TY - JOUR TI - One-dimensional modeling of suspended sediment dynamics in dam reservoirs AU - Guertault, Lucie AU - Camenen, Benoit AU - Peteuil, Christophe AU - Paquier, André AU - Faure, Jean Baptiste T2 - Journal of Hydraulic Engineering AB - Continuous sedimentation of fine sediments in dam reservoirs triggers considerable economic and ecological impacts worldwide. The definition of appropriate reservoir management procedures requires accurate tools for predicting the sediment dynamics both in the reservoir and downstream reaches. In this article, a one-dimensional numerical model aiming to reproduce suspended sediment dynamics is presented. To take into account water intake locations and vertical distribution of suspended sediments in areas of larger water depths close to dams, an additional module is developed. The model is applied to a reach of the French Upper Rhône River, including two reservoirs. The calibrated model provides accurate flux estimates and reproduces erosion and deposition patterns observed in the reservoir for several scenarios. The additional module allows to improve the estimation of the sand load released by low-level outlets. Eventually, the model could be used either to provide insights on the outcome of past flushing operations or as a predictive tool to prepare future operations. DA - 2016/// PY - 2016/// DO - 10.1061/(ASCE)HY.1943-7900.0001157 VL - 142 IS - 10 SP - 04016033 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84988591480&partnerID=MN8TOARS ER - TY - JOUR TI - Selective Oxidation of Lignin into Aromatic Aldehydes Using Niobium Oxalate T2 - Transactions of the ASABE AB - Abstract. There is a strong interest in using lignin as a precursor for synthesis of value-added chemicals such as aromatic aldehydes. Among the existing processes for converting lignin into aromatic aldehydes, catalytic oxidation appears to be most promising. In this research, we explored niobium oxalate as a selective oxidation catalyst and hydrogen peroxide as an oxidant for oxidizing lignin into vanillin and syringaldehyde. Research objectives were to (1) determine the effect of catalyst mass, lignin concentration, and H2O2 concentration on synthesis of aromatic aldehydes; (2) study the effect of reaction temperature; and (3) optimize the reaction parameters. Batch experiments were performed via central composite design at 95°C using 4 to 12 g of lignin per 100 mL, 3 to 7 mL of H2O2 per 100 mL, and 0.5 to 1.0 g of catalyst per 100 mL. Results indicated that under optimum conditions (3 mL of H2O2, 0.5 g of catalyst, and 7.26 g of lignin), 65.58 mg g-1 of vanillin and 23.12 mg g-1 of syringaldehyde were produced. In addition, production of aldehydes showed dependency on temperature in the range of 85°C to 100°C, with 100°C producing the highest product concentrations. It is theorized that perhydroxyl anion (HOO-), being a strong nucleophile and the most active agent in alkaline hydrogen peroxide, breaks the α and β-aryl ether bonds of lignin to produce corresponding aldehydes. It is suggested that niobium is a potential catalyst for selective oxidation of lignin. DA - 2016/4/21/ PY - 2016/4/21/ DO - 10.13031/trans.59.10908 VL - 59 IS - 2 SP - 727-735 J2 - Trans. ASABE OP - SN - 2151-0032 2151-0040 UR - http://dx.doi.org/10.13031/trans.59.10908 DB - Crossref ER - TY - JOUR TI - World geography and power, national capitals, and inequality as cross-national causes of food security and environmental outcomes AU - Kick, Edward AU - Balcazar Tellez, Maria AU - Thompson, Gretchen AU - Classen, John T2 - AIMS Agriculture and Food AB - Treatments of sustainability outcomes such as food security, economic development and environmental degradation typically have adopted monocausal approaches. Many have argued for substantial increases in world meat production as the panacea to global food insecurity. We use global and national synthetic explanations and path analytic approaches to examine sustainability outcomes for 200 nations. Both strong direct or indirect links are found among global geography, global power and national capitals, as well as warfare and military expenditures, and economic development. These factors are differentially predictive of the other key measures of sustainability. DA - 2016/// PY - 2016/// DO - 10.3934/agrfood.2016.4.419 VL - 1 IS - 4 SP - 419-438 LA - en OP - SN - 2471-2086 UR - http://dx.doi.org/10.3934/agrfood.2016.4.419 DB - Crossref ER - TY - SOUND TI - Coordinated Efforts for FSMA Preparedness in North Carolina AU - Simmons, O.D., III AU - MacMullan, A. AU - McReynolds, R. DA - 2016/5/19/ PY - 2016/5/19/ ER - TY - CONF TI - Reinforcing Key Learning Concepts of Food Safety & The FSMA Through Customizable Interactive Practices AU - Ducharme, D.T. AU - Gunter, C. AU - Simmons, O.D., III AU - Rogers, E.T. AU - Johnston, L. AU - Nobles, C. T2 - North Carolina Cooperative Extension Annual Conference C2 - 2016/11/15/ CY - Raleigh, NC DA - 2016/11/15/ PY - 2016/11/15/ ER - TY - CONF TI - What Does the Reality of the Food Safety Modernization Act (FSMA) Look Like for our Stakeholders? AU - Simmons, O.D., III AU - Gunter, C. AU - Ducharme, D.T. AU - Rogers, E.T. AU - Nobles, C. AU - Johnston, L. T2 - North Carolina Cooperative Extension Annual Conference C2 - 2016/11/15/ CY - Raleigh, NC DA - 2016/11/15/ PY - 2016/11/15/ ER - TY - CONF TI - Knowledge and Risk Communication for Undercooked Oyster Preparation in Restaurants AU - Arnold, N. AU - Cope, S. AU - Simmons, O.D., III AU - Chapman, B. T2 - International Association for Food Protection Annual Meeting C2 - 2016/8/1/ CY - St. Louis, MO. DA - 2016/8/1/ PY - 2016/8/1/ ER - TY - JOUR TI - Modeling the Growth of Archaeon Halobacterium halobium Affected by Temperature and Light AU - Lu, Hao AU - Yuan, Wenqiao AU - Cheng, Jay AU - Rose, Robert B. AU - Classen, John J. AU - Simmons, Otto D. T2 - Applied Biochemistry and Biotechnology DA - 2016/10/14/ PY - 2016/10/14/ DO - 10.1007/s12010-016-2270-x VL - 181 IS - 3 SP - 1080-1095 J2 - Appl Biochem Biotechnol LA - en OP - SN - 0273-2289 1559-0291 UR - http://dx.doi.org/10.1007/s12010-016-2270-x DB - Crossref KW - Halobacterium holobium KW - Sigmoidal model KW - Temperature effect KW - Light intensity effect KW - Bacteriorhodopsin ER - TY - RPRT TI - After the flood: Inspect, purge, and disinfect your well. North Carolina Cooperative Extension – Disaster Recovery AU - Burchell, M.R. AU - Rashash, D. DA - 2016/// PY - 2016/// M3 - NC State Extension Publications UR - https://content.ces.ncsu.edu/after-the-flood-inspect-purge-and-disinfect-your-well ER - TY - RPRT TI - Evaluation of Current and Potential Use to Improve Water Quality Trends and Protect Human Health. VT/NC State Regional Collaborative Proposal Planning and Development Grants AU - Burchell, M.R. AU - Thompson, T.W. AU - Broome, S.W. AU - Krometis, L.A. AU - Badgley, B. A3 - N.C. State University College of Agriculture and Life Sciences DA - 2016/9// PY - 2016/9// M3 - Final Report PB - N.C. State University College of Agriculture and Life Sciences ER - TY - JOUR TI - Development and preliminary evaluation of an integrated field scale model for perennial bioenergy grass ecosystems in lowland areas AU - Tian, S. AU - Youssef, M.A. AU - Chescheir, G.M. AU - Skaggs, R.W. AU - Cacho, J. AU - Nettles, J. T2 - Environmental Modelling & Software AB - Computer models are useful tools for evaluating environmental and economic sustainability of proposed dedicated cellulosic grass ecosystems for biofuel production. This study developed an integrated, field scale, and process-based ecosystem model (DRAINMOD-GRASS) for simulating hydrological processes, soil carbon and nitrogen cycling, and plant growth in cropping systems for producing bioenergy grasses in lowland areas. We tested the model using measurements from three replicated switchgrass (Panicum virgatum) plots located in eastern North Carolina, USA. Results showed that the model accurately predicted 5-year (2009–2013) biomass yield. Predicted daily water table depth closely matched field measurements with Nash-Sutcliffe coefficient of 0.86. The model also accurately predicted temporal dynamics of daily soil moisture and temperature with Nash-Sutcliffe coefficients of 0.7 and 0.9, respectively. Predicted seasonal changes in net N mineralization and nitrification rates were comparable to field measurements in 2011 and 2012. DA - 2016/10// PY - 2016/10// DO - 10.1016/J.ENVSOFT.2016.06.029 VL - 84 SP - 226-239 J2 - Environmental Modelling & Software LA - en OP - SN - 1364-8152 UR - http://dx.doi.org/10.1016/J.ENVSOFT.2016.06.029 DB - Crossref KW - DRAINMOD-GRASS KW - Hydrology KW - Biogeochemistry KW - Grass growth KW - Switchgrass ER - TY - CONF TI - Dynamic vs. quasi-steady modeling of morphodynamic processes: A physics-based selection criterion C2 - 2016/// C3 - River Flow 2016 DA - 2016/// UR - https://www.crcpress.com/River-Flow-2016-Iowa-City-USA-July-11-14-2016/Constantinescu-Garcia-Hanes/p/book/9781138029132 ER - TY - JOUR TI - Effects of Riparian Buffer Vegetation and Width: A 12-Year Longitudinal Study AU - King, S. E. AU - Osmond, D. L. AU - Smith, J. AU - Burchell, M. R. AU - Dukes, M. AU - Evans, R. O. AU - Knies, S. AU - Kunickis, S. T2 - Journal of Environmental Quality AB - Agricultural contributions of nitrogen are a serious concern for many water resources and have spurred the implementation of riparian buffer zones to reduce groundwater nitrate (NO). The optimum design for buffers is subject to debate, and there are few long-term studies. The objective of this project was to determine the effectiveness over time (12 yr) of buffer types (trees, switchgrass, fescue, native, and a control) and buffer widths (8 and 15 m) by measuring groundwater NO-N and dissolved organic carbon (DOC) trends. At the intermediate groundwater depth (1.5-2.1 m), NO-N reduction effectiveness was 2.5 times greater (46 vs. 16%) for the wider buffer, and, regardless of width, buffer effectiveness increased 0.62% yr. Buffer vegetative type was never statistically significant. In the deep-groundwater depth (2.1-3.5 m), there was no change in NO-N removal over time, although the statistical interaction of width and vegetative type indicated a wide range of removal rates (19-82%). The DOC concentrations were analyzed at the field/buffer and buffer/stream sampling locations. Depending on location position and groundwater sampling depth, DOC concentrations ranged from 1.6 to 2.8 mg L at Year 0 and increased at a rate of 0.13 to 0.18 mg L yr but always remained low (≤5.0 mg L). Greater DOC concentrations in the intermediate-depth groundwater did not increase NO-N removal; redox measurements indicated intermittent reduced soil conditions may have been limiting. This study suggests that riparian buffer width, not vegetation, is more important for NO-N removal in the middle coastal plain of North Carolina for a newly established buffer. DA - 2016/7// PY - 2016/7// DO - 10.2134/jeq2015.06.0321 VL - 45 IS - 4 SP - 1243-1251 J2 - J. Environ. Qual. LA - en OP - SN - 0047-2425 UR - http://dx.doi.org/10.2134/jeq2015.06.0321 DB - Crossref ER - TY - JOUR TI - Nutrients in the nexus AU - Davidson, Eric A. AU - Nifong, Rachel L. AU - Ferguson, Richard B. AU - Palm, Cheryl AU - Osmond, Deanna L. AU - Baron, Jill S. T2 - Journal of Environmental Studies and Sciences AB - Synthetic nitrogen (N) fertilizer has enabled modern agriculture to greatly improve human nutrition during the twentieth century, but it has also created unintended human health and environmental pollution challenges for the twenty-first century. Averaged globally, about half of the fertilizer-N applied to farms is removed with the crops, while the other half remains in the soil or is lost from farmers’ fields, resulting in water and air pollution. As human population continues to grow and food security improves in the developing world, the dual development goals of producing more nutritious food with low pollution will require both technological and socio-economic innovations in agriculture. Two case studies presented here, one in sub-Saharan Africa and the other in Midwestern United States, demonstrate how management of nutrients, water, and energy is inextricably linked in both small-scale and large-scale food production, and that science-based solutions to improve the efficiency of nutrient use can optimize food production while minimizing pollution. To achieve the needed large increases in nutrient use efficiency, however, technological developments must be accompanied by policies that recognize the complex economic and social factors affecting farmer decision-making and national policy priorities. Farmers need access to affordable nutrient supplies and support information, and the costs of improving efficiencies and avoiding pollution may need to be shared by society through innovative policies. Success will require interdisciplinary partnerships across public and private sectors, including farmers, private sector crop advisors, commodity supply chains, government agencies, university research and extension, and consumers. DA - 2016/2/15/ PY - 2016/2/15/ DO - 10.1007/S13412-016-0364-Y VL - 6 IS - 1 SP - 25-38 J2 - J Environ Stud Sci LA - en OP - SN - 2190-6483 2190-6491 UR - http://dx.doi.org/10.1007/S13412-016-0364-Y DB - Crossref ER - TY - JOUR TI - Increased Temperatures Combined with Lowered Salinities Differentially Impact Oyster Size Class Growth and Mortality AU - Rybovich, M. AU - La Peyre, M.K. AU - Hall, S.G. AU - La Peyre, J.F. T2 - Journal of Shellfish Research AB - Changes in the timing and interaction of seasonal high temperatures and low salinities as predicted by climate change models could dramatically alter oyster population dynamics. Little is known explicitly about how low salinity and high temperature combinations affect spat (<25mm), seed (25–75mm), andmarket (>75mm) oyster growth and mortality. Using field and laboratory studies, this project quantified the combined effects of extremely low salinities (<5) and high temperatures (>30°C) on growth and survival of spat, seed, andmarket-sized oysters. In 2012 and 2013, hatchery-produced oysters were placed in open and closed cages at three sites in Breton Sound, LA, along a salinity gradient that typically ranged from 5 to 20. Growth and mortality were recorded monthly. Regardless of size class, oysters at the lowest salinity site (annualmean = 4.8) experienced significantly highermortality and lower growth than oysters located in higher salinity sites (annual means = 11.1 and 13.0, respectively); furthermore, all oysters in open cages at the two higher salinity sites experienced higher mortality than in closed cages, likely due to predation. To explicitly examine oyster responses to extreme low salinity and high temperature combinations, a series of laboratory studies were conducted. Oysters were placed in 18 tanks in a fully crossed temperature (25°C, 32°C) by salinity (1, 5, and 15) study with three replicates, and repeated at least twice for each oyster size class. Regardless of temperature, seed and market oysters held in low salinity tanks (salinity 1) experienced 100% mortality within 7 days. In contrast, at salinity 5, temperature significantly affected mortality; oysters in all size classes experienced greater than 50%mortality at 32°C and less than 40%mortality at 25°C. At the highest salinity tested (15), only market-sized oysters held at 32°C experienced significant mortality (>60%). These studies demonstrate that high water temperatures (>30°C) and low salinities (<5) negatively impact oyster growth and survival differentially and that high temperatures alone may negatively impact market-sized oysters. It is critical to understand the potential impacts of climate and anthropogenic changes on oyster resources to better adapt and manage for long-term sustainability. DA - 2016/// PY - 2016/// DO - 10.2983/035.035.0112 VL - 35 IS - 1 SP - 101-113 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84971010752&partnerID=MN8TOARS KW - Crassostrea virginica KW - eastern oyster KW - northern Gulf of Mexico KW - estuary KW - climate change ER - TY - JOUR TI - Evaluating a process-based model for use in streambank stabilization: insights on the Bank Stability and Toe Erosion Model (BSTEM) AU - Klavon, Kate AU - Fox, Garey AU - Guertault, Lucie AU - Langendoen, Eddy AU - Enlow, Holly AU - Miller, Ron AU - Khanal, Anish T2 - Earth Surface Processes and Landforms AB - Abstract Streambank retreat is a complex cyclical process involving subaerial processes, fluvial erosion, seepage erosion, and geotechnical failures and is driven by several soil properties that themselves are temporally and spatially variable. Therefore, it can be extremely challenging to predict and model the erosion and consequent retreat of streambanks. However, modeling streambank retreat has many important applications, including the design and assessment of mitigation strategies for stream revitalization and stabilization. In order to highlight the current complexities of modeling streambank retreat and to suggest future research areas, this paper reviewed one of the most comprehensive streambank retreat models available, the Bank Stability and Toe Erosion Model (BSTEM), which has recently been integrated with several popular hydrodynamic and sediment transport models including the Hydrologic Engineering Center's River Analysis System (HEC‐RAS). The objectives of this paper were to: (i) comprehensively review studies that have utilized BSTEM and report their findings, (ii) address the limitations of the model so that it can be applied appropriately in its current form, and (iii) suggest directions of research that will help make the model a more useful tool in future applications. The paper includes an extensive overview of peer reviewed studies to guide future users of BSTEM. The review demonstrated that the model needs further testing and evaluation outside of the central United States. Also, further development is needed in terms of accounting for spatial and temporal variability in geotechnical and fluvial erodibility parameters, incorporating subaerial processes, and accounting for the influence of riparian vegetation on streambank pore‐water pressure dynamics, applied shear stress, and erodibility parameters. Copyright © 2016 John Wiley & Sons, Ltd. DA - 2016/12/15/ PY - 2016/12/15/ DO - 10.1002/ESP.4073 VL - 42 IS - 1 SP - 191-213 J2 - Earth Surf. Process. Landforms LA - en OP - SN - 0197-9337 UR - http://dx.doi.org/10.1002/ESP.4073 DB - Crossref KW - Bank Stability and Toe Erosion Model KW - borehole shear test KW - fluvial erosion KW - geotechnical parameters KW - jet erosion test KW - modeling KW - streambank retreat ER - TY - JOUR TI - Biomass supply chain management in North Carolina (part 1): predictive model for cropland conversion to biomass feedstocks AU - R Caffrey, Kevin AU - S Chinn, Mari AU - W Veal, Matthew T2 - AIMS Energy AB - Increased interest in biomass cultivation requires detailed analysis of spatial production potential of possible biorefinery locations, with emphasis on feedstock production cost minimization. Integrated assessment of publicly available spatial data on current crop production, soil type, and yield potential, coupled with techno-economic production cost estimates, can support a functional method for rapid analysis of potential biorefinery sites. A novel predictive model was developed to determine cropland conversion using a probabilistic profit based equation for multiple biomass crops: giant reed, miscanthus, switchgrass, and sorghum (with either canola or barley as a winter crop). The three primary regions of North Carolina (Mountains, Piedmont, and Coastal Plain) were used as a case study and with a single parameter uncertainty analysis was completed. According to the model, the county chosen to represent the Coastal Plain (Duplin County) had the largest potential acreage that would be converted (15,071 ha, 7.1% total land, 9.3% of cropland) primarily to sorghum with canola as a winter crop. Large portions were also predicted to convert to giant reed and switchgrass, depending on the price and yield parameters used. The Piedmont (Granville County, 7697 ha, 5.5% total land, 6.9% cropland) and Mountain (Henderson County, 2117 ha, 2.2% total land, 2.3% cropland) regions were predicted to convert primarily to switchgrass acreage for biomass production, with much less available biomass overall compared to the Coastal Plain. This model provided meaningful insight into regional cropping systems and feedstock availability, allowing for improved business planning in designated regions. Determination of cropland conversion is imperative to develop realistic biomass logistical operations, which in conjunction can assist with rapid determination of profitable biomass availability. After this rapid analysis method is conducted in-depth on-ground biorefinery feasibility analysis can occur, ensuring resource are used only in locations with a high potential for available low cost biomass feedstocks. DA - 2016/// PY - 2016/// DO - 10.3934/energy.2016.2.256 VL - 4 IS - 2 SP - 256-279 LA - en OP - SN - 2333-8334 UR - http://dx.doi.org/10.3934/energy.2016.2.256 DB - Crossref KW - Biomass KW - techno-economic KW - feedstock modeling KW - bioenergy KW - spatial analysis KW - yield determination KW - giant reed KW - switchgrass KW - sorghum KW - miscanthus ER - TY - JOUR TI - Biomass supply chain management in North Carolina (part 2): biomass feedstock logistical optimization AU - Caffrey, Kevin AU - Chinn, Mari AU - Veal, Matthew AU - Kay, Michael T2 - AIMS Energy AB - Biomass logistics operations account for a major portion of the feedstock cost of running a biorefinery, and make up a significant portion