TY - CONF TI - The influence of organic matter on E. coli soil sorption AU - Guzman, J. AU - Fox, G.A. AU - Penn, C.J. T2 - ASABE Annual International Conference C2 - 2009/// C3 - Proceedings of the ASABE Annual International Conference: 2009 Reno, Nevada, June 21 - June 24, 2009. CY - Reno, NV DA - 2009/// PY - 2009/6/21/ PB - American Society of Agricultural and Biological Engineers ER - TY - JOUR TI - Une approche quantitative du rôle de la fréquence d’échantillonnage sur les incertitudes associées aux calculs des flux et des concentrations moyennes en nitrate en Bretagne AU - Birgand, F. AU - Faucheux, C. AU - Gruau, G. AU - Augeard, B. AU - Moatar, F. AU - Meybeck, M. AU - Bouédo, A. AU - Bordenave, P. T2 - Ingénieries : eau agriculture territoires DA - 2009/// PY - 2009/// VL - 59-60 SP - 23–37 ER - TY - RPRT TI - North River Wetlands Restoration Research AU - Evans, R.O. AU - Burchell, M.R. AU - Vepraskas, M. AU - Broome, S.W. AU - Shear, T. AU - Bass, K.L. AU - Grabow, G. A3 - North Carolina Ecosystem Enhancement Program DA - 2009/8// PY - 2009/8// M1 - Contract AW03007 M3 - Final Report PB - North Carolina Ecosystem Enhancement Program SN - Contract AW03007 ER - TY - CONF TI - Biological Characteristics of Aerosols Emitted From A Layer Operation In Southeastern U.S. AU - Wang, Lingjuan AU - Li, Qianfeng AU - Esch, Keith AU - Simmons, Otto D, III AU - Classen, John AU - Beasley, David B T2 - American Society of Agricultural and Biological Engineers Annual International Meeting AB - This preliminary study was to investigate biological characteristics of aerosols emitted from a commercial layer farm (egg production farm). Bioaerosol samples were taken on this farm at five sampling locations covering emission source (inside a layer barn) and four ambient stations at four wind directions. All glass impingers (AGI) were used for the field sampling. The AGI fluid samples were plated in duplicate on Trypticase Soy Agar (TSA) for growth of bacteria and Sabouraud Dextrose Agar (SDA) for growth of fungi. The most prominent bacterial colony types were identified using a combination of methods that include recording characteristics of colony morphology; performing a Gram staining method and metabolic analyses using the Biolog system. Results from one group of bioaerosol samples at the five stations indicate that the sampling duration played an important role in accurately determining bacteria concentration in air samples; there were significant reductions in total bacteria concentrations in the samples collected from ambient stations compared to the sample collected in the layer house; the most prominent bacteria species differed among all five stations and three of the most prominent bacteria from samples taken at all five stations were gram-positive; fungal type differed from station to station. C2 - 2009/// C3 - Proceedings of the American Society of Agricultural and Biological Engineers Annual International Meeting CY - Reno, NV DA - 2009/// PY - 2009/6/21/ DO - 10.13031/2013.28035 PB - American Society of Agricultural and Biological Engineers UR - http://dx.doi.org/10.13031/2013.28035 ER - TY - CONF TI - Measuring Soil Moisture in a Heterogeneous Field AU - Sayde, Chadi AU - Selker, John AU - English, Marshall T2 - World Environmental and Water Resources Congress 2009 AB - This paper explores the theoretical basis, preliminary experimental results and potential benefits of using fiber optic technology for distributed measurement of field soil moisture. This technology determines soil moisture content by measurement of soil thermal response to a heat pulse. With a resolution of 1 m along a fiber optic cable this technique is capable of literally hundreds of measurements along a single cable installed at a specific depth. The technology is still under development at the time of this writing, but the indications are that it can quantify soil water variability with relatively high accuracy at moderate cost. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 CY - Kansas City, MO DA - 2009/5/12/ PY - 2009/5/17/ DO - 10.1061/41036(342)439 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)439 DB - Crossref ER - TY - CONF TI - A Web-Based Advisory Service for Optimum Irrigation Management AU - Hillyer, Charles AU - English, Marshall AU - Abourached, Carole AU - Sayde, Chadi AU - Hutchinson, Kent AU - Busch, John T2 - World Environmental and Water Resources Congress 2009 AB - The optimum (profit maximizing) level of irrigation water use is usually less than the yield maximizing level, particularly when water has an associated opportunity cost. However, the amount of analysis required to implement a profit maximizing strategy is usually too time consuming to be practical for most farmers. Furthermore the practical operational constraints imposed on typical irrigation practices are usually too complicated to be fully encapsulated in software. Oregon State University and the NRCS have cooperatively developed a web-based, user-directed application for optimum irrigation management. This system has already completed two years of field trails and has a demonstrated capacity for delivering conventional irrigation schedules. The system is now entering a second phase of development where we are adding new analytical tools that enable easy generation of optimum irrigation schedules. This system, known as Irrigation Management Online (IMO), explicitly analyzes irrigation efficiency and yield reductions for deficit irrigation, performs simultaneous, conjunctive scheduling for all fields in the farm that share a limited water supply, and employs both ET and soil moisture measurements in a Bayesian decision analysis to enhance the accuracy of the irrigation schedules. To mitigate the complexities of irrigation constraints the system has been designed so that the user is an integral part of the irrigation optimization procedure. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)407 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)407 DB - Crossref ER - TY - JOUR TI - Catalytic ozonation of ammonia using biomass char and wood fly ash AU - Kastner, James R. AU - Miller, Joby AU - Kolar, Praveen AU - Das, K.C. T2 - Chemosphere AB - Catalytic ozonation of gaseous ammonia was investigated at room temperature using wood fly ash (WFA) and biomass char as catalysts. WFA gave the best results, removing ammonia (11 ppmv NH3, 45% conversion) at 23 °C at a residence time of 0.34 s, using 5 g of catalyst or ash at the lowest ozone concentration (62 ppmv). Assuming pseudo zero order kinetics in ozone, a power rate law of -rNH3=7.2×10-8CNH30.25 (r, mol g−1 s−1, CNH3 mol L−1) was determined at 510 ppmv O3 and 23 °C for WFA. Water vapor approximately doubled the oxidation rate using WFA and catalytic ozonation activity was not measured for the char without humidifying the air stream. Overall oxidation rates using the crude catalysts were lower than commercial catalysts, but the catalytic ozonation process operated at significantly lower temperatures (23 vs. 300 °C). Nitric oxide was not detected and the percentage of NO2 formed from NH3 oxidation ranged from 0.3% to 3% (v/v), with WFA resulting in the lowest NO2 level (at low O3 levels). However, we could not verify that N2O was not formed, so further research is needed to determine if N2 is the primary end-product. Additional research is required to develop techniques to enhance the oxidation activity and industrial application of the crude, but potentially inexpensive catalysts. DA - 2009/5// PY - 2009/5// DO - 10.1016/j.chemosphere.2009.01.035 VL - 75 IS - 6 SP - 739-744 J2 - Chemosphere LA - en OP - SN - 0045-6535 UR - http://dx.doi.org/10.1016/j.chemosphere.2009.01.035 DB - Crossref KW - Catalytic ozonation KW - Ammonia KW - Room temperature KW - Wood fly ash KW - Biomass ER - TY - CONF TI - The Use of Soil-Water Sensors in Turf Irrigation Control — How Effective Are They? AU - Grabow, Garry L. AU - Dukes, Michael AU - Thapa, Bir T2 - World Environmental and Water Resources Congress 2009 AB - Soil-Water sensor controllers have been used since the mid-1990s to manage turf irrigation. While evapotranspriation (ET) based controllers have been more widely adopted for turf and landscape irrigation, soil-water-sensor based systems hold some distinct advantages, particularly in humid regions where rainfall contributes significantly to turf water requirements and is highly spatially variable. Some perceived disadvantages of soil-water-sensor based systems are representativeness of whole landscapes when only one sensor is used; sensor accuracy and repeatability, and proper setting of soil-water setpoints. Several studies involving soil-moisture sensors have been done in Florida, and one study in North Carolina is near completion. These studies have looked at soil-water sensor based systems of various manufacturers in similar settings; have compared results between different moisture setting thresholds; have contrasted water usage with ET based controller systems; and have monitored root zone soil-water status in plots irrigated by soil-water based systems. Soil-water data has also been collected for replicates of sensor-based treatments in an effort to address the question of repeatability and sensor placement representativeness. Preliminary data from these studies have shown that there is wide variability between different sensor systems with respect to both applied water and turf quality. The data has also shown that soil water sensor based systems may in some cases apply less water than ET controllers. Consistent relationships between soil-water-content and controller settings has been found to be problematic. Analysis of soil-water data indicates that while there are differences in soil-water between replications of soil-water-based sensor treatments, soil-water trends are generally consistent between replications and turf quality is generally not substantially different between replications. