TY - CONF TI - What We Know and What We Don’t Know about Microbial Pathogens Associated with Confined Animal Agriculture AU - Simmons, O.D., III T2 - National Pork Board Meeting: Water Quality Research Meeting C2 - 2008/5// CY - Des Moines, IA DA - 2008/5// PY - 2008/5// ER - TY - CONF TI - Methods to Monitor Source Water for Microbial Contaminants AU - Simmons, O.D., III T2 - North Carolina Forum on Water Quality Monitoring (NCforWater) C2 - 2008/// CY - Charlotte, NC DA - 2008/// PY - 2008/// ER - TY - CONF TI - Improved Hollow-fiber Ultrafiltration and Real-time PCR Detection for the Recovery and Detection of Waterborne Microbes AU - Casteel, M.J. AU - Guarin, H.G. AU - Simmons, O.D., III T2 - Society for Industrial Microbiology Annual Meeting and Exhibition C2 - 2008/// DA - 2008/// PY - 2008/// ER - TY - CONF TI - Optimized Secondary Concentration of Adenovirus and Echovirus by Polyethylene glycol (PEG) Precipitation of Primary Water Concentrates AU - Lee, H. AU - Simmons, O.D., III AU - Sobsey, M.D. T2 - 108th General Meeting American Society for Microbiology C2 - 2008/6/1/ CY - Boston, MA DA - 2008/6/1/ PY - 2008/6/1/ ER - TY - CONF TI - Improved Recovery of Multiple Microbial Indicator Organisms from Source and Treated Drinking Waters by Optimized Hydraulic Modification to Hollow-fiber Ultrafilters AU - Andersen, E. AU - Lee, H. AU - Casteel, M.J. AU - Sobsey, M.D. AU - Simmons, O.D., III T2 - 108th General Meeting American Society for Microbiology C2 - 2008/6/1/ CY - Boston, MA DA - 2008/6/1/ ER - TY - RPRT TI - Recent Changes in Food Animal Production and Impacts on Animal Waste Management AU - Bull, L.S. AU - Meyer, D. AU - Rice, J.M. AU - Simmons, O.D., III A3 - Pew Commission on Industrial Farm Animal Production DA - 2008/// PY - 2008/// VL - Putting Meat on the Table: Industrial Farm Animal Production in America M3 - Pew Commission on Industrial Farm Animal Production Technical Report PB - Pew Commission on Industrial Farm Animal Production UR - http://www.pcifapia.org/_images/PCIFAP_FW_FINAL1.pdf ER - TY - CONF TI - Surface water and groundwater interactions: Investigating the connections AU - Fox, G.A. T2 - 2008 ASABE Annual International Meeting A2 - Skaggs, R.W. C2 - 2008/// C3 - Centennial Session on Advances in Soil and Water Engineering DA - 2008/// PY - 2008/6/30/ ER - TY - CONF TI - Assessing the Impact of Riparian Soil-Water Dynamics on Streambank Erosion AU - Langendoen, E.J. AU - Wilson, G.V. AU - Fox, G.A. T2 - 2008 AWRA Summer Specialty Conference A2 - Okay, J. A2 - Todd, A. C2 - 2008/// C3 - Riparian Ecosystems and Buffers: Working at the Water's Edge, Proceedings 2008 AWRA Summer Specialty Conference CY - Virginia Beach, Viriginia DA - 2008/// PY - 2008/6/30/ ER - TY - RPRT TI - Vermicomposting leader's guide: A 5th grade school enrichment curriculum AU - Sherman, R. AU - Liverman, R. AU - Maxa, E. A3 - NC Cooperative Extension DA - 2008/// PY - 2008/// M1 - E08‐50326/4H‐16‐14PW PB - NC Cooperative Extension SN - E08‐50326/4H‐16‐14PW ER - TY - CONF TI - Optimizing estimates of soil moisture for irrigation scheduling AU - Sayde, C. AU - Khoury, L. AU - Gitelman, A. AU - English, M. T2 - ASABE Annual International Meeting AB - Irrigation scheduling commonly involves a water balance analysis in which daily estimates of ET are used to compute cumulative soil water depletion, and occasional soil moisture measurements are used to correct the estimate of depletion. However, both ET estimates and soil moisture measurements are characterized by significant uncertainty, and both produce uncertain estimates of depletion. When water use is not limited the problem of uncertainty can be avoided by maintaining soil moisture at higher than critical levels, relying on moisture measurements to decide when to irrigate, and keeping some soil water in reserve as a hedge against uncertainty. On the other hand, deficit irrigation, an increasingly common strategy for maximizing net economic returns to limited water, must be managed differently. Deficit irrigation strategies allow the crop to be stressed to some degree,which implies there will be no soil moisture held in reserve. But errors in management of crop stress can be costly. C2 - 2008/6/29/ C3 - Proceedings of the 2008 ASABE Annual International Meeting CY - Providence, RI DA - 2008/6/29/ PY - 2008/6/29/ DO - 10.13031/2013.25158 M1 - 084699 PB - American Society of Agricultural and Biological Engineers ER - TY - CHAP TI - Effect of a nonlinear runoff response on flood statistical properties: the case of a tile-drained watershed AU - Augeard, B. AU - Kao, C. AU - Chaumont, C. AU - Ansart, P. AU - Nédélec, Y. AU - Birgand, F. T2 - Groundwater-surface water interaction : process understanding, conceptualization and modeling A2 - Abesser, Corinna A2 - Wagener, Thorsten A2 - Nuetzmann, Gunnar PY - 2008/// SP - 124-133 PB - IAHS Press SN - 978-1-901502-59-6 ER - TY - JOUR TI - Quantification et maîtrise des flux de nitrates : de la parcelle drainée au bassin versant AU - Tournebize, J. AU - Arlot, M. AU - Billy, C. AU - Birgand, F. AU - Gillet, J. AU - Dutertre, A. T2 - Ingénieries : eau agriculture territoires - Numéro Spécial Azote, Phosphore et pesticides DA - 2008/// PY - 2008/// SP - 5–25 ER - TY - RPRT TI - Restoring the Burnt Mill Creek Watershed through Stormwater Management and Community Development AU - Perrin, C. AU - Wright, J.D. AU - Hunt, W.F. AU - Beggs, P. AU - Mallin, M. AU - Burchell, M.R. DA - 2008/8// PY - 2008/8// M1 - FY04 EPA 319 Grant. NCDENR Contract EW05023 M3 - Final Report SN - FY04 EPA 319 Grant. NCDENR Contract EW05023 ER - TY - JOUR TI - Comparing the partitioning behavior of Giardia and Cryptosporidium with that of indicator organisms in stormwater runoff AU - Cizek, Adrienne R. AU - Characklis, Gregory W. AU - Krometis, Leigh-Anne AU - Hayes, Jeffrey A. AU - Simmons, Otto D., III AU - Di Lonardo, Steve AU - Alderisio, Kerri A. AU - Sobsey, Mark D. T2 - Water Research AB - Microbial association with particles can significantly affect the fate and transport characteristics of microbes in aquatic systems as particle-associated organisms will be less mobile in the environment than their free phase (i.e. unattached) counterparts. As such, similarities or dissimilarities in the partitioning behavior of indicator organisms and pathogens may have an impact on the suitability of a particular indicator to act as a surrogate for a pathogen. This research analyzed the partitioning behavior of two pathogens (Cryptosporidium, Giardia) and several common indicator organisms (fecal coliform, Escherichia coli, Enterococci, Clostridium perfringens spores, and coliphage) in natural waters under both dry and wet weather conditions. Samples were taken from several streams in two distinct sampling phases: (i) single grab samples; and (ii) intrastorm samples obtained throughout the duration of four storms. Partitioning behavior varied by microbial type, with 15–30% of bacterial indicators (fecal coliform, E. coli, and Enterococci) associated with settleable particles compared to 50% for C. perfringens spores. Both pathogens exhibited similar levels of particle association during dry weather (roughly 30%), with increased levels observed during wet weather events (Giardia to 60% and Cryptosporidium to 40%). The settling velocities of particle-associated microbes were also estimated, with those of the bacterial indicators (fecal coliform, E. coli, and Enterococci), as well as C. perfringens spores, being similar to that of the Giardia and Cryptosporidium, suggesting these organisms may exhibit similar transport behavior. With respect to intrastorm analysis, the highest microbial concentrations, in both particle-associated and free phase, occurred during the earlier stages of a storm. The total loadings of both indicators and pathogens were also estimated over the course of individual storms. DA - 2008/11// PY - 2008/11// DO - 10.1016/j.watres.2008.06.020 VL - 42 IS - 17 SP - 4421-4438 J2 - Water Research LA - en OP - SN - 0043-1354 UR - http://dx.doi.org/10.1016/j.watres.2008.06.020 DB - Crossref KW - Stormwater KW - Microbial partitioning KW - Microbial loading KW - Settleable solids KW - Indicator organisms KW - Cryptosporidium KW - Giardia KW - Pathogens ER - TY - JOUR TI - Investigation of Bioaerosols Released from Swine Farms using Conventional and Alternative Waste Treatment and Management Technologies AU - Ko, GwangPyo AU - Simmons III, Otto D. AU - Likirdopulos, Christina A. AU - Worley-Davis, Lynn AU - Williams, Mike AU - Sobsey, Mark D. T2 - Environmental Science & Technology AB - Microbial air pollution from concentrated animal feeding operations (CAFOs) has raised concerns about potential public health and environmental impacts. We investigated the levels of bioaerosols released from two swine farms using conventional lagoon-sprayfield technology and ten farms using alternative waste treatment and management technologies in the United States. In total, 424 microbial air samples taken at the 12 CAFOs were analyzed for several indicator and pathogenic microorganisms, including culturable bacteria and fungi, fecal coliform, Escherichia coli, Clostridium perfringens, bacteriophage, and Salmonella. At all of the investigated farms, bacterial concentrations at the downwind boundary were higher than those at the upwind boundary, suggesting that the farms are sources of microbial air contamination. In addition, fecal indicator microorganisms were found more frequently near barns and treatmenttechnology sites than upwind or downwind of the farms. Approximately 4.5% (19/424), 1.2% (5/424), 22.2% (94/424), and 12.3% (53/424) of samples were positive for fecal coliform, E. coli, Clostridium, and total coliphage, respectively. Based on statistical comparison of airborne fecal indicator concentrations at alternative treatment technology farms compared to control farms with conventional technology, three alternative waste treatment technologies appear to perform better at reducing the airborne release of fecal indicator microorganisms during on-farm treatment and management processes. These results demonstrate that airborne microbial contaminants are released from swine farms and pose possible exposure risks to farm workers and nearby neighbors. However, the release of airborne microorganisms appears to decrease significantly through the use of certain alternative waste management and treatment technologies. DA - 2008/12// PY - 2008/12// DO - 10.1021/es801091t VL - 42 IS - 23 SP - 8849-8857 J2 - Environ. Sci. Technol. LA - en OP - SN - 0013-936X 1520-5851 UR - http://dx.doi.org/10.1021/es801091t DB - Crossref ER - TY - CONF TI - A Feedback System to Optimize Crop Water Use Estimates in Irrigation Scheduling AU - English, Marshall AU - Sayde, Chadi AU - Gitelman, Alix AU - El Khoury, Laureine T2 - World Environmental and Water Resources Congress 2008 AB - This paper deals with errors in estimation of soil water depletion inirrigation management. Such errors can reduce net economic returns to water, increase economic risk and motivate risk averse farm managers to adopt less profitable strategies. Two common methods of estimating depletion are discussed, one based on cumulative ET the other on soil moisture measurements. Both are characterized by significant uncertainty. It is common practice to rely on one or the other of these estimators for irrigation scheduling. This paper proposes an alternative approach that utilizes both estimators in combination. Rather than treating them as deterministic quantities, they are treated as random variables. The probability distributions of each are combined in a Bayesian analysis to derive a probability distribution of depletion, which then provides a better basis for irrigation decisions. C2 - 2008/5// C3 - World Environmental and Water Resources Congress 2008 CY - Honolulu, Hawaii DA - 2008/5// PY - 2008/5/12/ DO - 10.1061/40976(316)104 PB - American Society of Civil Engineers SN - 9780784409763 UR - http://dx.doi.org/10.1061/40976(316)104 DB - Crossref ER - TY - JOUR TI - Catalytic Ozonation of Propanal Using Wood Fly Ash and Metal Oxide Nanoparticle Impregnated Carbon AU - Kastner, James R. AU - Ganagavaram, Rangan AU - Kolar, Praveen AU - Teja, Amyn AU - Xu, Chunbao T2 - Environmental Science & Technology AB - Catalytic ozonation of propanal at ambient temperatures (23-25 degrees C) was investigated by varying propanal and ozone concentrations and catalyst type. The catalysts tested included wood fly ash (WFA), magnetically separated ash, synthetic hematite and magnetite, and metal oxide nanoparticle impregnated activated carbon and peanut hull char. A power law model independent of ozone concentration for WFA (r(w), moles g(-1) s(-1)) and magnetite (r(m)) were, respectively, r(w) = k'(w) C(R(0.89)) and r(m) = k'(m)C(R(1.55)), where kw, and k'(m) were 2.36 x 10(-6) g(-1) s(-1) (moles)(-0.11) (m3)(0.89) and 6.5 x 10(-4) g(-1) s(-1) (moles)(-0.55) (m3)(1.55), respectively (5-15 ppmv). Magnetite and hematite present in the WFA were theorized to be the primary active sites, since magnetically separated WFA had a significantly higher reaction rate (approximately 12x, mol m(-2) s(-1)) than that of WFA. X-ray diffraction analysis demonstrated a qualitative increase in magnetite and hematite in the magnetically separated ash, and synthetic magnetite and hematite had reaction rates >80x and 200x that of WFA or activated carbon (surface area basis). Supercritical deposition of hematite on/in peanut hull char successfully generated a porous, pelleted catalystfrom an agricultural residue capable of oxidizing propanal at rates 12x activated carbon and similar to commercially available catalysts (per mass basis). Water vapor significantly increased the propanal reaction rate when using wood fly ash and activated carbon. DA - 2008/1// PY - 2008/1// DO - 10.1021/es0707512 VL - 42 IS - 2 SP - 556-562 J2 - Environ. Sci. Technol. LA - en OP - SN - 0013-936X 1520-5851 UR - http://dx.doi.org/10.1021/es0707512 DB - Crossref ER - TY - CONF TI - Evaluation of Evapotranspiration-Based and Soil-Moisture-Based Irrigation Control in Turf AU - Grabow, Garry L. AU - Vasanth, Arjun AU - Bowman, Dan AU - Huffman, Rodney L. AU - Miller, Grady L. T2 - World Environmental and Water Resources Congress 2008 AB - A study was initiated in Fall 2006 in Raleigh, North Carolina to compare two types of commercially available irrigation control technologies, one based on estimates of evapotranspiration (ET) and the other based on feedback from soil moisture sensors. Water applied and turf quality from one ET-based system and two sensor-based systems were compared to a system using a standard time-based irrigation schedule. The effect of irrigation frequency was also a part of the study. Estimates of turf ET were obtained from the Penman-Monteith equation using on-site weather data, and also from an atmometer. Results from the twenty week evaluation in 2007 showed that on average the "add-on" soil-moisture-based system evaluated applied the least amount of water while the ET-based system evaluated applied the most water. Weekly irrigation frequencies used the least amount of water, followed by bi-weekly and daily frequencies in increasing amounts when averaged across all technologies. Minimally acceptable turf quality was maintained by all technologies and frequencies through most of the study, but turf quality declined substantially the last month of the study for the add-on system and standard timer-based system. The "on-demand" sensor-based system resulted in the best combination of water efficiency and turf quality. C2 - 2008/5// C3 - World Environmental and Water Resources Congress 2008 DA - 2008/5// DO - 10.1061/40976(316)117 PB - American Society of Civil Engineers SN - 9780784409763 UR - http://dx.doi.org/10.1061/40976(316)117 DB - Crossref ER - TY - CONF TI - Stormwater Concepts — No Adverse Impact AU - Traver, Robert G. AU - Davis, Allen P. AU - Hunt, William F. AU - Cheng, Mow-Soung T2 - International Low Impact Development Conference 2008 AB - The scope and expectations of Stormwater Management have changed dramatically in the last few years, moving away from a purely flood control perspective toward a green infrastructure approach protecting the sustainability of our rivers and watersheds (PaDEP 2006). The first transition occurred when we as a profession realized that we could start to address water quality issues in our flood control based detention facilities, by creating naturalized basins or stormwater wetlands. Our next advance has been to integrate Low Impact Development concepts, such as pervious pavements, green roofs and bioretention, into the landscape to minimize the adverse effects of land form change and to address stormwater volume. As our profession becomes more confident in the performance and longevity of our BMP tools, we are again progressing, moving toward a "No Net Impact", or better stated, "No Adverse Impact" design goal. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)77 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)77 DB - Crossref ER - TY - CONF TI - Reducing Stormwater Bacteria Loads to North Carolina Ocean Recreational Areas Using a Dune Infiltration System AU - Burchell, M. R. AU - Hunt, III, W. F. AU - Chescheir, G. M. T2 - World Environmental and Water Resources Congress 2008 AB - Coastal towns traditionally discharge stormwater containing bacteria and pathogens to the ocean via ocean outfalls, increasing the potential for serious diseases to recreational swimmers. To combat this risk, an innovative coastal BMP, a Dune Infiltration System (DIS), was designed and installed at two locations in Kure Beach, N.C. to divert stormwater from outfalls into the dunes. Post-construction monitoring of these systems during 25 storm events in 2006 showed that this design was economically and technically feasible, because 97% of the stormwater was diverted into the dunes, the dunes remained structurally stable, and Enterococcus concentrations entering from the outfalls were reduced by over 97%. However bacterial transport surrounding the system remained poorly understood, which limited the certainty at which this system could be recommended for further implementation. Therefore, a series of additional water table and water quality wells were installed at each of the systems, and in a nearby control dune, during the summer of 2007. After six-months, bacterial concentrations in the groundwater at the dune-beach interface near the dune infiltration sites are similar to that of the control area. C2 - 2008/5// C3 - World Environmental and Water Resources Congress 2008 DA - 2008/5// DO - 10.1061/40976(316)34 PB - American Society of Civil Engineers SN - 9780784409763 UR - http://dx.doi.org/10.1061/40976(316)34 DB - Crossref ER - TY - CONF TI - Bioretention Performance in the Upper Coastal Plain of North Carolina AU - Brown, R. A. AU - Hunt, W. F. T2 - International Low Impact Development Conference 2008 AB - Bioretention is a principal low impact development (LID) practice. A study underway in North Carolina is examining the performance of bioretention cells with respect to hydrology and water quality under varying vegetative covers and media depths in the sandy in-situ soils of the upper coastal plain. Two types of cells are being monitored in both Rocky Mount and Nashville. In Rocky Mount, the cells were designed with 0.9 m deep media depth and a 0.6 m deep internal water storage layer (IWS). The IWS is intended to create anaerobic conditions to increase the rate of nitrate and total nitrogen reduction. Current data shows the IWS having a strong effect on flow reduction. Out of 37 events that were monitored since September 2007, outflow was generated in the grassed cell and mulch/shrub cell two and one time, respectively. Grab samples have been collected from the underdrains after an event to quantify treatment. Preliminary data from ten events show concentration reductions of total nitrogen, total phosphorus, and total suspended solids of 80, 72, and 92%, respectively. In Nashville, two sets of cells were designed without IWS and with media depths of 0.6 and 0.9 m. Preliminary data shows the deeper media depths meet a LID hydrology goal of volume reduction more frequently. Data collected from these four sets of cells will be used to compare performance of bioretention in the sandy in-situ soils of the upper coastal plain to those sited in clayey soils from past studies in the Piedmont region. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)95 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)95 DB - Crossref ER - TY - CONF TI - Effect of Bioretention on Runoff Temperature in Trout Sensitive Regions AU - Jones, Matthew AU - Hunt, William F. T2 - International Low Impact Development Conference 2008 AB - Although it has been established that thermal pollution from urban stormwater can negatively impact the aquatic ecosystem, there are few mechanisms available to reduce the temperature or urban stormwater runoff. A monitoring study was conducted at 4 bioretention areas in western North Carolina, located along the southeastern extent of United States trout populations, to examine the effect these systems have on runoff temperature and identify any design criteria pertinent to temperature reduction. Median runoff temperatures leaving the pavement surfaces, based on storm events, exceeded the 21°C upper avoidance temperature of trout at all sites during the months of June through September. Of the bioretention areas studied, the two systems that covered an area smaller than 10% of their contributing watershed were able to significantly (p<0.01) reduce both maximum and median storm temperatures between the inlet and outlet. At the two bioretention areas that were larger than 10% of their contributing watershed area, maximum effluent temperatures were significantly (p<0.01) cooler than influent temperatures; however, there was no significant (p<0.05) difference between median influent and effluent temperatures. Despite reductions in temperature, effluent temperatures were not significantly (p<0.05) cooler than the upper avoidance temperature for trout at any of the monitoring locations. There was evidence that substantial reductions in runoff volume occurred at all bioretention areas, especially the systems that were larger than 10% of their contributing watershed. Overall, monitoring results indicated that bioretention areas served as effective treatment mechanisms for reducing, but not eliminating, the thermal impacts associated with urban stormwater runoff. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)80 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)80 DB - Crossref ER - TY - CONF TI - Stormwater BMP Maintenance and Certification Program in North Carolina, USA AU - Lord, W. G. AU - Hunt, W. F. T2 - International Low Impact Development Conference 2008 AB - Stormwater practices are being installed across the world and studies show they are not being properly inspected and maintained. If not properly maintained, stormwater practices will not perform as intended, but minimal guidance on maintenance procedures is available. In North Carolina, U.S.A., the North Carolina State University Cooperative Extension Service has developed a 1.5 day training and certification program that has certified approximately 500 design, local government, and landscape maintenance professionals and practitioners in stormwater practice inspection and maintenance. To date the response has been very favorable, as several communities now require the certification for anyone who designs and/or maintains stormwater practices. Officials with the state of North Carolina have incorporated designing for inspection and maintenance as part of their stormwater practice review. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)64 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)64 DB - Crossref ER - TY - CONF TI - Performance of Rainwater Harvesting Systems in the Southeastern United States AU - Jones, Matthew AU - Hunt, William F. T2 - International Low Impact Development Conference 2008 AB - Due to recent concerns over the environmental impact of stormwater runoff and increased water demands, interest in rainwater harvesting systems has developed in humid, well developed regions, such as the southeastern United States. In order to better understand the anticipated usage and reliability of rainwater harvesting systems in the southeastern United States, a monitoring study was conducted at 3 rainwater harvesting systems in North Carolina, measuring cistern water levels and rainfall. Results of the monitoring study showed that the rainwater harvesting systems were typically underutilized. Water usage was most consistent at the location where harvested rainwater was used to flush a toilet; however, the water level within the cistern only dropped below 80% of capacity on one occasion during the 30 month monitoring period. A computer model was developed to simulate the performance of rainwater harvesting systems based upon historical rainfall data and anticipated usage by evaluating a daily or hourly water balance. The rainwater harvesting computer model was used to simulate the performance of a 55-gallon (208 liter) rain barrel commonly used by homeowners in this region to meet household gardening demands. A variety of turfgrass irrigation scenarios were examined, varying the size of the irrigated area and contributing rooftop. Simulation results showed that the rain barrel was not able to adequately meet irrigation demands. The low volume of water the rain barrel was able to supply for irrigation and the large amount of overflow indicated that the rain barrel was not able to effectively utilize the potential water supply coming from the rooftop and provided minimal runoff volume reduction. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)30 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)30 DB - Crossref ER - TY - CONF TI - Hydrologic and Water Quality Evaluation of Four Permeable Pavements in North Carolina, USA AU - Collins, Kelly A. AU - Hunt, William F. AU - Hathaway, Jon M. T2 - International Low Impact Development Conference 2008 AB - A permeable pavement parking lot in eastern North Carolina consisting of four types of permeable pavement and standard asphalt was monitored from June 2006 to July 2007 for hydrologic differences in pavement surface runoff volumes, total outflow volumes, peak flow rates, and time to peak, and from January 2007 to July 2007 for water quality concentrations. The four permeable sections were pervious concrete (PC), two types of permeable interlocking concrete pavement (PICP) with small-sized aggregate in the joints and having 12.9% (PICP1) and 8.5% (PICP2) open surface area, and concrete grid pavers (CGP) filled with sand. The site was located in poorly drained soils, and all permeable sections were underlain by a crushed stone base layer with a perforated underdrain. All permeable pavements significantly and substantially reduced surface runoff volumes and peak flow rates from those of asphalt (p<0.01). Of the permeable pavements, CGP generated the greatest surface runoff volumes (p<0.01). The PICP1 and CGP cells generated significantly lower outflow volumes than all other sections evaluated (p<0.01), and had the lowest peak flows and the longest time to peak. The response of the PICP1 cell was likely due to an increased base storage volume resulting from an elevated pipe underdrain; whereas, the CGP cell response was attributed to water retention in the sand fill layer. Overall, different permeable pavement sections performed similarly, but were substantially different from asphalt. Subtle differences in the performance of CGP were primarily due to the characteristics of the sand filled media compared to small aggregate typically used in PC and PICP joints and bedding. The pH of permeable pavement subsurface drainage was higher than that of asphalt runoff (p<0.01) with the PC cell having the highest pH values (p<0.01). Permeable pavement subsurface drainage had lower NH4-N (p<0.01) and TKN concentrations than asphalt runoff and atmospheric deposition. With the exception of the CGP cell, permeable pavements had higher NO2,3-N concentrations than asphalt (p<0.01), a probable result of nitrification occurring within the permeable pavement profile. The CGP cell had the lowest mean TN concentrations; however, results were not significantly different from those of asphalt runoff. Overall, different permeable pavement sections performed similarly to one another with respect to water quality, but the CGP cell appeared to improve stormwater runoff nitrogen concentrations. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)27 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)27 DB - Crossref ER - TY - CONF TI - Low Impact Development and Permeable Interlocking Concrete Pavements: Working with Industry for Material Development and Training Offerings AU - English, Ann AU - Hunt, William F. T2 - International Low Impact Development Conference 2008 AB - Green infrastructure supports the concept of using natural ecosystems to support a healthy urban environment, specifically to preserve and enhance water, air, cultural and visual resources. Low impact development (LID) is implemented through a set of tools which support the development and enhancement of green infrastructure. Permeable interlocking concrete pavement (PICP) is an LID tool which enables a broad range of opportunities to support integrated green infrastructure goals in new and redeveloped urban environments while meeting regulatory directives and other drivers for implementation. PICP has a variety of design options for stormwater mitigation, increased infiltration, and pollutant control. It is essential for users, and potential users, of this product to fully understand PICP benefits and constraints. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)22 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)22 DB - Crossref ER - TY - CONF TI - Implementation of Low Impact Development Retrofits in a Low Income Neighborhood in Wilmington, NC AU - Wright, J. D. AU - Perrin, C. A. AU - Hunt, W. F. AU - McCoy, E. R. T2 - International Low Impact Development Conference 2008 AB - Burnt Mill Creek is on the EPA's 303(d) list for impairment due to urban stormwater runoff. Located within downtown Wilmington, NC the urban nature of the watershed presents challenges for restoration because of the varying land uses including single and multi-family residential areas, recreational parks, and commercial and industrial areas. Restoration efforts are multiplying in Burnt Mill Creek as a result of passionate involvement from local community leaders and partnerships with state organizations. Watershed Education for Communities and Local Officials (WECO) of NC State University (NCSU) coordinated a partnership with NCSU Department of Biological and Agricultural Engineering (BAE), the City of Wilmington, as well as several other key state and local organizations and citizens groups, to obtain an EPA 319 grant that addresses stormwater management in the watershed. Collaboration with community leaders has led to several retrofit opportunities and successful partnerships. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)115 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)115 DB - Crossref ER - TY - CONF TI - LID Feasibility, Design, and Implementation at Cape Lookout National Seashore AU - Wright, J. D. AU - Hunt, W. F. T2 - International Low Impact Development Conference 2008 AB - The grounds surrounding the Core Sound Waterfowl Museum and the Cape Lookout National Seashore Visitor Center provide little stormwater runoff treatment as they are currently configured. Because both facilities are immediately adjacent to Core Sound and Back Sound, any pollutants that fall on the grounds, particularly on impermeable surfaces, can easily migrate to sensitive waters. Also, as thousands of visitors pass through the National Park Service property each year, there is a tremendous opportunity to demonstrate low impact development practices to reduce the amount of runoff, and its associated pollutants, entering the sounds. Faculty and students from the Department of Biological and Agricultural Engineering Department at NC State University evaluated the site for potential best management practices. They identified 13 potential retrofits for the Core Sound Waterfowl Museum and the Cape Lookout Visitor Center including water harvesting, rain gardens, and permeable pavement. Design elements including a cost estimate for each potential BMP has been developed for future use by the visitor center and the museum. Detailed designs were completed for five of the identified BMP's including two rain gardens, a water harvesting system, and permeable pavement. Three of the BMP's were installed: one at the Cape Fear Visitor Center and two at the Core Sound Waterfowl Museum. An 7.5 m2 (80 ft2) rain garden was constructed that treats the runoff from a rooftop at the museum. A 5,678 L (1,500 gal) cistern was installed that captures runoff from 70 m2 (750 ft2) of rooftop at the museum. The harvested water will be used to irrigate the landscaping at the museum. Runoff from the rooftop at the Cape Lookout Visitor Center will be treated in a rain garden located near the entrance. Each of the practices will improve the quality of the stormwater leaving the site while serving to educate the public about using low impact development to treat stormwater runoff. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)105 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)105 DB - Crossref ER - TY - CONF TI - Lessons Learned: The North Carolina Backyard Rain Garden Program AU - Woodward, Mitch AU - Hunt, William F. AU - Hartup, Wendi T2 - International Low Impact Development Conference 2008 AB - Research conducted at the North Carolina State University and elsewhere has determined that bioretention practices are very effective in reducing polluted stormwater runoff from urban areas. Smaller residential bioretention areas, also known as rain gardens, have proven to be an effective means of removing metals, nutrients, sediment and fecal coliform provided that they have been designed, sited, constructed and maintained properly. The university, local and state governments have been promoting the installation of rain gardens and other stormwater practices in Phase I and II communities for many years; however, very few homeowners and commercial landscape contractors have a working knowledge of the benefits of rain gardens, their installation or their maintenance requirements. To help promote rain gardens and address these needs, the North Carolina Backyard Rain Garden Program was implemented during the summer of 2006 in a six-county pilot area. Funded as an EPA 319(h) project, the program (1) developed an education program by conducting homeowner workshops in each county, (2) installed more than 40 residential demonstration rain gardens, and (3) developed educational and reference materials making them available at the following website: www.bae.ncsu.edu/topic/rain_garden. More recently, an assessment was performed to determine: 1) How many rain gardens continued to function properly, 2) What, if any maintenance had been performed, 3) Common traits among the cooperators with successful rain gardens. 4) Education needs for homeowners and installers. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)104 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)104 DB - Crossref ER - TY - CONF TI - Field Evaluation of Level Spreaders for Runoff Reduction and Water Quality Impacts AU - Winston, Ryan J. AU - Hunt, William F. T2 - International Low Impact Development Conference 2008 AB - Traditional construction practices lead to degradation of watershed hydrology through increased flow in pipe networks, increased flow volumes, decreased groundwater recharge, and increased peak flows. Recent regulations in North Carolina have led to the use of level spreaders in combination with a vegetated buffer as an end-of-pipe method to reduce erosion and decrease stresses on riparian buffers. However, little research has been done to evaluate their effectiveness. A total of four level spreaders were studied at two sites, Apex and Louisburg, NC. At each site, stormwater from small, impervious watersheds (0.4 ha or less) was conveyed proportionally to two level spreaders. Flow was released along the length of the level spreaders and into two vegetated buffers. This study evaluated the hydrologic and water quality impacts of level spreaders (combined with vegetated buffers) as an LID practice. The idea is to disperse flow across the length of the buffer, in order to improve infiltration capacity of the buffer. Varying buffer widths and buffer vegetation were studied. Preliminary findings show that substantial reduction in peak flow rate and flow volume can be expected when this LID practice is implemented. This system was also studied for its impacts on nitrogen, phosphorous, suspended solids, and runoff temperature. Further data collection and analysis should provide design engineers guidance on the functionality of this system. C2 - 2008/11/10/ C3 - Low Impact Development for Urban Ecosystem and Habitat Protection DA - 2008/11/10/ DO - 10.1061/41009(333)100 PB - American Society of Civil Engineers SN - 9780784410097 UR - http://dx.doi.org/10.1061/41009(333)100 DB - Crossref ER - TY - CONF TI - Evaluation of Various Types of Permeable Pavement with Respect to Water Quality Improvement and Flood Control AU - Collins, Kelly A. AU - Hunt, William F. AU - Hathaway, Jon M. T2 - Second National Low Impact Development Conference AB - In North Carolina and several other U.S. states, all permeable pavements are currently considered to have similar capabilities in reducing runoff, but are not credited with improving water quality. Previous research conducted by the North Carolina State University on one particular permeable pavement type has shown that when compared to runoff from an adjoining asphalt lot, permeable pavement exfiltrate contained significantly lower concentrations of phosphorous and zinc, as well as reductions in total nitrogen. To further test various permeable pavement designs, a parking lot consisting of four different types of permeable pavements and standard asphalt was constructed in Kinston, NC. The permeable pavement sections consist of porous concrete (PC), permeable interlocking concrete pavers (PICP) with 8.5 % void space, PICP with 12.9 % void space, and concrete grid pavers (CGP), each covering a 1200 sq. ft. area with a 10 in. gravel storage layer. The purpose of this study is to evaluate and compare the effects of each pavement type on water quality and runoff reduction. Conclusions on the difference in reduction between each pavement type have not previously been determined. Site analyses on every rainfall event began in March, 2006, and will continue for one year. Preliminary results indicate significant peak flow and volume reductions in all permeable pavement exfiltrates. Additionally, there has been little to no runoff observed from any of the pervious sections. As a result of the Kinston study, it is expected that the state of North Carolina will be able to make an informed judgment on how much pollutant removal credit permeable pavements should receive when implemented as stormwater best management practices. Also, this study can be used to determine whether or not stormwater credit should vary based on pavement type. C2 - 2008/11/7/ C3 - Low Impact Development DA - 2008/11/7/ DO - 10.1061/41007(331)25 PB - American Society of Civil Engineers SN - 9780784410073 UR - http://dx.doi.org/10.1061/41007(331)25 DB - Crossref ER - TY - CONF TI - Evaluating a Spreadsheet Model to Predict Green Roof Stormwater Management AU - Jarrett, A. R. AU - Hunt, W. F. AU - Berghage, R. D. T2 - Second National Low Impact Development Conference AB - The departments of Agricultural and Biological Engineering and Horticulture at the Pennsylvania State University have combined efforts to quantify the stormwater attenuation capabilities of extensive green-roof systems. This green-roof system consisted of a roof with a conventional flat-roof covering, a 0.5-in thick Enka-drainage layer, 3.5 in of porous medium, and Sedum spurium planted 3.0 in on center. The combined layers of this green roof had a maximum retention of 1.5 in and a saturated hydraulic conductivity of 0.43 in/s. The green roof system was modeled