of total system operational costs. Biomass is a bulky perishable commodity that is required in large quantities year round for optimal biorefinery operations. As a proof of concept for a decision making tool for biomass production and delivery, a heuristic was developed to determine biorefinery location, considering city size, agricultural density, and regional demographics. Switchgrass and sorghum (with winter canola) were selected to examine as viable biomass feedstocks based on positive economic results determined using a predictive model for cropland conversion potential. Biomass harvest systems were evaluated to examine interrelationships of biomass logistical networks and the least cost production system, with results demonstrating a need to shift to maximize supply-driven production harvest operations and limit storage requirements. For this supply-driven production harvest operations approach a harvest window from September until March was selected for producing big square bales of switchgrass for storage until use, forage chopped sorghum from September to December, and forage chopped switchgrass from December to March. A case study of the three major regions of North Carolina (Mountains, Piedmont, and Coastal Plain) was used to assess logistical optimization of the proposed supply-driven production harvest system. Potential biomass production fields were determined within a hundred mile radius of the proposed biorefinery location, with individual fields designated for crop and harvest system by lowest transportation cost. From these selected fields, crops and harvest system regional storage locations were determined using an alternate location-allocation heuristic with set storage capacity per site. Model results showed that the supply-driven production harvest system greatly reduced system complexity, maximized annual usage of high cost specialized equipment, and reduced logistical operations cost. The siting method and developed model shows promise and can be used for computational analysis of potential biorefinery site biomass production systems before costly on the ground logistical analysis. DA - 2016/// PY - 2016/// DO - 10.3934/energy.2016.2.280 VL - 4 IS - 2 SP - 280-299 LA - en OP - SN - 2333-8334 UR - http://dx.doi.org/10.3934/energy.2016.2.280 DB - Crossref KW - Biomass logistics KW - switchgrass KW - sorghum KW - biomass harvest system KW - storage analysis ER - TY - JOUR TI - Characterization of Clostridium ljungdahlii OTA1: a non-autotrophic hyper ethanol-producing strain AU - Whitham, Jason M. AU - Schulte, Mark J. AU - Bobay, Benjamin G. AU - Bruno-Barcena, Jose M. AU - Chinn, Mari S. AU - Flickinger, Michael C. AU - Pawlak, Joel J. AU - Grunden, Amy M. T2 - Applied Microbiology and Biotechnology DA - 2016/11/19/ PY - 2016/11/19/ DO - 10.1007/S00253-016-7978-6 VL - 101 IS - 4 SP - 1615-1630 J2 - Appl Microbiol Biotechnol LA - en OP - SN - 0175-7598 1432-0614 UR - http://dx.doi.org/10.1007/S00253-016-7978-6 DB - Crossref KW - Acetyl-coA KW - Carbon monoxide dehydrogenase KW - Clostridium ljungdahlii KW - Ethanol KW - Wood-Ljungdahl pathway ER - TY - JOUR TI - Variability of Erodibility Parameters from Laboratory Mini Jet Erosion Tests AU - Khanal, A. AU - Fox, G. A. AU - Al-Madhhachi, A. T. T2 - Journal of Hydrologic Engineering AB - Application of jet erosion tests (JETs) to study in situ erodibility is gaining popularity. New versions of the JET (original JET versus mini-JET) and new data analysis techniques have introduced questions regarding their operation and data collection procedures. One of the major issues regarding JETs is the high degree of variability of the erodibility parameters (i.e., erodibility coefficient, kd, and critical shear stress, τc). This variability has been attributed to heterogeneity in different soil properties under natural field conditions, but limited research has quantified variability under controlled laboratory conditions, especially for the newer mini-JET. This study uniquely conducted 20 mini-JETs under controlled laboratory conditions on each of two soil types of contrasting texture. Mini-JETs were conducted in situ on streambanks of these same soils in previous research. The laboratory mini-JETs predicted similar values of most parameters with much less variability than in the field. Three to five mini-JETs conducted in the laboratory estimated erodibility parameters with a precision of 25% at a 95% confidence level. Laboratory JETs on disturbed, remolded samples provided baseline estimates of in situ erodibility parameters. Additional mini-JETs were conducted at three different head settings on the two soil types. The influence of the head setting was dependent on the soil type, solution technique, and detachment model. In general, variability in derived erodibility parameters increased at larger head settings especially for the less-erodible soil. Existing mini-JET data were resampled to evaluate the effect of the initial time interval and termination time interval of data collection on derived erodibility parameters. Both initial and termination time intervals were most influential at larger head settings. When the applied pressure head is sufficient to create scouring upon test initiation, an initial time interval of at least 30 s and a termination time interval of at least 300 s is recommended for less-erodible soils. DA - 2016/10// PY - 2016/10// DO - 10.1061/(ASCE)HE.1943-5584.0001404 VL - 21 IS - 10 SP - 04016030 J2 - J. Hydrol. Eng. LA - en OP - SN - 1084-0699 1943-5584 UR - http://dx.doi.org/10.1061/(ASCE)HE.1943-5584.0001404 DB - Crossref KW - Erodibility KW - Jet erosion test KW - Mini-JET KW - Sediment detachment KW - Variability ER - TY - CONF TI - Thermal regimes and fish assemblages in a restored Oklahoma stream AU - Woytowitz, E.L. AU - Brewer, S.K. AU - Fox, G.A. AB - Abstract. Stream restoration aims to re-establish the structure, function, and diversity of streams that have been altered from their natural state. Effective restoration approaches address both physical and ecological aspects of stream environments. To assess the physical and ecological condition of a restored Oklahoma stream, this study investigated spatial and temporal variation in water temperatures around in-stream structures, along vertical profiles, and in shaded versus nonshaded reaches using automated temperature loggers. Also, fish species richness and diversity (Shannon-Weiner diversity index (H‘)) were quantified at nonshaded and shaded locations by sampling in the morning and afternoon using a seine. All research was conducted within undisturbed and restored reaches of Cow Creek, a third-order stream in Stillwater, OK. Mann-Whitney U tests, Kruskal-Wallis one-way analysis of variance (ANOVA) by ranks tests, and Pearson product-moment correlation coefficient (r) calculations were performed on the fish diversity measures. Results revealed that maximum daily water temperature was generally warmer downstream of in-stream structures and that fish species richness and H‘ were significantly different at different times of day but these differences were not related to riparian shading. This suggests that in-stream structures affect thermal regimes and that water temperature, more so than light, plays an important role in shaping fish distributions. In the future, stream restoration projects would benefit from considering the influence of in-stream structures on water temperature and water temperature on aquatic organisms. C2 - 2016/// C3 - 2016 American Society of Agricultural and Biological Engineers Annual International Meeting, ASABE 2016 DA - 2016/// DO - 10.13031/aim.20162377956 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85009101198&partnerID=MN8TOARS ER - TY - JOUR TI - Streambanks: A net source of sediment and phosphorus to streams and rivers AU - Fox, Garey A. AU - Purvis, Rebecca A. AU - Penn, Chad J. T2 - Journal of Environmental Management AB - Sediment and phosphorus (P) are two primary pollutants of surface waters. Many studies have investigated loadings from upland sources or even streambed sediment, but in many cases, limited to no data exist to determine sediment and P loading from streambanks on a watershed scale. The objectives of this paper are to review the current knowledge base on streambank erosion and failure mechanisms, streambank P concentrations, and streambanks as P loading sources and then also to identify future research needs on this topic. In many watersheds, long-term loading of soil and associated P to stream systems has created a source of eroded soil and P that may interact with streambank sediment and be deposited in floodplains downstream. In many cases streambanks were formed from previously eroded and deposited alluvial material and so the resulting soils possess unique physical and chemical properties from adjacent upland soils. Streambank sediment and P loading rates depend explicitly on the rate of streambank migration and the concentration of P stored within bank materials. From the survey of literature, previous studies report streambank total P concentrations that consistently exceeded 250 mg kg(-1) soil. Only a few studies also reported water soluble or extractable P concentrations. More research should be devoted to understanding the dynamic processes between different P pools (total P versus bioavailable P), and sorption or desorption processes under varying hydraulic and stream chemistry conditions. Furthermore, the literature reported that streambank erosion and failure and gully erosion were reported to account for 7-92% of the suspended sediment load within a channel and 6-93% of total P. However, significant uncertainty can occur in such estimates due to reach-scale variability in streambank migration rates and future estimates should consider the use of uncertainty analysis approaches. Research is also needed on the transport rates of dissolved and sediment-bound P through the entire stream system of a watershed to identify critical upland and/or near-stream conservation practices. Extensive monitoring of the impact of restoration/rehabilitation efforts on reducing sediment and P loading are limited. From an application standpoint, streambank P contributions to streams should be more explicitly accounted for in developing total maximum daily loads in watersheds. DA - 2016/10// PY - 2016/10// DO - 10.1016/j.jenvman.2016.06.071 VL - 181 SP - 602-614 J2 - Journal of Environmental Management LA - en OP - SN - 0301-4797 UR - http://dx.doi.org/10.1016/J.JENVMAN.2016.06.071 DB - Crossref KW - Legacy phosphorus KW - Phosphorus KW - Sediment KW - Streambank erosion KW - Streams ER - TY - JOUR TI - Soil pipe flow tracer experiments: 2. Application of a streamflow transient storage zone model AU - Zhou, Y. AU - Wilson, G.V. AU - Fox, G.A. AU - Rigby, J.R. AU - Dabney, S.M. T2 - Hydrological Processes AB - Abstract Soil pipes are important subsurface flow pathways in many soil erosion phenomena. However, limited research has been performed on quantifying and characterizing their flow and transport characteristics. The objectives of this research were to determine the applicability of a streamflow model with transient storage in deriving flow and transport characteristics of soil pipes. Tracer data from pulse inputs were collected in four different soil pipes after a fluorescein dye was injected in the upstream end of each soil pipe network in three branches (west, middle, and east) of a main catchment and a back catchment in Goodwin Creek Experimental Watershed in Mississippi. Multiple sampling stations were positioned along each soil pipe network. The transient storage zone model OTIS‐P was executed inversely to estimate transport parameters by soil pipe reach such as the soil pipe cross‐sectional area ( A ), soil storage zone cross‐sectional area ( A s ), and exchange rate between the soil pipe and the soil storage zone ( α s ). Model convergence was achieved, and simulated breakthrough curves of the reaches were in good agreement with actual tracer data for eight of the nine reaches of the three branches of the Main Catchment and five of the seven reaches of the Back Catchment soil pipe. Simulation parameters for the soil pipe networks were similar to the range of values reported for flow and transport characteristics commonly observed in streams. Inversely, estimated soil pipe flow velocities were higher with increased tortuosity, which led to a smaller cross‐sectional areas predicted for the soil pipe flowpaths, while other parameters were not sensitive to tortuosity. In general, application of One‐Dimensional Transport with Inflow and Storage‐P to this unique soil pipe condition suggested larger transient storage ( A s and α s ) compared with most stream systems. This was hypothesized to be because of relatively higher ratio of the wetted perimeter to flow area in the soil pipe, the hydraulic roughness of the soil pipe, potential retention in collapsed portions of the pipe, and interaction with smaller preferential flow systems. Copyright © 2015 John Wiley & Sons, Ltd. DA - 2016/// PY - 2016/// DO - 10.1002/hyp.10712 VL - 30 IS - 8 SP - 1280-1291 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84947718653&partnerID=MN8TOARS KW - solute transport KW - tracer injection KW - preferential flow KW - pipe network KW - breakthrough curve KW - tortuosity ER - TY - JOUR TI - Streambank sediment loading rates at the watershed scale and the benefit of riparian protection AU - Purvis, Rebecca A. AU - Fox, Garey A. T2 - Earth Surface Processes and Landforms AB - Abstract Streambank erosion is a pathway for sediment and nutrient loading to streams, but insufficient data exist on the magnitude of this source. Riparian protection can significantly decrease streambank erosion in some locations, but estimates of actual sediment load reductions are limited. The objective of this research was to quantify watershed‐scale streambank erosion and estimate the benefits of riparian protection. The research focused on Spavinaw Creek within the Eucha‐Spavinaw watershed in eastern Oklahoma , where composite streambanks consist of a small cohesive topsoil layer underlain by non‐cohesive gravel. Fine sediment erosion from 2003 to 2013 was derived using aerial photography and processed in ArcMap to quantify eroded area. ArcMap was also utilized in determining the bank retreat rate at various locations in relation to the riparian vegetation buffer width. Box and whisker plots clearly showed that sites with riparian vegetation had on average three times less bank retreat than unprotected banks, statistically significant based on non‐parametric t ‐tests. The total soil mass eroded from 2003 to 2013 was estimated at 7.27 × 10 7 kg yr. −1 , and the average bank retreat was 2.5 m yr. −1 . Many current erosion models assume that fluvial erosion is the dominant stream erosion process. Bank retreat was positively correlated with stream discharge and/or stream power, but with considerable variability, suggesting that mass wasting plays an important role in streambank erosion within this watershed. Finally, watershed monitoring programs commonly characterize erosion at only a few sites and may scale results to the entire watershed. Selection of random sites and scaling to the watershed scale greatly underestimated the actual erosion and loading rates. Copyright © 2016 John Wiley & Sons, Ltd. DA - 2016/2/19/ PY - 2016/2/19/ DO - 10.1002/esp.3901 VL - 41 IS - 10 SP - 1327-1336 J2 - Earth Surf. Process. Landforms LA - en OP - SN - 0197-9337 UR - http://dx.doi.org/10.1002/ESP.3901 DB - Crossref KW - ArcGIS KW - riparian vegetation KW - sediment loading KW - streambank erosion ER - TY - JOUR TI - Reservoir Sedimentation and Upstream Sediment Sources: Perspectives and Future Research Needs on Streambank and Gully Erosion AU - Fox, G. A. AU - Sheshukov, A. AU - Cruse, R. AU - Kolar, R. L. AU - Guertault, L. AU - Gesch, K. R. AU - Dutnell, R. C. T2 - Environmental Management AB - The future reliance on water supply and flood control reservoirs across the globe will continue to expand, especially under a variable climate. As the inventory of new potential dam sites is shrinking, construction of additional reservoirs is less likely compared to simultaneous flow and sediment management in existing reservoirs. One aspect of this sediment management is related to the control of upstream sediment sources. However, key research questions remain regarding upstream sediment loading rates. Highlighted in this article are research needs relative to measuring and predicting sediment transport rates and loading due to streambank and gully erosion within a watershed. For example, additional instream sediment transport and reservoir sedimentation rate measurements are needed across a range of watershed conditions, reservoir sizes, and geographical locations. More research is needed to understand the intricate linkage between upland practices and instream response. A need still exists to clarify the benefit of restoration or stabilization of a small reach within a channel system or maturing gully on total watershed sediment load. We need to better understand the intricate interactions between hydrological and erosion processes to improve prediction, location, and timing of streambank erosion and failure and gully formation. Also, improved process-based measurement and prediction techniques are needed that balance data requirements regarding cohesive soil erodibility and stability as compared to simpler topographic indices for gullies or stream classification systems. Such techniques will allow the research community to address the benefit of various conservation and/or stabilization practices at targeted locations within watersheds. DA - 2016/2/17/ PY - 2016/2/17/ DO - 10.1007/s00267-016-0671-9 VL - 57 IS - 5 SP - 945-955 J2 - Environmental Management LA - en OP - SN - 0364-152X 1432-1009 UR - http://dx.doi.org/10.1007/S00267-016-0671-9 DB - Crossref KW - Cohesive sediment transport KW - Gully erosion KW - Reservoir sedimentation KW - Streambank erosion ER - TY - JOUR TI - Estimating Streambank Phosphorus Loads at the Watershed Scale with Uncertainty Analysis Approach AU - Purvis, R. A. AU - Fox, G. A. AU - Penn, C. J. AU - Storm, D. E. AU - Parnell, A. T2 - Journal of Hydrologic Engineering AB - Streambank nutrient loading rates are a growing concern within many watersheds. Only a few studies exist on streambank soil chemistry and phosphorus (P) concentrations, spatial distributions in watersheds, and P loading rates with a consideration of the potential uncertainty associated with the estimates. More so, limited studies compare streambank P loading for streams within similar watersheds and with similar land use and management. The objectives of this research included (1) quantifying the magnitude and spatial distribution of soil pH, electrical conductivity (EC), total P concentration, dissolved P concentration, and the degree of P saturation of streambanks in a watershed; (2) quantifying whether water-soluble phosphorus (WSP) and total phosphorus (TP) loads entering the stream from streambanks are significant based on a combined mass balance and uncertainty analysis approach; and (3) contrasting streambank P concentrations and loadings between two similar streams: Spavinaw Creek (SC) versus Barren Fork Creek (BFC) in eastern Oklahoma. Both SC and BFC flow through the Ozark ecoregion, possess similar geomorphology, and are characterized by similar land uses. Following procedures conducted for BFC, streambank sampling occurred at five sites along SC, and samples were processed for pH, EC, WSP, and TP. Unlike BFC, there were no clear longitudinal trends in WSP, TP, pH, and EC; similar to BFC, no consistent vertical trends were observed. Using estimated sediment loading (727×106 kg) from aerial images and Monte Carlo analysis, it was estimated from 2003 to 2013 there was 1.5×103 kg WSP and 1.4×105 kg TP loaded into SC from streambanks in Oklahoma. Average in-stream estimates were an order of magnitude larger for WSP and comparable for TP. Streambank P contributions and erosion rates along one stream cannot be used to accurately predict P loading along other streams even in similar watersheds with similar hydrology, geomorphology, and land use because of watershed-specific variability in streambank erodibility and streambank P concentrations. Due to the uncertainty associated with critical input parameters, the uncertainty in streambank P loads at the watershed scale can be large and therefore uncertainty analysis approaches should be used in future research. DA - 2016/9// PY - 2016/9// DO - 10.1061/(ASCE)HE.1943-5584.0001402 VL - 21 IS - 9 SP - 04016028 J2 - J. Hydrol. Eng. LA - en OP - SN - 1084-0699 1943-5584 UR - http://dx.doi.org/10.1061/(ASCE)HE.1943-5584.0001402 DB - Crossref KW - Degree of phosphorus saturation KW - Riparian vegetation KW - Sediment KW - Streambank erosion KW - Total phosphorus KW - Water-soluble phosphorus ER - TY - JOUR TI - Deriving Erodibility Parameters of a Mechanistic Detachment Model for Gravels AU - Criswell, D.T. AU - Al-Madhhachi, A.T. AU - Fox, G.A. AU - Miller, R.B. T2 - Transactions of the ASABE AB - Abstract. Recent research has proposed the use of a mechanistic detachment model, called the Wilson model, in place of the excess shear stress equation for predicting the detachment of cohesive soils during erosion. However, this mechanistic detachment model was also proposed as being valid for noncohesive soils but with limited evaluation. Such erodibility parameters are often needed in erosion models developed using a single detachment rate approach for both cohesive and noncohesive soils. Therefore, the objectives of this research were to evaluate the