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)433 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)433 DB - Crossref ER - TY - CONF TI - A Level Spreader — Vegetated Buffer System for Urban Stormwater Management AU - Winston, Ryan J. AU - Hunt, William F. T2 - World Environmental and Water Resources Congress 2009 AB - Vegetated filter strips (VFS) have been used to remove pollutants from contributing agricultural watersheds for decades. In order to improve effectiveness of vegetated buffers, level spreaders have been employed to distribute flow evenly across the length of the upstream end of the buffer. In North Carolina, level spreader- VFS systems are now gaining acceptance as a stormwater BMP for urbanized watersheds, as it promotes infiltration and reduces impervious surfaces, two tenets of Low Impact Development. A field study of four level spreader — vegetated filter strip systems was conducted at two urban watersheds in Louisburg and Apex, NC. At each site, stormwater was routed proportionately over two 13 ft long level spreaders, one draining to a 25 ft wide grassed buffer, the other to a 50 ft wide, half grassed, half forested buffer. Flow rates and flow volumes were measured at the inlet and outlets of the system. Composite, flow-weighted water quality samples were collected at the inlet and outlet of the system and analyzed for TKN, NO3+NO2, TN, NH3 TP, Orthophosphate, and TSS. The buffers promoted infiltration, which resulted in a substantial decrease in flow volume and peak flow rate between the inlet and outlet of the system. To date, 46 storm events have been monitored for hydrology in Louisburg, NC. Flow volume was reduced by an average of 83% and 80% for the 25 ft and 50 ft wide buffers, respectively. These buffers also reduced peak flow rate by an average of 86% and 83%, respectively. These results show that a level spreader — vegetated filter strip system can effectively reduce the hydrologic impacts of impervious surfaces. Water quality monitoring has been ongoing since March, 2008, with 19 and 20 storms monitored for Apex and Louisburg, respectively. Reductions in event mean concentrations for all buffer treatments occurred for TKN, TN, and TSS, while the other pollutants studied had mixed results. Because of the large reduction in volume due to infiltration, these BMPs provide a large reduction in mass of pollutants. The median percent mass removal for the Louisburg buffers was greater than 74% for all but one water quality constituent studied. A level spreader is relatively (1) easy to install, (2) inexpensive, and (3) requires little maintenance. Carefully selected and designed level spreader — vegetated buffer systems can be an effective method of controlling stormwater flow and its associated pollutants in small urban watersheds. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)75 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)75 DB - Crossref ER - TY - CONF TI - Bioretention/Bioinfiltration Performance in the Mid-Atlantic AU - Brown, R. A. AU - Hunt, W. F. AU - Davis, A. P. AU - Traver, R. G. AU - Olszewski, J. M. T2 - World Environmental and Water Resources Congress 2009 AB - Researchers in Maryland, North Carolina, and Pennsylvania have been conducting parallel bioretention/bioinfiltration research since fall 2007. Various designs have been tested including those that rely on underdrains, have internal water storage (IWS) layers, or are underdrain-free. The cells provide a range of watershed practice size ratios and employ a variety of land covers. Researchers are pooling water quantity and quality data to help create new design standards. Initial results from the shared data will be presented, with specific attention to bioretention design parameters that control flow modification and water quality improvement. Two bioretention cells of varying vegetative cover are being monitored in Rocky Mount, NC. This site is located in the upper coastal plain with sandy in-situ soils. These cells were designed with a 0.9 m media depth and a 0.6 m deep internal water storage (IWS) layer. Another bioretention cell is being monitored in Silver Spring, MD. It was constructed with a 0.9 m media depth and a 0.3 m pooling depth. Finally, there are two bioinfiltration cells being monitored in Villanova, PA. The first is the "Traffic Island" bioinfiltration cell, which has been monitored since 2003. The bowl is only designed for 1.2 cm over the impervious surface, yet overflow rarely occurs for events less than 5.1 cm. The site had groundwater wells installed in 2007 and is the subject of an ongoing study on the groundwater effects. The second site has only been monitored for approximately six months. Cumulatively, the four bioretention cells extensively examined have dramatically reduced outflow volumes, completely assimilating all events less than 1.2 cm — and in some designs much greater events. By aggregating the data, runoff reduction by bioretention can be profound. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)90 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)90 DB - Crossref ER - TY - CONF TI - An Evaluation of Stormwater Wetlands in Series AU - Hathaway, J. M. AU - Hunt, W. F. T2 - World Environmental and Water Resources Congress 2009 AB - Retrofit BMPs are an important tool for achieving water quality goals in urban watersheds, providing treatment to areas not originally developed with stormwater management practices. One such BMP was installed and monitored in Mooresville, N.C. The system includes three wetlands built "in-series" to treat runoff from a highly impervious 30 acre watershed. The configuration of the wetlands allowed monitoring of water quality parameters at the outlet of each of the three stormwater wetlands. The results of this study indicate that water quality improvement for a number of pollutants experiences diminishing returns as it passes through the three wetland cells. For total suspended solids (TSS), approximately 95% of the total concentration reduction took place in the first wetland cell despite it only comprising 60% of the total surface area of the system. Analysis of the effluent concentrations of the first wetland cell indicates that undersized wetlands (roughly 1.5% of the contributing watershed in this case) may still contribute to water quality improvements in urban watersheds. Thus, retrofit BMPs may be desirable even in circumstances when they cannot be sized appropriately for the contributing watershed. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)82 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)82 DB - Crossref ER - TY - CONF TI - Water Quality Assessed by Benthic Macro-Invertebrates: Proposing the WQABI Method AU - McNett, J. K. AU - Hunt, W. F. T2 - World Environmental and Water Resources Congress 2009 AB - Stormwater experts agree that the currently used percent removal methodology metric has many flaws, and some have suggested utilizing a BMP effluent concentration metric. This paper examines a new method that establishes effluent target concentrations for BMPs based on the health of macro-invertebrates in the receiving water. 193 ambient water quality monitoring stations in North Carolina were paired with benthic macro-invertebrate health ratings collected in very close proximity. Water quality for the sites ranged from Excellent to Poor and was divided into three distinct eco-regions. Median NO3 + NO2, TKN, TN, and TP concentrations all increased with poorer benthic ratings; however, there was no such trend with respect to DO, TSS, and Fecal Coliforms. Overall, the new method was most effective in the Piedmont and Coastal eco-regions; however with more data collection, the Mountain eco-region may also benefit. For example, if regulators were to require "Good" water quality in the Piedmont eco-region, designers would have to limit effluent concentrations of TN and TP would be 0.99 mg/L and 0.11 mg/L, respectively, per the method presented herein. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)542 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)542 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. AU - McCoy, E. R. T2 - World Environmental and Water Resources Congress 2009 AB - Burnt Mill Creek, located within downtown Wilmington, NC, is on the EPA's 303(d) list for impairment due in large part 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. Restoration efforts are multiplying in Burnt Mill Creek as a result of passionate involvement from local community leaders, and partnerships with state organizations. The Watershed Education for Communities and Local Officials (WECO) coordinated a partnership, with NCSU 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. Community involvement has led to several retrofit BMP opportunities, including pervious pavement and rain gardens at a local YMCA, two bioretention cells installed in the parking lot at Port City Java's corporate headquarters, a stormwater wetland in a city owned communal area, and several residential scale rain gardens in an urban low income community. Twelve rain gardens and twenty four rain barrels were installed at citizen's private residences in an urban neighborhood in downtown Wilmington. Although restoration takes time, momentum continues to build in the Burnt Mill Creek watershed as resources are devoted to thoughtful education and engagement with the public. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)536 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)536 DB - Crossref ER - TY - CONF TI - Rainwater Harvesting Experiences in the Humid Southeast USA AU - Jones, Matthew AU - Hunt, William F. AU - Wright, Jason T2 - World Environmental and Water Resources Congress 2009 AB - Due to recent concerns over the environmental impact of stormwater runoff and increased water demands, interest in rainwater harvesting systems as an innovative stormwater treatment practice has developed in humid, well developed regions, such as the southeastern United States. Rainwater harvesting systems are designed to capture runoff from rooftops. The captured water can be used as an alternative to municipal or well water for non-potable applications. The water can be used for irrigation, vehicle washing, toilet flushing, and other non-potable uses. Harvested water can potentially be used for potable uses with proper treatment. Water harvesting systems can reduce peak flows and pollutant loads as well as conserve valuable resources. 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 5 rainwater harvesting systems in North Carolina, measuring cistern water levels and rainfall. Harvested water was used for a variety of applications including vehicle washing, irrigation, and toilet flushing. In order for water harvesting to be a viable solution for stormwater management the harvested water must be used between storm events. The system must be drained as much as possible to provide storage and peak flow mitigation for the next storm event. 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. Research showed that the harvested water may require a dedicated use for water harvesting to be an effective stormwater management tool. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)209 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)209 DB - Crossref ER - TY - CONF TI - Effect of Bioretention on Runoff Temperature in Trout Sensitive Regions AU - Jones, Matthew AU - Hunt, William F. T2 - World Environmental and Water Resources Congress 2009 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 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)156 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)156 DB - Crossref ER - TY - CONF TI - Research of Hydrologic and Water Quality Performance of 4 Linear Wetlands in Eastern North Carolina AU - Wright, J. D. AU - Hunt, W. F. T2 - World Environmental and Water Resources Congress 2009 AB - The North Carolina Department of Transportation is charged by an agreement with the North Carolina Department of Environment and Natural Resources to treat stormwater from NC DOT facilities across North Carolina. One heretofore unaccounted treatment is hundreds of miles of right-of-way swales in eastern North Carolina. It is possible that these serendipitous practices are improving runoff quality along theses highways. If so, an assessment of their performance is needed. Four existing right-of-way linear swales along I–40 east of I–95 will be monitored to determine their hydrologic and water quality effectiveness. Two different treatments are being examined: one swale that is unaltered and one that has been allowed to establish wetland conditions. There are two examples of each. Monitoring will also address the impact of the vegetated filter strip between the shoulder and the edge of the swale. Monitoring began in August of 2008. Samples are being collected from 18 events and analyzed for TN, TKN, NH4—N, NO2–3—N, TP, and TSS. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)148 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)148 DB - Crossref ER - TY - CONF TI - Field Testing Guidelines for Certification of Manufactured Stormwater BMPs: Part II AU - Sansalone, John AU - Benty, Jeff AU - Carrasco, Ernie AU - Gulliver, John AU - Hathaway, Jon AU - Hunt, Bill AU - Kayhanian, Masoud AU - Khambhammettu, Uday AU - Roseen, Robert M. AU - Rushton, Betty AU - Williams, Tim T2 - World Environmental and Water Resources Congress 2009 AB - Guidance from information and field testing concepts examined by the ASCE/EWRI Subcommittee on Field Testing is presented. Field-testing of manufactured treatment devices requires critical planning and implementation through all steps of the verification process from watershed/catchment selection, to testing and analytical protocols, to data evaluation and quality assurance and control measures, to data reporting guidelines. Ultimately the goal of field testing is to provide verification of analytical or numerical models for BMPs that have been developed through scaled or full-scale controlled physical model testing. The desired goals and outcomes must be known and designed into the entire verification process. Ultimately, the entire process leads to a defensible model that represents a quantitative yardstick for both deterministic and probabilistic evaluations of a BMP for stakeholders across a range of regional conditions. This committee is focused on field verification of a BMP for separation of particulate matter (PM) from rainfall-runoff and snowmelt. Towards this goal, the entire gradation of PM requires characterization for a BMP field evaluation, in particular the suspended fraction because of the mobility and acute bio-availability of this finer fraction. On the other hand, the coarse sediment fraction is of particular importance because this coarse fraction fills many BMPs and is most labile. A fundamental, transferable and defensible methodology is considered which includes particle size distributions (PSD) combined with gravimetric index tests for PM: total suspended solids (TSS) and suspended sediment concentration (SSC). TSS by definition is the PM fraction remaining suspended in an Imhoff Cone after one hour, although current methods utilize sub-sampling generate controversy as to the meaning of the measurement. However TSS remains in use because of ubiquitous usage, regulatory significance and as an important index of treatability. In contrast, SSC provides a gravimetric analysis of the entire sample and therefore limited bias, and outstanding reliability and repeatability. Quality assurance and feedback protocol are a necessary part of the testing protocol. We must recognize the range of challenges and collect sufficient representative data within an event and across events so that the role of such uniqueness can be quantified for the specific BMP or BMPs tested. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)113 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)113 DB - Crossref ER - TY - CONF TI - Field Evaluation of Indicator Bacteria Removal by Stormwater BMPs in 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 2009 AB - In the United States Environmental Protection Agency's National Water Quality Inventory in 2000, 13% of the river and stream miles that were surveyed were impaired by pathogen indicator bacteria (USEPA 2002). Stormwater runoff is a transport mechanism for indicator bacteria to receiving waters, resulting in an increased risk to public health through consumption of contaminated shellfish or ingestion by swimmers. Urban stormwater is commonly treated by stormwater Best Management Practices (BMPs), each of which provides some combination of natural treatment mechanisms and fosters certain environmental conditions. Although BMPs have been studied in detail for many pollutants, little peer-reviewed literature is available which documents their ability to remove or inactivate indicator bacteria. The North Carolina State University Department of Biological and Agricultural Engineering evaluated 10 stormwater BMPs in Charlotte and Wilmington, NC, to evaluate their efficiency with respect to indicator bacteria removal. The study practices included two bioretention cells, four stormwater wetlands, two wet ponds, and two dry detention areas. Data collected from these studies indicates that positive removal of indicator bacteria is possible in many types of BMPs; however, removal can be highly variable from practice to practice. Further, stormwater BMPs may foster environments where indicator bacteria can persist, becoming sources of indicator bacteria. Finally, even if positive reductions in indicator bacteria are noted, research indicates that achieving effluent concentrations of indicator bacteria consistent with USEPA standards may be difficult with many types of BMPs. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)112 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)112 DB - Crossref ER - TY - CONF TI - Effects of Media Depth on Bioretention Performance in the Upper Coastal Plain of North Carolina and Bioretention Construction Impacts Study AU - Brown, R. A. AU - Hunt, W. F. T2 - World Environmental and Water Resources Congress 2009 AB - Bioretention is a principal low impact development (LID) practice. This paper examines two critical questions associated with bioretention design and construction. First, fill media is perhaps the major cost in constructing bioretention cells, so shallower media depths would be preferred, were they to work as well as deeper media systems. Two sets of bioretention cells of varying media depths in the upper coastal plain of North Carolina have been monitored since April 2008. They treat an impervious asphalt parking lot watershed in Nashville, NC. The bioretention cells were constructed with media depths of 0.6 and 0.9 m. Performance is being measured with respect to hydrology and water quality. Data show the deeper media depths meet the LID hydrology goal of volume reduction more frequently (35% compared to 9% of 45 events monitored). The second question examines how bioretention cells are excavated. Two excavation techniques, the conventional "scoop" method which purposefully smears the underlying soil surface and the "rake" method which uses the teeth of an excavator's bucket to scarify the underlying soil surface, were tested. Field tests were conducted on three soil types (sand, loamy sand, and clay) and under a variety of antecedent soil moisture conditions. Saturated hydraulic conductivity, surface infiltration, and soil compaction were measured for each excavated condition. In all cases, the rake method of excavation yielded more permeable, less compacted soils than the scoop method. The difference of infiltration and hydraulic conductivity between the two excavation techniques was statistically significant (p<0.05) when tests were conducted in wet soil conditions. Also, the infiltration rate at the clay site was significantly lower (p<0.05), and the hydraulic conductivity at the sandy site was significantly lower (p<0.05), when the scoop methodology was used. Based on results of this experiment and because there is essentially no extra cost associated with the rake method of excavating bioretention cells, the rake method of excavation is recommended over the conventional scoop method. The use of the rake method is expected to increase long term exfiltration from bioretention cells. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)104 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)104 DB - Crossref ER - TY - CONF TI - Data Reporting Guidelines for Certification of Manufactured Stormwater BMPs: Part II 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 2009 AB - Data Reporting guidelines presented here were developed as part of the ASCE/EWRI Task Committee on Guidelines for Certification of Manufactured Stormwater BMPs. This work is the collaboration of the Stormwater Infrastructure Committee of EWRI's Water, Wastewater, and Stormwater Council (WWSC) and the Wet Weather Flow Technology Committee of the Urban Water Resources Research Council (UWRRC). These guidelines were developed by review of the major manufactured treatment device certification protocol requirements drawing primarily from the Technology Assessment Protocol-Ecology (TAPE) and the Technology Assessment Reciprocity Partnership (TARP). These reporting guidelines have been broadened to support the International Stormwater Best Management Practices (BMP) Database. With the increasing need for the field testing of proprietary devices comes the importance of consistent data reporting guidelines to be used when reporting to regulatory agencies or designers. The need for standardized reporting is underscored by the tremendous impact the range of testing factors can have upon testing results. These factors include the testing environment, experimental design, testing methodologies, statistical analysis, and data presentation. The need for 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. A consistent reporting format is also needed to aid vendors to efficiently navigate the complicated application process for device certification. Finally, an independent third-party is needed to either conduct or review the testing to ensure testing impartiality. The committee membership includes stakeholders from the regulatory, academic, manufacturing, and design communities. C2 - 2009/5/12/ C3 - World Environmental and Water Resources Congress 2009 DA - 2009/5/12/ DO - 10.1061/41036(342)100 PB - American Society of Civil Engineers SN - 9780784410363 UR - http://dx.doi.org/10.1061/41036(342)100 DB - Crossref ER - TY - RPRT TI - Role of Directly Connected Macropores on Pathogen Transport to Subsurface Drainage Water AU - Hoang, Chi Kim AU - Pederson, Carl H. AU - Kanwar, Rameshwar S. AU - Fox, Garey A3 - Iowa State University, Digital Repository C6 - RFR-A9116 DA - 2009/// PY - 2009/// DO - 10.31274/farmprogressreports-180814-1242 M1 - RFR-A9116 M3 - Iowa State Research Farm Progress Reports PB - Iowa State University, Digital Repository SN - RFR-A9116 UR - http://dx.doi.org/10.31274/farmprogressreports-180814-1242 ER - TY - JOUR TI - Predicting the temperature dependent viscosity of biodiesel fuels AU - Yuan, W. AU - Hansen, A.C. AU - Zhang, Q. T2 - Fuel AB - The purpose of this work was to develop a method for predicting temperature dependent viscosities of biodiesel based on fatty acid ester composition. The Grunberg–Nissan equation combined with a group contribution method was used as the mixing rule to calculate viscosities of mixtures of fatty acid esters. Prediction errors at 25 °C were less than 2.5% for 22 mixtures of fatty acid ethyl esters. Compared with experimentally measured viscosities at 20–100 °C, predicted viscosities of soybean oil and yellow grease methyl esters were within 3%. For coconut, palm and canola oil methyl esters, maximum errors were underestimations at approximately 7%. DA - 2009/6// PY - 2009/6// DO - 10.1016/j.fuel.2008.11.011 VL - 88 IS - 6 SP - 1120-1126 J2 - Fuel LA - en OP - SN - 0016-2361 UR - http://dx.doi.org/10.1016/j.fuel.2008.11.011 DB - Crossref KW - Biodiesel KW - Esters KW - Viscosity ER - TY - JOUR TI - Microbiological and biochemical changes during processing of the traditional chinese food douzhi AU - Ding, Yu-Zhen AU - Zhang, Shao-Ying AU - Liu, Peng AU - Yuan, Wenqiao AU - Liang, Jin-Yi AU - Zhao, Zhe AU - Zhang, Yu-Dong T2 - Food Control AB - The microbiological and biochemical changes during douzhi processing were studied. The sedimentation process was shown to follow a lactic fermentation course. The main fermenting bacteria were identified to be Lactococcus lactis and Leuconostoc citreum; the former played the main role in producing acids, and the latter ensured a better flavor of douzhi. Yeasts thrived during the late part of fermentation were believe to account for the decrease in acidity. Tracing the change of chemical compounds suggested that active metabolic activity was induced when beans were steeped in water, in which significant reduction in crude protein and sugars were observed, but levels of soluble proteins, free amino acids increased. Fermentation by lactic acid bacteria caused a rapid reduction of soluble proteins, soluble sugars and reducing sugars, but significant accumulation of free amino acids and slight changes in crude protein. Mung bean endogenous protease and amylase activity dropped significantly during fermentation. DA - 2009/12// PY - 2009/12// DO - 10.1016/j.foodcont.2009.02.005 VL - 20 IS - 12 SP - 1086-1091 J2 - Food Control LA - en OP - SN - 0956-7135 UR - http://dx.doi.org/10.1016/j.foodcont.2009.02.005 DB - Crossref KW - Mung bean KW - Lactococcus lactis KW - Leuconostoc citreum ER - TY - JOUR TI - Heterotrophic Culture of Chlorella protothecoides in Various Nitrogen Sources for Lipid Production AU - Shen, Y. AU - Yuan, W. AU - Pei, Z. AU - Mao, E. T2 - Applied Biochemistry and