using a checkbook approach with daily rainfall depth as an input and ET and runoff as the outputs. The AGRR model was applied to 28 years (1976–2003) of rainfall data in Raleigh, NC, and showed that 45% of the annual rainfall volume (depth) can be retained on the green roof. Increasing the volume of storage does not improve the roofs ability to retain rain water. Providing only 0.125 in of roof storage will still cause over 30% of the annual rain depth to be retained on the roof. C2 - 2008/11/7/ C3 - Low Impact Development DA - 2008/11/7/ DO - 10.1061/41007(331)23 PB - American Society of Civil Engineers SN - 9780784410073 UR - http://dx.doi.org/10.1061/41007(331)23 DB - Crossref ER - TY - CONF TI - Field Evaluation of Level Spreaders in the Piedmont of North Carolina AU - Hathaway, J. M. AU - Hunt, W. F. T2 - Second National Low Impact Development Conference AB - Level Spreaders are commonly used in combination with riparian buffers as a storm water Best Management Practice (BMP) in many parts of the United States. These systems have not been extensively studied in urban environments to determine if they can provide a long term water quality benefit. In Winter, 2005, 24 level spreaders were evaluated in the Piedmont of North Carolina. Detailed observations were made at 20 of these locations. The results of the study indicate that level spreaders may not be the versatile structure they are perceived to be. No level spreader — riparian buffer system was able to provide diffuse flow through the riparian buffer from the level spreader to the stream. Common causes for failure to maintain diffuse flow included: lack of maintenance (12 cases), poor design (11), riparian topography / content (11), level spreader lip not level (7), built with easily eroded materials (6), poor construction methods (3), and human interference (2). This field evaluation indicates that level spreader systems may need design revisions, construction guidance, and maintenance requirements before they continue to be used en masse. C2 - 2008/11/7/ C3 - Low Impact Development DA - 2008/11/7/ DO - 10.1061/41007(331)18 PB - American Society of Civil Engineers SN - 9780784410073 UR - http://dx.doi.org/10.1061/41007(331)18 DB - Crossref ER - TY - CONF TI - Pathogen Removal Performance of Best Management Practices in Charlotte and Wilmington, North Carolina AU - Hathaway, J. M. AU - Hunt, W. F. AU - Wright, J. D. AU - Jadlocki, S. J. T2 - World Environmental and Water Resources Congress 2008 AB - Pathogens are a target pollutant in many parts of North Carolina, particularly in areas that drain to shellfish waters. Single storm limits have been established for pathogen indicators in fresh water (200 cfu/100 ml for fecal coliform, 126 col/100 ml for E. coli, and 33 cfu/100 ml for enterrococcus) and marine waters (35 cfu/100 ml for enterrococcus) being used as full body recreational areas in an attempt to reduce public health risks. Runoff samples collected in coastal counties have often exceeded fecal counts of 20,000 cfu/100 ml. The NCSU Biological and Agricultural Engineering Department monitored 14 total stormwater BMPs, 9 in Charlotte, NC, and 5 in Wilmington, NC, to evaluate their efficiency with respect to indicator bacteria removal. The study locations included 2 bioretention areas, 4 stormwater wetlands, 3 wet ponds, 2 dry detention, and 3 proprietary BMPs. C2 - 2008/5// C3 - World Environmental and Water Resources Congress 2008 DA - 2008/5// DO - 10.1061/40976(316)648 PB - American Society of Civil Engineers SN - 9780784409763 UR - http://dx.doi.org/10.1061/40976(316)648 DB - Crossref ER - TY - CONF TI - Implementation and Performance of Stormwater Best Management Practice Retrofits in Wilmington, NC AU - Wright, J. D. AU - Hunt, W. F. AU - Burchell, II, M. R. AU - Perrin, C. A. T2 - World Environmental and Water Resources Congress 2008 AB - Burnt Mill Creek, located within downtown Wilmington, NC, is on the EPA's 303(d) list for impairment due to urban stormwater runoff. The urban nature of the watershed presents challenges for restoration because of the varying land uses including single and multi-family residential areas, recreational parks, and commercial and industrial areas. NC State University's Watershed Education for Communities and Local Officials (WECO) coordinated a partnership, with the NC State Biological and Agricultural Engineering Department, the City of Wilmington, and several other key state and local organizations and citizens groups, to obtain an EPA 319 grant that addresses stormwater management in the watershed. Community involvement has led to several retrofit BMP installations, including two bioretention cells installed in a parking lot, a stormwater wetland at a townhome community, and a stormwater wetland on City of Wilmington property. This paper describes the urban retro-fit BMPs that have been constructed and preliminary data collected at each site. C2 - 2008/5// C3 - World Environmental and Water Resources Congress 2008 DA - 2008/5// DO - 10.1061/40976(316)647 PB - American Society of Civil Engineers SN - 9780784409763 UR - http://dx.doi.org/10.1061/40976(316)647 DB - Crossref ER - TY - CONF TI - Water Quality and Hydrologic Benefits of Five Bioretention Cells in North Carolina AU - Hunt, William F. AU - Passeport, Elodie AU - Brown, Robert A. T2 - World Environmental and Water Resources Congress 2008 AB - Five bioretention cells were studied from 2004 through 2007 in central North Carolina. They were located in Charlotte (1), Graham (2), and Rocky Mount (2). The former three cells were located in the Piedmont and therefore were underlain by clay-influenced soils. The latter two cells were located in the Upper Coastal Plain, which were sand dominated. The cells differed by vegetation cover, media type, media depth, and underdrain configuration. The Charlotte cell was 1.2 m deep and filled with a sandy-loam soil. It was drained by conventional underdrains and vegetated by trees and shrubs and covered by mulch. The Graham cells were 0.6 and 0.9 m deep, employed a proprietary soil comprised primarily of expanded slate fines, and had an upturn in the underdrain to create a sump to temporarily store water. The two cells were turf covered. In Rocky Mount, both cells were 0.9 m deep and used a sand fill media (98% sand). Both cells employed an upturned underdrain, but one cell was vegetated by turf grass and the other cell was vegetated by trees and shrubs and covered in mulch. Substantial data have been collected for the cells in Charlotte and Graham, while data collection in Rocky Mount is on-going. To date, all five cells, despite their many different design elements, have been shown to reduce nutrient loads and concentrations, and reduce outflow volumes, as compared to inflow volumes. Important implications of the research are a continued refinement of bioretention performance standards, confirmation that grassed systems perform comparably well to tree and shrub systems (at least in the short term), and the role of an upturned drainage system, particularly in a somewhat sandy in situ soil. C2 - 2008/5// C3 - World Environmental and Water Resources Congress 2008 DA - 2008/5// DO - 10.1061/40976(316)6 PB - American Society of Civil Engineers SN - 9780784409763 UR - http://dx.doi.org/10.1061/40976(316)6 DB - Crossref ER - TY - CONF TI - Inspection and Maintenance Guidance for Manufactured BMPs AU - Hunt, William F. AU - England, Gordon AU - DeBruijn, Hans AU - Gee, Richard AU - Guo, Qizhong (George) AU - Lord, William AU - Miller, Mark AU - Mosheni, Omid AU - Perry, Scott T2 - World Environmental and Water Resources Congress 2008 AB - ASCE/EWRI has assembled a Task Committee on guidelines for certification of manufactured stormwater BMPs. A nine-member subcommittee for maintenance was tasked by the larger committee to develop maintenance guidelines for manufactured stormwater BMPs. The subcommittee has developed recommendations for manufactured BMP maintenance in the following seven areas: (1) designing for maintenance, (2) defining standard maintenance triggers, (3) defining maintenance fundamentals for all manufactured BMPs, (4) defining maintenance tasks by BMP design; hydrodynamic or filter design, (5) identifying entities best able to maintain manufactured BMPs, and training requirements, (6) identifying entities to train maintenance providers, and (7) reviewing recommended disposal techniques for captured pollutants. C2 - 2008/5// C3 - World Environmental and Water Resources Congress 2008 DA - 2008/5// DO - 10.1061/40976(316)19 PB - American Society of Civil Engineers SN - 9780784409763 UR - http://dx.doi.org/10.1061/40976(316)19 DB - Crossref ER - TY - CONF TI - Data Reporting Guidelines for Certification of Manufactured Stormwater BMPs AU - Roseen, Robert M. AU - Carrasco, Ernie AU - Cheng, Yuan AU - Hunt, Bill AU - Johnston, Charlene AU - Mailloux, Jim AU - Stein, Walt AU - Williams, Tim T2 - World Environmental and Water Resources Congress 2008 AB - With the increasing need for the independent field testing of proprietary devices comes the importance of consistent data reporting guidelines to be used when reporting to regulatory agencies. The need for standardized reporting is underscored by the tremendous impact the range of factors can have upon testing results. These factors include the testing environment, experimental design, testing methodologies, statistical analysis, and data presentation. The need for the consistency is underscored by the complex influence these factors have upon performance results. A clear and consistent data reporting approach can ensure that these biases are minimized, well understood, and that representative field testing can be effectively evaluated by the regulatory agency. Data Reporting guidelines presented here were developed as part of the ASCE/EWRI Committee on Guidelines for Certification of Manufactured Stormwater BMPs. C2 - 2008/5// C3 - World Environmental and Water Resources Congress 2008 DA - 2008/5// DO - 10.1061/40976(316)16 PB - American Society of Civil Engineers SN - 9780784409763 UR - http://dx.doi.org/10.1061/40976(316)16 DB - Crossref ER - TY - CONF TI - Stormwater BMP Maintenance and Certification Program in North Carolina, USA AU - Lord, William G. AU - Hunt, William F. T2 - World Environmental and Water Resources Congress 2008 AB - Stormwater practices are being installed across the world and studies show they are not being properly inspected and maintained. If not properly maintained, stormwater practices will not perform as intended, but minimal guidance on maintenance procedures is available. In North Carolina, U.S.A., the North Carolina State University Cooperative Extension Service has developed a 1.5 day training and certification program that has certified approximately 500 design, local government, and landscape maintenance professionals and practitioners in stormwater practice inspection and maintenance. To date the response has been very favorable, as several communities now require the certification for anyone who designs and/or maintains stormwater practices. Officials with the state of North Carolina have incorporated designing for inspection and maintenance as part of their stormwater practice review. C2 - 2008/5// C3 - World Environmental and Water Resources Congress 2008 DA - 2008/5// DO - 10.1061/40976(316)13 PB - American Society of Civil Engineers SN - 9780784409763 UR - http://dx.doi.org/10.1061/40976(316)13 DB - Crossref ER - TY - JOUR TI - Rapid quantitation of lipid in microalgae by time-domain nuclear magnetic resonance AU - Gao, Chunfang AU - Xiong, Wei AU - Zhang, Yiliang AU - Yuan, Wenqiao AU - Wu, Qingyu T2 - Journal of Microbiological Methods AB - A specific strain of Chlorella protothecoides has been studied in heterotrophic fermentation for increasing cell growth rate and lipid content for biodiesel production. For optimizing the process of fermentation to reduce costs of alga-based biodiesel production, rapid determination of lipid content in microalgal cells is critical. Nile Red (NR) staining and time-domain nuclear magnetic resonance (TD-NMR) have been investigated to quantitate the lipid content in C. protothecoides. Both methods were found feasible and simpler than gravimetric methods that are commonly employed. The TD-NMR method showed better agreement (R2 = 0.9973) with the measured values from lipid extraction experiments than the NR staining method (R2 = 0.9067). Additionally, the smaller standard deviations of the samples (≤ 0.36) analyzed by TD-NMR revealed that the method is accurate and reproducible. The application of TD-NMR for lipid quantitation in C. protothecoides opens up the possibility of determining lipid content in algal fermentation precisely and quickly. DA - 2008/12// PY - 2008/12// DO - 10.1016/j.mimet.2008.07.019 VL - 75 IS - 3 SP - 437-440 J2 - Journal of Microbiological Methods LA - en OP - SN - 0167-7012 UR - http://dx.doi.org/10.1016/j.mimet.2008.07.019 DB - Crossref KW - Biodiesel KW - Chlorella protothecoides KW - Lipid KW - Microalgae KW - Nile Red KW - Time-domain NMR ER - TY - JOUR TI - Degree-days as a tool to determine the heating requirement for channel catfish spawning in earthen ponds AU - Pawiroredjo, P. AU - Lamoureux, J. AU - Hall, S.G. AU - Tiersch, T.R. T2 - North American Journal of Aquaculture AB - Abstract Temperature and time are critical in determining when channel catfish Ictalurus punctatus will be physiologically ready to spawn (conditioned). Natural and hormone‐induced spawning can occur when the fish are held at, above, or below specific temperatures for a largely undetermined minimum period of time. This period of conditioning can also be described as the heating requirement for spawning. We used degree‐days as a standard unit to describe and quantify the heating requirement for channel catfish spawning, and we developed specific terminology and standard parameters to support the use of the degree‐day concept for channel catfish spawning. The heating requirements for spawning were quantified by (1) retrospectively calculating degree‐day values using previously collected data (2000–2003) from heated and ambient‐temperature ponds before and during the natural spawning season and (2) calculating degree‐days using data from fish conditioned for the 2004 natural spawning season at different thermal regimes in heated ponds at three threshold temperatures. These results were used to calculate spawning probabilities to enable future spawning predictions using degree‐days. The values calculated using the 21°C threshold were more consistent than those calculated using the two other thresholds: 18°C and 24°C. The heating requirements for spawning in heated ponds before the natural spawning season were not different from the requirements for spawning in ambient‐temperature ponds during the natural spawning season. Degree‐day guidelines for channel catfish spawning were proposed based on the results of the degree‐day calculations and spawning probabilities using a commercial definition that corresponded with the 21°C threshold. According to those guidelines, channel catfish spawning can begin in 0.04‐ha ponds in southern Louisiana after the accumulation of 57–172 degree‐days, with a median value of 99 degree‐days. DA - 2008/// PY - 2008/// DO - 10.1577/A07-003.1 VL - 70 IS - 3 SP - 328-337 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-48249150729&partnerID=MN8TOARS ER - TY - JOUR TI - Application of DRAINMOD-Ks-STMAX to predict deep chiseling effects on a drained southern alluvial soil AU - Moriasi, D.N. AU - Fouss, J.L. AU - Hall, S.G. AU - Kornecki, T.S. T2 - Applied Engineering in Agriculture DA - 2008/// PY - 2008/// VL - 24 IS - 2 SP - 193-202 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-42649134771&partnerID=MN8TOARS ER - TY - JOUR TI - Seepage caused tension failures and erosion undercutting of hillslopes AU - Chu-Agor, M.L. AU - Fox, G.A. AU - Cancienne, R.M. AU - Wilson, G.V. T2 - Journal of Hydrology AB - Seepage has been suggested as an important factor in gully and river bank erosion. This study investigated the underlying mechanisms of instability by seepage in laboratory studies. A 25-cm tall, 50-cm wide, and 20-cm long soil block with a focused inflow reservoir was constructed to investigate seepage gradient forces and the three-dimensional nature of seepage particle mobilization (i.e., seepage erosion) and undercutting. Experiments included sand and loamy sand soil blocks packed at prescribed bulk densities (1.30–1.70 Mg m−3) and with an outflow face at various angles (90°, 75°, and 60°). Constant heads of 15, 25, and 35 cm were imposed on the soil to induce flow. A laser scanner was utilized to obtain the three-dimensional coordinates of the bank and undercut surfaces at approximately 15–30 s intervals. The bulk density of the two different soil types controlled which seepage failure mechanism occurred: (1) tension or “pop-out” failures due to the seepage force exceeding the soil shear strength which was being concurrently reduced by increased soil pore-water pressure, or (2) particle entrainment in the seepage flow, particle mobilization, bank undercutting, and bank collapse when the initial seepage force gradient was less than the resistance of the soil block. For cases experiencing particle mobilization and undercutting, seepage erosion initiated as unimodal (i.e., concentrated at one point) or as multimodal (i.e., initiating at several locations across the bank face), and this result was largely controlled by the bank angle. A five parameter Gaussian function was fitted to the measured three-dimensional undercut shapes to derive parameters for the maximum depth of undercutting, position of the center of the peak, and the vertical and lateral spreads of the undercut. The parameters of this distribution can be useful in the development of improved sediment transport functions and the incorporation of this failure mechanism into hillslope stability models. DA - 2008/9// PY - 2008/9// DO - 10.1016/j.jhydrol.2008.07.005 VL - 359 IS - 3-4 SP - 247-259 J2 - Journal of Hydrology LA - en OP - SN - 0022-1694 UR - http://dx.doi.org/10.1016/j.jhydrol.2008.07.005 DB - Crossref KW - hillslope KW - seepage KW - seepage erosion KW - stability KW - streambank KW - undercutting ER - TY - CONF TI - The role of drainage system and macropore interconnectivity in soil pathogen transport AU - Guzmán, J.A. AU - Fox, G. C2 - 2008/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2008, ASABE 2008 DA - 2008/// VL - 3 SP - 1689-1700 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-63049133110&partnerID=MN8TOARS ER - TY - CONF TI - Subsurface transport of phosphorus in riparian floodplains: Tracer and phosphorus transport experiments AU - Fuchs, J.W. AU - Fox, G. AU - Storm, D. AU - Penn, C. AU - Brown, G. C2 - 2008/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2008, ASABE 2008 DA - 2008/// VL - 9 SP - 5741-5752 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-63049103369&partnerID=MN8TOARS ER - TY - CONF TI - Slope Failure Mechanisms due to Seepage: Three-Dimensional Soil Block Experiments AU - Chu-Agor, M.L. AU - Cancienne, R.M. AU - Fox, G.A. AU - Wilson, G. C2 - 2008/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2008, ASABE 2008 DA - 2008/// VL - 3 SP - 1701-1713 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-63049120190&partnerID=MN8TOARS ER - TY - CONF TI - Seepage erosion mechanisms of bank collapse: Three-dimensional seepage particle mobilization and undercutting AU - Fox, G.A. AU - Chu-Agor, M.L. AU - Cancienne, R.M. AU - Wilson, G.V. AB - Seepage flow initiates undercutting, similar to development and headward migration of internal gullies, by liquefaction of soil particles, followed by mass wasting of the bank. Although seepage erosion has three-dimensional characteristics, two-dimensional lysimeters have been used in previous research to analyze for the hydraulic and geotechnical controls on this mechanism of hillslope, gully, and bank instability. A 50 cm cubic soil block with a focused inflow reservoir was constructed to investigate the mechanisms of seepage erosion and the three-dimensional nature of seepage undercutting. Experiments included 25-cm tall, sand and loamy sand soil blocks packed at prescribed bulk densities (1.30 