonisins, ochratoxin, patulin, trichothecenes, and zearalenone. Analytical methods for mycotoxins continue to be developed and published. Despite much interest in immunochemical methods and in the rapid development of LC-MS methodology, more conventional methods, sometimes linked to novel clean-up protocols, have also been the subject of research publications over the above period. Occurrence of mycotoxins falls outside the main focus of this review; however, where relevant to analytical method development, this has been mentioned. DA - 2012/2// PY - 2012/2// DO - 10.3920/wmj2011.1338 VL - 5 IS - 1 SP - 3-30 SN - 1875-0796 KW - aflatoxin KW - Alternaria KW - ergot KW - fumonisin KW - ochratoxin KW - patulin KW - trichothecene KW - zearalenone KW - sampling ER - TY - JOUR TI - Analysis of quantitative disease resistance to southern leaf blight and of multiple disease resistance in maize, using near-isogenic lines AU - Belcher, Araby R. AU - Zwonitzer, John C. AU - Cruz, Jose Santa AU - Krakowsky, Mathew D. AU - Chung, Chia-Lin AU - Nelson, Rebecca AU - Arellano, Consuelo AU - Balint-Kurti, Peter J. T2 - THEORETICAL AND APPLIED GENETICS DA - 2012/2// PY - 2012/2// DO - 10.1007/s00122-011-1718-1 VL - 124 IS - 3 SP - 433-445 SN - 1432-2242 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84860880839&partnerID=MN8TOARS ER - TY - JOUR TI - Modeling water, carbon, and nitrogen dynamics for two drained pine plantations under intensive management practices AU - Tian, Shiying AU - Youssef, Mohamed A. AU - Skaggs, R. Wayne AU - Amatya, Devendra M. AU - Chescheir, George M. T2 - FOREST ECOLOGY AND MANAGEMENT AB - This paper reports results of a study to test the reliability of the DRAINMOD-FOREST model for predicting water, soil carbon (C) and nitrogen (N) dynamics in intensively managed forests. The study site, two adjacent loblolly pine (Pinus taeda L.) plantations (referred as D2 and D3), are located in the coastal plain of North Carolina, USA. Controlled drainage (with weir and orifice) and various silvicultural practices, including nitrogen (N) fertilizer application, thinning, harvesting, bedding, and replanting, were conducted on the study site. Continuous collection of hydrological and water quality data (1988–2008) were used for model evaluation. Comparison between predicted and measured hydrologic variables showed that the model accurately predicted long-term subsurface drainage dynamics and water table fluctuations in both loblolly pine plantations. Predicted mean and standard deviation of annual drainage matched measured values very well: 431 ± 217 vs. 436 ± 231 mm for D2 site and 384 ± 152 vs. 386 ± 160 mm for D3 site. Nash–Sutcliffe coefficients (NSE) were above 0.9 for drainage predictions on annual and monthly basis and above 0.86 for predictions of daily water table fluctuations. Compared to measurements in other similar studies, the model also reasonably estimated long-term dynamics of organic matter pools on forest floor and in forest soil. Predicted mean and standard deviation of annual nitrate exports were comparable to measured values: 1.6 ± 1.3 vs. 1.5 ± 1.5 kg ha−1 for D2 site, and 1.4 ± 1.3 vs. 1.3 ± 1.1 kg ha−1 for D3 site, respectively. Predicted nitrate export dynamics were also in excellent agreement with field measurements as indicated by NSE above 0.90 and 0.84 on annual and monthly bases, respectively. The model, thus successfully tested, was applied to predicted hydrological and biogeochemical responses to drainage water management and silvicultural practices. Specifically, the model predicted reduced rainfall interception and ET after clear cutting, both of which led to increased water yield and elevated water table, as expected. The model also captured temporary changes in nitrogen transformations following forest harvesting, including increased mineralization, nitrification, denitrification, and decreased plant uptake. Overall, this study demonstrated that DRAINMOD-FOREST can predict water, C and N dynamics in drained pine forests under intensive management practices. DA - 2012/1/15/ PY - 2012/1/15/ DO - 10.1016/j.foreco.2011.09.041 VL - 264 SP - 20-36 SN - 1872-7042 KW - Forest hydrology KW - C and N dynamics KW - Silvicultural practices KW - Forest ecosystem modeling KW - DRAINMOD-FOREST ER -