Biotechnology DA - 2009/5/8/ PY - 2009/5/8/ DO - 10.1007/S12010-009-8659-Z VL - 160 IS - 6 SP - 1674-1684 J2 - Appl Biochem Biotechnol LA - en OP - SN - 0273-2289 1559-0291 UR - http://dx.doi.org/10.1007/S12010-009-8659-Z DB - Crossref KW - Algae KW - Biofuel KW - Nitrogen KW - Chlorella protothecoides KW - Lipid ER - TY - CONF TI - Use of bioengineered artificial reefs for ecological restoration in estuarine environments AU - Hall, S.G. AU - Dehon, D. AU - Ortego, T. AU - Beine, R. AU - Campbell, M. AU - Turley, M. C2 - 2009/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2009, ASABE 2009 DA - 2009/// VL - 4 SP - 2445-2454 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-76449091263&partnerID=MN8TOARS ER - TY - CONF TI - Design of a communications system between multiple autonomous vehicles AU - Hall, S.G. AU - Smith, D.D. AU - Davis, T. C2 - 2009/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2009, ASABE 2009 DA - 2009/// VL - 9 SP - 5826-5834 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-77649150293&partnerID=MN8TOARS ER - TY - CONF TI - Using MODFLOW to compare management alternatives for a river alluvial aquifer AU - Mittelstet, A. AU - Smolen, M. AU - Fox, G. C2 - 2009/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2009, ASABE 2009 DA - 2009/// VL - 9 SP - 5917-5928 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-77649083165&partnerID=MN8TOARS ER - TY - JOUR TI - Subsurface transport of phosphorus in riparian floodplains: Influence of preferential flow paths AU - Fuchs, J.W. AU - Fox, G.A. AU - Storm, D.E. AU - Penn, C.J. AU - Brown, G.O. T2 - Journal of Environmental Quality AB - For phosphorus (P) transport from upland areas to surface water systems, the primary transport mechanism is typically considered to be 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 potential of subsurface transport of P along streams characterized by cherty or gravel subsoils, especially the impact of preferential flow paths on P transport. At a field site along the Barren Fork Creek in northeastern Oklahoma, a trench was installed with the bottom at the topsoil/alluvial gravel interface. Fifteen piezometers were installed surrounding the trench to monitor flow and transport. In three 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 solution were injected into the trench at concentrations at 3 and 100 mg/L for Rhodamine WT and at 100 mg/L for P. Laboratory flow‐cell experiments were also conducted on soil material <2 mm in size to determine the effect that flow velocity had on P sorption. Rhodamine WT and P were detected in some piezometers at equivalent concentrations as measured in the trench, suggesting the presence of preferential flow pathways and heterogeneous interaction between streams and subsurface transport pathways, even in nonstructured, coarse gravel soils. Phosphorus transport was retarded in nonpreferential flow paths. Breakthrough times were approximately equivalent for Rhodamine WT and P suggesting no colloidal‐facilitated P transport. Results from laboratory flow‐cell experiments suggested that higher velocity resulted in less P sorption for the alluvial subsoil. Therefore, differences in flow rates between preferential and nonpreferential flow pathways in the field led to variable sorption. The potential for nutrient subsurface transport shown by this alluvial system has implications regarding management of similar riparian floodplain systems. DA - 2009/// PY - 2009/// DO - 10.2134/jeq2008.0201 VL - 38 IS - 2 SP - 473-484 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-63449114948&partnerID=MN8TOARS ER - TY - CONF TI - Predicting streambank seepage flows: Sensitivity to soil properties and layering AU - Heeren, D.M. AU - Fox, G.A. AU - Chu-Agor, M.L. AU - Wilson, G.V. AB - Streambank failures result in loss of land and increased stream sediment loads. Variably saturated flow models integrated with bank stability models are being used to predict bank failure; however, understanding of the level of soil characterization necessary to predict when seepage contributes to bank failure is needed. ROSETTA, a pedotransfer function, was used to estimate hydraulic parameters for various levels of soil data (from texture class to saturated hydraulic conductivity, Ks). A two-dimensional groundwater flow code, SEEP/W, was used to model a hypothetical streambank and estimate seepage velocity. Results suggested that Ks and/or percent clay measurements are necessary to adequately predict seepage. A layered bank was also simulated with several combinations of soil types. Results indicated that only one order of magnitude difference in Ks (equivalent to a resistance ratio of 10) may be necessary to induce perching and seepage from the top layer. This research suggested that, if a field reconnaissance is performed to locate streambanks susceptible to perching, Ks and/or bulk density measurements are necessary to indicate the presence of a restrictive layer. C2 - 2009/// C3 - Proceedings of World Environmental and Water Resources Congress 2009 - World Environmental and Water Resources Congress 2009: Great Rivers DA - 2009/// DO - 10.1061/41036(342)377 VL - 342 SP - 3753-3762 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-70350139520&partnerID=MN8TOARS ER - TY - JOUR TI - Escherichia coli transport from surface-applied manure to subsurface drains through artificial biopores AU - Guzman, J.A. AU - Fox, G.A. AU - Malone, R.W. AU - Kanwar, R.S. T2 - Journal of Environmental Quality AB - Bacteria transport in soils primarily occurs through soil mesopores and macropores (e.g., biopores and cracks). Field research has demonstrated that biopores and subsurface drains can be hydraulically connected. This research was conducted to investigate the importance of surface connected and disconnected (buried) biopores on Escherichia coli ( E. coli ) transport when biopores are located near subsurface drains. A soil column (28 by 50 by 95 cm) was packed with loamy sand and sandy loam soils to bulk densities of 1.6 and 1.4 Mg m −3 , respectively, and containing an artificial biopore located directly above a subsurface drain. The sandy loam soil was packed using two different methods: moist soil sieved to 4.0 mm and air‐dried soil manually crushed and then sieved to 2.8 mm. A 1‐cm constant head was induced on the soil surface in three flushes: (i) water, (ii) diluted liquid swine ( Sus scrofa ) manure 48 h later, and (iii) water 48 h after the manure. Escherichia coli transport to the drain was observed with either open surface connected or buried biopores. In surface connected biopores, E. coli transport was a function of the soil type and the layer thickness between the end of the biopore and drain. Buried biopores contributed flow and E. coli in the less sorptive soil (loamy sand) and the sorptive soil (sandy loam) containing a wide (i.e., with mesopores) pore space distribution prevalent due to the moist soil packing technique. Biopores provide a mechanism for rapidly transporting E. coli into subsurface drains during flow events. DA - 2009/// PY - 2009/// DO - 10.2134/jeq2009.0077 VL - 38 IS - 6 SP - 2412-2421 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-70350706102&partnerID=MN8TOARS ER - TY - CONF TI - Sorption of E. coli from liquid swine manure in natural and artificial soils AU - Guzmán, J.A. AU - Fox, G. AU - Penn, C. C2 - 2009/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2009, ASABE 2009 DA - 2009/// VL - 5 SP - 3094-3104 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-76549101418&partnerID=MN8TOARS ER - TY - JOUR TI - Sorption of E. coli from liquid swine manure in natural and artificial soils AU - Guzman, Jorge A AU - Fox, Garey A AU - Penn, Chad J T2 - 2009 Reno, Nevada, June 21 - June 24, 2009 AB - Animal waste applications in agricultural lands can contribute microbial contamination to water bodies. After manure application, Escherichia Coli (E. coli) can be transported by surface runoff and infiltration or can be retained in soils by its filter capacity. The soil filter capacity is a dynamic function of the physical-chemical properties of the soil, effluent composition and bacteria properties. In this study, E. coli isotherms were determined after mixing natural and artificial soils with manure effluents at different dilution ratios and decanting the clay particles by centrifugation. Two natural soils (e.g., loamy sand and sandy loam) and seven artificial soils were used with different clay (e.g., kaolinite: KGa-1) and organic matter (e.g., Sphagnum peat moss) content. In addition, the organic matter in the natural soils was removed using a hydrogen peroxide reagent. Sorption data fit a nonlinear Freundlich isotherm with a coefficient of determination, R2, higher than 0.93 except for the pure sand and natural soils after the organic matter was removed (e.g., R2 was higher than 0.84). Sorption data suggested that the presence of organic matter favored E. coli sorption in soils with clay