to 1.70 g cm–3) and with an outflow face at various angles (90, 75, and 60 degrees). Constant heads of 15 cm, 25 cm, and 35 cm were imposed on the soil to induce flow. A laser scanner was utilized to obtain the three-dimensional coordinates of the bank and undercut surfaces at 15 to 30 s intervals. The bulk density for the two different soil types controlled which seepage failure mechanism occurred: (1) tension or "pop-out" failures due to the seepage force exceeding the soil shear strength, or (2) particle entrainment in the seepage flow, particle mobilization, bank undercutting, and bank collapse when the seepage force gradient was initially less than the initial resistance force of the soil block. For cases experiencing particle mobilization and undercutting, seepage erosion initiated as unimodal (i.e., concentrated at one point) or as multimodal (i.e., initiating at several locations across the bank face), largely controlled by the bank angle. As a first approximation, a three-dimensional, five-parameter Gaussian distribution was fit to the undercut shapes to derive parameters for the maximum depth of undercutting, position of the center of the peak, and the vertical and lateral spreads of the undercut. C2 - 2008/// C3 - World Environmental and Water Resources Congress 2008: Ahupua'a - Proceedings of the World Environmental and Water Resources Congress 2008 DA - 2008/// DO - 10.1061/40976(316)292 VL - 316 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-79251522194&partnerID=MN8TOARS ER - TY - JOUR TI - Using MODFLOW to Compare Management Alternatives for a River Alluvial Aquifer AU - Mittelstet, Aaron R AU - Smolen, Michael D AU - Fox, Garey A T2 - 2009 Reno, Nevada, June 21 - June 24, 2009 AB - The ground water policies of Oklahoma and the Texas Panhandle Groundwater Conservation District (GCD) were compared to determine their effects on sustainability of an alluvial aquifer. The Oklahoma policy permits each well to withdraw water at a rate projected to allow not more than 50% of wells to go dry in 20 years. The GCD policy permits pumping at a rate that will consume no more than 50% of the water in 50 years, with reevaluation and readjustment of permits every five years. MODFLOW (Harbaugh and McDonald, 1996) simulations showed that at low development, Oklahoma's policy will limit the pumping rate more than the GCD policy. As development exceeds 65% of the area, more than half of aquifer storage will be depleted. The reevaluation required by the GCD policy will not permit aquifer storage to decline below 50%. Both Oklahoma and GCD policy will reduce baseflow of the river when development exceeds approximately 10%. DA - 2008/// PY - 2008/// DO - 10.13031/2013.27228 ER - TY - JOUR TI - Subsurface Transport of Phosphorus in Riparian Floodplains: Tracer and Phosphorus Transport Experiments AU - Fuchs, John William AU - Fox, Garey A AU - Storm, Dan AU - Penn, Chad AU - Brown, Glenn O T2 - 2008 Providence, Rhode Island, June 29 - July 2, 2008 AB - The primary transport mechanism for phosphorus (P) movement from upland areas to surface water systems is typically surface runoff, with subsurface transport assumed negligible. However, certain local conditions can lead to an environment where subsurface transport may be significant. The objective of this research was to determine the importance of subsurface transport of P along streams characterized by cherty or gravel subsoils. At a field site adjacent to the Barren Fork Creek, a trench was installed with the bottom of the trench at the topsoil/alluvial gravel interface. Fifteen piezometers were installed at various locations surrounding the trench in order to monitor flow and transport. In three separate experiments, water was pumped into the trench from the Barren Fork Creek to maintain a constant head. At the same time, a conservative tracer (Rhodamine WT) and/or potassium phosphate were injected into the trench at concentrations ranging between 3 and 100 ppm for Rhodamine WT and at 100 ppm for P. Rhodamine WT and P were detected in some piezometers at equivalent concentrations as measured in the trench, suggesting the presence of preferential flow pathways. Phosphorus sorption was minimal along the preferential flow pathways but transport was retarded in non-preferential flow paths. DA - 2008/// PY - 2008/// DO - 10.13031/2013.24706 ER - TY - JOUR TI - Slope Failure Mechanisms due to Seepage: Three-Dimensional Soil Block Experiments AU - Chu-Agor, Maria AU - Cancienne, Rachel M AU - Fox, Garey A AU - Wilson, Glenn V T2 - 2008 Providence, Rhode Island, June 29 - July 2, 2008 AB - Seepage erosion has been suggested to potentially play an important role in streambank failure and gully formation. However, although seepage erosion has three-dimensional characteristics, two-dimensional lysimeters were used in previous research to analyze for the hydraulic and geotechnical controls on this mechanism of instability. In this research, a three-dimensional soil block (50 cm by 50 cm by 50 cm with an inflow reservoir capable of generating water heads of 50 cm) was constructed to investigate the three-dimensional nature of seepage undercutting and to derive an improved sediment transport function. Two different soil types (sand and loamy sand) were utilized in these three-dimensional experiments with varying water inflow reservoir heads (15 cm, 25 cm, and 35 cm). Each soil type was packed at various bulk densities (1300, 1450 and 1600 kg/m3 for the sand and 1300, 1450, 1600 and 1700 kg/m3 for the loamy sand) to create a 25 cm tall bank. The bottom of the soil block was lined with densely packed clay to a height of 2.5 cm to serve as a restrictive layer and the rest of the block was packed with soil to the desired bulk density in 2.5 cm lifts. The soil was then cut to simulate various bank angles (90o, 75o, and 60o) such that the horizontal centerline for each bank remained 20 cm away from the water inlet. As water flowed through the column, a three-dimensional laser scanner was utilized to obtain the volume of the eroded bank at approximately 15 to 30 s intervals.The hydraulic conditions producing different seepage failure mechanisms were evaluated and the three-dimensional nature of seepage erosion was investigated. Information from these three-dimensional experiments can be used in a stability model for incorporating seepage undercutting as a failure mechanism. DA - 2008/// PY - 2008/// DO - 10.13031/2013.24952 ER - TY - JOUR TI - The Role of Drainage System and Macropore Interconnectivity in Soil Pathogen Transport AU - Guzmán, Jorge A AU - Fox, Garey A T2 - 2008 Providence, Rhode Island, June 29 - July 2, 2008 AB - The primary transport of pathogenic microorganisms in soils occurs through macropores that bypass the filtering and adsorptive effects of the soil. Recent research indicates immediate breakthrough of solutes and contaminants in subsurface drainage by extraordinarily efficient transport through directly connected macropores. In this study, an innovative soil column packed with loamy sand soil was used to simulate the transport of E. coli through directly connected macropore into the subsurface drainage systems. Four experiments simulating open surface connected and buried macropores were performed. The soil column was flushed with distilled water, diluted swine manure, and finally with distilled water at 0, 48, and 96 hours, respectively, after packing. Both open surface connected and buried macropores were capable of transporting E. coli to the subsurface drain. During the manure flushing, breakthrough time in both discharge and E. coli was inversely proportional to the macropore length. In the macropore, E. coli detection occurred simultaneously with macropore discharge breakthrough. For open surface connected macropores that extended the entire distance between the soil surface and drain except for the last 10 to 20 cm, the maximum E. coli concentrations in the drain flow was approximately 20 to 30% of the inflow E. coli concentration. For buried macropores, maximum E. coli concentrations in the drain flow were approximately 10% of the initial concentration but 25 to 40% in the macropore. The highest E. coli recovery concentrations occurred during the final distilled water flush, approximately 48 hours after manure application. It was hypothesized that these peak concentrations were due to the development of an E. coli pool within the capillary fringe. The findings of this study stress the importance of directly connected macropores to subsurface drainage systems in allowing E. coli to bypass the soil filter capacity, especially after rainfall events or irrigation following manure application. DA - 2008/// PY - 2008/// DO - 10.13031/2013.24951 ER - TY - JOUR TI - Hyporheic and total transient storage in small, sand-bed streams AU - Stofleth, John M. AU - Shields Jr, F. Douglas AU - Fox, Garey A. T2 - Hydrological Processes AB - Abstract Key processes in stream ecosystems are linked to hydraulic retention, which is the departure of stream flow from ideal ‘plug flow’, and reflects fluid movement through surface and hyporheic storage zones. Most existing information about hyporheic exchange is based on flume studies or field measurements in relatively steep streams with beds coarser than sand. Stream tracer studies may be used to quantify overall hydraulic retention, but disaggregation of surface and hyporheic retention remains difficult. A stream tracer approach was used to compute the rates at which stream water is exchanged with water in storage zones (total storage) in short reaches of two small, sand‐bed streams under free and obstructed flow conditions. Tracer curves were fit to the one‐dimensional transport with inflow storage model OTIS‐P. Networks of piezometers were used to measure specific discharge between the stream and the groundwater. In the sand‐bed streams studied, parameters describing total retention were in the upper 50% of data compiled from the literature, most of which represented streams with beds coarser than sand. However, hyporheic storage was an insignificant component of total hydraulic retention, representing only 0·01–0·49% of total exchange, and this fraction did not increase after installation of flow obstructions. Total retention did not vary systematically with bed material size, but increased 50–100% following flow obstruction. Removal of roughness elements, such as large wood and debris dams, is detrimental to processes dependent upon transient storage in small, sand‐bed streams. Copyright © 2007 John Wiley & Sons, Ltd. DA - 2008/// PY - 2008/// DO - 10.1002/hyp.6773 VL - 22 IS - 12 SP - 1885-1894 J2 - Hydrol. Process. LA - en OP - SN - 0885-6087 1099-1085 UR - http://dx.doi.org/10.1002/hyp.6773 DB - Crossref KW - hydraulic retention KW - streams KW - sand KW - hyporheic zones KW - tracers KW - large wood KW - piezometers KW - transport ER - TY - JOUR TI - Estimating Watershed Level Nonagricultural Pesticide Use From Golf Courses Using Geospatial Methods AU - Fox, Garey A. AU - Thelin, Gail P. AU - Sabbagh, George J. AU - Fuchs, John W. AU - Kelly, Iain D. T2 - JAWRA Journal of the American Water Resources Association AB - Abstract: Limited information exists on pesticide use for nonagricultural purposes, making it difficult to estimate pesticide loadings from nonagricultural sources to surface water and to conduct environmental risk assessments. A method was developed to estimate the amount of pesticide use on recreational turf grasses, specifically golf course turf grasses, for watersheds located throughout the conterminous United States (U.S.). The approach estimates pesticide use: (1) based on the area of recreational turf grasses (used as a surrogate for turf associated with golf courses) within the watershed, which was derived from maps of land cover, and (2) from data on the location and average treatable area of golf courses. The area of golf course turf grasses determined from these two methods was used to calculate the percentage of each watershed planted in golf course turf grass (percent crop area, or PCA). Turf‐grass PCAs derived from the two methods were used with recommended application rates provided on pesticide labels to estimate total pesticide use on recreational turf within 1,606 watersheds associated with surface‐water sources of drinking water. These pesticide use estimates made from label rates and PCAs were compared to use estimates from industry sales data on the amount of each pesticide sold for use within the watershed. The PCAs derived from the land‐cover data had an average value of 0.4% of a watershed with minimum of 0.01% and a maximum of 9.8%, whereas the PCA values that are based on the number of golf courses in a watershed had an average of 0.3% of a watershed with a minimum of <0.01% and a maximum of 14.2%. Both the land‐cover method and the number of golf courses method produced similar PCA distributions, suggesting that either technique may be used to provide a PCA estimate for recreational turf. The average and maximum PCAs generally correlated to watershed size, with the highest PCAs estimated for small watersheds. Using watershed specific PCAs, combined with label rates, resulted in greater than two orders of magnitude over‐estimation of the pesticide use compared to estimates from sales data. DA - 2008/12// PY - 2008/12// DO - 10.1111/j.1752-1688.2008.00229.x VL - 44 IS - 6 SP - 1363–1372 SN - 1093-474X 1752-1688 UR - http://dx.doi.org/10.1111/j.1752-1688.2008.00229.x KW - geospatial analysis KW - risk assessment KW - watersheds KW - pesticides KW - geospatial data KW - golf course KW - nonagricultural pesticide KW - percent crop area KW - percent crop area estimation KW - recreational turf KW - use estimate ER - TY - JOUR TI - Numerical modeling of bank instability by seepage erosion undercutting of layered streambanks AU - Chu-Agor, M.L. AU - Wilson, G.V. AU - Fox, G.A. T2 - Journal of Hydrologic Engineering AB - Undercutting, primarily considered due to fluvial mechanisms, has been reported to have a major impact on slope failure. Predicting bank collapse specifically due to seepage erosion undercutting by particle mobilization on layered streambanks has not been fully studied or modeled, even though its role in streambank erosion may be important. The limitation originates from the limited field measurements or laboratory experiments as well as the unavailability of discrete element models that can effectively simulate seepage particle mobilization, undercutting, and the corresponding mass wasting. The objective of this research was to demonstrate a procedure for incorporating seepage undercutting into bank stability models and to investigate the role of seepage undercutting on bank instability. The question to be addressed is whether seepage particle mobilization can lead to distances of undercutting that are a significant cause of bank instability. A numerical finite-element model, SEEP/W, was used to model soil-water pressure variations during seepage observed in laboratory experiments with two-dimensional soil lysimeters. Flow parameters were calibrated using measured soil-water pressure and cumulative discharge. A general limit equilibrium bank stability model (SLOPE/W) was used to simulate bank stability with and without seepage erosion undercutting by comparing the computed factor of safety, Fs, at different stages of the seepage erosion process with regard to input parameter uncertainty using Monte Carlo analysis. The percentage decrease in the mean Fs ranged between 42 and 91% as the depth of undercutting increased, dependent upon the initial stability of the bank. A stable bank (i.e., Fs>1) can quickly become unstable (i.e., Fs<1) when seepage undercutting is considered. For stable banks, the probability of failure reached 100% when the depth of the undercutting reached approximately 30to50mm under these experimental conditions. The results derived are specific to the streambank simulated but are expected to be comparable for similar layered streambank lithologies reported to occur in numerous geographical locations. This research also highlights the need to incorporate the dynamic process of seepage erosion undercutting into integrated subsurface flow and streambank stability models. DA - 2008/// PY - 2008/// DO - 10.1061/(ASCE)1084-0699(2008)13:12(1133) VL - 13 IS - 12 SP - 1133-1145 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-56449106433&partnerID=MN8TOARS ER - TY - JOUR TI - Numerical Simulation of Flow Dynamics during Macropore-Subsurface Drain Interactions Using HYDRUS AU - Akay, Onur AU - Fox, Garey A. AU - Šimůnek, Jirka T2 - Vadose Zone Journal AB - Macropores, such as those created by deep‐burrowing earthworms, have the potential to be hydraulically connected not only to the soil surface but also to subsurface drains. This hydraulic connection may lead to rapid movement of surface‐applied chemicals to receiving waters as they bypass the bulk of the soil matrix. In this study, a numerical model (HYDRUS) that solves the three‐dimensional Richards equation for both matrix and macropore domains was used to analyze previously conducted experiments that contained a single, surface‐connected or buried, artificial macropore and a subsurface drain installed in a laboratory soil column. Both matrix and macropore domains were parameterized using continuous soil hydraulic functions. Simulations confirmed that surface‐connected macropores were highly efficient preferential flow paths that substantially reduced arrival times to the subsurface drainage outlet, with this reduction being directly related to the length of the macropore. Surface‐connected macropores need to extend at least halfway to the drain to have a noticeable effect (>50% reduction) on the arrival time. No significant changes were observed in total drain outflows for columns with laterally shifted macropores (away from a drain) compared with centered macropores unless the macropore depth extended significantly (>75%) into the profile. The model predicted that buried macropores became active and contributed to the total outflow only when pressure heads in the soil profile became positive. The effect of buried macropores on drain flow was investigated for a case where an initially partially saturated profile was drained. Under these conditions, the numerical simulations suggested that buried macropores could contribute up to 40% of the total outflow, which confirms laboratory observations with subsurface‐drained soil columns with macropores. DA - 2008/8// PY - 2008/8// DO - 10.2136/vzj2007.0148 VL - 7 IS - 3 SP - 909-918 J2 - Vadose Zone Journal LA - en OP - SN - 1539-1663 UR - http://dx.doi.org/10.2136/vzj2007.0148 DB - Crossref ER - TY - JOUR TI - Influence of seepage undercutting on the stability of root-reinforced streambanks AU - Cancienne, Rachel M. AU - Fox, Garey A. AU - Simon, Andrew T2 - Earth Surface Processes and Landforms AB - Abstract Several mechanisms contribute to streambank failure including fluvial toe undercutting, reduced soil shear strength by increased soil pore‐water pressure, and seepage erosion. Recent research has suggested that seepage erosion of noncohesive soil layers undercutting the banks may play an equivalent role in streambank failure to increased soil pore‐water pressure. However, this past research has primarily been limited to laboratory studies of non‐vegetated banks. The objective of this research was to utilize the Bank Stability and Toe Erosion Model (BSTEM) in order to determine the importance of seepage undercutting relative to bank shear strength, bank angle, soil pore‐water pressure, and root reinforcement. The BSTEM simulated two streambanks: Little Topashaw Creek and Goodwin Creek in northern Mississippi. Simulations included three bank angles (70° to 90°), four pore‐water pressure distributions (unsaturated, two partially saturated cases, and fully saturated), six distances of undercutting (0 to 40 cm), and 13 different vegetation conditions (root cohesions from 0·0 to 15·0 kPa). A relative sensitivity analysis suggested that BSTEM was approximately three to four times more sensitive to water table position than root cohesion or depth of seepage undercutting. Seepage undercutting becomes a prominent bank failure mechanism on unsaturated to