applicability of the Wilson model for noncohesive soils and to evaluate a procedure for deriving the erodibility parameters (b0 and b1) from flume experiments. Gravel samples were extracted from composite streambanks on the Barren Fork Creek in eastern Oklahoma. The samples were sieved into particle size classes, and then at least triplicate flume experiments were performed (gravel sizes of 0.45, 0.60, 1.30, and 1.90 cm). Flow rate, water surface elevation, and scour depth were measured to estimate the energy slope, scour rate, and effective shear stress. The Wilson model was fit to the scour depth data to derive b0 and b1 using the generalized reduced gradient method to minimize the error between the predicted and measured scour. Constraints were required within the solver routine to limit potential solutions of b1. Similar to cohesive soils, b0 and b1 had similar relationships to but different magnitudes than the erodibility coefficient (kd) and critical shear stress (τc) for these gravels. Equivalent b1-τc relationships were derived from the flume tests as compared to the theoretical b1-τc relationship in the Wilson model. The b0-b1 and kd-τc relationships followed power law relationships. This research supports the applicability of the nonlinear mechanistic detachment model for noncohesive gravels. DA - 2016/2/17/ PY - 2016/2/17/ DO - 10.13031/trans.59.11490 VL - 59 IS - 1 SP - 145-151 SN - 2151-0032 2151-0040 UR - http://dx.doi.org/10.13031/trans.59.11490 ER - TY - JOUR TI - Correlating Site-Scale Erodibility Parameters from Jet Erosion Tests to Soil Physical Properties AU - Daly, E.R. AU - Fox, G.A. AU - Fox, A.K. T2 - Transactions of the ASABE AB - Abstract. One of the most commonly used methods of measuring erodibility parameters, i.e., critical shear stress (τc) and erodibility coefficient (kd), of cohesive soils is the Jet Erosion Test (JET). While numerous factors influence the erodibility parameters, the JET provides an in situ measurement technique. However, in many cases where erodibility parameters are required for simulating channel erosion processes, the erodibility parameters are not characterized in situ but estimated empirically based on soil physical properties with relationships that may not be good predictors for all streambanks. The objectives of this study were to investigate the correlation between the erodibility parameters measured with JETs and soil physical properties at a site-specific scale and across three unique streambanks. A total of 74 JETs were conducted within visually homogeneous streambank layers at three sites in Oklahoma along with measurements of soil physical parameters such as texture, bulk density, moisture content, and water and soil temperatures. At the site scale, τc and kd varied by up to three orders of magnitude. Neither multiple linear regressions nor principal components regressions suggested any consistent strongly correlated variables. Therefore, erodibility parameters measured in this study could not be predicted based solely on soil physical properties. It was concluded that τc and kd must be measured in situ and cannot be estimated from empirical relationships due to the heterogeneous nature of soil and the variability in subaerial processes, even within visually homogeneous streambank layers. More research is needed in order to correlate erodibility parameters to other soil parameters and quantify the role of subaerial processes, such as seepage, soil desiccation, and freeze-thaw cycles, on erodibility in order to incorporate spatial variability of erodibility parameters into stability and channel evolution models. DA - 2016/2/17/ PY - 2016/2/17/ DO - 10.13031/trans.59.11309 VL - 59 IS - 1 SP - 115-128 SN - 2151-0032 2151-0040 UR - http://dx.doi.org/10.13031/trans.59.11309 ER - TY - JOUR TI - Heterogeneity influences on stream water–groundwater interactions in a gravel-dominated floodplain AU - Miller, R.B. AU - Heeren, D.M. AU - Fox, G.A. AU - Halihan, T. AU - Storm, D.E. T2 - Hydrological Sciences Journal AB - Floodplains are composed of complex depositional patterns of ancient and recent stream sediments, and research is needed to address the manner in which coarse floodplain materials affect stream–groundwater exchange patterns. Efforts to understand the heterogeneity of aquifers have utilized numerous techniques typically focused on point-scale measurements; however, in highly heterogeneous settings, the ability to model heterogeneity is dependent on the data density and spatial distribution. The objective of this research was to investigate the correlation between broad-scale methodologies for detecting heterogeneity and the observed spatial variability in stream/groundwater interactions of gravel-dominated alluvial floodplains. More specifically, this study examined the correlation between electrical resistivity (ER) and alluvial groundwater patterns during a flood event at a site on Barren Fork Creek, in the Ozark ecoregion of Oklahoma, USA, where chert gravels were common both as streambed and as floodplain material. Water table elevations from groundwater monitoring wells for a flood event on 1–5 May 2009 were compared to ER maps at various elevations. Areas with high ER matched areas with lower water table slope at the same elevation. This research demonstrated that ER approaches were capable of indicating heterogeneity in surface water–groundwater interactions, and that these heterogeneities were present even in an aquifer matrix characterized as highly conductive. Portions of gravel-dominated floodplain vadose zones characterized by high hydraulic conductivity features can result in heterogeneous flow patterns when the vadose zone of alluvial floodplains activates during storm events. EDITOR D. Koutsoyiannis; ASSOCIATE EDITOR X. Chen DA - 2016/2/3/ PY - 2016/2/3/ DO - 10.1080/02626667.2014.992790 VL - 61 IS - 4 SP - 741-750 J2 - Hydrological Sciences Journal LA - en OP - SN - 0262-6667 2150-3435 UR - http://dx.doi.org/10.1080/02626667.2014.992790 DB - Crossref KW - alluvial floodplain KW - surface water-groundwater interaction KW - hydraulic conductivity KW - interpolations KW - streamflow KW - water table response ER - TY - JOUR TI - Evaluation of a universal flow-through model for predicting and designing phosphorus removal structures AU - Penn, Chad AU - Bowen, James AU - McGrath, Joshua AU - Nairn, Robert AU - Fox, Garey AU - Brown, Glenn AU - Wilson, Stuart AU - Gill, Clinton T2 - Chemosphere AB - Phosphorus (P) removal structures have been shown to decrease dissolved P loss from agricultural and urban areas which may reduce the threat of eutrophication. In order to design or quantify performance of these structures, the relationship between discrete and cumulative removal with cumulative P loading must be determined, either by individual flow-through experiments or model prediction. A model was previously developed for predicting P removal with P sorption materials (PSMs) under flow-through conditions, as a function of inflow P concentration, retention time (RT), and PSM characteristics. The objective of this study was to compare model results to measured P removal data from several PSM under a range of conditions (P concentrations and RT) and scales ranging from laboratory to field. Materials tested included acid mine drainage residuals (AMDRs), treated and non-treated electric arc furnace (EAF) steel slag at different size fractions, and flue gas desulfurization (FGD) gypsum. Equations for P removal curves and cumulative P removed were not significantly different between predicted and actual values for any of the 23 scenarios examined. However, the model did tend to slightly over-predict cumulative P removal for calcium-based PSMs. The ability of the model to predict P removal for various materials, RTs, and P concentrations in both controlled settings and field structures validate its use in design and quantification of these structures. This ability to predict P removal without constant monitoring is vital to widespread adoption of P removal structures, especially for meeting discharge regulations and nutrient trading programs. DA - 2016/5// PY - 2016/5// DO - 10.1016/j.chemosphere.2016.02.105 VL - 151 SP - 345-355 J2 - Chemosphere LA - en OP - SN - 0045-6535 UR - http://dx.doi.org/10.1016/J.CHEMOSPHERE.2016.02.105 DB - Crossref KW - Phosphorus KW - Phosphorus removal structures KW - Phosphorus sorption materials KW - Flow-through model KW - Eutrophication KW - Legacy phosphorus ER - TY - JOUR TI - Comparison of Linear and Nonlinear Models for Cohesive Sediment Detachment: Rill Erosion, Hole Erosion Test, and Streambank Erosion Studies AU - Khanal, A. AU - Klavon, K. R. AU - Fox, G. A. AU - Daly, E. R. T2 - Journal of Hydraulic Engineering AB - Cohesive sediment detachment is typically modeled for channels, levees, spillways, earthen dams, and internal erosion by using a linear excess shear stress approach. However, mechanistic nonlinear detachment models, such as the Wilson model, have recently been proposed in the literature. Questions exist as to the appropriateness of nonlinear relationships between applied shear stress and the erosion rate. Therefore, the objective of this research was to test the appropriateness of linear and nonlinear detachment models for cohesive sediment detachment using three data sets: (1) rill erodibility studies across a limited range of applied shear stress (0.9–21.4 Pa), (2) hole erosion tests (HETs) across a wide range of applied shear stress (12.6–62.0 Pa), and (3) streambank erodibility as quantified by jet erosion tests (JETs) for the linear excess shear stress equation and the nonlinear Wilson model across a small range of shear stress (1–4 Pa). The Wilson model was also incorporated into the bank stability and toe erosion model (BSTEM) as an option for simulating fluvial erosion and used to simulate bank retreat in the streambank erodibility study. The Wilson model was shown to be an appropriate particle detachment rate model from previously published data on rill erodibility, HETs, and JETs. Using a nonlinear detachment model also alleviated questions about the most appropriate solution technique for deriving erodibility parameters from JETs. In situ and laboratory tests sometimes use a limited range of applied shear stress, and therefore users of these measurement techniques should be aware of the potential nonlinear behavior of cohesive sediment detachment especially at higher shear stress. The results suggest advantages for the nonlinear Wilson detachment model and also identify the need for additional research to evaluate the various detachment models for laboratory HETs and in situ JETs across a wider range of soil types and additional reach-scale streambank erosion studies. DA - 2016/9// PY - 2016/9// DO - 10.1061/(ASCE)HY.1943-7900.0001147 VL - 142 IS - 9 SP - 04016026 J2 - J. Hydraul. Eng. LA - en OP - SN - 0733-9429 1943-7900 UR - http://dx.doi.org/10.1061/(ASCE)HY.1943-7900.0001147 DB - Crossref KW - Cohesive sediment KW - Erosion KW - Hole erosion test KW - Jet erosion test KW - Rill KW - Streambank ER - TY - CONF TI - Behavior of Fiber-Reinforced Sandy Slopes under Seepage AU - Akay, Onur AU - Özer, A. Tolga AU - Fox, Garey A. AU - Wilson, Glenn V. T2 - World Environmental and Water Resources Congress 2016 AB - Seepage flow is a major contributor to instability of natural hill slopes, river banks and engineered embankments. In order to increase the factor of safety, an emerging technology involves the inclusion of synthetic fibers in the soil. The addition of tension resisting fibers has a favorable effect on strength properties of sandy soils. In this study, laboratory lysimeter experiments were conducted on fiber reinforced slopes with two different values of constant pressure head boundary condition (25 and 50 cm) in the water reservoir. Fiber reinforced sand was compacted in the soil compartment of the lysimeter to obtain a slope with dimensions of 55 cm height, 20 cm width, and 100 cm base length. The gravimetric fiber content (percentage of dry weight of sand) was selected as 1% after reviewing the results of comprehensive triaxial compression tests on fiber reinforced sand specimens with varying fibrillated polypropylene fiber (12 mm long) contents from 0.1 to 1%. This study included slope stability modeling in order to quantify the global factor of safety. The triaxial compression tests indicated the increase in peak deviatoric stress with increase in fiber content. The fiber reinforced sand slope was stable against seepage conditions which would otherwise cause a shallow-seated failure of the non-remediated slope under 25 cm water pressure head. In addition, fiber reinforced sand slope maintained its global stability under 50 cm water pressure head which caused a deep-seated failure of the unreinforced slope. However, sloughing at the toe occurred under 50 and 55 cm water pressure head. C2 - 2016/5/16/ C3 - World Environmental and Water Resources Congress 2016 DA - 2016/5/16/ DO - 10.1061/9780784479858.041 SP - 397-406 PB - American Society of Civil Engineers SN - 9780784479858 UR - http://dx.doi.org/10.1061/9780784479858.041 DB - Crossref ER - TY - JOUR TI - The Soil Moisture Active Passive Marena, Oklahoma, In Situ Sensor Testbed (SMAP-MOISST): Testbed Design and Evaluation of In Situ Sensors AU - Cosh, Michael H. AU - Ochsner, Tyson E. AU - McKee, Lynn AU - Dong, Jingnuo AU - Basara, Jeffrey B. AU - Evett, Steven R. AU - Hatch, Christine E. AU - Small, Eric E. AU - Steele-Dunne, Susan C. AU - Zreda, Marek AU - Sayde, Chadi T2 - Vadose Zone Journal AB - Core Ideas Soil moisture sensors have varying accuracies that can be improved with calibration. In situ sensors require scaling to improve their representativeness of large areas. Soil moisture sensors in profile have decreasing ability to accurately represent the surface soil moisture. In situ soil moisture monitoring networks are critical to the development of soil moisture remote sensing missions as well as agricultural and environmental management, weather forecasting, and many other endeavors. These in situ networks utilize a variety of sensors and installation practices, which confounds the development of a unified reference database for satellite calibration and validation programs. As part of the Soil Moisture Active Passive Mission, the Marena, Oklahoma, In Situ Sensor Testbed (SMAP‐MOISST) was initiated to perform inter‐comparisons and study sensor limitations. Soil moisture sensors that are deployed in major monitoring networks were included in the study, along with new and emerging technologies, such as the Cosmic Ray Soil Moisture Observing System (COSMOS), passive/active distributed temperature sensing (DTS), and global positioning system reflectometers (GPSR). Four profile stations were installed in May of 2010, and soil moisture was monitored to a depth of 1 m on an hourly basis. The four stations were distributed within a circular domain of approximately 600 m diameter, adequate to encompass the sensing range of COSMOS. The sensors included in the base station configuration included the Stevens Water Hydra Probe, Campbell Scientific 616 and 229, Decagon EC‐TM, Delta‐T Theta Probe, Acclima, and Sentek EnviroSMART capacitance system. In addition, the Pico TRIME system and additional time‐domain reflectometry (TDR) systems were deployed when available. It was necessary to apply site‐specific calibration to most sensors to reach an RMSE below 0.04 m 3 m −3 . For most sensor types, a single near surface sensor could be scaled to represent the areal‐average of a field domain by simple linear regression, resulting in RMSE values around 0.03 m 3 m −3 . DA - 2016/// PY - 2016/// DO - 10.2136/vzj2015.09.0122 VL - 15 IS - 4 SP - 0 LA - en OP - SN - 1539-1663 UR - http://dx.doi.org/10.2136/vzj2015.09.0122 DB - Crossref ER - TY - JOUR TI - Mapping high-resolution soil moisture and properties using distributed temperature sensing data and an adaptive particle batch smoother T2 - Water Resources Research AB - This study demonstrated a new method for mapping high-resolution (spatial: 1 m, and temporal: 1 h) soil moisture by assimilating distributed temperature sensing (DTS) observed soil temperatures at intermediate scales. In order to provide robust soil moisture and property estimates, we first proposed an adaptive particle batch smoother algorithm (APBS). In the APBS, a tuning factor, which can avoid severe particle weight degeneration, is automatically determined by maximizing the reliability of the soil temperature estimates of each batch window. A multiple truth synthetic test was used to demonstrate the APBS can robustly estimate soil moisture and properties using observed soil temperatures at two shallow depths. The APBS algorithm was then applied to DTS data along a 71 m transect, yielding an hourly soil moisture map with meter resolution. Results show the APBS can draw the prior guessed soil hydraulic and thermal properties significantly closer to the field measured reference values. The improved soil properties in turn remove the soil moisture biases between the prior guessed and reference soil moisture, which was particularly noticeable at depth above 20 cm. This high-resolution soil moisture map demonstrates the potential of characterizing soil moisture temporal and spatial variability and reflects patterns consistent with previous studies conducted using intensive point scale soil moisture samples. The intermediate scale high spatial resolution soil moisture information derived from the DTS may facilitate remote sensing soil moisture product calibration and validation. In addition, the APBS algorithm proposed in this study would also be applicable to general hydrological data assimilation problems for robust model state and parameter estimation. DA - 2016/10// PY - 2016/10// DO - 10.1002/2016wr019031 UR - http://dx.doi.org/10.1002/2016wr019031 KW - soil moisture KW - distributed temperature sensing KW - soil temperature KW - data assimilation ER - TY - JOUR TI - Calibration of soil moisture sensing with subsurface heated fiber optics using numerical simulation AU - Benítez-Buelga, Javier AU - Rodríguez-Sinobas, Leonor AU - Sánchez Calvo, Raul AU - Gil-Rodríguez, María AU - Sayde, Chadi AU - Selker, John S. T2 - Water Resources Research AB - Abstract The heat pulse probe method can be implemented with actively heated fiber optics (AHFO) to obtain distributed measurements of soil water content (θ) by using reported soil thermal responses measured by Distributed Temperature Sensing (DTS) and with a soil‐specific calibration relationship. However, most reported applications have been calibrated to homogeneous soils in a laboratory, while inexpensive efficient in situ calibration procedures useful in heterogeneous soils are lacking. Here we employed the Hydrus 2‐D/3‐D code to define a soil‐specific calibration curve. We define a 2‐D geometry of the fiber optic cable and the surrounding soil media, and simulate heat pulses to capture the soil thermal response at different soil water contents. The model was validated in an irrigated field using DTS data from two locations along the FO deployment in which reference moisture sensors were installed. Results indicate that θ was measured with the model‐based calibration with accuracy better than 0.022 m 3 m −3 . DA - 2016/4// PY - 2016/4// DO - 10.1002/2015wr017897 VL - 52 IS - 4 SP - 2985-2995 J2 - Water Resour. Res. LA - en OP - SN - 0043-1397 UR - http://dx.doi.org/10.1002/2015WR017897 DB - Crossref ER - TY - JOUR TI - The National Air Emissions Monitoring study's southeast layer site: Part V. Hydrogen sulfide and volatile organic compounds AU - Wang, K.-Y. AU - Li, Q.-F. AU - Wang-Li, L. AU - Cortus, E.L. AU - Bogan, B.W. AU - Kilic, I. AU - Liang, W.-Z. AU - Xiao, C.-H. AU - Chai, L.-L. AU - Ni, J.