contents lower than 10%. Sorption equations based on clay content without considering the effect of organic matter may underestimate E. coli sorption for varying solution E. coli concentrations. A general equation to estimate the Freundlich coefficients were obtained from the experiments based on the natural logarithms of clay content for total carbon content in the range of 0 to 2.1%. These equations are intended to be valuable in estimating E. coli sorption in manure-amended soils for improved modeling of E. coli fate and transport in soils. DA - 2009/// PY - 2009/// DO - 10.13031/2013.27091 ER - TY - CONF TI - Preferential flow path effects on subsurface contaminant transport in alluvial floodplains AU - Heeren, D.M. AU - Miller, R.B. AU - Fox, G.A. AU - Storm, D.E. AU - Penn, C.J. AU - Halihan, T. C2 - 2009/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2009, ASABE 2009 DA - 2009/// VL - 4 SP - 2167-2176 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-76449101727&partnerID=MN8TOARS ER - TY - CONF TI - Incorporating seepage processes into a streambank stability model AU - Chu-Agor, M.L. AU - Fox, G.A. AU - Wilson, G. C2 - 2009/// C3 - American Society of Agricultural and Biological Engineers Annual International Meeting 2009, ASABE 2009 DA - 2009/// VL - 3 SP - 1769-1779 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-76549083520&partnerID=MN8TOARS ER - TY - JOUR TI - Preferential Flow Path Effects on Subsurface Contaminant Transport in Alluvial Floodplains AU - Heeren, Derek M AU - Miller, Ron B AU - Fox, Garey A AU - Storm, Daniel E AU - Penn, Chad J AU - Halihan, Todd T2 - 2009 Reno, Nevada, June 21 - June 24, 2009 AB - For strongly sorbing contaminants, transport from upland areas to surface water systems is typically considered to be due to surface runoff with subsurface transport assumed negligible. However, certain local conditions can lead to an environment where subsurface transport to streams may be significant, a source of contamination not alleviated by current best management practices (e.g. riparian buffers). The Ozark region, including parts of Oklahoma, Arkansas, and Missouri, is characterized by cherty, gravelly soils and gravel bed streams. Previous research identified a preferential flow path (PFP) at a field site along the Barren Fork Creek in northeastern Oklahoma. With the subsoils having hydraulic conductivities on the order of 100 to 500 m/d, the previous research demonstrated that even a sorbing contaminant such as phosphorus can be transported in significant quantities through the subsurface. The objective of the current project was to determine the connectivity of the PFP to the stream and to further evaluate the hypothesis that the alluvial groundwater acts as a transient storage zone, providing a contaminant sink during high flow and a contaminant source during baseflow. A trench was installed above the PFP with the bottom of the trench at the topsoil/alluvial gravel interface. Piezometers were installed along the PFP and throughout the riparian floodplain, which was mapped with electrical resistivity equipment. Water was pumped into the trench to maintain a constant head, and a conservative tracer (Rhodamine WT) was injected into the trench. Water table elevations were recorded real-time using water level loggers and water samples were collected throughout the experiment. Results of the experiment demonstrated preferential movement of Rhodamine WT along the perched preferential flow pathway, infiltration of Rhodamine WT into the alluvial groundwater system, and then transport in the alluvial system as influenced by the stream/aquifer dynamics. This research demonstrated the importance of physical heterogeneity in affecting contaminant transport even in coarse gravel, alluvial subsoils. DA - 2009/// PY - 2009/// DO - 10.13031/2013.27025 ER - TY - JOUR TI - Incorporating Seepage Processes into a Streambank Stability Model AU - Chu-Agor, Maria AU - Fox, Garey A AU - Wilson, Glenn V T2 - 2009 Reno, Nevada, June 21 - June 24, 2009 AB - Seepage processes are usually neglected in bank stability analyses although they can become a prominent failure mechanism under certain field conditions. This study incorporated the effects of seepage (i.e., seepage gradient forces and seepage erosion undercutting) into the Bank Stability and Toe Erosion Model (BSTEM) and evaluated the importance of the seepage mechanisms on bank stability. The effects of the seepage force were incorporated into BSTEM by modifying the force balance. Seepage erosion undercutting was simulated using a recently proposed sediment transport function. The modified BSTEM was then used to evaluate the stability of a streambank along Little Topashaw Creek under different scenarios: (1) without seepage forces and undercutting, (2) with seepage forces only, (3) with seepage undercutting only, and (4) with both seepage forces and undercutting. For a condition where the bank was fully saturated, the factor of safety (FS) decreased by as much as 66% (i.e., FS decreased from 2.68 to 0.91) from that of a dry condition due to the decrease in the frictional strength of the soil as the pore-water pressure increased. Incorporating the effects of the seepage force resulted in an average decrease in the FS of approximately 30 to 50% for all water table depths. Seepage erosion undercutting reduced the FS by approximately 6% for a 5 cm undercut (i.e., 2% of the bank height) and 11% for a 10 cm undercut (i.e., 3.3% of the bank height) due to the loss of supporting material in the conductive layer. Seepage erosion undercutting required 15 to 20 cm of seepage undercut to become the dominant failure mechanism over seepage forces and pore-water pressure effects. The cumulative effects of seepage reduced this streambanks FS by up to 63% when the water table reached the entire bank height. The development of a bank stability model capable of simulating seepage processes was necessary in order to better understand site-specific failure mechanisms. DA - 2009/// PY - 2009/// DO - 10.13031/2013.27001 ER - TY - CONF TI - A seepage erosion sediment transport function and geometric headcut relationships for predicting seepage erosion undercutting AU - Chu-Agor, M.L. AU - Fox, G.A. AU - Wilson, G.V. AB - Seepage erosion is an important factor in hillslope instability and failure. However, predicting erosion by subsurface flow or seepage and incorporating its effects into stability models remain a challenge. Limitations exist with all existing seepage erosion sediment transport functions, including neglecting the three-dimensional geometry of the seepage undercut. The objective was to develop a sediment transport model that can predict sediment mobilization (i.e., seepage erosion and undercutting) with time based on previously reported three-dimensional soil block experiments covering a wide range of hydraulic, soil type, and packing (i.e., slope and bulk density) combinations. The transport function was represented by an excess velocity equation wherein the rate of erosion was related to the difference between the steady state velocity and the critical velocity (R2 = 0.62). The critical velocity was derived from a critical head measured in the laboratory using the three-dimensional soil block. The relationship between the eroded volume per bank face area and the amplitude of the headcut was also derived. Using a three-dimensional Gaussian function, the geometric relationships between the lateral and vertical dimensions of the headcut were then estimated. Linear regression analysis between the predicted and observed time at which a given amount of headcut developed resulted in an R2 of 0.86. The ground water velocity exfiltrating a hillslope can be used with the derived sediment transport function to predict the dimensions of the headcut and the geometry of the undercut which enables the prediction of the impact of seepage erosion undercutting on hillslope stability. C2 - 2009/// C3 - Proceedings of World Environmental and Water Resources Congress 2009 - World Environmental and Water Resources Congress 2009: Great Rivers DA - 2009/// DO - 10.1061/41036(342)378 VL - 342 SP - 3763-3772 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-70350164430&partnerID=MN8TOARS ER - TY - JOUR TI - Empirical sediment transport function predicting seepage erosion undercutting for cohesive bank failure prediction AU - Chu-Agor, M.L. AU - Fox, G.A. AU - Wilson, G.V. T2 - Journal of Hydrology AB - Seepage erosion is an important factor in hillslope instability and failure. However, predicting erosion by subsurface flow or seepage and incorporating its effects into stability models remains a challenge. Limitations exist with all existing seepage erosion sediment transport functions, including neglecting the three-dimensional geometry of the seepage undercut and the cohesive nature of soils. The objective was to develop an empirical sediment transport function that can predict seepage erosion and