partially saturated streambanks with root reinforcement, even with undercutting distances as small as 20 cm. Consideration of seepage undercutting is less important under conditions of partially to fully saturated soil pore‐water conditions. The distance at which instability by undercutting became equivalent to instability by increased soil pore‐water pressure decreased as root reinforcement increased, with values typically ranging between 20 and 40 cm at Little Topashaw Creek and between 20 and 55 cm at Goodwin Creek. This research depicts the baseline conditions at which seepage undercutting of vegetated streambanks needs to be considered for bank stability analyses. Copyright © 2008 John Wiley & Sons, Ltd. DA - 2008/10/15/ PY - 2008/10/15/ DO - 10.1002/esp.1657 VL - 33 IS - 11 SP - 1769-1786 J2 - Earth Surf. Process. Landforms LA - en OP - SN - 0197-9337 1096-9837 UR - http://dx.doi.org/10.1002/esp.1657 DB - Crossref ER - TY - CONF TI - E. coli fate and transport in macroporous soils: Short-circuiting to the subsurface AU - Fox, G.A. AU - Kanwar, R. AU - Guzman, J. AU - Hoang, C.K. AU - Malone, R.W. AU - Moorman, T. AU - Pederson, C. AB - Pathogen concentrations in streamflow are commonly reported as a significant cause of water quality degradation throughout the world. Research has begun to attempt to model pathogen fate and transport, primarily through surface runoff mechanisms. A significant component of pathogen movement to streams commonly identified but not explicitly simulated in many models is pathogen movement to the subsurface, which can be important in several scenarios such as tile drainage systems. As colloidal contaminants, pathogens such as E. coli tend to become physically trapped in the soil matrix but can move quickly through soil macropores. In fact, concerns exist about the rapid transport of contaminants, such as pesticides, pathogens, and nutrients, from the soil surface to ground water through macropores. Recent research suggests short-circuiting or direct hydrologic connectivity between macropores and subsurface drains. The objective of this paper is to provide an overview of the current research regarding the fate and transport of E. coli through soil macropores and into subsurface drain systems. This paper reports early results from the first year of a multi-year study funded by the USDA Cooperative State Research, Education, and Extension Service as part of the their National Research Initiative program. Field experiments to document short-circuiting by macropores are described and also laboratory data is presented from soil column experiments, capable of simulating surface-connected macropores, with artificial subsurface drainage boundary conditions. These column studies generated information regarding the importance of directly connected macropores on pathogen transport to subsurface drains. C2 - 2008/// C3 - World Environmental and Water Resources Congress 2008: Ahupua'a - Proceedings of the World Environmental and Water Resources Congress 2008 DA - 2008/// DO - 10.1061/40976(316)32 VL - 316 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-79251529167&partnerID=MN8TOARS ER - TY - CONF TI - Laboratory experiments on three-dimensional seepage erosion undercutting of vegetated banks AU - Cancienne, R.M. AU - Fox, G.A. C2 - 2008/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2008, ASABE 2008 DA - 2008/// VL - 6 SP - 3550-3561 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-63049094259&partnerID=MN8TOARS ER - TY - JOUR TI - Laboratory Experiments on Three-Dimensional Seepage Erosion Undercutting of Vegetated Banks AU - Cancienne, Rachel M AU - Fox, Garey A T2 - 2008 Providence, Rhode Island, June 29 - July 2, 2008 AB - Root reinforcement plays a prominent role in streambank stability. Considerable work has analyzed the effects of in situ root reinforcement on soil shear strength. However, the number of controlled studies to quantify root reinforcement with specific instability mechanisms, especially seepage, is limited. Four 50 cm cubic soil blocks, each with a focused inflow reservoir, were constructed to investigate the effects of vegetation on seepage erosion and streambank stability. Experiments included 25-cm tall, 90o loamy sand banks packed at 1.6 g cm-3 bulk densities. A constant head of 25 cm was imposed on the soil to induce flow. Switchgrass (Panicum virgatum) was planted on top of three of the four soil blocks (one as control with bare soil) and was allowed a two-month growth period inside a greenhouse. A laser scanner was utilized to obtain the three-dimensional coordinates of the bank and undercut surfaces at approximately 15 to 30 s intervals. The stressed state of the vegetation yielded lower root reinforcement values (6.2 to 12.4 kPa) than in situ field measurements (i.e. 18 kPa). Soil blocks with greater root reinforcement experienced longer times to bank failure, up to a certain limit, than their counterparts with lower root cohesion values. Separate stability analyses incorporating (1) seepage erosion undercutting and (2) seepage erosion forces confirmed the need for a conglomerate model with both destabilizing mechanisms for streambank stability predictions. DA - 2008/// PY - 2008/// DO - 10.13031/2013.25035 ER - TY - JOUR TI - Earthworms and E. coli AU - Fox, G.A. AU - Kanwar, R. AU - Malone, R. T2 - Resource: Engineering and Technology for Sustainable World DA - 2008/// PY - 2008/// VL - 15 IS - 6 SP - 22-24 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-55649102970&partnerID=MN8TOARS ER - TY - JOUR TI - Comparison of three techniques for determining ammonia emission fluxes from broiler litter AU - Liu, Z. AU - Wang, L. AU - Beasley, D.B. T2 - Transactions of the ASABE DA - 2008/// PY - 2008/// VL - 51 IS - 5 SP - 1783-1790 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-55249113187&partnerID=MN8TOARS ER - TY - JOUR TI - Identification of quantitative trait loci for resistance to southern leaf blight and days to anthesis in two maize recombinant inbred line populations AU - Balint-Kurti, P.J. AU - Zwonitzer, J.C. AU - Pè, M.E. AU - Pea, G. AU - Lee, M. AU - Cardinal, A.J. T2 - Phytopathology AB - The genetic architecture underlying resistance in maize to southern leaf blight (SLB) caused by Cochliobolus heterostrophus race O is not well understood. The objective of this study was to identify loci contributing to SLB resistance in two recombinant inbred line populations and to compare these to SLB resistance loci in other populations. The two populations used were derived from crosses between maize inbred lines H99 and B73 (HB population–142 lines) and between B73 and B52 (BB population–186 lines). They were evaluated for SLB resistance and for days from planting to anthesis (DTA) in 2005 and 2006. Two replications arranged as randomized complete blocks were assessed in each year for each population. Entry mean heritabilities for disease resistance were high for both populations (0.876 and 0.761, respectively). Quantitative trait loci (QTL) for SLB resistance were identified in bins 3.04 (two QTL), 6.01, and 8.05 in the HB population and in bin 2.07 in the BB population. No overlap of DTA and SLB resistance QTL was observed, nor was there any phenotypic correlation between the traits. A comparison of the results of all published SLB resistance QTL studies suggested that bins 3.04 and 6.01 are ‘hotspots’ for SLB resistance QTL. DA - 2008/// PY - 2008/// DO - 10.1094/PHYTO-98-3-0315 VL - 98 IS - 3 SP - 315-320 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-40849084152&partnerID=MN8TOARS ER - TY - JOUR TI - IDENTIFYING MAIZE GERMPLASM WITH RESISTANCE TO AFLATOXIN ACCUMULATION AU - Williams, W. AU - Krakowsky, Matthew D. AU - Windham, Gary L. AU - Balint-Kurti, Peter AU - Hawkins, Leigh K. AU - Henry, W. T2 - Toxin Reviews AB - Contamination of maize grain, Zea mays L., with aflatoxin, a toxin produced by the fungus Aspergillus flavus, reduces its value and marketability. Growing hybrids with resistance is generally considered a highly desirable way to reduce A. flavus infection and aflatoxin accumulation. Identifying maize germplasm with resistance is critical to the development and production of such hybrids. USDA-ARS scientists at Mississippi State, Mississippi; Tifton, Georgia; and Raleigh, North Carolina; have engaged in a multilocation approach to germplasm screening. A major component of this has been the evaluation of accessions obtained from the Germplasm Enhancement of Maize (GEM) project at both Mississippi State and Tifton. Selections from GEM accessions 250_01_XL370A_S11_F2S4_9214_Blk21/00-# and 2250_02_XL370A_S11_F2S4_3363_Blk03/00-# exhibited the highest levels of resistance both as lines per se and in testcrosses. Lines developed at the International Maize and Wheat Improvement Center (CIMMYT) and North Carolina ... DA - 2008/1// PY - 2008/1// DO - 10.1080/15569540802399838 VL - 27 IS - 3-4 SP - 319-345 KW - aflatoxin KW - Aspergillus flavus KW - maize KW - plant resistance KW - Zea mays ER - TY - JOUR TI - Mining and Harnessing Natural Variation: A Little MAGIC AU - Johal, Gurmukh S. AU - Balint-Kurti, Peter AU - Weil, Clifford F. T2 - Crop Science AB - The success of a breeding program depends on having adequate diversity in the germplasm. However, as advanced breeding stocks and materials are generated, one casualty is the diversity itself. As a result, breeding programs in many crop species have reached a point of diminishing returns and it is feared that unless new diversity is infused into the breeding germplasm, we face catastrophic reductions in crop productivity if the climate turns adverse. Although some scientists favor transgenic approaches, a “back to nature” approach to genetic diversity may prove faster and more effective. Wild and exotic relatives of crop plants hold a wealth of alleles that, if we can find them, can help break yield barriers and enhance tolerance to stresses. Many approaches, based largely on quantitative trait loci genetics, have been proposed and used for this purpose, but most are either highly laborious or discover relevant variation inefficiently. Here, we propose a gene‐centered approach, dubbed MAGIC ( m utant‐ a ssisted g ene i dentification and c haracterization), that uses Mendelian mutants or other genetic variants in a trait of interest as reporters to identify novel genes and variants for that trait. MAGIC is similar to enhancer–suppressor screens, but rather than relying on variation created in the laboratory, it reveals variation created and refined by nature over millions of years of evolution. This approach could be an effective tool for exploring novel variation and a valuable means to harness natural diversity and define genetic networks. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2008.03.0150 VL - 48 IS - 6 SP - 2066 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-57149091739&partnerID=MN8TOARS ER - TY - JOUR TI - Effect of vegetation management on bird habitat in Riparian buffer zones AU - Smith, Timothy A. AU - Osmond, Deanna L. AU - Moorman, Christopher E. AU - Stucky, Jon M. AU - Gilliam, J. Wendell T2 - SOUTHEASTERN NATURALIST AB - Riparian buffers can be valuable refuge areas for wildlife in otherwise homogeneous agricultural landscapes. Government sponsored programs like the Cropland Reserve Program generally require the planting of specific vegetative species during buffer restoration, although the effectiveness of such an approach when compared to restoration by volunteer species is unknown. We studied the effect of differences in vegetation structure on avian habitat in riparian buffer zones. A 25 m (82 ft) wide planted woodland buffer, 30 m (98 ft) wide grass, shrub, and woodland three-zone buffer, and a 9 m (30 ft) wide shrub buffer were evaluated for habitat potential using breeding-bird counts and vegetation surveys. Bird density and species richness varied with the structure of the vegetative communities present at the three sites. Avian species richness and total detections were higher in the three-zone buffer than in both the shrub and planted buffer, likely a result of the diversity of vegetation at the site. These data suggest that restoration of riparian areas by allowing fallow vegetation to recolonize is at the very least equally beneficial to avian wildlife as is restoration by planting specific grass, shrub, and tree species. Buffer restoration by natural revegetation using this method could be recommended as an alternative to implementation by planting riparian species due to its simplicity and cost effectiveness. DA - 2008/// PY - 2008/// DO - 10.1656/1528-7092(2008)7[277:EOVMOB]2.0.CO;2 VL - 7 IS - 2 SP - 277-288 SN - 1938-5412 ER - TY - BOOK TI - Vermicomposting leader's guide: A 5th grade school enrichment curriculum AU - Sherman, R. AU - Liverman, R. AU - Maxa, E. DA - 2008/// PY - 2008/// PB - Raleigh, NC: Cooperative Extension Service ER - TY - CONF TI - Modeling of microwave based chemical pretreatment of switchgrass AU - Keshwani, D. R. AU - Cheng, J. J. C2 - 2008/// C3 - Proceedings of the ASABE Annual International Meeting (Providence, Rhode Island) DA - 2008/// VL - 083954 ER - TY - CONF TI - Lime pretreatment of switchgrass for bioethanol production AU - Xu, J. AU - Cheng, Jay AU - Sharma-Shivappa, R. R. AU - Burns, J. C. AB - Lignocellulose-to-ethanol conversion is a promising technology to supplement corn-based ethanol production. To improve the enzymatic digestibility of lignocellulosic materials, pretreatment is necessary as it alters the structure of lignocellulosic matrix, thereby making the cellulose more accessible to cellulase enzymes during hydrolysis. In this research, switchgrass was used as lignocellulosic feedstock and lime was used as pretreatment agent to study the impact of lime loading, residence time and temperature on the reducing sugar yield of biomass after pretreatment. The results showed that lime pretreatment could effectively improve the digestibility of switchgrass at both high temperature and low temperature. At 121oC, increasing lime loading or extending residence time didnt necessarily favor the improvement of biomass digestibility. 15 min pretreatment with the lime loading of 0.10 g/g raw biomass was recommended. At 50oC, longer residence times were needed while the lime requirement didnt change. 24 h pretreatment with the lime loading of 0.10 g/g raw biomass was recommended. Using the recommended conditions, the reducing sugar yields of pretreated biomass were over 4 times that of unpretreated biomass. The research also showed that lime pretreatment was promising at even lower temperatures. At ambient temperature, the total reducing sugar yield from raw biomass reached 392 mg/g raw biomass after 24 h lime pretreatment, only 8% lower than that obtained under the recommended condition at 121oC or 50oC. C2 - 2008/// C3 - Proceedings of the ASABE Annual International Meeting (Providence, Rhode Island) DA - 2008/// DO - 10.13031/2013.24815 VL - 083998 ER - TY - CONF TI - Hydrolysis and fermentation of new switchgrass germplasm for bioethanol production AU - Yang, Y. AU - Sharma, R. R. AU - Burns, J. C. AU - Cheng, J. J. C2 - 2008/// C3 - Proceedings of the ASABE Annual International Meeting (Providence, Rhode Island) DA - 2008/// VL - 083799 ER - TY - CONF TI - High temperature dilute acid pretreatment of coastal bermudagrass AU - Redding, A. P. AU - Wang, Z. AU - Keshwani, D. R. AU - Cheng, Jay AB - The conversion of lignocellulosic biomass into ethanol is an encouraging technology in the face of concerns over global warming and finite energy resources. In the southeastern United States, coastal bermudagrass shows potential for use as an energy crop for ethanol production. A review of the literature has shown that research has been done on the dilute sulfuric acid pretreatment of costal bermudagrass at 121C prior to enzymatic hydrolysis. This study examined dilute acid concentrations of 0.3%(w/w) to 1.2%(w/w) at temperatures from 120C to 180C over residence times of 5 to 60 minutes in an effort to optimize the pretreatment process for sugar production. Bermudagrass was pretreated in a 1:10 mixture with dilute sulfuric acid. The pretreated solids were enzymatically hydrolyzed and the resulting reducing sugars have been quantified using a DNS assay method. Data is still being generated,, but from average total reducing sugar data that has been analyzed, the pretreatment conditions of 1.2% sulfuric acid (w/w) for 30 minutes yields optimum sugar production of 300 mg sugars / gram of un-pretreated biomass. Carbohydrate and lignin content will be measured before and after pretreatment in addition to an estimation of reducing sugars in the pretreatment filtrate in future work. C2 - 2008/// C3 - Proceedings of the ASABE Annual International Meeting (Providence, Rhode Island) DA - 2008/// DO - 10.13031/2013.25041 VL - 084148 ER - TY - CONF TI - Alkaline pretreatment of switchgrass for ethanol production AU - Xu, J. AU - Cheng, J. J. C2 - 2008/// C3 - IBE Annual Meeting (Chapel Hill, North Carolina) DA - 2008/// ER - TY - CONF TI - Alkaline pretreatment of coastal bermudagrass for bioethanol production AU - Wang, Z. AU - Keshwani, D. R. AU - Redding, A. P. AU - Cheng, J. J. C2 - 2008/// C3 - Proceedings of the ASABBE Annual International Meeting (Providence, Rhode Island) DA - 2008/// VL - 084013 ER - TY - JOUR TI - conversion of cotton wastes to bioenergy and value-added products AU - Sharma-Shivappa, R. R. AU - Chen, Y. T2 - Transactions of the ASABE AB - Cotton accounts for nearly 40% of global fiber production. While approximately 80 countries worldwide produce cotton, the U.S., China, and India together provide over half the world's cotton. High cotton production is accompanied by generation of tons of cotton waste each year. Large amounts of residue from the field and gins results in not only environmental problems due to disposal issues and cotton diseases and pests, but also difficulties in cultivation due to slow decomposition in the soil. Development of economical and efficient methods for utilizing and/or disposing of cotton waste have been investigated for years, but scale-up and marketing issues need to be resolved. Cotton waste can be used as an energy source through briquetting, pyrolysis, and anaerobic digestion. Studies suggest that composition of cotton waste is similar to other lignocellulosic feedstocks, and it has the potential to be used for bioethanol production. However, proper pretreatment strategies need to be developed to reduce lignin (comprising approximately 30%). Cotton waste can also be processed into industrial products such as animal feed and bedding, soil amendment, and substrate for vegetative growth through various treatments. Enzyme production through utilization of cotton waste as a carbon source is another potential application. A review of the various conversion processes suggests that although cotton waste is suitable for the production of a variety of products, in-depth investigation at the pilot scale is essential to determine process efficacy and economic feasibility. DA - 2008/// PY - 2008/// DO - 10.13031/2013.25377 VL - 51 IS - 6 SP - 2239-2246 ER - TY - JOUR TI - Mining and Harnessing Natural Variation: A Little MAGIC AU - Johal, G. S. AU - Balint-Kurti, P. AU - Well, C. F. T2 - Crop Science DA - 2008/// PY - 2008/// VL - 48 IS - 6 SP - 2066-2073 ER - TY - JOUR TI - Modeling thermal stratification in fan-ventilated greenhouses AU - Li, S. AU - Willits, D. H. T2 - Transactions of the ASABE AB - A two-dimensional thermal model was developed to investigate the thermal stratification in fan-ventilated greenhouses. Model inputs include outside weather (air temperature, humidity, and solar radiation), geometric parameters of crop rows and leaf area index, greenhouse ground and roof temperatures, ventilation rate, and operation of evaporative cooling pads. Comparing predictions with observed data indicated that the air temperature and relative humidity were modeled at acceptable accuracies, with air temperature underpredicted by 1.3C and relative humidity overpredicted by 9%, on average for a planted greenhouse. For an unplanted greenhouse, the air temperature was predicted with an absolute error of 0.7C, while for relative humidity the absolute error