-Q. AU - Heber, A.J. T2 - Transactions of the ASABE AB - Aerial pollutants generated from intensive poultry and livestock production raise concerns of health and welfare for the surrounding communities. This article reports emission rates of hydrogen sulfide (H2S) and concentrations of volatile organic compounds (VOCs) from two tunnel-ventilated high-rise houses at a layer site in North Carolina that were tested by the National Air Emissions Monitoring Study (NAEMS). Hydrogen sulfide concentrations exhibited significant seasonal and diurnal variations. The minimum and maximum average hourly mean (AHM) concentrations by hour of day occurred at 15:00-16:00 and 6:00-7:00, respectively. The lowest and highest daily mean concentrations during the annual cycle were observed in summer and winter, respectively. The AHM H2S concentrations were 1.04 ±0.83 ppb for inlet air and 9.52 ±6.35 and 9.43 ±6.01 ppb, respectively, for exhaust air from the two production houses. The diurnal and seasonal patterns of H2S emission rates from the two production houses were also similar. Slight increases in H2S emission rates occurred at 12:00 to 14:00. Higher H2S emission rates occurred in summer. The AHM hen-specific H2S emission rates from the two production houses were 618 ±517 and 698 ±620 μg d-1 hen-1, respectively. Factors significantly affecting H2S emissions were hen activity, house exhaust air temperature, and ambient air temperature. Time-integrated samples of VOCs were collected over 24 h periods seven times in one production house from 12 April 2009 to 18 September 2009. Of 77 target compounds, the ten most abundant compounds were 2-butanone, iso-propanol, dimethyl sulfide, hexanal, acetic acid, 2,3-butanedione, pentane, acetaldehyde, pentanal, and phenol. Differences in VOC concentrations were observed between the layer room and the manure pit. The highest total VOC concentration was detected in samples taken from the manure pit exhaust air. DA - 2016/// PY - 2016/// DO - 10.13031/trans.59.11150 VL - 59 IS - 2 SP - 681-693 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84964758698&partnerID=MN8TOARS ER - TY - JOUR TI - Performance analysis of a poultry engineering chamber complex for animal environment, air quality, and welfare studies AU - Padavagod Shivkumar, A. AU - Wang-Li, L. AU - Shah, S.B. AU - Stikeleather, L.F. AU - Fuentes, M. T2 - Transactions of the ASABE AB - Abstract. Studies of animal welfare and air quality require good understanding of the production environment. This study evaluated the performance of a dedicated poultry engineering chamber complex (PECC) designed to conduct studies for enhancement in poultry production, air quality, and animal welfare. The performance evaluation of the PECC was carried out by direct flow testing and computational fluid dynamics (CFD) modeling. The flow rate measurements at six different blower speeds () in each of the six chambers and the corresponding pressure drops across the system indicated the effects of structural geometry and components on the flow characteristics. There was no significant difference in mean flow rate among chambers (p = 0.956). The flow in the animal-occupied zone (core chamber) was simulated using CFD, and the results were validated using field measurements. The average air velocities at bird height at blower speeds of 600 and 1200 obtained using direct measurements were 0.794 ±0.15 m s-1 and 1.706 ±0.305 m s-1, respectively, and the average air velocities obtained using CFD models were 0.809 ±0.169 m s-1 and 1.642 ±0.395 m s-1, respectively. Error analysis at each measurement point indicated a maximum value of 13.59% at bird height due to the presence of feeders. Statistical analysis showed no significant difference between measured and simulated results (p = 0.5415). The normalized mean square error was 0.007, indicating good agreement of simulated results with measurements. Certain regions in the animal-occupied zone had lower air velocity on average and therefore higher mean surface temperature of bird models in those regions, caused by the flocking effect. DA - 2016/// PY - 2016/// DO - 10.13031/trans.59.11402 VL - 59 IS - 5 SP - 1371-1382 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84998775201&partnerID=MN8TOARS KW - Air velocity KW - Animal environment KW - CFD KW - Flow testing KW - Poultry engineering chamber KW - Ventilation ER - TY - JOUR TI - Interpreting and Designing Microbial Communities for Bioprocess Applications, from Components to Interactions to Emergent Properties AU - Beck, A.E. AU - Hunt, K.A. AU - Bernstein, H.C. AU - Carlson, R.P. T2 - Biotechnology for Biofuel Production and Optimization AB - Interest in microbial communities for bioprocessing has surged in recent years based on the potential to optimize multiple tasks simultaneously and to enhance process productivity and stability. The presence and magnitude of these desirable properties often result from interactions between community members. The importance of interactions has gained interest due to improving omics techniques, polymicrobial culturing approaches, and computational methods, which have made the systems-level analysis of interacting components more tractable. This review defines and categorizes natural and engineered system components, interactions, and emergent properties, as well as presents three ecological theories relevant to microbial communities. Case studies are interpreted to illustrate components, interactions, emergent properties, and theoretical context. A general foundation is laid to facilitate interpretation of current systems and to aid the design of next generation bioprocesses. DA - 2016/// PY - 2016/// DO - 10.1016/b978-0-444-63475-7.00015-7 SP - 407-432 ER - TY - CONF TI - Spatially-explicit methodology for manure management at the watershed level AU - Sharara, Mahmoud AU - Larson, Rebecca AU - Runge, Troy T2 - American Society of Agricultural and Biological Engineers C2 - 2016/// C3 - 2016 ASABE Annual International Meeting DA - 2016/// SP - 1 ER - TY - CONF TI - Techno-economic assessment of dairy manure granulation AU - Sharara, Mahmoud AU - Yang, Qiang AU - Cox, Thomas L AU - Runge, Troy M T2 - American Society of Agricultural and Biological Engineers C2 - 2016/// C3 - 2016 ASABE Annual International Meeting DA - 2016/// SP - 1 ER - TY - JOUR TI - Effects of large-scale manure treatment processes on pathogen reduction, protein distributions, and nutrient concentrations AU - Liu, Zong AU - Sharara, Mahmoud AU - Gunasekaran, Sundaram AU - Runge, Troy M T2 - Transactions of the ASABE DA - 2016/// PY - 2016/// VL - 59 IS - 2 SP - 695-702 ER - TY - JOUR TI - Combustion kinetics of swine manure and algal solids AU - Sharara, Mahmoud A AU - Sadaka, Sammy S AU - Costello, Thomas A AU - VanDevender, Karl AU - Carrier, Julie AU - Popp, Michael AU - Thoma, Greg AU - Djioleu, Angele T2 - Journal of Thermal Analysis and Calorimetry DA - 2016/// PY - 2016/// VL - 123 IS - 1 SP - 687-696 ER - TY - JOUR TI - Carbon Footprint - Tips for Arkansas Producers AU - Sadaka, Sammy AU - Sharara, Mahmoud DA - 2016/// PY - 2016/// ER - TY - JOUR TI - Hydrological modelling in forested systems AU - Golden, H. E. AU - Evenson, G. R. AU - Tian, S. AU - Amatya, D. M. AU - Sun, G. T2 - Forest Hydrology: Processes, Management and Assessment AB - This chapter provides a brief overview of forest hydrology modelling approaches for answering important global research and management questions. Many hundreds of hydrological models have been applied globally across multiple decades to represent and predict forest hydrological processes. The focus of this chapter is on process-based models and approaches, specifically 'forest hydrology models'; that is, physically based simulation tools that quantify compartments of the forest hydrological cycle. Physically based models can be considered those that describe the conservation of mass, momentum and/or energy. DA - 2016/// PY - 2016/// DO - 10.1079/9781780646602.0141 SP - 141-161 ER - TY - JOUR TI - Forest drainage AU - Skaggs, R. W. AU - Tian, S. AU - Chescheir, G. M. AU - Amatya, D. M. AU - Youssef, M. A. T2 - Forest Hydrology: Processes, Management and Assessment AB - This chapter reviews the impacts of drainage on forest production and the hydrology of forested lands. It is established that drainage is used to improve access and yields on a small percentage of the world's forested lands. However, it has had a big impact on the millions of hectares on which it is applied. Drainage has increased timber yields on poorly drained peatlands and mineral soils in northern Europe, Canada and the southern USA. DA - 2016/// PY - 2016/// DO - 10.1079/9781780646602.0124 SP - 124-140 ER - TY - CONF TI - The Restoration of James Brindley’s Last Canal and the Serious Threat from 21st Century Transport Infrastructure Developments AU - Newman, Alan P. AU - Hunt, William F. T2 - World Environmental and Water Resources Congress 2016 AB - James Brindley is widely recognised as a pioneer of the British canal system. His last project was the proposal to provide a waterway from Chesterfield to the River Trent from where the local iron, coal and lead could be transported to their principal markets in London. By 1769 a route had been surveyed charting a course which indicated a move away from the earlier “contour following canals” to the much more ambitious routes taken by later British canals. This included the longest canal tunnel in Britain and extensive use of multi-flight locks. In 1907, the tunnel collapsed due to mining subsidence, never to be reopened. The inland section fell into disrepair and was in-filled in places. This paper reports the efforts of volunteer bodies to reopen the canal, including a proposed ambitious engineering task to by-pass the collapsed tunnel. With funding streams identified, an announcement about a new high-speed rail line which will impact on the canal has brought funding streams to a halt. This paper will also highlight how the opportunity to restore to use, one of the most important heritage projects in the U.K., may have been lost but will also show how history shows that rail developments need not bring us to the end of the line. C2 - 2016/5/16/ C3 - World Environmental and Water Resources Congress 2016 DA - 2016/5/16/ DO - 10.1061/9780784479841.014 SP - 124-133 PB - American Society of Civil Engineers SN - 9780784479841 UR - http://dx.doi.org/10.1061/9780784479841.014 DB - Crossref ER - TY - JOUR TI - The Genetic architecture of quantitative traits cannot be inferred from variance component analysis AU - Huang, W. AU - Mackay, T. F. C. T2 - PLoS Genetics AB - Abstract Classical quantitative genetic analyses estimate additive and non-additive genetic and environmental components of variance from phenotypes of related individuals. The genetic variance components are defined in terms of genotypic values reflecting underlying genetic architecture (additive, dominance and epistatic genotypic effects) and allele frequencies. However, the dependency of the definition of genetic variance components on the underlying genetic models is not often appreciated. Here, we show how the partitioning of additive and non-additive genetic variation is affected by the genetic models and parameterization of allelic effects. We show that arbitrarily defined variance components often capture a substantial fraction of total genetic variation regardless of the underlying genetic architecture in simulated and real data. Therefore, variance component analysis cannot be used to infer genetic architecture of quantitative traits. The genetic basis of quantitative trait variation in a natural population can only be defined empirically using high resolution mapping methods followed by detailed characterization of QTL effects. DA - 2016/// PY - 2016/// DO - 10.1101/041434 VL - 12 IS - 11 ER - TY - JOUR TI - Performance analysis of a poultry engineering chamber complex for animal environment, air quality, and welfare studies AU - Shivkumar, A. P. AU - Wang-Li, L. AU - Shah, S. B. AU - Stikeleather, L. F. AU - Fuentes, M. T2 - Transactions of the ASABE DA - 2016/// PY - 2016/// VL - 59 IS - 5 SP - 1371-1382 ER - TY - JOUR TI - Optimization of ultrasound-induced microalgal lipid recovery AU - Wang, M. AU - Yuan, W. AU - Luo, G. AU - Liu, Y. T2 - Transactions of the ASABE DA - 2016/// PY - 2016/// VL - 59 IS - 5 SP - 1459-1465 ER - TY - JOUR TI - N2O EMISSION AND NITROGEN TRANSFORMATION IN CHICKEN MANURE AND BIOCHAR CO-COMPOSTING AU - Jia, X. AU - Wang, M. AU - Yuan, W. AU - Shah, S. AU - Shi, W. AU - Meng, X. AU - Ju, X. AU - Yang, B. T2 - TRANSACTIONS OF THE ASABE AB - This study examined the effect of biochar addition on nitrous oxide (N2O) emission and nitrogen (N) transformation in co-composting of biochar and chicken manure. Compared with the control (no biochar), addition of 20% biochar resulted in a 59.8% decrease in the major peak of N2O emission. Ammonium (NH4+-N) and nitrate (NO3--N) contents in the final product with 20% biochar addition increased by 67.3% and 66.7%, respectively, compared to the control. Turning frequency (TF), the primary parameter of aeration and temperature control in the biochar-manure co-composting process, was also investigated. Results indicated that less frequent turning (e.g., turning every seven days) promoted NH4+-N and NO3-N retention but increased peak N2O emission by 58.1% compared with daily turning. Overall, biochar can be an ideal bulking agent for stabilizing N-rich materials to minimize N2O emission and, with proper aeration, can enhance nitrogen retention based on this laboratory study. DA - 2016/// PY - 2016/// DO - 10.13031/trans.59.11685 VL - 59 IS - 5 SP - 1277-1283 SN - 2151-0040 KW - Biochar KW - Chicken manure KW - Co-composting KW - N2O emission KW - Nitrogen transformation ER - TY - JOUR TI - First report of a novel multiplexer pumping system coupled to a water quality probe to collect high temporal frequency in situ water chemistry measurements at multiple sites AU - Birgand, François AU - Aveni-Deforge, Kyle AU - Smith, Brad AU - Maxwell, Bryan AU - Horstman, Marc AU - Gerling, Alexandra B. AU - Carey, Cayelan C. T2 - Limnology and Oceanography: Methods AB - The increasing availability and use of high-frequency water quality sensors has enabled unprecedented observations of temporal variability in water chemistry in aquatic ecosystems. However, we remain limited by the prohibitive costs of these probes to explore spatial variability in natural systems. To overcome this challenge, we have developed a novel auto-sampler system that sequentially pumps water from up to 12 different sites located within a 12 m radius to a single water quality probe. This system is able to generate high temporal frequency in situ water chemistry data from multiple replicated units during experiments as well as multiple sites and depths within natural aquatic ecosystems. Thus, with one water quality probe, we are able to observe rapid changes in water chemistry concentrations over time and space. Here, we describe the coupled multiplexer-probe system and its performance in two case studies: a mesocosm experiment examining the effects of water current velocity on nitrogen dynamics in constructed wetland sediment cores and a whole-ecosystem manipulation of redox conditions in a reservoir. In both lotic and lentic case studies, we observed minute-scale changes in nutrient concentrations, which provide new insight on the variability of biogeochemical processes. Moreover, in the reservoir, we were able to measure rapid changes in metal concentrations, in addition to those of nutrients, in response to changes in redox. Consequently, we believe that this coupled system holds great promise for measuring biogeochemical fluxes in a diverse suite of aquatic ecosystems and experiments. DA - 2016/7/29/ PY - 2016/7/29/ DO - 10.1002/lom3.10122 VL - 14 IS - 12 SP - 767-783 J2 - Limnol. Oceanogr. Methods LA - en OP - SN - 1541-5856 UR - http://dx.doi.org/10.1002/lom3.10122 DB - Crossref ER - TY - JOUR TI - The Genetics of Leaf Flecking in Maize and Its Relationship to Plant Defense and Disease Resistance AU - Olukolu, Bode A. AU - Bian, Yang AU - De Vries, Brian AU - Tracy, William F. AU - Wisser, Randall J. AU - Holland, James B. AU - Balint-Kurti, Peter J. T2 - Plant Physiology AB - Physiological leaf spotting, or flecking, is a mild-lesion phenotype observed on the leaves of several commonly used maize (Zea mays) inbred lines and has been anecdotally linked to enhanced broad-spectrum disease resistance. Flecking was assessed in the maize nested association mapping (NAM) population, comprising 4,998 recombinant inbred lines from 25 biparental families, and in an association population, comprising 279 diverse maize inbreds. Joint family linkage analysis was conducted with 7,386 markers in the NAM population. Genome-wide association tests were performed with 26.5 million single-nucleotide polymorphisms (SNPs) in the NAM population and with 246,497 SNPs in the association population, resulting in the identification of 18 and three loci associated with variation in flecking, respectively. Many of the candidate genes colocalizing with associated SNPs are similar to genes that function in plant defense response via cell wall modification, salicylic acid- and jasmonic acid-dependent pathways, redox homeostasis, stress response, and vesicle trafficking/remodeling. Significant positive correlations were found between increased flecking, stronger defense response, increased disease resistance, and increased pest resistance. A nonlinear relationship with total kernel weight also was observed whereby lines with relatively high levels of flecking had, on average, lower total kernel weight. We present evidence suggesting that mild flecking could be used as a selection criterion for breeding programs trying to incorporate broad-spectrum disease resistance. DA - 2016/9/26/ PY - 2016/9/26/ DO - 10.1104/pp.15.01870 VL - 172 IS - 3 SP - 1787-1803 J2 - Plant Physiol. LA - en OP - SN - 0032-0889 1532-2548 UR - http://dx.doi.org/10.1104/pp.15.01870 DB - Crossref ER - TY - JOUR TI - Greenhouse Gas Emissions from a Created Brackish Marsh in Eastern North Carolina AU - Shiau, Yo-Jin AU - Burchell, Michael R. AU - Krauss, Ken W. AU - Birgand, Francois AU - Broome, Stephen W. T2 - Wetlands DA - 2016/9/10/ PY - 2016/9/10/ DO - 10.1007/s13157-016-0815-y VL - 36 IS - 6 SP - 1009-1024 J2 - Wetlands LA - en OP - SN - 0277-5212 1943-6246 UR - http://dx.doi.org/10.1007/s13157-016-0815-y DB - Crossref KW - Brackish marsh creation KW - Greenhouse gas emission KW - Carbon dioxide KW - Methane KW - Carbon sequestration ER - TY - JOUR TI - Evaluating the spatial distribution of pollutants and associated maintenance requirements in an 11 year-old bioretention cell in urban Charlotte, NC AU - Johnson, Jeffrey P. AU - Hunt, William F. T2 - JOURNAL OF ENVIRONMENTAL MANAGEMENT AB - Bioretention cells (BRCs) are an increasingly popular Stormwater Control Measure used to mitigate the hydrologic and water quality impacts of urbanization. Previous BRC research has demonstrated a strong capacity for pollutant removal; however, long-term sequestration of pollutants within soil media can elevate concentrations to levels fostering environmental and human health risks. Soil media samples were collected from an 11 year-old BRC in Charlotte, NC, and analyzed for the accumulation and spatial distribution of zinc, copper, and phosphorus. Pollutant distribution varied significantly with respect to depth and ordinate distance from the BRC inlet. Zinc concentrations (0.9–228.6 mg kg−1 soil) exceeded environmental thresholds and phosphorus concentrations (5.1–173.3 mg kg−1 soil) increased from initial levels by a factor of seven; however, notable accumulation was restricted to the BRC forebay. Maximum zinc and copper concentrations in soil media did not exceed 1% of mandatory cleanup levels and with regular maintenance of the forebay, the effective life of BRC media should exceed the life of the developments they treat. DA - 2016/12/15/ PY - 2016/12/15/ DO - 10.1016/j.jenvman.2016.10.009 VL - 184 SP - 363-370 SN - 1095-8630 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84994339362&partnerID=MN8TOARS KW - Stormwater management KW - Bioretention KW - Heavy metals KW - Water pollution KW - Bioinfiltration KW - Stormwater maintenance KW - Phosphorus ER - TY - JOUR TI - Volume Reduction Provided by Eight Residential Disconnected Downspouts in Durham, North Carolina AU - Carmen, N. B. AU - Hunt, William F. AU - Anderson, A. R. T2 - Journal of Environmental Engineering AB - One major concern of increased development is the proportion of directly connected impervious areas (DCIA) in urbanized watersheds. A cost-efficient opportunity to treat stormwater within existing residential and small-scale commercial developments is to disconnect roof gutter downspouts and direct impervious surface runoff over lawns. Four paired residential downspout disconnection sites in Durham, North Carolina, were studied to quantify volume and peak flow reduction. Hydrologic data were collected from January 22, 2013, to October 8, 2013. For each site, the performance of disconnected downspouts discharging water over existing lawn was compared for three varying factors: slope of lawn, length of run over lawn, and proportion of contributing roof area to receiving lawn area. Data were analyzed from approximately 60 storm events. Performance was evaluated by calculating volume reduction with and without the direct rainfall on the lawn, resulting in cumulative runoff volume reduction ranges of 57–99% and 49–99%, respectively. Findings indicate that this simple and inexpensive stormwater control measure (SCM) might be an important, yet heretofore minimally accounted for, tool to mitigate runoff. DA - 2016/10// PY - 2016/10// DO - 10.1061/(ASCE)EE.1943-7870.0001107 VL - 142 IS - 10 SP - 05016002 J2 - J. Environ. Eng. LA - en OP - SN - 0733-9372 1943-7870 UR - http://dx.doi.org/10.1061/(ASCE)EE.1943-7870.0001107 DB - Crossref KW - Downspout disconnection KW - Low-impact development KW - Impervious surface disconnection KW - Directly connected impervious area KW - Stormwater ER - TY - JOUR TI - Removal of Ammonia and Airborne Culturable Bacteria by Proof-of-Concept Windbreak Wall with Slightly Acidic Electrolyzed Water Spray for a Layer Breeding House AU - Zheng, Weichao AU - Li, Zonggang AU - Shah, Sanjay B. AU - Li, Baoming T2 - Applied Engineering in Agriculture AB - Abstract. Air contaminants emitted from animal buildings may harm the environment and public health. A windbreak wall with slightly acidic electrolyzed water (SAEW) sprayed downwind of the exhaust fans offers a potential approach for the removal of some of these air contaminants, including ammonia and airborne culturable bacteria (CB). This study was conducted to investigate the removal efficiency of ammonia and airborne CB by a proof-of-concept windbreak wall with SAEW spray for a layer breeding house. A windbreak wall with spraying system was placed downwind of an exhaust fan. Tap water and SAEW, a novel environment-friendly disinfectant, were used in the spraying system. Separate sampling manifolds for ammonia and airborne CB were placed at the inlet and the outlet of the windbreak wall, respectively, for ammonia and CB sampling. The windbreak wall with water spray and 70 mg L-1 (available chlorine concentration) SAEW spray both significantly reduced ammonia emissions from the house though the removal was small. The 70 mg L-1 SAEW spray showed a numerically higher ammonia removal efficiency (13.2%) than water spray (8.8%), but no significant