undercutting with time based on three-dimensional soil block experiments covering a wide range of hydraulic, soil type, slope and bulk density combinations. The transport function was represented by an excess gradient equation (R2 = 0.54). The critical gradient was predicted by the soil cohesion based on laboratory experiments. Using a three-dimensional Gaussian function, the geometric relationships between the maximum distance and lateral and vertical dimensions of the undercut were then derived. The proposed empirical relationships reasonably predicted the observed volume per unit area of undercut, erosion rate, and time at which a given amount of undercut developed. The flow gradient can be used with the derived sediment transport function, the first ever relationship proposed for predicting the dimensions and the geometry of the undercut, to predict the impact of seepage erosion undercutting on hillslope stability. Users only need to input the seepage layer’s cohesion, bulk density, and the hydraulic gradient over time in the near-bank ground water system. DA - 2009/// PY - 2009/// DO - 10.1016/j.jhydrol.2009.08.020 VL - 377 IS - 1-2 SP - 155-164 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-70349289822&partnerID=MN8TOARS KW - Seepage KW - Ground water flow KW - Erosion KW - Sediment transport KW - Bank stability ER - TY - JOUR TI - Effectiveness of vegetative filter strips in reducing pesticide loading: Quantifying pesticide trapping efficiency AU - Sabbagh, G.J. AU - Fox, G.A. AU - Kamanzi, A. AU - Roepke, B. AU - Tang, J.-Z. T2 - Journal of Environmental Quality AB - Pesticide trapping efficiency of vegetated filter strips (VFS) is commonly predicted with low success using empirical equations based solely on physical characteristics such as width and slope. The objective of this research was to develop and evaluate an empirical model with a foundation of VFS hydrological, sedimentological, and chemical specific parameters. The literature was reviewed to pool data from five studies with hypothesized significant parameters: pesticide and soil properties, percent reduction in runoff volume (i.e., infiltration) and sedimentation, and filter strip width. The empirical model was constructed using a phase distribution parameter, defined as the ratio of pesticide mass in dissolved form to pesticide mass sorbed to sediment, along with the percent infiltration, percent sedimentation, and the percent clay content ( R 2 = 0.86 and standard deviation of differences [STDD] of 7.8%). Filter strip width was not a statistically significant parameter in the empirical model. For low to moderately sorbing pesticides, the phase distribution factor became statistically insignificant; for highly sorbing pesticides, the phase distribution factor became the most statistically significant parameter. For independent model evaluation datasets, the empirical model based on infiltration and sediment reduction, the phase distribution factor, and the percent clay content (STDD of 14.5%) outperformed existing filter strip width equations (STDD of 38.7%). This research proposed a procedure linking a VFS hydrologic simulation model with the proposed empirical trapping efficiency equation. For datasets with sufficient information for the VFS modeling, the linked numerical and empirical models significantly ( R 2 = 0.74) improved predictions of pesticide trapping over empirical equations based solely on physical VFS characteristics. DA - 2009/// PY - 2009/// DO - 10.2134/jeq2008.0266 VL - 38 IS - 2 SP - 762-771 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-58349121897&partnerID=MN8TOARS ER - TY - JOUR TI - Comment on "major factors influencing the efficacy of vegetated buffers on sediment trapping: A review and analysis," by Xingmei Liu, Xuyang Zhang, and Minghua Zhang the Journal of Environmental Quality 2008 37:1667-1674 AU - Fox, G.A. AU - Sabbagh, G.J. T2 - Journal of Environmental Quality AB - Journal of Environmental QualityVolume 38, Issue 1 p. 1-3 Letter to the Editor Comment on “Major Factors Influencing the Efficacy of Vegetated Buffers on Sediment Trapping: A Review and Analysis,” by Xingmei Liu, Xuyang Zhang, and Minghua Zhang in the Journal of Environmental Quality 2008 37:1667–1674 Garey A. Fox, Corresponding Author Garey A. Fox garey.fox@okstate.edu Dep. of Biosystems and Agricultural Engineering, Oklahoma State Univ., Stillwater, OK, 74074garey.fox@okstate.edu, george.sabbagh@bayercropscience.comSearch for more papers by this authorGeorge J. Sabbagh, Corresponding Author George J. Sabbagh george.sabbagh@bayercropscience.com Bayer CropScience and Texas A&M Univ., 17745 South Metcalf, Stilwell, KS, 66085garey.fox@okstate.edu, george.sabbagh@bayercropscience.comSearch for more papers by this author Garey A. Fox, Corresponding Author Garey A. Fox garey.fox@okstate.edu Dep. of Biosystems and Agricultural Engineering, Oklahoma State Univ., Stillwater, OK, 74074garey.fox@okstate.edu, george.sabbagh@bayercropscience.comSearch for more papers by this authorGeorge J. Sabbagh, Corresponding Author George J. Sabbagh george.sabbagh@bayercropscience.com Bayer CropScience and Texas A&M Univ., 17745 South Metcalf, Stilwell, KS, 66085garey.fox@okstate.edu, george.sabbagh@bayercropscience.comSearch for more papers by this author First published: 01 January 2009 https://doi.org/10.2134/jeq2009.0001leCitations: 20 All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume38, Issue1January 2009Pages 1-3 RelatedInformation DA - 2009/// PY - 2009/// DO - 10.2134/jeq2009.0001le VL - 38 IS - 1 SP - 1-2 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-58349093105&partnerID=MN8TOARS ER - TY - JOUR TI - Chlorpyrifos and atrazine removal from runoff by vegetated filter strips: Experiments and predictive modeling AU - Poletika, N.N. AU - Coody, P.N. AU - Fox, G.A. AU - Sabbagh, G.J. AU - Dolder, S.C. AU - White, J. T2 - Journal of Environmental Quality AB - Runoff volume and flow concentration are hydrological factors that limit effectiveness of vegetated filter strips (VFS) in removing pesticides from surface runoff. Empirical equations that predict VFS pesticide effectiveness based solely on physical characteristics are insufficient on the event scale because they do not completely account for hydrological processes. This research investigated the effect of drainage area ratio (i.e., the ratio of field area to VFS area) and flow concentration (i.e., uniform versus concentrated flow) on pesticide removal efficiency of a VFS and used these data to provide further field verification of a recently proposed numerical/empirical modeling procedure for predicting removal efficiency under variable flow conditions. Runoff volumes were used to simulate drainage area ratios of 15:1 and 30:1. Flow concentration was investigated based on size of the VFS by applying artificial runoff to 10% of the plot width (i.e., concentrated flow) or the full plot width (i.e., uniform flow). Artificial runoff was metered into 4.6‐m long VFS plots for 90 min after a simulated rainfall of 63 mm applied over 2 h. The artificial runoff contained sediment and was dosed with chlorpyrifos and atrazine. Pesticide removal efficiency of VFS for uniform flow conditions (59% infiltration; 88% sediment removal) was 85% for chlorpyrifos and 62% for atrazine. Flow concentration reduced removal efficiencies regardless of drainage area ratio (i.e., 16% infiltration, 31% sediment removal, 21% chlorpyrifos removal, and 12% atrazine removal). Without calibration, the predictive modeling based on the integrated VFSMOD and empirical hydrologic‐based pesticide trapping efficiency equation predicted atrazine and chlorpyrifos removal efficiency under uniform and concentrated flow conditions. Consideration for hydrological processes, as opposed to statistical relationships based on buffer physical characteristics, is required to adequately predict VFS pesticide trapping efficiency. DA - 2009/// PY - 2009/// DO - 10.2134/jeq2008.0404 VL - 38 IS - 3 SP - 1042-1052 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-66649116382&partnerID=MN8TOARS ER - TY - JOUR TI - E. coli transport through soil columns: Implications for bioretention cell removal efficiency AU - Garbrecht, K. AU - Fox, G.A. AU - Guzman, J.A. AU - Alexander, D. T2 - Transactions of the ASABE DA - 2009/// PY - 2009/// VL - 52 IS - 2 SP - 481-486 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-67049155673&partnerID=MN8TOARS ER - TY - JOUR TI - Incertitudes sur les métriques de qualité des cours d'eau (médianes et quantiles de concentrations, flux, cas des nutriments) évaluées a partir de suivis discrets AU - Moatar, Florentina AU - Birgand, François AU - Meybeck, Michel AU - Faucheux, C. AU - Raymond, S. T2 - La Houille Blanche AB - L'évaluation de la qualité des cours d'eau est réalisée à partir de deux principaux types d'indicateurs : les concentrations annuelles (moyennes arithmétiques (Cmoy), médianes (C50), quantiles supérieurs (C90), moyennes pondérées