was 3%. Vertical temperature variation, defined as maximum temperature minus minimum temperature at approximately the central location of greenhouse, was predicted with an absolute error of 0.1C and a relative absolute error of 10% for the planted greenhouse, while for an unplanted greenhouse it was 0.6C for the absolute error and 12% for the relative absolute error. Simulations with the model suggest that increasing ventilation rate reduced the vertical temperature gradient. Increased ventilation reduced air temperature more at the top than the bottom of the greenhouse. Greater air temperature variation was produced when using evaporative pad cooling than not. Air temperature was reduced more at the bottom than at the top with evaporative pad cooling. The presence of a canopy altered the vertical air temperature distribution and reduced the temperature variation. A sample simulation showed that on a typical summer day at Raleigh, North Carolina, the presence of a canopy row with a height of 1.75 m occupying 69% of the ground area reduced the air temperature variation from 11.5C to 1.8C in a fan-ventilated greenhouse operating with a ventilation rate of 0.087 m3 m-2 s-1 and using evaporative pad cooling. The peak air temperature generally occurred at the top of canopy or somewhat below the canopy top. This finding may have some significance in establishing the location of temperature control sensors in future control systems. DA - 2008/// PY - 2008/// DO - 10.13031/2013.25307 VL - 51 IS - 5 SP - 1735-1746 ER - TY - CONF TI - Comparison of three techniques for determining ammonia emission fluxes from broiler litter AU - Liu, Z. AU - Wang, L. AU - Beasley, D. B. AB - This article reports an experimental study of three techniques in ammonia emission flux determination. Ammonia concentrations in a dynamic flow-through chamber with broiler litter were measured simultaneously by a chemiluminescence ammonia analyzer and an acid scrubber. At the beginning and ending of each test, the litter samples were analyzed for conducting nitrogen mass balance. Ammonia emissions were estimated from the two concentration measurements and the mass balance approach. It was observed that the chemiluminescence analyzer measurements tended to overestimate ammonia concentration compared with the acid scrubber measurements, especially when litter moisture was high. Statistical results indicated that the effect of litter moisture content on the ratios of the average chemiluminescence analyzer measurements over the acid scrubber measurements was significant, and a p-value of 0.0104 was obtained. Great uncertainties were observed for the mass balance approach, especially when the percentages of the total nitrogen losses in litter samples were small (less than 2%). In order to apply the mass balance approach to estimate ammonia emissions and to achieve acceptable accuracy, a substantially long testing period (more than 80 h) is needed under the observed ammonia emission level (104 to 1137 mg N h-1 m-2), and great efforts are needed to reduce the uncertainties associated with sampling and analyzing litter nitrogen content. C2 - 2008/// C3 - Transactions of the ASABE DA - 2008/// DO - 10.13031/2013.25304 VL - 51 SP - 1783-1790 M1 - 5 ER - TY - JOUR TI - Hydrologic comparison of four types of permeable pavement and standard asphalt in eastern North Carolina AU - Collins, K. A. AU - Hunt, W. F. AU - Hathaway, J. M. T2 - Journal of Hydrologic Engineering AB - A permeable pavement parking lot in eastern North Carolina consisting of four types of permeable pavement and standard asphalt was monitored from June 2006 to July 2007 for hydrologic differences in pavement surface runoff volumes, total outflow volumes, peak flow rates, and time to peak. The four permeable sections were pervious concrete (PC), two types of permeable interlocking concrete pavement (PICP) with small-sized aggregate in the joints and having 12.9% (PICP1) and 8.5% (PICP2) open surface area, and concrete grid pavers (CGP) filled with sand. The site was located in poorly drained soils, and all permeable sections were underlain by a crushed stone base layer with a perforated underdrain. All permeable pavements significantly reduced surface runoff volumes and peak flow rates from those of asphalt (p<0.01). Of the permeable pavements, CGP generated the greatest surface runoff volumes (p<0.01). The PICP1 and CGP cells generated significantly lower total outflow volumes than all other sections evaluated (p<0.01), and had the lowest peak flows and the longest time to peak. The response of the PICP1 cell was likely due to an increased base storage volume resulting from an elevated pipe underdrain whereas the CGP cell response was attributed to water retention in the sand fill layer. Overall, different permeable pavement sections performed similarly, but were substantially different from asphalt. Subtle differences in the performance of CGP were primarily due to the characteristics of the sand filled media compared to small aggregate typically used in PC and PICP joints and bedding. DA - 2008/// PY - 2008/// DO - 10.1061/(ASCE)1084-0699(2008)13:12(1146) VL - 13 IS - 12 SP - 1146-1157 ER - TY - JOUR TI - Comparing low-pressure and high-pressure fogging systems in naturally ventilated greenhouses AU - Li, S. AU - Willits, D. H. T2 - BIOSYSTEMS ENGINEERING AB - The cooling performance of a low-pressure (405 kPa working pressure) and a high-pressure fogging system (6.89 MPa) was evaluated. Experiments were conducted in two empty, naturally ventilated greenhouses under summer conditions for a period of about two months. One greenhouse was used as the treatment greenhouse (fogged house) and another was used as the control house (un-fogged house). Cooling efficiency was defined by the ratio of the temperature difference between the un-fogged and fogged greenhouses to the difference between the temperature in un-fogged house and the wet-bulb temperature in the fogged greenhouse. Evaporation efficiency was defined as the ratio of fog evaporation rate to spray rate. Cooling efficiency and evaporation efficiency were compared for the low-pressure and high-pressure systems after accounting for differences in weather conditions under which the two systems were operated. It is suggested that on average evaporation efficiency for the high-pressure system was at least 64% greater than the low-pressure system; cooling efficiency for the high-pressure system was at least 28% greater than for the low-pressure system. DA - 2008/9// PY - 2008/9// DO - 10.1016/j.biosystemseng.2008.06.004 VL - 101 IS - 1 SP - 69-77 SN - 1537-5129 ER - TY - JOUR TI - Use of an advanced intercross line population for precise mapping of quantitative trait loci for gray leaf spot resistance in maize AU - Balint-Kurti, Peter J. AU - Wisser, Randall AU - Zwonitzer, John C. T2 - CROP SCIENCE AB - Gray leaf spot [GLS, causal agent Cercospora zeae‐maydis (Tehon and E. Y. Daniels)] is an important fungal disease of maize in the U.S. and worldwide. The IBM population, an advanced intercross recombinant inbred line population derived from a cross between the maize lines Mo17 (resistant) and B73 (susceptible), was evaluated in three environments (Andrews, NC in 2005, 2006, and 2007) for resistance to GLS and for days from planting to anthesis (DTA). A conventional recombinant inbred line population derived from the same two parents (the “Stuber” population) was also assessed for GLS resistance in two environments (Andrews NC, 2004 and 2005). Quantitative trait loci (QTL) for GLS resistance were detected in each population. Five significant QTL were detected in the IBM population in bins 1.05, 2.04, 4.05, 9.03, and 9.05. In each case the QTL were localized to regions less than 3 centiMorgans (cM). Two QTL for GLS resistance were identified in the Stuber population in bins 2.04 and 7.05. The GLS QTL in bin 2.04 was previously identified as a QTL for southern leaf blight resistance in the IBM population. These results were compared with results from five previous GLS QTL studies and two potential GLS QTL “hotspots” were identified in bins 1.05–1.06 and 2.03–2.05. As expected, QTL were identified with much more precision in the IBM population compared to the Stuber population and to previous studies. There was no significant correlation between disease resistance and days to anthesis. Three DTA QTL were detected in bins 4.09, 8.05, and 9.02, which did not co‐localize with GLS QTL. DA - 2008/// PY - 2008/// DO - 10.2135/cropsci2007.12.0679 VL - 48 IS - 5 SP - 1696-1704 SN - 1435-0653 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-54949084231&partnerID=MN8TOARS ER - TY - CONF TI - Nitrogen balance for a plantation forest drainage canal on the North Carolina coastal plain AU - Appelboom, T. W. AU - Chescheir, G. M. AU - Skaggs, R. W. AU - Gilliam, J. W. AU - Amatya, D. M. AB - Human alteration of the nitrogen cycle has led to increased riverine nitrogen loads, contributing to the eutrophication of lakes, streams, estuaries, and near-coastal oceans. These riverine nitrogen loads are usually less than the total nitrogen inputs to the system, indicating nitrogen removal during transport through the drainage network. A two-year monitoring study quantified the ammonium, nitrate, and organic-N inputs, outputs, and inferred in-stream processes responsible for nitrogen transformations and removal in a 1900 m reach of a drainage canal located in a managed pine plantation. Total nitrogen inputs to the canal section were 527.8 kg in 2001 and 1422.7 kg in 2002. Total nitrogen discharge at the outlet was 502 kg in 2001 and 1458 kg in 2002. The mass balance of nitrogen inputs and outputs indicated a loss of 25.8 kg (5.1%) of total nitrogen from the system in 2001, and a gain of 35.3 kg (2.4%) of total nitrogen to the system in 2002. Variability in the input and output estimates was high, especially for groundwater exchange. Different hydrologic and nitrogen inputs and outputs were identified and quantified, but measurement variability obscured any potential nitrogen removal from the system. C2 - 2008/// C3 - Transactions of the ASABE DA - 2008/// DO - 10.13031/2013.25239 VL - 51 SP - 1215-1233 M1 - 4 ER - TY - JOUR TI - An experimental evaluation of thermal stratification in a fan-ventilated greenhouse AU - Li, S. AU - Willits, D. H. T2 - Transactions of the ASABE AB - Experiments were performed to investigate air velocity and vertical air temperature distributions in a fan-ventilated greenhouse. The effects of ventilation rate and canopy size on the allocation of airflow between canopy and non-canopy areas were examined. The data suggested that the ratio of the air velocity within the canopy to the mean velocity of the entire greenhouse cross-section depended on not only the area ratio of canopy to greenhouse cross-section, but also ventilation rate. The ratio of canopy air velocity to greenhouse average velocity decreased if ventilation rate increased. The effects of outside solar radiation, ventilation rate, evaporative cooling pads, and presence of a canopy on the vertical air temperature variations were also investigated. The vertical air temperature variation increased approximately linearly with solar radiation. Use of an evaporative pad increased the temperature variation. Increasing ventilation rate resulted in reduced air temperature variation. The presence of a canopy modified the vertical temperature distribution and reduced temperature variations as well. DA - 2008/// PY - 2008/// DO - 10.13031/2013.25237 VL - 51 IS - 4 SP - 1443-1448 ER - TY - JOUR TI - Diagnostic accuracy of magnetic resonance imaging for meniscal tears in dogs affected with naturally occuring cranial cruciate ligament rupture AU - Blond, Laurent AU - Thrall, Donald E. AU - Roe, Simon C. AU - Chailleux, Nadege AU - Robertson, Ian D. T2 - VETERINARY RADIOLOGY & ULTRASOUND AB - A stifle magnetic resonance (MR) imaging protocol was developed based on the appearance of the cruciate ligaments and menisci in normal dogs. Proton density images were subjectively considered to have the highest likelihood of detecting a meniscal lesion. Following this initial evaluation, the accuracy of high‐field MR imaging to detect meniscal tears in dogs was evaluated in 11 dogs suffering from naturally occurring cranial cruciate ligament rupture. Dogs underwent MR imaging of the affected stifle before surgery. MR imaging and surgical findings were assessed independently, and then compared. Five tears of the medial meniscus were correctly diagnosed with MR imaging and 19 normal menisci were accurately characterized as such, based on MR images. In one medial meniscus, changes consistent with meniscal degeneration were seen on MR images but this was not seen at surgery. With regard to the lateral meniscus, one false positive diagnosis of a tear was made and this likely represented a normal variation. One other lateral meniscus had changes consistent with meniscal degeneration but, as with the similar lesion seen in the medial meniscus, this was not confirmed surgically. The global sensitivity of MR imaging for the diagnosis of a meniscal tear was 100% and the specificity was 94%. High‐field MR imaging is a reliable method to diagnose meniscal tears preoperatively and this may be useful in selecting the surgical approach to clinically abnormal joints and may decrease the need for arthrotomy. DA - 2008/// PY - 2008/// DO - 10.1111/j.1740-8261.2008.00401.x VL - 49 IS - 5 SP - 425-431 SN - 1058-8183 KW - magnetic resonance imaging KW - canine KW - stifle KW - meniscus ER - TY - JOUR TI - The impact of swine lagoon seepage on shallow groundwater quality: Groundwater remediation through lagoon closure and pumping AU - Cook, M. J. AU - Hathaway, J. M. AU - Evans, R. O. T2 - Transactions of the ASABE AB - Anaerobic lagoons have been used extensively since about 1960 to temporarily store and partially treat livestock waste from concentrated animal production facilities. An earlier study characterized an unlined swine lagoon located in the Middle Coastal Plain of North Carolina and detected elevated mineral nitrogen concentrations (nitrogen as both nitrate and total ammoniacal nitrogen) 38 m down gradient from the lagoon. As this site was shown to be a potential source of nonpoint-source pollution, further study was needed to characterize the aerial extent of the seepage plume and remediate the contaminated groundwater. Hydrologic and water quality monitoring of the site was conducted from March 1999 to September 2004, a period during which the lagoon went from being semiactive to completely closed out. Analysis of data collected prior to lagoon closure indicated that seepage from the lagoon traveled to a nearby channelized stream. Total ammoniacal nitrogen (TAN = NH3-N + NH4-N) concentrations from monitoring wells installed between the lagoon and the channelized stream averaged 121 mg L-1 of TAN, with the highest concentrations exceeding 170 mg L-1. TAN concentrations in the stream 150 m down gradient from the lagoon ranged from 10 to 25 mg L-1. Monitoring of groundwater levels and subsurface water quality continued following the closure of the lagoon in March 2001, as well as through the installation of a groundwater pumping system and construction of a wetland that received and treated the contaminated groundwater. The average hydraulic gradient decreased from 0.0033 m m-1, prior to the activation of a groundwater pumping system (Mar. 1999 to Jan. 2000) to 0.0010 m m-1 after pumping was initiated (Sept. 2000 to Sept. 2004). Although the direction of groundwater flow was unaffected by the addition of the pumping system and water control structure, the average hydraulic gradient was reduced by 70%. Since the installation of the pumping system, approximately 17,900 m3 of subsurface water has been pumped, removing 1200 kg of TN from the groundwater plume. TAN concentrations steadily declined from 120 mg L-1 at the onset of pumping in September 2000 to less than 6 mg L-1 by September 2004. DA - 2008/// PY - 2008/// DO - 10.13031/2013.24528 VL - 51 IS - 3 SP - 891-900 ER - TY - JOUR TI - Fuel prediction for specific tractor models AU - Grisso, R. D. AU - Vaughan, D. H. AU - Roberson, Gary T2 - Applied Engineering in Agriculture AB - Generalized models for fuel consumption are useful for budget and management scenarios, but may not have the ability to compare fuel consumption for several potential tractor configurations such as turbocharging and air densification models. The objective of this article is to develop a method that uses the Nebraska Tractor Test Lab (NTTL) data for a specific tractor model to predict fuel consumption for full and partial loads and for reduced throttle conditions. Using these equations, the fuel savings can be predicted for different operating and loading conditions. This method is compared with the generalized model and actual NTTL fuel consumption data. The results showed that 88% of tractors had an improved prediction with the new methodology. DA - 2008/// PY - 2008/// DO - 10.13031/2013.25139 VL - 24 IS - 4 SP - 423–428 ER - TY - JOUR TI - Isometry of potential suture attachment sites for the cranial cruciate ligament deficient canine stifle AU - Roe, Simon AU - Kue, J. AU - Gemma, J. T2 - Veterinary and Comparative Orthopaedics and Traumatology AB - For a suture that spans a joint to provide support without limiting range of motion, its attachment points on either side of the joint must remain the same distance from each other from full extension to full flexion. The effect of location of the tibial crest attachment for a fabello-tibial crest suture was studied in seven canine cadaveric stifles. The distance from a fabella marker to each of 11 tibial markers was determined from radiographs of each limb, as it progressed from 150 degrees to 130 degrees , 105 degrees , 90 degrees , 65 degrees and 45 degrees of flexion. The marker locations that were more proximal and cranial on the tibial crest had the least percent change in distance. The effect of anchoring the suture to the femur at a site other than the fabella was investigated using the same radiographs. Five marks were placed in a grid on the caudal portion of the femoral condyle and supracondylar region. The mean percent change in length from each femoral point to the five more proximal and cranial tibial markers was determined. The least change in length occurred for those femoral points located close to the origin of the cranial cruciate ligament. Locations more proximal or cranial resulted in large changes in length, particularly when matched with less ideal tibial locations. Although this study does not directly examine length changes in sutures, it demonstrates that there are some locations for the origin and insertion of an extracapsular suture that are associated with less length change than others, and also forms the basis for future investigations. DA - 2008/// PY - 2008/// DO - 10.1055/s-0037-1617364 VL - 21 IS - 3 SP - 215–220 ER - TY - JOUR TI - Workshop on Agricultural Air Quality: State of the science AU - Aneja, Viney P. AU - Blunden, Jessica AU - Roelle, Paul A. AU - Schlesinger, William H. AU - Knighton, Raymond AU - Niyogi, Dev AU - Gilliam, Wendell AU - Jennings, Greg AU - Duke, Clifford S. T2 - ATMOSPHERIC ENVIRONMENT AB - The first Workshop on Agricultural Air Quality: State of the Science was held at the Bolger Center in Potomac, Maryland from 4 to 8 June 2006. This international conference assembled approximately 350 people representing 25 nations from 5 continents, with disciplines ranging from atmospheric chemistry to soil science. The workshop was designed as an open forum in which participants could openly exchange the most current knowledge and learn about numerous international perspectives regarding agricultural air quality. Participants represented many stakeholder groups concerned with the growing need to assess agricultural impacts on the atmosphere and to develop beneficial policies to improve air quality. The workshop focused on identifying methods to improve emissions inventories and best management practices for agriculture. Workshop participants also made recommendations for technological and methodological improvements in current emissions measurement and modeling practices. The workshop