difference was found (p = 0.13). The windbreak wall with 70 mg L-1 and 100 mg L-1 SAEW spray both significantly and moderately reduced airborne CB emission from the layer breeding house (p < 0.01) but the two SAEW concentrations yielded similar removal efficiencies (~40%). Additional design improvements are needed to increase the removal efficiency of pollutants. An improved windbreak wall with SAEW spray could be a promising technique for reducing emissions from animal houses. DA - 2016/6/7/ PY - 2016/6/7/ DO - 10.13031/aea.32.11509 VL - 32 IS - 3 SP - 393–399 SN - 0883-8542 1943-7838 UR - http://dx.doi.org/10.13031/aea.32.11509 KW - Bioaerosol KW - Emission KW - Poultry KW - Scrubber ER - TY - JOUR TI - INJURY AND RECOVERY OF MAIZE ROOTS AFFECTED BY FLOODING AU - McDaniel, V. AU - Skaggs, R. W. AU - Negm, L. M. T2 - APPLIED ENGINEERING IN AGRICULTURE AB - Proper soil environment for adequate root growth is crucial to maintain crop yields. Excessively wet soil conditions cause poor root growth and restrict plant water and nutrient uptake. The purpose of this study was to investigate corn root response to flooding and the root system ability to recover after saturation. Corn plants were grown in 1.3 m tall acrylic cylinders under controlled conditions. Plants were subjected to flooding for 1, 3, or 5 days at growth stages V4, V8, V12, and R1. Data were collected throughout the growing season on: root growth, root depth, and root mass. Root mortality was noted after the flooding treatment. Roots responded quickly to saturation (flooding) and all growth ceased within 24 h. Recovery to normal growth rates occurred within five days unless the saturation caused severe plant damage. One day of flooding did not affect root mass at any stage of growth. Root mass was not affected by three days of flooding during the V4 and V8 stages. A significant reduction of root mass was noted for more than 35 days following 3-day inundation during V12 and R1. Flooding for five days during stage V4, V12, and R1 caused a significant reduction in root mass. Plants flooded during V8 suffered no significant reduction in root mass. Assessment of root response to saturated soil conditions is necessary to improve groundwater table management practices in high water table soils, as well as to enhance the performance of simulation model that predict plant growth and yield on drained lands. DA - 2016/// PY - 2016/// DO - 10.13031/aea.32.11633 VL - 32 IS - 5 SP - 627-638 SN - 1943-7838 KW - Root growth KW - Flooding KW - Corn KW - Root mortality KW - Plant recovery ER - TY - JOUR TI - A Simple Infiltration Test for Determination of Permeable Pavement Maintenance Needs AU - Winston, Ryan J. AU - Al-Rubaei, Ahmed M. AU - Blecken, Godecke T. AU - Hunt, William F. T2 - Journal of Environmental Engineering AB - Permeable pavements allow stormwater to pass through the pavement surface, filtering out sediment and debris; over time, regular preventative maintenance will be needed to maintain the pavement surface infiltration rate (IR). IR testing is commonly used to determine maintenance needs and frequencies. ASTM standard methods may be used to measure permeable pavement IR; however, these tests can take hours to complete and require infiltrometers not readily available to maintenance contractors. A simple infiltration test (SIT) has been devised which (1) is conducted using easily acquired materials, (2) has a larger surface area (i.e., more representative of average pavement conditions), and (3) requires, on average, 72% less time to conduct than the ASTM test. ASTM and SIT methods were compared by conducting a total of 873 IR tests at the same locations on 12 permeable pavements in North Carolina, Ohio, and Sweden. Results showed that (1) a segmented linear relationship related SIT and ASTM-measured IRs; (2) the SIT and ASTM tests predicted approximately the same IR up to 250 mm/min; (3) the larger surface area of the SIT reduced the variability in measurements (average 40% less) compared to the ASTM method. The SIT took one-quarter the time to run, on average, making this newly-devised tool more efficient when assessing IR than ASTM methods, potentially saving maintenance personnel time and money. DA - 2016/10// PY - 2016/10// DO - 10.1061/(ASCE)EE.1943-7870.0001121 VL - 142 IS - 10 SP - 06016005 J2 - J. Environ. Eng. LA - en OP - SN - 0733-9372 1943-7870 UR - http://dx.doi.org/10.1061/(ASCE)EE.1943-7870.0001121 DB - Crossref KW - Clogging KW - Hydraulics KW - Infiltration rate KW - Pervious asphalt KW - Porous concrete KW - Permeable interlocking concrete pavers KW - Pervious pavement ER - TY - JOUR TI - Effects of selenite on chlorophyll fluorescence, starch content and fatty acid in the duckweed Landoltia punctata AU - Zhong, Yu AU - Li, Yang AU - Cheng, Jay J. T2 - JOURNAL OF PLANT RESEARCH DA - 2016/9// PY - 2016/9// DO - 10.1007/s10265-016-0848-6 VL - 129 IS - 5 SP - 997-1004 SN - 1618-0860 KW - Duckweed KW - Selenium KW - Chlorophyll fluorescence KW - Starch KW - Fatty acid ER - TY - JOUR TI - Effectiveness of Livestock Exclusion in a Pasture of Central North Carolina AU - Line, Daniel E. AU - Osmond, Deanna L. AU - Childres, Wesley T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Reducing the export of nitrogen (N), phosphorus (P), and sediment from agricultural land in water‐supply watersheds is a continuing goal in central North Carolina. The objective of this project was to document the effectiveness of a combination of livestock exclusion fencing and nutrient management implemented on a beef cattle pasture located in the Piedmont region of North Carolina. The quantity and quality of discharge from two predominantly pasture watersheds were monitored simultaneously for 3.8 yr before and after implementation of the exclusion fencing and nutrient management in the treatment watershed; a control watershed remained unchanged. The excluded stream corridor was intentionally minimized by constructing the fence line about 3 m from the top of the streambank on either side and limiting it to the main stream channel only. Monitoring included collecting flow‐proportional samples during storm events and analyzing them for total Kjeldahl N (TKN), ammonia (NH 3 –N), and inorganic (NO x –N) N as well as total P (TP) and total suspended solids (TSS). Statistically significant reductions were observed in TKN (34%), NH 3 –N (54%), TP (47%), and TSS (60%) loads in the treatment relative to the control watershed after fencing, whereas storm discharge and NO x –N loads were not significantly different. These data show that even a relatively narrow exclusion corridor implemented on only the main stream channel can significantly reduce the export of N, P, and sediment from a beef cattle pasture. Core Ideas Document, through water quality monitoring, the effectiveness of livestock exclusion fencing Livestock exclusion reduced nitrogen, phosphorus, and sediment export from a pasture. Statistical analysis is required to assess trends in water quality monitoring data. DA - 2016/// PY - 2016/// DO - 10.2134/jeq2016.03.0089 VL - 45 IS - 6 SP - 1926-1932 SN - 1537-2537 ER - TY - JOUR TI - Development of MOS sensor-based NH3 monitor for use in poultry houses AU - Lin, Tianheng AU - Shah, Sanjay B. AU - Wang-Li, Lingjuan AU - Oviedo-Rondón, Edgar O. AU - Post, Justin T2 - Computers and Electronics in Agriculture AB - To ensure poultry performance and welfare, ammonia (NH3) concentrations inside poultry houses have to be within acceptable limits; this requires regular NH3 monitoring. While there are low-cost, portable NH3 measuring devices have drawbacks. Due to its low cost, long lifetime, and short response time, a metal oxide semiconductor (MOS) sensor was used to develop a handheld NH3 monitor for use in poultry houses. Since the MOS sensor is affected by humidity and temperature, collocating relative humidity (RH) and temperature sensors with the MOS NH3 sensor and applying temperature and RH compensations greatly improved its performance. Compared to the boric acid scrubber, using broiler litter exhaust gas as the NH3 source, the relative error (RE) and coefficient of variation (CV) of the monitor averaged 7%, comparable to research-grade instruments. The monitor was more accurate than the electrochemical sensor and required less frequent purging. The response time of the unit was ∼1.5 min, the total mass was <1.4 kg while material cost was <$430. Hence, in addition to being convenient, the monitor provided accurate and precise measurements. With further refinements, the monitor has the potential to be used in poultry houses to control ventilation rates as a component of precision livestock farming to improve poultry performance and welfare. DA - 2016/9// PY - 2016/9// DO - 10.1016/j.compag.2016.07.033 VL - 127 SP - 708-715 J2 - Computers and Electronics in Agriculture LA - en OP - SN - 0168-1699 UR - http://dx.doi.org/10.1016/j.compag.2016.07.033 DB - Crossref KW - Gas sensor KW - Low cost KW - Humidity compensation KW - Electrochemical sensor KW - Acid scrubber ER - TY - JOUR TI - Improvement of Acid Hydrolysis Procedures for the Composition Analysis of Herbaceous Biomass AU - Whitfield, Matthew B. AU - Chinn, Mari S. AU - Veal, Matthew W. T2 - Energy & Fuels AB - The accurate characterization of biomass is critical for development of bioenergy feedstocks and their utilization. Most analytical approaches involve acid hydrolysis of the polysaccharides in biomass, leaving most of the lignin as insoluble residue. A limitation of this approach is that the same conditions used to hydrolyze polysaccharides also degrade the liberated monosaccharides. The NREL-compiled procedures account for this effect with “Sugar Recovery Standards”, in which a solution of the expected monosaccharides is prepared and subjected to the dilute-hydrolysis portion of the procedure; however, this tends to overestimate monosaccharide degradation and introduce bias between polysaccharides of different lability. The following recommended method modifications are intended to reduce these errors: (1) quantification of immediate degradation products of monosaccharides and their stoichiometric addition to the monosaccharide yield; (2) the adjustment of this combined yield with sugar recovery standards; and (3) preautoclave analysis of hydrolyzates to improve the estimation of monosaccharide concentration profiles for adjustment calculations. DA - 2016/9/13/ PY - 2016/9/13/ DO - 10.1021/acs.energyfuels.6b01390 VL - 30 IS - 10 SP - 8260-8269 J2 - Energy Fuels LA - en OP - SN - 0887-0624 1520-5029 UR - http://dx.doi.org/10.1021/acs.energyfuels.6b01390 DB - Crossref ER - TY - JOUR TI - Enhancing Stormwater Management Benefits of Rainwater Harvesting via Innovative Technologies AU - Gee, K. D. AU - Hunt, W. F. T2 - Journal of Environmental Engineering AB - Rainwater harvesting (RWH) systems provide the dual, but often opposing, benefits of acting as alternate water supply sources and providing detention/retention of roof runoff that would otherwise become stormwater runoff. A major challenge that exists when using a RWH system to simultaneously accomplish stormwater and water-conservation benefits in nonarid regions is that these systems are often underutilized, thus remaining full a large portion of the time. For a system to mitigate stormwater runoff, however, there must be sufficient room available in the tank to store a runoff event. Two novel approaches were implemented to improve the ability of RWH systems to serve as both water-conservation practices and stormwater-management practices: an active release technology and a passive release technology. Two locations in Craven County, North Carolina, had RWH systems installed to capture roof runoff and store it for nonpotable uses. One system was equipped with the passive release mechanism, which divided the storage tank into a detention storage volume that was slowly drained between storm events, and a retention storage volume, which was retained for harvesting. The other system included an active release mechanism that automatically released harvested water based on real-time forecasted precipitation and current RWH system conditions. Despite minimal usage, both systems provided substantial stormwater mitigation. The passive release system averaged 82 and 90% volume and peak flow reductions, respectively, while the active release system reduced volumes and peak flows by an average of 91 and 93%, respectively. Both of these mechanisms exhibit great promise in revolutionizing rainwater harvesting system use to meet both water-conservation and stormwater-management goals. DA - 2016/8// PY - 2016/8// DO - 10.1061/(ASCE)EE.1943-7870.0001108 VL - 142 IS - 8 SP - 04016039 J2 - J. Environ. Eng. LA - en OP - SN - 0733-9372 1943-7870 UR - http://dx.doi.org/10.1061/(ASCE)EE.1943-7870.0001108 DB - Crossref ER - TY - JOUR TI - Different seasonality of nitrate export from an agricultural watershed and an urbanized watershed in Midwestern USA AU - Tian, S. AU - Youssef, M. A. AU - Richards, R. P. AU - Liu, J. AU - Baker, D. B. AU - Liu, Y. T2 - JOURNAL OF HYDROLOGY AB - Land use/land cover is a critical factor affecting temporal dynamics of nitrate export from watersheds. Based on a long-term (>30 years) water quality monitoring program in the Western Lake Erie area, United States, this study compared seasonal variation of nitrate export from an agricultural watershed and an urbanized watershed. A seasonality index was adapted to quantitatively characterize seasonal variation of nitrate export from the two watersheds. Results showed that monthly nitrate concentrations from the two watersheds exhibited different seasonal variation. Seasonality index of monthly nitrate loading for the agricultural watershed is approximately 3 times of that from the urbanized watershed and the difference is statistically significant (p < 0.0001). Meanwhile, calculated historical seasonality indexes of monthly nitrate loading for both watersheds exhibited significant (p < 0.05) decreasing trends according to the non-seasonal Mann-Kendall test. The identified differences in seasonal nitrate export from the two watersheds were mainly attributed to their distinct nitrogen sources, physical and biogeochemical settings. The declining seasonality index of monthly nitrate loading from the agricultural watershed could be partially caused by historical climate change in the study region, especially increased temperature during winter. Urbanization could be one key factor contributing to the declining seasonality index of monthly nitrate loading from the urbanized watershed. Information derived from this study have practical implications for developing proper management practices to mitigate nitrate pollution in Midwestern United States. DA - 2016/10// PY - 2016/10// DO - 10.1016/j.jhydrol.2016.08.042 VL - 541 SP - 1375-1384 SN - 1879-2707 KW - Land use KW - Land cover KW - Climate change KW - Nitrate export KW - Agricultural lands KW - Urbanization ER - TY - JOUR TI - Avocado seed-derived activated carbon for mitigation of aqueous ammonium AU - Zhu, Yiying AU - Kolar, Praveen AU - Shah, Sanjay B. AU - Cheng, Jay J. AU - Lim, P.K. T2 - Industrial Crops and Products AB - There is a significant interest in value-addition of agricultural residues. In the present research, a novel avocado seed-activated carbon prepared from methanesulfonic acid (denoted as AAC-MA) was systematically tested as an adsorbent for removal of ammonium for the first time. SEM characterization technique was employed to identify the structural and morphological properties of the prepared carbon. The effects of pH, adsorbent dosage, initial NH4+ concentrations, and contact time on ammonium removal from aqueous solution were also investigated. Moreover, different kinetic and isotherm models were fit to the experimental data to gain a better understanding of the efficiency and applicability of the adsorption system. The pseudo-second order kinetic model was found to best describe the ammonium adsorption. The equilibrium data were found to conform best to Langmuir isotherm model with a theoretical maximum adsorption capacity of 5.4 mg g−1 at 25 °C. The results clearly suggested that the novel avocado-derived can potentially mitigate ammonium from aqueous systems. DA - 2016/12// PY - 2016/12// DO - 10.1016/J.INDCROP.2016.07.016 VL - 92 SP - 34-41 J2 - Industrial Crops and Products LA - en OP - SN - 0926-6690 UR - http://dx.doi.org/10.1016/J.INDCROP.2016.07.016 DB - Crossref KW - Ammonium adsorption KW - Equilibrium isotherm KW - Adsorption kinetics KW - Wastewater treatment KW - SEM KW - Methanesulfonic acid ER - TY - JOUR TI - Transpired solar wall for tempering air in a swine nursery in a humid subtropical climate AU - Shah, Sanjay AU - Marshall, T.K. AU - Matthis, S. T2 - Applied Engineering in Agriculture AB - Abstract. Propane use in livestock barns can be reduced by tempering the incoming fresh air with the transpired solar wall (TSW). A TSW [40.9 m2 (440 ft2) suction velocity of 0.049 m s-1 or (9.64 ft min-1)] that tempered DA - 2016/// PY - 2016/// DO - 10.13031/aea.32.11098 VL - 32 SP - 115–123 ER - TY - JOUR TI - Numerical and experimental investigation of hydrodynamics and light transfer in open raceway ponds at various algal cell concentrations and medium depths AU - Amini, Hossein AU - Hashemisohi, Abolhasan AU - Wang, Lijun AU - Shahbazi, Abolghasem AU - Bikdash, Marwan AU - Dukka, K. C. AU - Yuan, Wenqiao T2 - CHEMICAL ENGINEERING SCIENCE AB - A spectral radiation-transport model was integrated with a three dimensional computational fluid dynamics model to simulate the hydrodynamics and light transfer in open raceway ponds (ORPs). The predicted three-dimensional velocity and light intensity agreed well with measured values collected on a lab-scale ORP. However, there was a slight difference in the predicted velocity profiles using two different types of boundaries for the paddlewheel, i.e., the moving zone boundary and inlet velocity boundary, with R2 values between the predicted and measured velocities of 0.9947 and 0.9838, respectively. The R2 value between the predicted and measured light intensity was 0.9939. Simulations were further conducted on a large-scale ORP with 100 m2 surface area operated at total medium depths of 0.2 and 0.3 m, average cell concentration of 0.4 g/L, and inlet velocities of 0.1, 0.2 and 0.3 m/s from the paddlewheel. The increase of inlet flow velocity from 0.1 to 0.2 m/s resulted in a more uniform cell concentration profile. However, when the inlet velocity was further increased from 0.2 to 0.3 m/s, there was only a slight increase in the uniformity of the cell concentration. In addition, the simulation results showed that sedimentation of cells more likely occurred at the bottom of the ORP with a total medium depth of 0.2 m than at 0.3 m at the same inlet velocity. The increase of inlet velocity from the paddlewheel resulted in a uniformly distributed light intensity in the region near the medium surface (e.g., 0.05 m depth from the surface) owing to improved mixing. However, owing to a sudden drop in the light intensity after a few centimeters from the medium surface, the cell sedimentation that occurred at the bottom of the ORPs had negligible effects on the light penetration depth in the medium. DA - 2016/12/15/ PY - 2016/12/15/ DO - 10.1016/j.ces.2016.09.003 VL - 156 SP - 11-23 SN - 1873-4405 KW - Open raceway pond KW - Microalgae KW - Light intensity distribution KW - Computational fluid dynamics KW - Chlorella vulgaris ER - TY - JOUR TI - Investigation of adsorption of p-cresol on coconut shell-derived activated carbon AU - Zhu, Yiying AU - Kolar, Praveen T2 - JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS AB - Mitigation of odorous volatile organic compounds, such as p-cresol from wastewater needs simple and practical technologies such as adsorption. In this research, an NaOH-activated carbon was prepared from coconut shell (CSAC-SH). Characterization of CSAC-SH suggested that the adsorbent possessed a well-developed microporous/mesoporous structure. To evaluate the performance of CSAC-SH, a series of batch experiments were conducted to investigate the effects of contact time (0–24 h), initial concentration (50–1000 mg L−1) and adsorbent dosage (1–20 mg L−1) on adsorption of p-cresol. The equilibrium data were found to conform to Redlich–Peterson, Fritz–Schluender, and Langmuir isotherms. The maximum monolayer adsorption capacity of 256.9 mg g−1 (298 K) suggested that the prepared adsorbent has a high affinity toward p-cresol. A second-order kinetic model best described the experimental data and adsorption was governed by intraparticle diffusion. The thermodynamic analysis suggested that the adsorption was feasible, spontaneous, and exothermic (298–328 K). Furthermore, a desorption study suggested that chemisorption was dominant in the adsorption process. Results indicate that sodium hydroxide-activated carbon is effective in mitigating p-cresol from wastewater. DA - 2016/11// PY - 2016/11// DO - 10.1016/j.jtice.2016.07.044 VL - 68 SP - 138-146 SN - 1876-1089 KW - p-Cresol KW - Adsorption KW - Activated carbon KW - Physiochemical activation KW - Sodium hydroxide ER - TY - JOUR TI - Eggshell as an inexpensive adsorbent for removal of p-Cresol AU - Wakchaure, G. C. AU - Das, L. AU - Kolar, P. T2 - Transactions of the ASABE DA - 2016/// PY - 2016/// VL - 59 IS - 3 SP - 965-974 ER - TY - JOUR TI - Effect of high-pressure processing of bovine colostrum on immunoglobulin G concentration, pathogens, viscosity, and transfer of passive immunity to calves AU - Foster, Derek M. AU - Poulsen, Keith P. AU - Sylvester, Hannah J. AU - Jacob, Megan E. AU - Casulli, Kaitlyn E. AU - Farkas, Brian E. T2 - JOURNAL OF DAIRY SCIENCE AB - This study aimed to determine the effects of high-pressure processing on the immunoglobulin concentration, microbial load, viscosity, and transfer of passive immunity to calves when applied to bovine colostrum as an alternative to thermal pasteurization. A pilot study using Staphylococcus aureus was conducted to determine which pressure-time treatments are most appropriate for use with bovine colostrum, with the goals of maximizing bacterial inactivation while minimizing IgG content and viscosity changes. Following the pilot study, an inoculation study was conducted in which first-milking colostrum samples from Holstein-Friesian cows were inoculated with known concentrations of various bacteria or viruses and pressure processed at either 300 MPa for up to 60min or at 400MPa for up to 30min. The recovery of total native aerobic bacteria, Escherichia coli, Salmonella enterica ssp. enterica serovar Dublin, Mycobacterium avium ssp. paratuberculosis, bovine herpesvirus type 1, and feline calicivirus were determined after processing. Colostrum IgG content was measured before and after pressure processing. Shear stress and viscosity for each treatment was determined over shear rates encompassing those found during calf feeding and at normal bovine body temperature (37.8°C). Following a calf trial, serum IgG concentration was measured in 14 calves fed 4 L of colostrum pressure processed at 400MPa for 15min. In the pilot study, S. aureus was effectively reduced with pressure treatment at 300 and 400MPa (0, 5, 10, 15, 30, and 45min), with 2 treatments at 400MPa (30, 45min) determined to be inappropriate for use with bovine colostrum due to viscosity and IgG changes. High-pressure processing at 300MPa (30, 45, and 60min) and 400MPa (10, 15, and 20min) was shown to effectively reduce total native aerobic bacteria, E. coli, Salmonella Dublin, bovine herpesvirus type 1, and feline calicivirus populations in bovine colostrum, but no decrease occurred in Mycobacterium avium ssp. paratuberculosis. All inoculation study pressure treatments insignificantly decreased IgG content of colostrum. Treatment of colostrum at 400MPa for 15min during the calf trial decreased IgG content of colostrum. Treatment at 400MPa for 15min increased colostrum viscosity, with 2 of 14 samples requiring dilution with water for calf feeding. Calves fed pressure-processed colostrum had similar serum IgG but lower efficiency of absorption than calves fed heat-treated colostrum. The results of this study suggest that high-pressure processing of bovine colostrum maintains an acceptable IgG level while decreasing bacterial and viral counts. Changes in viscosity sometimes made calf feeding more difficult, but still feasible. Additional research to optimize this technology for on-farm use is necessary. DA - 2016/11// PY - 2016/11// DO - 10.3168/jds.2016-11204 VL - 99 IS - 11 SP - 8575-8588 SN - 1525-3198 KW - high-pressure processing KW - bovine colostrum KW - pasteurization KW - Mycobacterium avium ssp paratuberculosis ER - TY - JOUR TI - Characterization of biochar from rice hulls and wood chips produced in a top-lit updraft biomass gasifier AU - James, R. A. M. AU - Yuan, W. Q. AU - Boyette, M. D. AU - Wang, D. H. AU - Kumar, A. T2 - Transactions of the ASABE DA - 2016/// PY - 2016/// VL - 59 IS - 3 SP - 749-756 ER - TY - JOUR TI - Seasonal Variability in Stormwater Quality Treatment of Permeable Pavements Situated Over Heavy Clay and in a Cold Climate AU - Winston, Ryan J. AU - Davidson-Bennett, Keely M. AU - Buccier, Kristen M. AU - Hunt, William F. T2 - WATER AIR AND SOIL POLLUTION DA - 2016/5// PY - 2016/5// DO - 10.1007/s11270-016-2839-6 VL - 227 IS - 5 SP - SN - 1573-2932 KW - Permeable interlocking concrete pavement KW - Permeable pavement KW - Pervious pavement KW - Internal water storage KW - Road salt KW - Nutrients KW - Sediment KW - Heavy metals ER - TY - JOUR TI - In-situ falling-head test for hydraulic conductivity: Evaluation in layered sediments of an analysis derived for homogenous sediments AU - Burnette, Matthew C. AU - Genereux, David P. AU - Birgand, François T2 - Journal of Hydrology AB - The hydraulic conductivity (K) of streambeds is a critical variable controlling interaction of groundwater and surface water. The Hvorslev analysis for estimating K from falling-head test data has been widely used since the 1950s, but its performance in layered sandy sediments common in streams and lakes has not previously been examined. Our numerical simulations and laboratory experiments show that the Hvorslev analysis yields accurate K values in both homogenous sediment (for which the analysis was originally derived) and layered deposits with low-K sand over high-K sand. K from the Hvorslev analysis deviated significantly from true K only when two conditions were present together: (1) high-K sand was present over low-K sand, and (2) the bottom of the permeameter in which K was measured was at or very near the interface between high-K and low-K. When this combination of conditions exists, simulation and laboratory sand tank results show that in-situ Hvorslev K underestimates the true K of the sediment within a permeameter, because the falling-head test is affected by low-K sediment outside of (below the bottom of) the permeameter. In simulation results, the maximum underestimation (occurring when the bottom of the permeameter was at the interface of high K over low K) was by a factor of 0.91, 0.59, and 0.12 when the high-K to low-K ratio was 2, 10, and 100, respectively. In laboratory sand tank experiments, the underestimation was by a factor of about 0.83 when the high-K to low-K ratio was 2.3. Also, this underestimation of K by the Hvorslev analysis was about the same whether the underlying low-K layer was 2 cm or 174 cm thick (1% or 87% of the domain thickness). Numerical model simulations were useful in the interpretation of in-situ field K profiles at streambed sites with layering; specifically, scaling the model results to the maximum measured K at the top of the field K profiles helped constrain the likely ratio of high K to low K at field locations with layered heterogeneity. Vertical K values are important in field studies of groundwater–surface water interaction, and the Hvorslev analysis can be a useful tool, even in layered media, when applied carefully. DA - 2016/8// PY - 2016/8// DO - 10.1016/j.jhydrol.2016.05.030 VL - 539 SP - 319-329 J2 - Journal of Hydrology LA - en OP - SN - 0022-1694 UR - http://dx.doi.org/10.1016/j.jhydrol.2016.05.030 DB - Crossref KW - Hydraulic conductivity KW - Permeameter KW - Sediments KW - Streambed KW - Numerical modeling KW - Groundwater-surface water interaction ER - TY - JOUR TI - Effects of selenium on biological and physiological properties of the duckweed Landoltia punctata AU - Zhong, Y. AU - Cheng, J. J. T2 - PLANT BIOLOGY AB - Duckweed can be used for bioremediation of selenium (Se) polluted water because of its capability of absorbing minerals from growing media. However, the presence of Se in the media may affect the growth of the duckweed. Landoltia punctata 7449 has been studied for its changes in chemical and biological properties with the presence of Se in the media. The duckweed was cultivated over a 12-day period at different initial concentrations of selenite (Na2 SeO3 ) from 0 to 80 μmol·l(-1) . The growth rate, the organic and total Se contents, the activity of antioxidant enzymes, the photosynthetic pigment contents, the chlorophyll a fluorescence OJIP transient, and the ultrastructure of the duckweed were monitored during the experiment. The results have shown that Se at low concentrations of ≤20 μmol·l(-1) promoted the growth of the L. punctata and inhibited lipid peroxidation. Substantial increases in duckweed growth rate and organic Se content in the duckweed were observed at low Se concentrations. The anti-oxidative effect occurred likely with the increases in guaiacol peroxidase, catalase and superoxide dismutase activities as well as the amount of photosynthetic pigments. However, negative impact to the duckweed was observed when the L. punctata was exposed to high Se concentrations (≥40 μmol·l(-1) ), in which the duckweed growth was inhibited by the selenium. The results indicate that L. punctata 7449 can be used for bioremediation of selenium (Se) polluted water when the Se concentration is ≤20 μmol·l(-1) . DA - 2016/9// PY - 2016/9// DO - 10.1111/plb.12479 VL - 18 IS - 5 SP - 797-804 SN - 1438-8677 KW - Antioxidant enzymes KW - Landoltia punctata KW - photosynthetic pigments KW - selenium ER - TY - JOUR TI - The Effect of Biomass Physical Properties on Top-Lit Updraft Gasification ofWoodchips AU - James R., Arthur M. AU - Yuan, Wenqiao AU - Boyette, Michael D. T2 - ENERGIES AB - The performance of a top-lit updraft gasifier affected by biomass (pine wood) particle size, moisture content and compactness was studied in terms of the biochar yield, biomass burning rate, syngas composition and tar content. The highest biochar yield increase (from 12.2% to 21.8%) was achieved by varying the particle size from 7 to 30 mm, however, larger particles triggered tar generation that reached its maximum of 93.5 g/m3 syngas at 30-mm biomass particles; in contrast, the hydrogen content in syngas was at its minimum of 2.89% at this condition. The increase in moisture content from 10% to 22% reduced biochar yield from 12% to 9.9%. It also reduced the tar content from 12.9 to 6.2 g/m3 which was found to be the lowest range of tar content in this work. Similarly, the carbon monoxide composition in syngas decreased to its minimum of 11.16% at moisture content of 22%. Finally, the biomass compactness increased biochar yield up to 17% when the packing mass was 3 kg. However, the addition of compactness also increased the tar content in syngas, but little effect was noticed in syngas composition. DA - 2016/4// PY - 2016/4// DO - 10.3390/en9040283 VL - 9 IS - 4 SP - SN - 1996-1073 KW - top-lit updraft KW - biochar KW - syngas KW - biomass KW - gasification KW - tar ER - TY - JOUR TI - Role of Conservation Adoption Premiums on Participation in Water Quality Trading Programs AU - Motallebi, Marzieh AU - O'Connell, Caela AU - Hoag, Dana L. AU - Osmond, Deanna L. T2 - WATER AB - Over half of lakes, reservoirs, and ponds in the United States are threatened or impaired, mostly by nutrients. One policy to improve water quality is water quality trading (WQT). While the concept is appealing, adoption of conservation practices in these programs has been anemic at best. Using a case study in the newly-formed WQT market in Jordan Lake, North Carolina, we propose that part of the problem is a large adoption premium (AP) for this program. AP is the amount that farmers require over and above direct adoption costs to participate. In this study, farmers were asked at in-person interviews about their willingness to accept (WTA) a payment to adopt a particular conservation practice (riparian buffers) in order to generate and sell credits. We compared farmers’ WTA to their direct cost of participation, which allowed us to estimate an AP. On average, the AP more than doubles the cost of purchasing credits. The AP sums all of the known indirect costs already cited in the literature, and more, into a single value and is relatively simple to estimate. Knowing the AP would improve the ability of policy makers to accurately estimate what is needed to boost adoption rates in WQT programs and other conservation programs as well. DA - 2016/6// PY - 2016/6// DO - 10.3390/w8060245 VL - 8 IS - 6 SP - SN - 2073-4441 KW - water quality trading KW - conservation practices KW - wedges KW - adoption premium KW - farmer decision-making KW - Jordan Lake ER - TY - JOUR TI - Identifying watershed, landscape, and engineering design factors that influence the biotic condition of restored streams AU - Doll, B. AU - Jennings, G. AU - Spooner, J. AU - Penrose, D. AU - Usset, J. AU - Blackwell, J. AU - Fernandez, M. T2 - Water AB - Restored stream reaches at 79 sites across North Carolina were sampled for aquatic macroinvertebrates using a rapid bioassessment protocol. Morphological design parameters and geographic factors, including watershed and landscape parameters (e.g., valley slope, substrate), were also compiled for these streams. Principal component regression analyses revealed correlations between design and landscape variables with macroinvertebrate metrics. The correlations were strengthened by adding watershed variables. Ridge regression was used to find the best-fit model for predicting dominant taxa from the “pollution sensitive” orders of Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies), or EPT taxa, resulting in coefficient weights that were most interpretable relative to site selection and design parameters. Results indicate that larger (wider) streams located in the mountains and foothills where there are steeper valleys, larger substrate, and undeveloped watersheds are expected to have higher numbers of dominant EPT taxa. In addition, EPT taxa numbers are positively correlated with accessible floodplain width and negatively correlated with width-to-depth ratio and sinuosity. This study indicates that both site selection and design should be carefully considered in order to maximize the resulting biotic condition and associated potential ecological uplift of the stream. DA - 2016/// PY - 2016/// DO - 10.3390/w8040151 VL - 8 IS - 4 KW - rivers/streams KW - restoration KW - macroinvertebrates KW - watersheds ER - TY - JOUR TI - Can rapid assessments predict the biotic condition of restored streams? AU - Doll, B. AU - Jennings, G. AU - Spooner, J. AU - Penrose, D. AU - Usset, J. AU - Blackwell, J. AU - Fernandez, M. T2 - Water AB - Five rapid visual stream assessment methods were applied to 65 restored streams in North Carolina, and the results were correlated with measured macroinvertebrate community metrics to evaluate predictive ability. The USEPA Rapid Bioassessment Protocol (RBP), USDA Stream Visual Assessment Protocol (SVAP), Peterson’s Riparian Channel and Environmental Inventory (RCE), NCSU Eco-Geomorphological Assessment (EGA), and NCSU Stream Performance Assessment (SPA) were applied by teams with expertise in hydrology, fluvial geomorphology, and aquatic ecology. Predictions of most macroinvertebrate metrics were improved by re-weighting assessment variables using principal component analysis (PCA) and including watershed factors (e.g., size, slope, land use). The correlations of EGA, RCE, SPA and SVAP assessment results to macroinvertebrate metrics were most improved by variable re-weighting using PCA, while the correlations of RBP were most improved by adding watershed parameters. Akaike’s Information Criterion (AIC) indicates that PCA re-weighting including watershed parameters improves the predictor model for the total number of dominant EPT taxa more than using the sum total raw points for all five assessment methods. To demonstrate the application of the study results, a single-value index was generated for the RBP method using principal component regression (PCR) based on the EPT (Ephemeroptera, Plecoptera and Trichoptera) taxa metric. DA - 2016/// PY - 2016/// DO - 10.3390/w8040143 VL - 8 IS - 4 KW - rivers/streams KW - restoration KW - rapid habitat assessment KW - macroinvertebrates KW - watersheds ER - TY - JOUR TI - Biomechanical evaluation of adjunctive cerclage wire fixation for the prevention of periprosthetic femur fractures using cementless press-fit total hip replacement AU - Christopher, Scott A. AU - Kim, Stanley E. AU - Roe, Simon AU - Pozzi, Antonio T2 - VETERINARY JOURNAL AB - Periprosthetic femoral fractures are a common complication associated with cementless press-fit total hip arthroplasty. The use of prophylactic cerclage wire fixation has been advocated to reduce this complication. The objective of this study was to evaluate whether a double loop cerclage wire, used as adjunctive fixation, increased the peak torsional load to failure in femora implanted with press-fit cementless stems. Peak torsional load to failure was compared between femora without adjunctive fixation and femora receiving a 1 mm double loop cerclage wire placed proximally to the lesser trochanter. Femora treated with adjunctive cerclage wire fixation failed at 20% greater peak torque (P = 0.0001). In conclusion, a double loop cerclage wire may aid in the prevention of periprosthetic fractures associated with press-fit cementless femoral stems. DA - 2016/8// PY - 2016/8// DO - 10.1016/j.tvjl.2016.04.014 VL - 214 SP - 7-9 SN - 1532-2971 KW - Total hip arthroplasty KW - Cerclage KW - Press fit KW - Periprosthetic fracture ER - TY - JOUR TI - Astaxanthin-Producing Green Microalga Haematococcus pluvialis: From Single Cellto High Value Commercia Products AU - Shah, Md. Mahfuzur R. AU - Liang, Yuanmei AU - Cheng, Jay J. AU - Daroch, Maurycy T2 - FRONTIERS IN PLANT SCIENCE AB - Many species of microalgae have been used as source of nutrient rich food, feed, and health promoting compounds. Among the commercially important microalgae, Haematococcus pluvialis is the richest source of natural astaxanthin which is considered as "super anti-oxidant." Natural astaxanthin produced by H. pluvialis has significantly greater antioxidant capacity than the synthetic one. Astaxanthin has important applications in the nutraceuticals, cosmetics, food, and aquaculture industries. It is now evident that, astaxanthin can significantly reduce free radicals and oxidative stress and help human body maintain a healthy state. With extraordinary potency and increase in demand, astaxanthin is one of the high-value microalgal products of the future.This comprehensive review summarizes the most important aspects of the biology, biochemical composition, biosynthesis, and astaxanthin accumulation in the cells of H. pluvialis and its wide range of applications for humans and animals. In this paper, important and recent developments ranging from cultivation, harvest and postharvest bio-processing technologies to metabolic control and genetic engineering are reviewed in detail, focusing on biomass and astaxanthin production from this biotechnologically important microalga. Simultaneously, critical bottlenecks and major challenges in commercial scale production; current and prospective global market of H. pluvialis derived astaxanthin are also presented in a critical manner. A new biorefinery concept for H. pluvialis has been also suggested to guide toward economically sustainable approach for microalgae cultivation and processing. This report could serve as a useful guide to present current status of knowledge in the field and highlight key areas for future development of H. pluvialis astaxanthin technology and its large scale commercial implementation. DA - 2016/4/28/ PY - 2016/4/28/ DO - 10.3389/fpls.2016.00531 VL - 7 SP - SN - 1664-462X KW - Haematoccoccus pluvialis KW - astaxanthin KW - nutraceuticals KW - algae cultivation and processing KW - biorefinery ER - TY - JOUR TI - The influence of biochar addition on chicken manure composting and associated methane and carbon dioxide emissions AU - Jia, X. Y. AU - Wang, M. AU - Yuan, Wenqiao AU - Ju, X. T. AU - Yang, B. Z. T2 - BioResources AB - The effect of biochar addition and turning frequency was examined relative to biochar-chicken manure co-composting and its associated methane (CH4) and carbon dioxide (CO2) emissions. The results demonstrated that biochar addition was more effective in accelerating the composting process, which was indicated by a 5.2% increase in peak pile temperature and a 148% increase in peak CO2 emission with 20% biochar amended-compost, compared with the control that had no biochar. The compost pH increased and moisture content decreased significantly over the whole course of composting with the biochar amendment. The addition of 20% biochar also resulted in a 54.9% decrease in peak CH4 emission compared with the control. More frequent turning (daily vs. every 3 or 7 days) accelerated the composting process and reduced the CH4 emission. DA - 2016/// PY - 2016/// DO - 10.15376/biores.11.2.5255-5264 VL - 11 IS - 2 SP - 5255–5264 ER - TY - JOUR TI - Temperature dynamics of stormwater runoff in Australia and the USA AU - Hathaway, J. M. AU - Winston, R. J. AU - Brown, R. A. AU - Hunt, W. F. AU - McCarthy, D. T. T2 - SCIENCE OF THE TOTAL ENVIRONMENT AB - Thermal pollution of surface waters by urban stormwater runoff is an often overlooked by-product of urbanization. Elevated stream temperatures due to an influx of stormwater runoff can be detrimental to stream biota, in particular for cold water systems. However, few studies have examined temperature trends throughout storm events to determine how these thermal inputs are temporally distributed. In this study, six diverse catchments in two continents are evaluated for thermal dynamics. Summary statistics from the data showed larger catchments have lower maximum runoff temperatures, minimum runoff temperatures, and temperature variability. This reinforces the understanding that subsurface drainage infrastructure in urban catchments acts to moderate runoff temperatures. The catchments were also evaluated for the presence of a thermal first flush using two methodologies. Results showed the lack of a first flush under traditional assessment methodologies across all six catchments, supporting the results from a limited number of studies in literature. However, the time to peak temperature was not always coincident with the time to peak flow, highlighting the variability of thermal load over time. When a new first flush methodology was applied, significant differences in temperature were noted with increasing runoff depth for