commenced with a session on agricultural emissions and was followed by international perspectives from the United States, Europe, Australia, India, and South America. This paper summarizes the findings and issues of the workshop and articulates future research needs. These needs were identified in three general areas: (1) improvement of emissions measurement; (2) development of appropriate emission factors; and (3) implementation of best management practices (BMPs) to minimize negative environmental impacts. Improvements in the appropriate measurements will inform decisions regarding US farming practices. A need was demonstrated for a national/international network to monitor atmospheric emissions from agriculture and their subsequent depositions to surrounding areas. Information collected through such a program may be used to assess model performance and could be critical for evaluating any future regulatory policies or BMPs. The workshop concluded that efforts to maximize benefits and reduce detrimental effects of agricultural production need to transcend disciplinary, geographic, and political boundaries. Also, such efforts should involve natural and social scientists, economists, engineers, business leaders, and decision makers. The workshop came to the conclusion that through these collaborative efforts improvements in air quality from agricultural practices will begin to take effect. DA - 2008/4// PY - 2008/4// DO - 10.1016/j.atmosenv.2007.07.043 VL - 42 IS - 14 SP - 3195-3208 SN - 1873-2844 KW - nitrogen KW - ammonia KW - sulfur KW - hydrocarbons KW - biogenic VOCs KW - odor KW - emissions KW - emission factor KW - transport KW - transformation KW - crop and animal agriculture KW - measurements KW - modeling KW - best management practices KW - policy ER - TY - JOUR TI - Response of corn and cotton to starter phosphorus on soils testing very high in phosphorus AU - Cahill, Sheri AU - Johnson, Amy AU - Osmond, Deanna AU - Hardy, David T2 - AGRONOMY JOURNAL AB - Phosphorus from agricultural lands poses a problem in water resources. In 2003, more than 48% of soil samples submitted to the North Carolina Department of Agriculture and Consumer Services (NCDA&CS) soil testing laboratory tested very high in soil P (>120 mg dm −3 P). As soil test P increases, off‐site P loss increases, through erosion, soluble P runoff, or leaching. On soils testing above high soil test P (60–120 mg dm −3 P), studies from the northeast and midwest United States demonstrate that no corn ( Zea mays L.) or cotton ( Gossypium spp.) yield response from additional fertilizer is expected. However, there have been limited studies on the effects of starter‐P fertilizer on soils with very high P status in North Carolina and the southeast. Therefore, we undertook a study in the three physiographic regions (coastal plain, piedmont, and mountains) of North Carolina to determine if the use of starter‐P fertilizer would affect the growth of corn and cotton on soils having very high soil test P. Treatments were starter N and P, and starter N only. Treatment differences were not observed for corn, while the N‐only treatment had greater tissue N than the N‐ and P‐starter treatment in Piedmont cotton. Additionally, the use of only starter‐N is typically more cost effective than using both N and P starter fertilizer. For production, environmental, and economic reasons, starter‐P fertilizer is not warranted on North Carolina fields with very high soil test P values. DA - 2008/// PY - 2008/// DO - 10.2134/agronj2007.0202 VL - 100 IS - 3 SP - 537-542 SN - 0002-1962 ER - TY - JOUR TI - Quality assured measurements of animal building emissions: Odor concentrations AU - Jacobson, L. D. AU - Hetchler, B. P. AU - Schmidt, D. R. AU - Nicolai, R. E. AU - Heber, A. J. AU - Ni, J. Q. AU - Hoff, S. J. AU - Koziel, J. A. AU - Zhang, Y. H. AU - Beasley, D. B. AU - Parker, D. B. T2 - Journal of the Air & Waste Management Association DA - 2008/// PY - 2008/// DO - 10.3155/1047-3289.S8.6.806 VL - 58 IS - 6 SP - 806-811 ER - TY - JOUR TI - Measurement and analysis of ammonia and hydrogen sulfide emissions from a mechanically ventilated swine confinement building in North Carolina AU - Blunden, Jessica AU - Aneja, Viney P. AU - Westerman, Phillip W. T2 - ATMOSPHERIC ENVIRONMENT AB - Emissions of atmospheric ammonia–nitrogen (NH3–N, where NH3–N=(1417)NH3) and hydrogen sulfide (H2S) were measured from a finishing swine confinement house at a commercial pig farm in eastern North Carolina. Continuous simultaneous NH3–N and H2S emissions were made for ∼1-week period during four different seasons. The number of pigs contained in the house varied from ∼850 to 900 with average weights ranging from ∼38 to 88 kg. Average NH3–N concentrations were highest during the winter and spring sampling periods, 8.91±4.61 and 8.44±2.40 ppm, respectively, and lower during the summer and fall, 2.45±1.14 and 4.27±0.71 ppm, respectively. Measured average H2S concentrations were 673±282, 429±223, 47±18, and 304±88 ppb during winter, spring, summer, and fall, respectively. Generally, the H2S concentrations were approximately an order of magnitude less than NH3–N during winter, spring, and fall, and two orders of magnitude smaller during the summer season. The average ambient temperature ranged from 5.5 to 22.3 °C while the average barn temperature measured at the outlet fans ranged from 19.0 to 26.0 °C in the winter and summer, respectively. The average fan ventilation rates varied from 253 m3 min−1 during the fall sampling period to 1024 m3 min−1 during summer. Calculated total emission rates for both NH3–N and H2S were highest during the spring, 4519±1639 g N day−1 and 481±142 g day−1, respectively. Emissions were lowest during the fall season for NH3–N (904±568 g N day−1) and the summer season for H2S (82±49 g day−1). Normalized NH3–N emission rates were highest in winter and spring (33.6±21.9 and 30.6±11.1 g N day−1 AU−1, where 1 AU (animal unit)=500 kg) and lowest during summer and fall (24.3±12.4 and 11.8±7.4 g N day−1 AU−1). Normalized H2S emissions were highest during the winter and spring seasons (4.2±2.1 and 3.3±1.0 g day−1 AU−1) and were lowest in summer and fall (1.2±0.7 and 1.7±0.5 g day−1 AU−1). DA - 2008/4// PY - 2008/4// DO - 10.1016/j.atmosenv.2007.06.040 VL - 42 IS - 14 SP - 3315-3331 SN - 1352-2310 KW - ammonia KW - hydrogen sulfide KW - swine barns KW - CAFOs ER - TY - JOUR TI - Field evaluation of level spreaders in the Piedmont of North Carolina AU - Hathaway, J. M. AU - Hunt, W. F. T2 - Journal of Irrigation and Drainage Engineering AB - Level spreaders are commonly used in combination with riparian buffers as a stormwater best management practice in many parts of the United States. These systems have not been extensively studied in urbanized environments to determine if they can provide a long-term water quality benefit. In winter 2005, 24 level spreaders were evaluated in the Piedmont of North Carolina. Detailed observations were made at 20 of these locations. The results of the study indicate that level spreaders may not be the versatile structure they are perceived to be. No level spreader-riparian buffer system was able to provide diffuse flow through the riparian buffer from the level spreader to the stream. Common causes for failure to maintain diffuse flow included: lack of maintenance (12 cases), poor design (11), riparian topography/content (11), level spreader lip not level (seven), built with easily eroded materials (six), poor construction methods (three), and human interference (two). This field evaluation indicates that level spreader systems may need design revisions, construction guidance, and maintenance requirements before they continue to be used en masse. DA - 2008/// PY - 2008/// DO - 10.1061/(ASCE)0733-9437(2008)134:4(538) VL - 134 IS - 4 SP - 538-542 ER - TY - JOUR TI - Fecal coliform export from four coastal North Carolina areas AU - Line, D. E. AU - White, N. M. AU - Kirby-Smith, W. W. AU - Potts, J. D. T2 - JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION AB - Abstract: Fecal coliform (FC) bacteria in coastal waters impair the use of these waters for shellfish harvesting and recreation. This study was designed to quantify and compare FC levels and export in two coastal watersheds with different land uses. Continuous monitoring of rainfall and discharge at three sites in the Jumping Run Creek watershed and one site in the Pettiford Creek watershed were conducted during a 4.5‐year period. Primary land use in the drainage area of one of the three Jumping Run Creek sites is low density industrial, while the other two are residential. Land use in the Pettiford Creek watershed is managed national forest. Nonstorm or base‐flow grab and flow‐proportional storm‐event samples were collected and analyzed for turbidity, conductivity, suspended sediment, nitrogen, phosphorus, and FC. Geometric mean FC levels for the Jumping Run Creek monitoring sites ranged from 593 to 2,096 mpn/100 ml, while the mean level at the Pettiford Creek site was 191 mpn/100 ml. Levels of most other parameters were greater in storm discharge from the Jumping Run Creek sites as compared to Pettiford Creek indicating that pollutant export from a watershed increases with development. Statistical analysis of the monitoring data suggested that FC levels in stormwater samples consistently increased with storm rainfall, but were not consistently correlated with any other parameter, including total suspended solids. Multivariate analysis indicated that the weekly FC export for each of the four sites was lowest during the December‐February quarter. Export was highest during the spring and summer at the Jumping Run Creek sites, while for the Pettiford Creek site, FC export was highest during September‐November. The cause of the seasonal variability was unknown but was thought to be associated with human activity in the watersheds. DA - 2008/6// PY - 2008/6// DO - 10.1111/j.1752-1688.2008.00185.x VL - 44 IS - 3 SP - 606-617 SN - 1752-1688 KW - stormwater KW - fecal coliform KW - development KW - monitoring ER - TY - JOUR TI - Evaluating the effectiveness of two stormwater wetlands in North Carolina AU - Line, D. E. AU - Jennings, G. D. AU - Shaffer, M. B. AU - Calabria, J. AU - Hunt, W. F. T2 - Transactions of the ASABE DA - 2008/// PY - 2008/// VL - 51 IS - 2 SP - 521-528 ER - TY - JOUR TI - Microbial pretreatment of cotton stalks by solid state cultivation of Phanerochaete chrysosporium AU - Shi, Jian AU - Chinn, Mari S. AU - Sharma-Shivappa, Ratna R. T2 - BIORESOURCE TECHNOLOGY AB - White rot fungi degrade lignin and have biotechnological applications in conversion of lignocellulose to valuable products. Pretreatment is an important processing step to increase the accessibility of cellulosic material in plant biomass, impacting efficiency of subsequent hydrolysis and fermentation. This study investigated microbial pretreatment of cotton stalks by solid state cultivation (SSC) using Phanerochaete chrysosporium to facilitate the conversion into ethanol. The effects of substrate moisture content (M.C.; 65%, 75% and 80% wet-basis), inorganic salt concentration (no salts, modified salts without Mn(2+), modified salts with Mn(2+)) and culture time (0-14 days) on lignin degradation (LD), solids recovery (SR) and availability of carbohydrates (AOC) were examined. Moisture content significantly affected lignin degradation, with 75% and 80% M.C. degrading approximately 6% more lignin than 65% M.C. after 14 days. Within the same moisture content, treatments supplemented with salts were not statistically different than those without salts for LD and AOC. Within the 14day pretreatment, additional time resulted in greater lignin degradation, but indicated a decrease in SR and AOC. Considering cost, solid state cultivation at 75% M.C. without salts was the most preferable pretreatment resulting in 27.6% lignin degradation, 71.1% solids recovery and 41.6% availability of carbohydrates over a period of 14 days. Microbial pretreatment by solid state cultivation has the potential to be a low cost, environmentally friendly alternative to chemical approaches. Moisture relationships will be significant to the design of an effective microbial pretreatment process using SSC technology. DA - 2008/9// PY - 2008/9// DO - 10.1016/j.biortech.2007.11.069 VL - 99 IS - 14 SP - 6556-6564 SN - 1873-2976 KW - cotton stalk KW - pretreatment KW - phanerochaete chrysosporium KW - bioethanol KW - lignin ER - TY - JOUR TI - Evaluation of wraps covering the distal aspect of pelvic limbs for prevention of bacterial strike-through in an ex vivo canine model AU - Vince, Kent J. AU - Lascelles, B. Duncan X. AU - Mathews, Kyle G. AU - Altier, Craig AU - Roe, Simon C. T2 - VETERINARY SURGERY AB - To determine differences in bacterial strike-through for materials commonly used to cover the distal aspect of the pelvic limb during operative site preparation.Randomized block design; ex vivo model.Canine cadaveric pelvic limbs (n=40).Pelvic limbs (n=40) were randomly assigned to 4 treatment groups: Group 1=Vetrap+sterile Coban; Group 2=latex glove+Vetrap+sterile Coban; Group 3=latex glove+Vetrap+sterile Coban+sterile latex glove+sterile Coban; and Group 4=latex glove+Vetrap+sterile disposable drape+sterile Coban. Limbs were contaminated with a standardized bacterial solution and routinely prepared using the assigned distal leg wrap. Bandages were fluid challenged with a saline (0.9% NaCl) solution-soaked laparotomy sponge for 30 seconds. The wrap surface was sampled for microbial culture before surgical preparation, immediately after, and 60 minutes after applying a sterile leg wrap.Bacterial growth occurred in all Group 1 cultures, 90% of Group 2 cultures, and none of the Group 3 and 4 cultures, 60 minutes after applying the sterile wrap.A distal leg wrap of Vetrap+sterile Coban is not effective in preventing bacterial strike-through.If similar results occur in the live animal, then a sterile impermeable barrier must be incorporated into the distal leg wrap to prevent bacterial strike-through. DA - 2008/6// PY - 2008/6// DO - 10.1111/j.1532-950X.2008.00395.x VL - 37 IS - 4 SP - 406-411 SN - 0161-3499 ER - TY - JOUR TI - Sensor-based automation of irrigation on bermudagrass, during wet weather conditions AU - Cardenas-Lailhacar, B. AU - Dukes, M. D. AU - Miller, G. L. T2 - Journal of Irrigation and Drainage Engineering AB - New technologies could improve irrigation efficiency of turfgrass, promoting water conservation and reducing environmental impacts. The objectives of this research were to quantify irrigation water use and to evaluate turf quality differences between (1) time-based scheduling with and without a rain sensor (RS); (2) a time-based schedule compared to a soil moisture sensor (SMS)-based irrigation system; and (3) different commercially available SMS systems. The experimental area consisted of common bermudagrass [Cynodon dactylon (L.) Pers.] plots (3.7m×3.7m), located in Gainesville, Fla. The monitoring period took place from July 20 to December 14, 2004, and from March 25 to August 31, 2005. SMS-based treatments consisted of irrigating one, two, or seven days a week, each with four different commercial SMS brands. Time-based treatments with or without RS and a nonirrigated treatment were also implemented. Significant differences in turfgrass quality among treatments were not detected due to the sustained wet weather conditions during the testing periods. The treatment with the rain sensor resulted in 34% less water applied than that without the rain sensor (2-WORS) treatment. Most SMS brands recorded irrigation water savings compared to 2-WORS, ranging from 69 to 92% for three of four SMSs tested, depending on the irrigation frequency. Therefore, SMS systems represent a promising technology because of the water savings that they can achieve during wet weather conditions while maintaining acceptable turfgrass quality. DA - 2008/// PY - 2008/// DO - 10.1061/(ASCE)0733-9437(2008)134:2(120) VL - 134 IS - 2 SP - 120-128 ER - TY - JOUR TI - Influence of moisture content and cultivation duration on Clostridium thermocellum 27405 end-product formation in solid substrate cultivation on Avicel AU - Chinn, Mari S. AU - Nokes, Sue E. AU - Strobel, Herbert J. T2 - BIORESOURCE TECHNOLOGY AB - Avicel serves as a model microcrystalline cellulose substrate for investigations of cellulolytic microbial performance and cellulase enzyme systems in submerged liquid cultures. Clostridium thermocellum is a thermophilic, anaerobic bacterium capable of degrading lignocellulose and fermenting it to ethanol and other products, suggesting the native growth environment is similar to that supported by solid substrate cultivation. Few studies have examined the effects of process parameters on the metabolism of thermophilic anaerobes in solid substrate cultivation, however. The effects of solid substrate cultivation (SSC) substrate moisture content (30%, 50% and 70% wet-basis) and cultivation duration (2, 4 and 8 days) on the metabolic activity of C. thermocellum 27405 on Avicel was studied. The 70% substrate moisture content SSC culture yielded total end-product concentrations that were comparable to submerged liquid cultures. The SSC cultivation conditions with the highest end-product formation on Avicel were the combination of 70% substrate moisture content and cultivation duration period of 4 days, producing approximately 100 mM of total end-products. The ethanol and lactate concentrations were fairly constant and did not change significantly over time in SSC. Acetate production was more dependent on the cultivation conditions in SSC and was significant for both the 70% substrate moisture content SSC and liquid cultivation experiments, making up on average 56% and 86% of total end-products, respectively. Performance of C. thermocellum 27405 in SSC was more dependent on the kinetic properties rather than the thermodynamic properties of substrate moisture content. High substrate loadings in C. thermocellum cultivation affected product ratios, resulting in the higher observed acetate production. In addition, cessation of metabolism was observed prior to complete Avicel conversion; the mechanisms involved need further investigation. DA - 2008/5// PY - 2008/5// DO - 10.1016/j.biortech.2007.04.052 VL - 99 IS - 7 SP - 2664-2671 SN - 0960-8524 KW - C. thermocellum KW - Avicel KW - solid substrate cultivation (SSC) KW - moisture content KW - thermophilic ER - TY - JOUR TI - Inhibition of anaerobic digestion process: A review AU - Chen, Ye AU - Cheng, Jay J. AU - Creamer, Kurt S. T2 - BIORESOURCE TECHNOLOGY AB - Anaerobic digestion is an attractive waste treatment practice in which both pollution control and energy recovery can be achieved. Many agricultural and industrial wastes are ideal candidates for anaerobic digestion because they contain high levels of easily biodegradable materials. Problems such as low methane yield and process instability are often encountered in anaerobic digestion, preventing this technique from being widely applied. A wide variety of inhibitory substances are the primary cause of anaerobic digester upset or failure since they are present in substantial concentrations in wastes. Considerable research efforts have been made to identify the mechanism and the controlling factors of inhibition. This review provides a detailed summary of the research conducted on the inhibition of anaerobic processes. The inhibitors commonly present in anaerobic digesters include ammonia, sulfide, light metal ions, heavy metals, and organics. Due to the difference in anaerobic inocula, waste composition, and experimental methods and conditions, literature results on inhibition caused by specific toxicants vary widely. Co-digestion with other waste, adaptation of microorganisms to inhibitory substances, and incorporation of methods to remove or counteract toxicants before anaerobic digestion can significantly improve the waste treatment efficiency. DA - 2008/7// PY - 2008/7// DO - 10.1016/j.biortech.2007.01.057 VL - 99 IS - 10 SP - 4044-4064 SN - 1873-2976 KW - anaerobic digestion KW - agricultural wastes KW - industrial wastes KW - inhibition KW - municipal wastes ER - TY - JOUR TI - Implications of urine-to-feces ratio in the thermophilic anaerobic