five of the six sites. This study is the first to identify a runoff temperature first flush, and highlights the need to carefully consider the appropriate methodology for such analyses. DA - 2016/7/15/ PY - 2016/7/15/ DO - 10.1016/j.scitotenv.2016.03.155 VL - 559 SP - 141-150 SN - 1879-1026 KW - First flush KW - Temperature KW - Urban runoff KW - Thermal pollution ER - TY - JOUR TI - Quantifying the fate of agricultural nitrogen in an unconfined aquifer: Stream-based observations at three measurement scales AU - Gilmore, Troy E. AU - Genereux, David P. AU - Solomon, D. Kip AU - Solder, John E. AU - Kimball, Briant A. AU - Mitasova, Helena AU - Birgand, François T2 - Water Resources Research AB - Abstract We compared three stream‐based sampling methods to study the fate of nitrate in groundwater in a coastal plain watershed: point measurements beneath the streambed, seepage blankets (novel seepage‐meter design), and reach mass‐balance. The methods gave similar mean groundwater seepage rates into the stream (0.3–0.6 m/d) during two 3–4 day field campaigns despite an order of magnitude difference in stream discharge between the campaigns. At low flow, estimates of flow‐weighted mean nitrate concentrations in groundwater discharge ([ ] FWM ) and nitrate flux from groundwater to the stream decreased with increasing degree of channel influence and measurement scale, i.e., [ ] FWM was 654, 561, and 451 µ M for point, blanket, and reach mass‐balance sampling, respectively. At high flow the trend was reversed, likely because reach mass‐balance captured inputs from shallow transient high‐nitrate flow paths while point and blanket measurements did not. Point sampling may be better suited to estimating aquifer discharge of nitrate, while reach mass‐balance reflects full nitrate inputs into the channel (which at high flow may be more than aquifer discharge due to transient flow paths, and at low flow may be less than aquifer discharge due to channel‐based nitrate removal). Modeling dissolved N 2 from streambed samples suggested (1) about half of groundwater nitrate was denitrified prior to discharge from the aquifer, and (2) both extent of denitrification and initial nitrate concentration in groundwater (700–1300 µ M ) were related to land use, suggesting these forms of streambed sampling for groundwater can reveal watershed spatial relations relevant to nitrate contamination and fate in the aquifer. DA - 2016/3// PY - 2016/3// DO - 10.1002/2015wr017599 VL - 52 IS - 3 SP - 1961-1983 J2 - Water Resour. Res. LA - en OP - SN - 0043-1397 UR - http://dx.doi.org/10.1002/2015WR017599 DB - Crossref KW - unconfined aquifer KW - nonpoint source nitrogen KW - groundwater contamination KW - coastal plain KW - denitrification KW - hyphoreic zone ER - TY - JOUR TI - Influence of nitrogen and mepiquat chloride on cotton canopy reflectance measurements AU - Foote, W. AU - Edmisten, K. AU - Wells, R. AU - Collins, G. AU - Roberson, G. AU - Jordan, D. AU - Fisher, L. T2 - Journal of Cotton Science DA - 2016/// PY - 2016/// VL - 20 IS - 1 SP - 1-7 ER - TY - JOUR TI - Expanding Maize Genetic Resources with Predomestication Alleles: Maize–Teosinte Introgression Populations AU - Liu, Zhengbin AU - Cook, Jason AU - Melia‐Hancock, Susan AU - Guill, Katherine AU - Bottoms, Christopher AU - Garcia, Arturo AU - Ott, Oliver AU - Nelson, Rebecca AU - Recker, Jill AU - Balint‐Kurti, Peter AU - Larsson, Sara AU - Lepak, Nicholas AU - Buckler, Ed AU - Trimble, Loren AU - Tracy, William AU - McMullen, Michael D. AU - Flint‐Garcia, Sherry A. T2 - The Plant Genome AB - Teosinte ( subsp. H. H. Iltis & Doebley) has greater genetic diversity than maize inbreds and landraces ( subsp. ). There are, however, limited genetic resources to efficiently evaluate and tap this diversity. To broaden resources for genetic diversity studies in maize, we developed and evaluated 928 near-isogenic introgression lines (NILs) from 10 teosinte accessions in the B73 background. Joint linkage analysis of the 10 introgression populations identified several large-effect quantitative trait loci (QTL) for days to anthesis (DTA), kernel row number (KRN), and 50-kernel weight (Wt50k). Our results confirm prior reports of kernel domestication loci and identify previously uncharacterized QTL with a range of allelic effects enabling future research into the genetic basis of these traits. Additionally, we used a targeted set of NILs to validate the effects of a KRN QTL located on chromosome 2. These introgression populations offer novel tools for QTL discovery and validation as well as a platform for initiating fine mapping. DA - 2016/3// PY - 2016/3// DO - 10.3835/plantgenome2015.07.0053 VL - 9 IS - 1 SP - J2 - The Plant Genome LA - en OP - SN - 1940-3372 1940-3372 UR - http://dx.doi.org/10.3835/plantgenome2015.07.0053 DB - Crossref ER - TY - JOUR TI - Determination of Biosolids Phosphorus Solubility and Its Relationship to Wastewater Treatment AU - Jameson, Molly AU - White, Jeffrey G. AU - Osmond, Deanna L. AU - Aziz, Tarek T2 - WATER ENVIRONMENT RESEARCH AB - ABSTRACT: In North Carolina (NC), biosolids land application rates governed by crop nitrogen (N) requirements typically surpass crop phosphorus (P) needs, increasing surface water pollution potential. The NC Department of Environmental Quality (NCDEQ) is considering P‐based biosolids application guidelines for some nutrient‐impaired watersheds using the P Loss Assessment Tool (PLAT), but important biosolids information is lacking: total P (TP), water‐extractable P (WEP), and percent water‐extractable P (PWEP). In each of three seasons, we sampled 28 biosolids from 26 participating water resource recovery facilities (WRRFs) and analyzed for TP, WEP, and percent dry matter (DM), from which PWEP and nonsoluble P were calculated. Based on descriptive statistics and an online survey of treatment processes, biosolids were divided into Class A‐alkaline, Class A‐heat, Class B‐slurry, and Class B‐cake. The average TP in Class A alkaline stabilized biosolids was more than five times less than the average of the other biosolids, 5.0 vs. 26.6 g/kg, respectively. Averaged over biosolids, WEP and PWEP were 1.4 g/kg and 5.0%, respectively. Stabilization processes appeared to reduce WEP substantially, so biosolids potential soluble‐P loss is low. Our data will allow PLAT to be used for biosolids P‐loss risk assessments. DA - 2016/7/1/ PY - 2016/7/1/ DO - 10.2175/106143016x14609975746406 VL - 88 IS - 7 SP - 602-610 SN - 1554-7531 KW - biosolids KW - phosphorus content KW - water extractable phosphorus KW - land application KW - stabilization processes KW - wastewater ER - TY - JOUR TI - The Effect of Light Stress and Other Culture Conditions on Photoinhibition and Growth of Dunaliella tertiolecta AU - Seepratoomrosh, Jitpisut AU - Pokethitiyook, Prayad AU - Meetam, Metha AU - Yokthongwattana, Kittisak AU - Yuan, Wenqiao AU - Pugkaew, Wanvisa AU - Kangvansaichol, Kunn T2 - APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY DA - 2016/1// PY - 2016/1// DO - 10.1007/s12010-015-1882-x VL - 178 IS - 2 SP - 396-407 SN - 1559-0291 KW - Light stress KW - Photoinhibition KW - Pre-acclimation KW - Dunaliella tertiolecta KW - Biofuel KW - Microalgae ER - TY - JOUR TI - Runoff and Pollutant Export from a LID Subdivision in North Carolina AU - Line, D. E. AU - White, N. M. T2 - JOURNAL OF ENVIRONMENTAL ENGINEERING AB - Storm rainfall on and runoff from a 3.35-ha low-impact development (LID) residential subdivision in the Piedmont region of North Carolina were monitored for 6+ years, which included predevelopment, during-development, and postdevelopment phases. Runoff was monitored and sampled at two stations using automated samplers. Along with residences, the drainage area to one of the stations (PC1) included an undisturbed wooded riparian buffer with level spreaders to distribute runoff, while the area to the other station (PC2) included four bioretention areas, permeable pavement, a roof runoff collection system, a detention pond, and other LID measures. Monitoring results documented that the postdevelopment, runoff to rainfall ratio, and pollutant export at both stations were significantly greater than those of the predevelopment phase, during which time the land use on the site was mature woods. The total nitrogen (TN), total phosphorus (TP), and total suspended solids (TSS) export at both LID monitoring stations was 23 to 92% less than those from a nearby conventionally-developed subdivision monitored previously. These data indicated that LID subdivisions constructed on moderately to slowly permeable soils may not be able to maintain the runoff to rainfall ratio and TN, TP, and TSS export if the predevelopment land use was mature woods; however, if the predevelopment land use was cropland mixed with woods, then it may be possible to maintain predevelopment runoff to rainfall ratio and TN, TP, and TSS export. Further, the extensive use of LID techniques/measures in this residential subdivision resulted in less TN, TP, and TSS export compared to a similar conventional subdivision. DA - 2016/1// PY - 2016/1// DO - 10.1061/(asce)ee.1943-7870.0001018 VL - 142 IS - 1 SP - SN - 1943-7870 ER - TY - JOUR TI - Quantifying volume reduction and peak flow mitigation for three bioretention cells in clay soils in northeast Ohio AU - Winston, Ryan J. AU - Dorsey, Jay D. AU - Hunt, William F. T2 - SCIENCE OF THE TOTAL ENVIRONMENT AB - Green infrastructure aims to restore watershed hydrologic function by more closely mimicking pre-development groundwater recharge and evapotranspiration (ET). Bioretention has become a popular stormwater control due to its ability to reduce runoff volume through these pathways. Three bioretention cells constructed in low permeability soils in northeast Ohio were monitored for non-winter quantification of inflow, drainage, ET, and exfiltration. The inclusion of an internal water storage (IWS) zone allowed the three cells to reduce runoff by 59%, 42%, and 36% over the monitoring period, in spite of the tight underlying soils. The exfiltration rate and the IWS zone thickness were the primary determinants of volume reduction performance. Post-construction measured drawdown rates were higher than pre-construction soil vertical hydraulic conductivity tests in all cases, due to lateral exfiltration from the IWS zones and ET, which are not typically accounted for in pre-construction soil testing. The minimum rainfall depths required to produce outflow for the three cells were 5.5, 7.4, and 13.8mm. During events with 1-year design rainfall intensities, peak flow reduction varied from 24 to 96%, with the best mitigation during events where peak rainfall rate occurred before the centroid of the rainfall volume, when adequate bowl storage was available to limit overflow. DA - 2016/5/15/ PY - 2016/5/15/ DO - 10.1016/j.scitotenv.2016.02.081 VL - 553 SP - 83-95 SN - 1879-1026 KW - Biohlter KW - Exfilrration KW - Internal water storage KW - Hydrology KW - Hydraulics KW - Flow duration ER - TY - JOUR TI - Maize Homologs of CCoAOMT and HCT, Two Key Enzymes in Lignin Biosynthesis, Form Complexes with the NLR Rp1 Protein to Modulate the Defense Response AU - Wang, Guan-Feng AU - Balint-Kurti, Peter J. T2 - Plant Physiology AB - Disease resistance (R) genes encode nucleotide binding Leu-rich-repeat (NLR) proteins that confer resistance to specific pathogens. Upon pathogen recognition they trigger a defense response that usually includes a so-called hypersensitive response (HR), a rapid localized cell death at the site of pathogen infection. Intragenic recombination between two maize (Zea mays) NLRs, Rp1-D and Rp1-dp2, resulted in the formation of a hybrid NLR, Rp1-D21, which confers an autoactive HR in the absence of pathogen infection. From a previous quantitative trait loci and genome-wide association study, we identified genes encoding two key enzymes in lignin biosynthesis, hydroxycinnamoyltransferase (HCT) and caffeoyl CoA O-methyltransferase (CCoAOMT), adjacent to the nucleotide polymorphisms that were highly associated with variation in the severity of Rp1-D21-induced HR We have previously shown that the two maize HCT homologs suppress the HR conferred by Rp1-D21 in a heterologous system, very likely through physical interaction. Here, we show, similarly, that CCoAOMT2 suppresses the HR induced by either the full-length or by the N-terminal coiled-coil domain of Rp1-D21 also likely via physical interaction and that the metabolic activity of CCoAOMT2 is unlikely to be necessary for its role in suppressing HR. We also demonstrate that CCoAOMT2, HCTs, and Rp1 proteins can form in the same complexes. A model is derived to explain the roles of CCoAOMT and HCT in Rp1-mediated defense resistance. DA - 2016/5/10/ PY - 2016/5/10/ DO - 10.1104/pp.16.00224 VL - 171 IS - 3 SP - 2166-2177 J2 - Plant Physiol. LA - en OP - SN - 0032-0889 1532-2548 UR - http://dx.doi.org/10.1104/pp.16.00224 DB - Crossref ER - TY - JOUR TI - Driving forces of effluent nutrient variability in field scale bioretention AU - Manka, B. N. AU - Hathaway, J. M. AU - Tirpak, R. A. AU - He, Q. AU - Hunt, W. F. T2 - ECOLOGICAL ENGINEERING AB - Nutrient exports from urbanized watersheds have been identified as a major contributor to surface water degradation worldwide. As efforts to implement stormwater treatment controls, such as bioretention, become increasingly common, understanding how the functionality of these systems varies based on environmental conditions is critical. Quantifying this variability and its causes will aid in developing more robust models and watershed restoration plans which incorporate the uncertainty of bioretention function. This study investigated effluent nutrient concentrations from ten bioretention areas in North Carolina, USA. Nitrogen species were found to have higher variability than phosphorus species, with changes in effluent concentrations being significantly influenced by environmental conditions. In particular, effluent concentrations of total nitrogen (TN) and nitrate (NO3-N) were strongly correlated to antecedent rainfall depth and temperature. As antecedent rainfall depth increased, NO3-N and TN concentrations decreased. These trends have been noted in other laboratory-based studies and are logical based on the influence of dry conditions on microbial communities. Increases in ambient temperature were shown to increase effluent TN and NO3-N concentrations in conventionally drained systems. However, a negative correlation was found between temperature and effluent NO3-N concentrations in systems with an internal water storage (IWS) layer, suggesting increased denitrifying microbe activity. These results show that variability in effluent nutrient concentrations can be explained by environmental conditions, and that the effects of these conditions may differ based on system design. DA - 2016/9// PY - 2016/9// DO - 10.1016/j.ecoleng.2016.06.024 VL - 94 SP - 622-628 SN - 1872-6992 KW - Bioretention KW - Climate KW - Variability KW - Nutrients KW - Temperature KW - Rainfall ER - TY - JOUR TI - Development/ripening of ecosystems services in the first two growing seasons of a regional-scale constructed stormwater wetland on the coast of North Carolina AU - Merriman, L. S. AU - Hunt, W. F. AU - Bass, K. L. T2 - ECOLOGICAL ENGINEERING AB - A well-functioning constructed stormwater wetland (CSW) will provide many ecosystem services. However, there has not been an effort to monitor and evaluate these services as a CSW develops in the first years after construction – the ‘ripening’ period. In this study, ecosystem services development was assessed during the first two growing seasons of a CSW located on the coast of North Carolina. The CSW research site was a regional-scale stormwater project with two different flow regimes: event and base flow. The full potential of some ecosystem services of this CSW were realized immediately such as volume reduction, TSS and NO2,3 treatment. Others were fully developed after the 1st growing season, e.g. TAN, ON, TN, and TP treatment. Mostly, ripening of the CSW was complete, as areal C densities exceeded median C densities observed in other stormwater wetlands, and vegetation biodiversity measurements aligned with other stormwater wetlands in North Carolina, just one year after construction. The establishment of vegetation was deemed the most important design goal during this vital period, as vegetation is interlinked with other services: evapotranspiration, water quality improvement, and C input to the soil. DA - 2016/9// PY - 2016/9// DO - 10.1016/j.ecoleng.2016.05.065 VL - 94 SP - 393-405 SN - 1872-6992 KW - Ecosystem services KW - Stormwater management KW - Constructed stormwater wetlands KW - Carbon sequestration KW - Biodiversity KW - Water quality ER - TY - JOUR TI - A Genome-Wide Association Study for Partial Resistance to Maize Common Rust AU - Olukolu, Bode A. AU - Tracy, William F. AU - Wisser, Randall AU - De Vries, Brian AU - Balint-Kurti, Peter J. T2 - PHYTOPATHOLOGY AB - Quantitative resistance to maize common rust (causal agent Puccinia sorghi) was assessed in an association mapping population of 274 diverse inbred lines. Resistance to common rust was found to be moderately correlated with resistance to three other diseases and with the severity of the hypersensitive defense response previously assessed in the same population. Using a mixed linear model accounting for the confounding effects of population structure and flowering time, genome-wide association tests were performed based at 246,497 single-nucleotide polymorphism loci. Three loci associated with maize common rust resistance were identified. Candidate genes at each locus had predicted roles, mainly in cell wall modification. Other candidate genes included a resistance gene and a gene with a predicted role in regulating accumulation of reactive oxygen species. DA - 2016/7// PY - 2016/7// DO - 10.1094/phyto-11-15-0305-r VL - 106 IS - 7 SP - 745-751 SN - 1943-7684 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84975087459&partnerID=MN8TOARS KW - association analysis KW - disease resistance KW - linkage disequilibrium KW - QTL ER - TY - JOUR TI - Variability and distribution among sample test results when sampling unprocessed wheat lots for ochratoxin A AU - Whitaker, T. B. AU - Slate, A. B. AU - Nowicki, T. W. AU - Giesbrecht, F. G. T2 - WORLD MYCOTOXIN JOURNAL AB - In 2008, Health Canada announced it was considering the establishment of maximum levels for ochratoxin A (OTA) in unprocessed wheat, oats, and their products. The Canada Grains Council and Canadian National Millers Association initiated two studies to measure the variability and distribution among sample test results for unprocessed wheat and oats so that scientifically based OTA sampling plans could be designed to meet regulatory and industry requirements. Sampling statistics related to detecting OTA in oats has been published. 54 OTA contaminated wheat lots representing three wheat classes were identified for the sampling study. Each lot was sampled according to a nested experimental protocol where sixteen 2-kg laboratory samples were taken from each lot, multiple 5-g test portions were taken from each comminuted 2-kg laboratory sample, and multiple OTA measurements were made on each test portion using liquid chromatography. The sampling, sample preparation, and analytical variances associated with each step of the OTA test procedure were found to be a function of OTA concentration and regression equations were developed to predict the functional relationships between variance and OTA concentration. When sampling a wheat lot containing 5 µg/kg OTA with an OTA test procedure consisting of a sampling step employing a single 2-kg laboratory sample, sample preparation step employing a single 100-g test portion, and an analytical step that used liquid chromatography to quantify OTA, the sampling step accounted for 95.3% of the total variability. The observed OTA distribution among the 16 OTA sample results was found to be positively skewed and the negative binomial distribution was selected to model the OTA distribution among sample test results. The sampling statistics were incorporated into the FAO Mycotoxin Sampling Tool and the chances of rejecting good lots and accepting bad lots were calculated for various sampling plan designs. DA - 2016/// PY - 2016/// DO - 10.3920/wmj2015.1970 VL - 9 IS - 2 SP - 163-178 SN - 1875-0796 KW - sampling plan KW - maximum level KW - buyer's risk KW - seller's risk KW - OC curve ER - TY - JOUR TI - Size Distributions of Bioaerosols in an Egg Production Facility and Its Vicinity AU - Hu, Di AU - Wang-Li, Lingjuan AU - Simmons, Otto D. AU - Classen, John J. AU - Osborne, Jason A. T2 - ENVIRONMENTAL ENGINEERING SCIENCE AB - Air emissions from animal feeding operations may cause elevated concentrations of bioaerosols in surrounding areas, posing adverse health effects to the people working on or living near the farm. Concentrations of nonselective airborne bacteria and fungi in various size ranges were measured by the Andersen six-stage viable samplers in an egg production house and at four ambient stations surrounding the farm in winter, spring, and summer. It was discovered that in-house bacterial particle size distributions (PSDs) were different among seasons. Under higher temperature and lower relative humidity conditions, more bacteria were associated with the small size ranges. Seasonal variations of in-house fungal PSDs were not significant. On average, 60–80% of in-house bacteria were in respirable size range (≤4.7 μm), whereas 60–70% of in-house fungi were in respirable size range. Bacterial PSDs at ambient locations were different among stations in winter but not in spring and summer. There were significant differences in fungal PSDs among ambient stations in three seasons. On average, 50–80% of ambient bacteria were in respirable size range, and 60–90% of ambient fungi were in respirable range. DA - 2016/4/1/ PY - 2016/4/1/ DO - 10.1089/ees.2015.0220 VL - 33 IS - 4 SP - 215-223 SN - 1557-9018 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84964715430&partnerID=MN8TOARS KW - size distribution KW - animal feeding operation KW - bacteria KW - bioaerosol KW - fungi ER - TY - JOUR TI - Optimization of Cultural Conditions for Antioxidant Exopolysaccharides from Xerocomus badius Grown in Shrimp Byproduct AU - Gao, Xiujun AU - Yan, Peisheng AU - Liu, Xin AU - Wang, Jianbing AU - Yu, Jiajia T2 - BIOMED RESEARCH INTERNATIONAL AB - To optimize the production conditions for exopolysaccharides with higher antioxidant activities from Xerocomus badius cultured in shrimp byproduct medium, Plackett-Burman design, path of steepest ascent, and response surface methodology were explored. Based on the results of Plackett-Burman design and path of steepest ascent, a Box-Behnken design was applied to optimization and the regression models. The optimal cultural condition for high yield and antioxidant activity of the exopolysaccharides was determined to be 10.347% of solid-to-liquid ratio, a 4.322% content of bran powder, and a 1.217% concentration of glacial acetic acid. Culturing with the optimal cultural conditions resulted in an exopolysaccharides yield of 4.588 ± 0.346 g/L and a total antioxidant activity of 2.956 ± 0.105 U/mg. These values are consistent with the values predicted by the corresponding regression models (RSD < 5%). DA - 2016/// PY - 2016/// DO - 10.1155/2016/2043787 VL - 2016 SP - SN - 2314-6141 ER - TY - JOUR TI - Identification of Alleles Conferring Resistance to Gray Leaf Spot in Maize Derived from its Wild Progenitor Species Teosinte AU - Lennon, Jill R. AU - Krakowsky, Matthew AU - Goodman, Major AU - Flint-Garcia, Sherry AU - Balint-Kurti, Peter J. T2 - Crop Science AB - ABSTRACT Gray leaf spot (GLS; causal agent Cercospora zeae‐maydis and Cercospora zeina ) is an important maize ( Zea mays L.) disease in the United States. Current control methods for GLS include using resistant cultivars, crop rotation, chemical applications, and conventional tillage to reduce inoculum levels. Teosinte ( Z. mays subsp. parviglumis ) is the wild progenitor of maize and easily forms hybrids with current maize inbreds. The aims of this study were to identify alleles from teosinte that, when introduced into temperate maize germplasm, conferred significant levels of GLS resistance. A population of 693 BC 4 S 2 near isogenic lines (NILs), developed by crossing nine different teosinte accessions into the background of the maize inbred B73, were evaluated for GLS resistance in replicated field trials over 2 yr. Six markers significantly associated with GLS resistance were identified using 768 single nucleotide polymorphism (SNP) markers used to genotype this population. Twenty‐seven individual NILs that differed significantly from B73 for GLS resistance and that carried teosinte introgressions at the significantly associated SNPs at bins 2.04, 3.06, 4.07, 5.03, 8.06, and 9.03 were selected for follow‐up studies. F 2:3 populations were developed by crossing each selected NIL to B73 followed by self‐pollinating the progeny twice. These F 2:3 populations were evaluated for GLS resistance and genotyped at the loci of interest. In most cases, single‐marker analysis validated predicted allelic substitution effects from the original NIL populations. DA - 2016/1// PY - 2016/1// DO - 10.2135/cropsci2014.07.0468 VL - 56 IS - 1 SP - 209-218 J2 - Crop Science LA - en OP - SN - 0011-183X UR - http://dx.doi.org/10.2135/cropsci2014.07.0468 DB - Crossref ER - TY - JOUR TI - Developments in mycotoxin analysis: an update for 2014-2015 AU - Berthiller, F. AU - Brera, C. AU - Crews, C. AU - Iha, M. H. AU - Krska, R. AU - Lattanzio, V. M. T. AU - MacDonald, S. AU - Malone, R. J. AU - Maragos, C. AU - Solfrizzo, M. AU - Stroka, J. AU - Whitaker, T. B. T2 - WORLD MYCOTOXIN JOURNAL AB - This review summarises developments in the determination of mycotoxins over a period between mid-2014 and mid-2015. In tradition with previous articles of this series, analytical methods to determine aflatoxins, Alternaria toxins, ergot alkaloids, fumonisins, ochratoxins, patulin, trichothecenes and zearalenone are covered in individual sections. Advances in proper sampling strategies are discussed in a dedicated section, as are new methods used to analyse botanicals and spices and newly developed LC-MS based multi-mycotoxin methods. The critical review aims to briefly discuss the most important developments and trends in mycotoxin determination as well as to address shortcomings of current methodologies. DA - 2016/// PY - 2016/// DO - 10.3920/wmj2015.1998 VL - 9 IS - 1 SP - 5-29 SN - 1875-0796 KW - aflatoxin KW - Alternaria toxins KW - ergot alkaloids KW - fumonisin KW - ochratoxin A KW - patulin KW - trichothecene KW - zearalenone KW - sampling KW - multi-mycotoxin KW - botanicals KW - method development ER - TY - JOUR TI - Curve Number and Runoff Coefficients for Extensive Living Roofs AU - Fassman-Beck, Elizabeth AU - Hunt, William AU - Berghage, Robert AU - Carpenter, Donald AU - Kurtz, Timothy AU - Stovin, Virginia AU - Wadzuk, Bridget T2 - Journal of Hydrologic Engineering AB - Living roofs are a green infrastructure (GI)/low-impact development (LID) stormwater control measure (SCM) increasingly drawing worldwide attention. Despite substantial performance evidence in the literature, the lack of a curve number (CN) or volumetric runoff coefficient (Cv) to apply to prescribed methodologies for planning and regulatory submissions may be perceived as a barrier for implementation. Paired rainfall–runoff data were analyzed for up to 21 living roofs with varying configurations and in different climates from studies identified in the literature and previously-unpublished data. Frequency analysis of empirical performance evidence from 14 living roofs indicates that meaningful runoff is not generated from the majority of small rainfall events. Where planning requires the use of the CN method, a step function is suggested: (1) runoff volume=0 for design rainfall events up to 20–30 mm, if appropriate moisture storage capacity is provided by the substrate; (2) runoff volume is determined with CN=84 for larger rainfall events, or for events that exceed the actual moisture storage capacity. Cv increases with rainfall depth (P), and may be reasonably predicted for 16 living roofs by Cv=a*exp(b/P), where regression coefficients a and b were empirically determined for each climate zone. CN or Cv values are considered best fit, but they are generally poor representations of actual living roof hydrology. Further work is required to develop living roof specific, verified continuous simulation computer-modeling techniques and to quantify the role of the plants in stormwater control. DA - 2016/3// PY - 2016/3// DO - 10.1061/(ASCE)HE.1943-5584.0001318 VL - 21 IS - 3 SP - 04015073 J2 - J. Hydrol. Eng. LA - en OP - SN - 1084-0699 1943-5584 UR - http://dx.doi.org/10.1061/(ASCE)HE.1943-5584.0001318 DB - Crossref KW - Living roof KW - Green roof KW - Curve number KW - TR-55 KW - Runoff coefficient KW - Rational formula KW - Stormwater management KW - Low-impact development KW - Green infrastructure ER - TY - JOUR TI - Starch characterization and ethanol production of duckweed and corn kernel AU - Lee, Chang Joo AU - Yangcheng, Hanyu AU - Cheng, Jay J. AU - Jane, Jay-Lin T2 - STARCH-STARKE AB - The objectives of this study were to characterize the chemical structure, physical properties, enzyme digestibility, and ethanol production of duckweed starch and compare them with that of corn starch (B73). Duckweed consisted of 23.3% starch (dry basis, db), which was less than B73 corn kernels (66.5%). The morphology of duckweed starch granules displayed disk/dome shapes with one side of the granule flat and diameters of 4–9 µm. Duckweed starch displayed a B‐type polymorph, having an average amylopectin branch‐chain length of DP 26.5, and 35.7% amylose; both were larger than corn starch counterparts (DP 21.3 and 31.0%, respectively). Cooked duckweed starch showed higher resistant‐starch content (14.1%) and a greater percentage of retrogradation after 7‐day storage (57.5%) than the cooked B73 corn starch counterparts (8.7 and 49.6%, respectively). Duckweed plant produced a smaller ethanol‐yield (12.0 g/100 g plant, db) but a greater ethanol‐conversion efficiency (90.8%) than the B73 corn kernels (33.7 g/100 g kernels and 89.4%, respectively). DA - 2016/4// PY - 2016/4// DO - 10.1002/star.201500126 VL - 68 IS - 3-4 SP - 348-354 SN - 1521-379X KW - Corn starch KW - Duckweed starch KW - Ethanol yield KW - Starch digestibility KW - Starch structure ER - TY - JOUR TI - Roadside soils show low plant available zinc and copper concentrations AU - Morse, Natalie AU - Walter, M. Todd AU - Osmond, Deanna AU - Hunt, William T2 - ENVIRONMENTAL POLLUTION AB - Vehicle combustion and component wear are a major source of metal contamination in the environment, which could be especially concerning where road ditches are actively farmed. The objective of this study was to assess how site variables, namely age, traffic (vehicles day−1), and percent carbon (%C) affect metal accumulation in roadside soils. A soil chronosequence was established with sites ranging from 3 to 37 years old and bioavailable, or mobile, concentrations of Zinc (Zn) and Copper (Cu) were measured along major highways in North Carolina using a Mehlich III extraction. Mobile Zn and Cu concentrations were low overall, and when results were scaled via literature values to “total metal”, the results were still generally lower than previous roadside studies. This could indicate farming on lands near roads would pose a low plant toxicity risk. Zinc and Cu were not correlated with annual average traffic count, but were positively correlated with lifetime traffic load (the product of site age and traffic count). This study shows an often overlooked variable, site age, should be included when considering roadside pollution accumulation. Zinc and Cu were more strongly associated with %C, than traffic load. Because vehicle combustion is also a carbon source, it is not obvious whether the metals and carbon are simply co-accumulating or whether the soil carbon in roadside soils may facilitate previously overlooked roles in sequestering metals on-site. DA - 2016/2// PY - 2016/2// DO - 10.1016/j.envpol.2015.11.011 VL - 209 SP - 30-37 SN - 1873-6424 KW - Highway KW - Zinc KW - Copper KW - Soil pollution KW - Traffic ER - TY - JOUR TI - Multiple modes of water quality impairment by fecal contamination in a rapidly developing coastal area: southwest Brunswick County, North Carolina AU - Cahoon, L. B. AU - Hales, J. C. AU - Carey, E. S. AU - Loucaides, S. AU - Rowland, K. R. AU - Toothman, B. R. T2 - Environmental Monitoring and Assessment DA - 2016/// PY - 2016/// VL - 188 IS - 2 ER - TY - JOUR TI - Evaluating Retention Capacity of Infiltration Rain Gardens and Their Potential Effect on Urban Stormwater Management in the Sub-Humid Loess Region of China AU - Tang, S. AU - Luo, W. AU - Jia, Z. AU - Liu, W. AU - Li, S. AU - Wu, Y. T2 - WATER RESOURCES MANAGEMENT DA - 2016/2// PY - 2016/2// DO - 10.1007/s11269-015-1206-5 VL - 30 IS - 3 SP - 983-1000 SN - 1573-1650 KW - Rain garden KW - Stormrunoff KW - Design storm KW - Infiltration KW - Overflow KW - LID ER - TY - JOUR TI - DRAINMOD-based tools for quantifying reductions in annual drainage flow and nitrate losses resulting from drainage water management on croplands in eastern North Carolina AU - Negm, L. M. AU - Youssef, M. A. AU - Chescheir, G. M. AU - Skaggs, R. W. T2 - AGRICULTURAL WATER MANAGEMENT AB - Nitrogen (N) leachate of drained agriculture has continued to be pervasive in the U.S. water resources. Nitrogen credit exchange program is a trading market to facilitate pollutant reductions and protect the environment. A simple tool suitable for eastern North Carolina (NC) was developed to quantify drainage flow and N mass reductions resulting from drainage water management (DWM); an efficient and common conservation practice for drained agricultural lands. The tool comprises a set of regression equations estimating the performance of DWM as a function of local site conditions. DRAINMOD and DRAINMOD-NII models simulations were conducted for a wide range of soil types, weather conditions, and management practices for different locations in eastern NC. Simulation results were used with SAS 9.3 software to develop a set of multi-linear regression equations to estimate DWM-caused reductions in annual drainage flow and corresponding nitrate-N (NO3-N) losses for continuous corn (CC) and corn–wheat–soybean (CWS) cropping systems. The regression model estimations of annual drainage flow were highly correlated with DRAINMOD simulated values with an adjusted coefficient of multiple determination (R2adj) equal to 0.91 or higher for different management scenarios. Similarly, the regression model estimations of annual nitrate losses achieved an R2adj of 0.88 or higher for all management scenarios. The developed regression models were further compared on a year-by-year basis to the calibrated DRAINMOD and DRAINMOD-NII models for local conditions of an experimental site in eastern NC over 25 years. Estimated annual drainage flow and NO3-N losses were in good agreement with corresponding values simulated by DRAINMOD-based models for CC and CWS under free and controlled drainage modes. In terms of DWM-induced annual reductions in drainage flow and N losses, noticeable differences occurred in several years between predictions of DRAINMOD-NII and the regression models. A comparison based on the 5-year moving average of DWM-induced reductions smoothed out the extreme year-to-year variations and indicated very similar reduction trends provided by both methods. The results presented in this case study indicated that the simple regression method provides an adequate alternative to the processes based DRAINMOD suite of models for estimating annual reductions in drainage rates and N mass losses resulting from implementation of DWM. Similar tools can be developed for other regions in the US and abroad that initiate nitrogen trading markets involving DWM. DA - 2016/3/1/ PY - 2016/3/1/ DO - 10.1016/j.agwat.2015.12.014 VL - 166 SP - 86-100 SN - 1873-2283 KW - DRAINMOD KW - DRAINMOD-NII KW - Regression analysis KW - Agricultural drainage KW - Nitrogen trading KW - Controlled drainage ER - TY - PCOMM TI - Ability of the Tightrope((R)) and Percutaneous Lateral Fabellar Suture Techniques to Control Cranial Tibial Translation AU - Roe, Simon C. AU - Biskup, Jeffrey J. AB - Veterinary SurgeryVolume 45, Issue 1 p. 133-134 Letter to the Editor Ability of the Tightrope® and Percutaneous Lateral Fabellar Suture Techniques to Control Cranial Tibial Translation Simon C. Roe, Simon C. Roe Small Animal Orthopedic Surgery, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NCSearch for more papers by this author Simon C. Roe, Simon C. Roe Small Animal Orthopedic Surgery, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NCSearch for more papers by this author First published: 05 January 2016 https://doi.org/10.1111/vsu.12430Read 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 onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume45, Issue1January 2016Pages 133-134 RelatedInformation DA - 2016/1// PY - 2016/1// DO - 10.1111/vsu.12430 SP - 133-134 ER - TY - JOUR TI - Three-Dimensional Simulation of Ultrasound-Induced Microalgal Cell Disruption AU - Wang, M. AU - Yuan, W. AU - Hale, Andy T2 - APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY DA - 2016/3// PY - 2016/3// DO - 10.1007/s12010-015-1937-z VL - 178 IS - 6 SP - 1184-1195 SN - 1559-0291 KW - Microalgae KW - Ultrasound KW - Cell disruption KW - Cavitation ER - TY - JOUR TI - Maintenance measures for preservation and recovery of permeable pavement surface infiltration rate - The effects of street sweeping, vacuum cleaning, high pressure washing, and milling AU - Winston, R. J. AU - Al-Rubaei, A. M. AU - Blecken, G. T. AU - Viklander, M. AU - Hunt, W. F. T2 - Journal of Environmental Management AB - The surface infiltration rates (SIR) of permeable pavements decline with time as sediment and debris clog pore spaces. Effective maintenance techniques are needed to ensure the hydraulic functionality and water quality benefits of this stormwater control. Eight different small-scale and full-scale maintenance techniques aimed at recovering pavement permeability were evaluated at ten different permeable pavement sites in the USA and Sweden. Maintenance techniques included manual removal of the upper 2 cm of fill material, mechanical street sweeping, regenerative-air street sweeping, vacuum street sweeping, hand-held vacuuming, high pressure washing, and milling of porous asphalt. The removal of the upper 2 cm of clogging material did not significantly improve the SIR of concrete grid paves (CGP) and permeable interlocking concrete pavers (PICP) due to the inclusion of fines in the joint and bedding stone during construction, suggesting routine maintenance cannot overcome improper construction. For porous asphalt maintenance, industrial hand-held vacuum cleaning, pressure washing, and milling were increasingly successful at recovering the SIR. Milling to a depth of 2.5 cm nearly restored the SIR for a 21-year old porous asphalt pavement to like-new conditions. For PICP, street sweepers employing suction were shown to be preferable to mechanical sweepers; additionally, maintenance efforts may become more intensive over time to maintain a threshold SIR, as maintenance was not 100% effective at removing clogging material. DA - 2016/// PY - 2016/// DO - 10.1016/j.jenvman.2015.12.026 VL - 169 SP - 132-144 ER - TY - JOUR TI - Study on an improved bio-electrode made with glucose oxidase immobilized mesoporous carbon in biofuel cells AU - Yang, Xuewei AU - Yuan, Wenqiao AU - Li, Dawei AU - Zhang, Xiangwu T2 - RSC ADVANCES AB - Response surface methodology (RSM) was used for process optimization to immobilize glucose oxidase (GOx) on ordered mesoporous carbon (OMC). DA - 2016/// PY - 2016/// DO - 10.1039/c5ra27111h VL - 6 IS - 29 SP - 24451-24457 SN - 2046-2069 ER - TY - JOUR TI - Determination and modeling of contact angle of Canola oil and olive oil on a PTFE surface at elevated temperatures using air or steam as surrounding media AU - Aydar, Alev Y. AU - Rodriguez-Martinez, Veronica AU - Farkas, Brian E. T2 - LWT-FOOD SCIENCE AND TECHNOLOGY AB - Contact angles (CAs) of unused Canola and olive oils on polytetrafluoroethylene (PTFE) were measured, and the effect of oil type, surrounding media, and temperature evaluated. CAs were compared to values predicted by Girifalco-Good-Fowkes-Young (GGFY) equation, and GGFY combined with the Eötvös equation (GGFY-E). Finally, a relationship between the CA and interfacial tension for each oil type was obtained. CAs were measured by the sessile drop method (ramé-hart instrument co.). For oil-air systems, measurements were performed at 23 ± 1 °C, 40 °C, and then every 20 °C until reaching the oils' smoke point (olive oil: 180 °C, Canola oil: 200 °C). The same procedure was followed for oil-steam systems with first and second temperatures of 110 and 120 °C, respectively. Temperature and oil type had a significant effect (P < 0.05) on CAs, while no significant effect of surrounding media was observed. CAs decreased linearly as temperature increased (approximately 0.2°/°C). Error (E%) values were less than 10% for the majority of Canola oil systems and olive oil-air predicted CAs. Using Zisman plots, PTFE's surface tension estimates were determined using Canola and olive oil air systems (16.0 and 18.2 mN/m respectively); both systems showed a linear correlation (r2 = 0.99) between interfacial tension and CA. DA - 2016/1// PY - 2016/1// DO - 10.1016/j.lwt.2015.08.022 VL - 65 SP - 304-310 SN - 1096-1127 KW - Contact angle KW - Interfacial tension KW - Vegetable oil KW - Steam KW - High temperature ER - TY - JOUR TI - Modeling bubble dynamics and radical kinetics in ultrasound induced microalgal cell disruption AU - Wang, Meng AU - Yuan, Wenqiao T2 - ULTRASONICS SONOCHEMISTRY AB - Microalgal cell disruption induced by acoustic cavitation was simulated through solving the bubble dynamics in an acoustical field and their radial kinetics (chemical kinetics of radical species) occurring in the bubble during its oscillation, as well as calculating the bubble wall pressure at the collapse point. Modeling results indicated that increasing ultrasonic intensity led to a substantial increase in the number of bubbles formed during acoustic cavitation, however, the pressure generated when the bubbles collapsed decreased. Therefore, cumulative collapse pressure (CCP) of bubbles was used to quantify acoustic disruption of a freshwater alga, Scenedesmus dimorphus, and a marine alga, Nannochloropsis oculata and compare with experimental results. The strong correlations between CCP and the intracellular lipid fluorescence density, chlorophyll-a fluorescence density, and cell particle/debris concentration were found, which suggests that the developed models could accurately predict acoustic cell disruption, and can be utilized in the scale up and optimization of the process. DA - 2016/1// PY - 2016/1// DO - 10.1016/j.ultsonch.2015.06.025 VL - 28 SP - 7-14 SN - 1873-2828 KW - Acoustic cavitation KW - Bubble dynamics KW - Cell disruption KW - Microalgae KW - Radical kinetics ER -