digestion of swine waste AU - Creamer, K. S. AU - Williams, C. M. AU - Chen, Y. AU - Cheng, J. J. T2 - WATER ENVIRONMENT RESEARCH AB - Thermophilic anaerobic digestion of swine manure represents a potential waste treatment technology to address environmental concerns, such as odor emissions and removal of pathogenic microorganisms. However, there are concerns relative to the stability of this process when swine manure is the sole substrate. In this study, the potential of biogas production from swine manure as the sole substrate under thermophilic (50°C) conditions was investigated in the laboratory, to determine whether separation of urine and feces as part of the waste collection process would benefit anaerobic digestion. Effluent from a continuously stirred tank reactor was used as the inoculum for batch tests, in which the substrate contained three different concentrations of urine (urine‐free, as‐excreted urine‐to‐feces ratio and double the as‐excreted urine‐to‐feces ratio). Inocula were acclimated to these same urine‐to‐feces ratios to determine methane production. Results show that both urine‐free and as‐excreted substrates were not inhibitory to anaerobic inocula. Anaerobic microorganisms can be readily acclimated to substrate with double the as‐excreted urine concentration, which contained nitrogen concentrations up to 7.20 g/L. Cumulative methane production reached similar levels in the batch tests, regardless of the substrate urine concentration. DA - 2008/3// PY - 2008/3// DO - 10.2175/106143007X184717 VL - 80 IS - 3 SP - 267-275 SN - 1554-7531 KW - anaerobic digestion KW - inhibition KW - feces KW - swine waste KW - thermophilic KW - urine ER - TY - JOUR TI - Design and evaluation of a regenerating scrubber for reducing animal house emissions AU - Shah, Sanjay AU - Westerman, P. W. AU - Munilla, R. D. AU - Adcock, M. E. AU - Baughman, G. R. T2 - Transactions of the ASABE AB - Animal houses can emit substantial quantities of air pollutants. Compared with other pollutants, ammonia is emitted from animal houses in relatively large quantities and can have adverse public health and environmental impacts. This article describes the development and evaluation of a novel scrubber prototype, consisting of an endless polypropylene screen running in a trough of alum solution, that could be used to reduce ammonia emissions from animal houses. When building exhaust ventilation air contacts the screen, ammonia is dissolved in the aqueous solution on the screen and transported into the trough. Low ammonia concentration (<5 mg m-3) evaluations were conducted by connecting the scrubber to a pit ventilation fan in a hog finishing house. Higher ammonia concentration (7.6 to 26.6 mg m-3) evaluations were conducted by placing the scrubber inlet adjacent to a composting bin spiked with urea. Over >66 h of evaluation under low and high concentration conditions, with a weighted average airflow rate of 0.93 m3 s-1 and velocity of 0.52 m s-1, the scrubber reduced ammonia emissions by 58.3%. Compared with commercial spray and packed column scrubbers used in industry, it had a lower pressure drop (~110 Pa). It also had a low water consumption of ~1 mL m-3 treated air. Further evaluation of the scrubber in different types of animal houses and for different pollutants is required. Its design should be improved to increase ammonia removal efficiency and reduce pressure drop, footprint size, and cost. There is also need to model gas transfer in this type of scrubber. DA - 2008/// PY - 2008/// DO - 10.13031/2013.24217 VL - 51 IS - 1 SP - 243–250 ER - TY - JOUR TI - Ammonia assessment from agriculture: US status and needs AU - Aneja, Viney P. AU - Blunden, Jessica AU - James, Kristen AU - Schlesinger, William H. AU - Knighton, Raymond AU - Gilliam, Wendell AU - Jennings, Greg AU - Niyogi, Dev AU - Cole, Shawn T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - Recent studies suggest that human activities accelerate the production of reactive nitrogen on a global scale. Increased nitrogen emissions may lead to environmental impacts including photochemical air pollution, reduced visibility, changes in biodiversity, and stratospheric ozone depletion. In the last 50 yr, emissions of ammonia (NH3), which is the most abundant form of reduced reactive nitrogen in the atmosphere, have significantly increased as a result of intensive agricultural management and greater livestock production in many developed countries. These agricultural production practices are increasingly subject to governmental regulations intended to protect air resources. It is therefore important that an accurate and robust agricultural emission factors database exist to provide valid scientific support of these regulations. This paper highlights some of the recent work that was presented at the 2006 Workshop on Agricultural Air Quality in Washington, D.C. regarding NH3 emissions estimates and emission factors from agricultural sources in the U.S. and Europe. In addition, several best management practices are explored as the scientific community attempts to maximize the beneficial use of reactive nitrogen while simultaneously minimizing negative environmental impacts. DA - 2008/// PY - 2008/// DO - 10.2134/jeq2007.0002in VL - 37 IS - 2 SP - 515-520 SN - 1537-2537 ER - TY - JOUR TI - Afield study of green roof hydrologic and water quality performance AU - Hathaway, A. M. AU - Hunt, W. F. AU - Jennings, G. D. T2 - Transactions of the ASABE DA - 2008/// PY - 2008/// VL - 51 IS - 1 SP - 37-44 ER - TY - JOUR TI - A technique to monitor insect behavior utilizing infrared emitters and detectors AU - Thompson, Sarah R. AU - Brandenburg, Rick L. AU - Roberson, Gary T. AU - Lineberger, Barry T2 - JOURNAL OF ENTOMOLOGICAL SCIENCE DA - 2008/1// PY - 2008/1// DO - 10.18474/0749-8004-43.1.143 VL - 43 IS - 1 SP - 143-152 SN - 0749-8004 KW - behavior KW - detector KW - emitter KW - infrared KW - LabVIEW (TM) software KW - mole cricket KW - photosensor ER - TY - JOUR TI - Pollutant removal and peak flow mitigation by a bioretention cell in urban Charlotte, NC AU - Hunt, W. F. AU - Smith, J. T. AU - Jadlocki, S. J. AU - Hathaway, J. M. AU - Eubanks, P. R. T2 - Journal of Environmental Engineering (New York, N.Y.) AB - Bioretention is a stormwater treatment practice that has gained popularity due to its aesthetics, potential to reduce flooding, and early documented improvements to stormwater quality. A bioretention cell in an urban setting was examined in Charlotte, N.C. from 2004 to 2006. Flow-weighted, composite water quality samples were collected for 23 events and analyzed for TKN, NH4-N, NO2-3-N, TP, TSS, BOD-5, Cu, Zn, Fe, and Pb. Grab samples were collected from 19 storms for fecal coliform and 14 events for Escherichia coli (E. coli). There were significant reductions (p<0.05) in the concentrations of TN, TKN, NH4-N, BOD-5, fecal coliform, E. Coli, TSS, Cu, Zn, and Pb. Iron concentrations significantly increased (p<0.05). NO2-3-N concentrations were essentially unchanged. Efficiency ratios for TN, TKN, NH4-N, TP, and TSS were 0.32, 0.44, 0.73, 0.31, and 0.60, respectively. Fecal coliform and E. coli efficiency ratios were 0.69 and 0.71, respectively. Efficiency ratios for Zn, Cu, and Pb were 0.77, 0.54, and 0.31, respectively. Concentrations of Fe increased by 330%. The peak outflow of the bioretention cell for 16 storms with less than 42mm of rainfall was at least 96.5% less than the peak inflow, with a mean peak flow reduction being 99%. These results indicated that in an urban environment, bioretention systems can reduce concentrations of most target pollutants, including pathogenic bacteria indicator species. Additionally, bioretention can effectively reduce peak runoff from small to midsize storm events. DA - 2008/// PY - 2008/// DO - 10.1061/(asce)0733-9372(2008)134:5(403) VL - 134 IS - 5 SP - 403-408 ER - TY - JOUR TI - Integrated practices for reducing sediment loss from Piedmont tobacco fields AU - Hazel, D. W. AU - Franklin, E. C. AU - Thomas, K. T. AU - Jennings, G. D. T2 - JOURNAL OF SOIL AND WATER CONSERVATION AB - We evaluated the effectiveness of three best management practices for flue-cured tobacco production—reduced tillage, grassed field-side filter zones, and forested filter zones—to determine the total reduction in suspended solids from storm water runoff. Use of reduced tillage in comparison with conventional tillage decreased total suspended solids leaving tobacco fields by 82%. Grassed field-side filter zones functioned very well in retaining solids in early summer but were overloaded by late summer. Forested filter zones were able to back up the grassed filter zones when they overloaded and exported total suspended solids to the forested filter zones. In combination, grassed filter zones and forested filter zones retained 68% to 69% of total suspended solids, respectively. Dense vegetation in the cutover forested filter zone more than doubled its capacity to detain solids, compared to the same forested filter zone when it was covered by mature mixed pine-hardwood. Use of these best management practices in series can significantly reduce sediment loss from tobacco; however, use of reduced-till may reduce tobacco yield and quality. DA - 2008/// PY - 2008/// DO - 10.2489/jswc.63.3.143 VL - 63 IS - 3 SP - 143-152 SN - 0022-4561 KW - best management practices KW - filter zones KW - nonpoint source pollution KW - runoff KW - sediments KW - tillage ER - TY - JOUR TI - Comparing denitrification rates and carbon sources in commercial scale upflow denitrification biological filters in aquaculture AU - Hamlin, H. J. AU - MichaelS, J. T. AU - Beaulaton, C. M. AU - Graham, W. F. AU - Dutt, W. AU - Steinbach, P. AU - Losordo, T. M. AU - Schrader, K. K. AU - Main, K. L. T2 - Aquacultural Engineering AB - Aerobic biological filtration systems employing nitrifying bacteria to remediate excess ammonia and nitrite concentrations are common components of recirculating aquaculture systems (RAS). However, significant water exchange may still be necessary to reduce nitrate concentrations to acceptable levels unless denitrification systems are included in the RAS design. This study evaluated the design of a full scale denitrification reactor in a commercial culture RAS application. Four carbon sources were evaluated including methanol, acetic acid, molasses and Cerelose™, a hydrolyzed starch, to determine their applicability under commercial culture conditions and to determine if any of these carbon sources encouraged the production of two common “off-flavor” compounds, 2-methyisoborneol (MIB) or geosmin. The denitrification design consisted of a 1.89 m3 covered conical bottom polyethylene tank containing 1.0 m3 media through which water up-flowed at a rate of 10 lpm. A commercial aquaculture system housing 6 metric tonnes of Siberian sturgeon was used to generate nitrate through nitrification in a moving bed biological filter. All four carbon sources were able to effectively reduce nitrate to near zero concentrations from influent concentrations ranging from 11 to 57 mg/l NO3–N, and the maximum daily denitrification rate was 670–680 g nitrogen removed/m3 media/day, regardless of the carbon source. Although nitrite production was not a problem once the reactors achieved a constant effluent nitrate, ammonia production was a significant problem for units fed molasses and to a less extent Cerelose™. Maximum measured ammonia concentrations in the reactor effluents for methanol, vinegar, Cerelose™ and molasses were 1.62 ± 0.10, 2.83 ± 0.17, 4.55 ± 0.45 and 5.25 ± 1.26 mg/l NH3–N, respectively. Turbidity production was significantly increased in reactors fed molasses and to a less extent Cerelose™. Concentrations of geosmin and MIB were not significantly increased in any of the denitrification reactors, regardless of carbon source. Because of its very low cost compared to the other sources tested, molasses may be an attractive carbon source for denitrification if issues of ammonia production, turbidity and foaming can be resolved. DA - 2008/// PY - 2008/// DO - 10.1016/j.aquaeng.2007.11.003 VL - 38 IS - 2 SP - 79-92 ER - TY - JOUR TI - Rule-based Mamdani-type fuzzy modeling of skin permeability AU - Keshwani, Deepak R. AU - Jones, David D. AU - Meyer, George E. AU - Brand, Rhonda M. T2 - APPLIED SOFT COMPUTING AB - Two Mamdani type fuzzy models (three inputs–one output and two inputs–one output) were developed to predict the permeability of compounds through human skin. The models were derived from multiple data sources including laboratory data, published data bases, published statistical models, and expert opinion. The inputs to the model include information about the compound (molecular weight and octonal–H2O partition coefficient) and the application temperature. One model included all three parameters as inputs and the other model only included information about the compound. The values for mole molecular weight ranged from 30 to 600 Da. The values for the log of the octonal–H2O partition coefficient ranged from −3.1 to 4.34. The values for the application temperature ranged from 22 to 39 °C. The predicted values of the log of permeability coefficient ranged from −5.5 to −0.08. Each model was a collection of rules that express the relationship of each input to the permeability of the compound through human skin. The quality of the model was determined by comparing predicted and actual fuzzy classification and defuzzification of the predicted outputs to get crisp values for correlating estimates with published values. A modified form of the Hamming distance measure is proposed to compare predicted and actual fuzzy classification. An entropy measure is used to describe the ambiguity associated with the predicted fuzzy outputs. The three input model predicted over 70% of the test data within one-half of a fuzzy class of the published data. The two input model predicted over 40% of the test data within one-half of a fuzzy class of the published data. Comparison of the models show that the three input model exhibited less entropy than the two input model. DA - 2008/1// PY - 2008/1// DO - 10.1016/j.asoc.2007.01.007 VL - 8 IS - 1 SP - 285-294 SN - 1568-4946 KW - Mamdani fuzzy modeling KW - Hamming distance KW - skin permeability ER - TY - JOUR TI - Influence of Mehlich-3 extractable aluminum on phosphorus retention in organic soils AU - Dell'Olio, Laura A. AU - Maguire, Rory O. AU - Osmond, Deanna L. T2 - SOIL SCIENCE AB - Phosphorus (P) regulations in North Carolina (NC) assume that organic soils have little ability to retain P, and losses of P from these soils are of concern for the health of aquatic ecosystems. However, recent research has indicated decreased water-soluble P (WSP) in organic soils in the presence of high Al concentrations. Our objectives were to determine (i) the concentrations of organic matter (OM), and Mehlich-3 Al and Fe in deep and shallow organic soils in NC, and (ii) how these factors affect P retention. We sampled four organic soil series and determined Mehlich-3 P, Al, and Fe (M3P, M3Al, M3Fe), WSP, total P, pH, particle size distribution, and OM. Water-soluble P and M3P were also measured in a 21-day incubation study, in which P was added at a rate equivalent to 150 kg P ha−1. The main cation responsible for P retention was Al, and the mean topsoil M3Al concentrations (1926 mg kg−1) in these organic soils were close to three times higher than those observed in another study of mostly mineral NC soils. Mehlich-3 Fe was not significantly related to WSP. Retention of added P was negatively related to OM and positively related to M3Al. The ratio of OM and M3Al was the best predictor of WSP and retention of added P. The results from this study indicate that organic soils can retain P more strongly than previously thought, and their ability to retain P is best described by the ratio of OM and M3Al. DA - 2008/2// PY - 2008/2// DO - 10.1097/ss.0b013e31815d8eb7 VL - 173 IS - 2 SP - 119-129 SN - 1538-9243 KW - aluminum KW - organic matter KW - phosphorus ER - TY - JOUR TI - Inactivation of bacterial pathogens in human milk by high-pressure processing AU - Viazis, S. AU - Farkas, B. E. AU - Jaykus, L. A. T2 - JOURNAL OF FOOD PROTECTION AB - Low-temperature, long-time (LTLT) pasteurization assures the safety of banked human milk; however, heat can destroy important nutritional biomolecules. High-pressure processing (HPP) shows promise as an alternative for pasteurization of breast milk. The purpose of this study was to investigate the efficacy of HPP for inactivation of selected bacterial pathogens in human milk. Human milk was inoculated with one of five pathogens (10(8) to 10(9) CFU/ml), while 0.1% peptone solution solutions with the same levels of each organism were used as controls. The samples were subjected to 400 MPa at 21 to 31 degrees C for 0 to 50 min or to 62.5 degrees C for 0 to 30 min (capillary tube method) to simulate LTLT pasteurization. Tryptic soy agar and selective media were used for enumeration. Traditional thermal pasteurization resulted in inactivation (> 7 log) of all pathogens within 10 min. In human milk and in peptone solution, a 6-log reduction was achieved after 30 min of HPP for Staphylococcus aureus ATCC 6538. After 30 min, S. aureus ATCC 25923 was reduced by 8 log and 6 log in human milk and peptone solution, respectively. Treatments of 4 and 7 min resulted in an 8-log inactivation of Streptococcus agalactiae ATCC 12927 in human milk and peptone solution, respectively, while Listeria monocytogenes ATCC 19115 required 2 min for an 8-log inactivation in human milk. Escherichia coli ATCC 25922 was inactivated by 8 log after 10 min in peptone solution and by 6 log after 30 min in human milk. These data suggest that HPP may be a promising alternative for pasteurization of human milk. Further research should evaluate the efficacy of HPP in the inactivation of relevant viral pathogens. DA - 2008/1// PY - 2008/1// DO - 10.4315/0362-028X-71.1.109 VL - 71 IS - 1 SP - 109-118 SN - 1944-9097 ER - TY - JOUR TI - Amantadine in a multimodal analgesic regimen for alleviation of refractory osteoarthritis pain in dogs AU - Lascelles, B. D. X. AU - Gaynor, J. S. AU - Smith, E. S. AU - Roe, S. C. AU - Marcellin-Little, D. J. AU - Davidson, G. AU - Boland, E. AU - Carr, J. T2 - JOURNAL OF VETERINARY INTERNAL MEDICINE AB - Background: Nonsteroidal anti‐inflammatory drugs (NSAIDs) do not always provide sufficient pain relief in dogs with osteoarthritis (OA). Hypothesis: The use of amantadine in addition to NSAID therapy will provide improved pain relief when compared with the use of nonsteroidal analgesics alone in naturally occurring OA in dogs. Animals: Thirty‐one client‐owned dogs with pelvic limb lameness despite the administration of an NSAID. Methods: The study was randomized, blinded, and placebo controlled with parallel groups (days 21–42). On day 0, analgesic medications were discontinued. On day 7, all dogs received meloxicam for 5 weeks. On day 21, all dogs received amantadine (3–5 mg/kg once daily per os) or placebo for 21 days, in addition to receiving meloxicam. Assessments were performed before the study and on days 7, 21, and 42. Primary outcome measures were blinded owner assessments of activity using client‐specific outcome measures (CSOM) on days 0, 7, 21, and 42. Data were analyzed by a mixed model approach. Results: For CSOM activity, there was a significant time by treatment effect ( P =.009). On the basis of the planned post hoc t ‐tests of postrandomization means, there was a significant difference between treatment groups on day 42 ( P =.030), with the amantadine group being more active. Conclusions and Clinical Importance: In dogs with osteoarthritic pain refractory to an NSAID, physical activity is improved by the addition of amantadine. Amantadine might be a useful adjunct therapy for the clinical management of canine osteoarthritic pain. DA - 2008/// PY - 2008/// DO - 10.1111/j.1939-1676.2007.0014.x VL - 22 IS - 1 SP - 53-59 SN - 1939-1676 KW - dog KW - nonsteroidal anti-inflammatory KW - owner KW - pain KW - subjective assessment ER - TY - CONF TI - Microwave-based alkali pretreatment of lignocelluloses AU - Keshwani, D. R. AU - Cheng, J. J. C2 - 2008/// C3 - IBE Annual Meeting (Chapel Hill, North Carolina) DA - 2008/// ER -