par les débits, (C*..) qui sont rapportées à une grille de qualité (SEQ-Eau) et les flux annuels ramenés généralement à la surface du bassin versant productrice. Ces indicateurs sont entachés d'une incertitude, rarement quantifiée, qui dépend d'abord de la variabilité des concentrations des différents constituents avec la saison et les débits, de la variabilité hydrologique et du nombre de mesures N/an. C'est la spécificité du programme VARIFLUX soutenu par le programme ECCO-ANR/INSU/CNRS dont les résultats sont présentés ici. DA - 2009/6// PY - 2009/6// DO - 10.1051/lhb/2009029 VL - 6 IS - 3 SP - 68-76 J2 - La Houille Blanche OP - SN - 0018-6368 1958-5551 UR - http://dx.doi.org/10.1051/lhb/2009029 DB - Crossref ER - TY - JOUR TI - Genetic Control of Photoperiod Sensitivity in Maize Revealed by Joint Multiple Population Analysis AU - Coles, N. D. AU - McMullen, M. D. AU - Balint-Kurti, P. J. AU - Pratt, R. C. AU - Holland, J. B. T2 - Genetics AB - Abstract Variation in maize for response to photoperiod is related to geographical adaptation in the species. Maize possesses homologs of many genes identified as regulators of flowering time in other species, but their relation to the natural variation for photoperiod response in maize is unknown. Candidate gene sequences were mapped in four populations created by crossing two temperate inbred lines to two photoperiod-sensitive tropical inbreds. Whole-genome scans were conducted by high-density genotyping of the populations, which were phenotyped over 3 years in both short- and long-day environments. Joint multiple population analysis identified genomic regions controlling photoperiod responses in flowering time, plant height, and total leaf number. Four key genome regions controlling photoperiod response across populations were identified, referred to as ZmPR1–4. Functional allelic differences within these regions among phenotypically similar founders suggest distinct evolutionary trajectories for photoperiod adaptation in maize. These regions encompass candidate genes CCA/LHY, CONZ1, CRY2, ELF4, GHD7, VGT1, HY1/SE5, TOC1/PRR7/PPD-1, PIF3, ZCN8, and ZCN19. DA - 2009/// PY - 2009/// DO - 10.1534/genetics.109.110304 VL - 184 IS - 3 SP - 799-812 ER - TY - JOUR TI - Maize Disease Resistance AU - Balint-Kurti, Peter J. AU - Johal, Gurmukh S. T2 - Handbook of Maize: Its Biology AB - This chapter presents a selective view of maize disease resistance to fungal diseases, highlighting some aspects of the subject that are currently of significant interest or that we feel have been under-investigated. These include: DA - 2009/// PY - 2009/// DO - 10.1007/978-0-387-79418-1_12 SP - 229-250 ER - TY - JOUR TI - Developments in mycotoxin analysis: an update for 2007-2008 AU - Shephard, G. S. AU - Berthiller, F. AU - Dorner, J. AU - Krska, R. AU - Lombaert, G. A. AU - Malone, B. AU - Maragos, C. AU - Sabino, M. AU - Solfrizzo, M. AU - Trucksess, M. W. AU - Egmond, H. P. AU - Whitaker, T. B. T2 - WORLD MYCOTOXIN JOURNAL AB - This review highlights developments in mycotoxin analysis and sampling over a period between mid-2007 and mid-2008. It covers the major mycotoxins: aflatoxins, Alternaria toxins, cyclopiazonic acid, fumonisins, ochratoxin, patulin, trichothecenes, and zearalenone. Some aspects of natural occurrence, particularly if linked to novel aspects of analytical methods, are also included. The review demonstrates the rise of LC-MS methods, the continuing interest in developing alternative and rapid methods and the modification of well-established mycotoxin analytical methods by individual laboratories to meet their own requirements. DA - 2009/2// PY - 2009/2// DO - 10.3920/wmj2008.1095 VL - 2 IS - 1 SP - 3-21 SN - 1875-0796 KW - aflatoxin KW - Alternaria toxins KW - cyclopiazonic acid KW - ergot KW - fumonisin KW - ochratoxin KW - patulin KW - trichothecenes KW - zearalenone KW - sampling ER - TY - CONF TI - Automated tractor guidance and implement tracking error assessment AU - Veal, M. W. AU - Shearer, S. A. AU - Stombaugh, T. S. AU - Luck, J. D. AU - Koostra, B. K. C2 - 2009/// C3 - Conference: agricultural engineering - land-technik ageng 2009 - innovations to meet future challenges DA - 2009/// SP - 193-198 M1 - 2060 ER - TY - JOUR TI - Water quality improvements using modified sediment control systems on construction sites AU - McLaughlin, R. A. AU - Hayes, S. A. AU - Clinton, D. L. AU - McCaleb, M. S. AU - Jennings, G. D. T2 - Transactions of the ASABE AB - A study of the water quality of discharges from three different sediment control systems was conducted on a large construction site in North Carolina. Samples were obtained during storm events at the outlets of 11 of these systems using automatic samplers. Turbidity and total suspended solids (TSS) were measured, and a storm-weighted average (SWA) was determined for the systems. Water discharged from five standard sediment traps with rock dam outlets and unlined diversion ditches with rock check dams had an SWA turbidity of 4,320 nephelometric turbidity units (NTU) and an SWA peak of 12,640 NTU over a total of 26 storm events. The representative TSS values were 4,130 and 11,800 mg L-1, respectively. Measurements of runoff entering and exiting the traps suggested that heavy sediment was being captured, but turbidity was not reduced. Three traps with modifications including forebays, porous baffles, improved ditch stabilization (lining, additional check dams), and polyacrylamide application had SWA and peak turbidity of 990 and 1,580 NTU, respectively, over a total of 31 events. Total suspended solids were also much lower, at 740 and 1,810 mg L-1, respectively. Three basins with these same modifications, but with surface outlets, had somewhat higher average SWA values (1,560 NTU, 820 mg L-1), suggesting that the outlet type may not improve discharge water quality above the benefits of the other modifications to the standard sediment trap. However, when one of the latter systems was at optimal function, turbidity was reduced to below the receiving stream water levels (<100 NTU). These results strongly suggest that relatively simple modifications of commonly employed sediment trapping systems can dramatically improve discharge water quality and reduce the impacts on receiving waters. DA - 2009/// PY - 2009/// DO - 10.13031/2013.29214 VL - 52 IS - 6 SP - 1859-1867 ER - TY - JOUR TI - Impact of land application method on ammonia loss from hog lagoon effluent AU - Shah, Sanjay AU - Balla, B. K. AU - Grabow, G. L. AU - Westerman, P. W. AU - Bailey, D. E. T2 - Applied Engineering in Agriculture AB - Ammonia volatilization during land-application of hog lagoon effluent can adversely affect public health and the environment. Ammonia losses from hog lagoon effluent applied to Coastal Bermudagrass with the drag-hose (two applications) and traveling gun (three applications) were measured in spring and summer of 2006. Ammonia losses during application with the traveling gun were measured with acidified catch cans while losses during (traveling gun) or following (drag-hose) application for up to 96 h was measured with a micrometeorological method, the integrated horizontal flux (IHF) method; ammonia-N losses measured with the IHF method and catch cans are not additive. Ammonia-N losses during application with the traveling gun ranged between 3.8% to 9.2% of total ammoniacal nitrogen (TAN) applied, increasing with wind speed and decreasing relative humidity. For two applications, average ammonia loss with the drag-hose was <25% of the traveling gun. Ammonia-N losses from the traveling gun and drag-hose averaged 46.3% (n = 3) and 5.5% (n = 2), respectively, of the TAN applied. Ammonia-N loss during the first 4 h, as percent of total TAN loss was higher with the traveling gun. Whereas traveling gun ammonia losses were affected more by weather (e.g., relative humidity) and crop height, drag-hose losses were impacted more by effluent properties. Wind speed measurement contributed to <6% uncertainty in ammonia loss for both systems during one 4-h period. There are also other sources of uncertainty. Results from this study are comparable with published micrometeorological studies on hog lagoon effluent application. DA - 2009/// PY - 2009/// DO - 10.13031/2013.29236 VL - 25 IS - 6 SP - 963–973 ER - TY - JOUR TI - Modeling ammonia emissions from broiler litter at laboratory scale AU - Liu, Z. AU - Wang, L. AU - Beasley, D. B. AU - Shah, Sanjay T2 - Transactions of the ASABE AB - The objectives of this study were to develop a mechanistic emission model to estimate ammonia flux from broiler litter and to evaluate the model at laboratory scale. In the proposed model, the ammonia flux is essentially a function of the litter's total ammoniacal nitrogen (TAN) content, moisture content, pH, and temperature, as well as the Freundlich partition coefficient (Kf), mass transfer coefficient (KG), ventilation rate (Q), and emission surface area (A). The Freundlich partition coefficient (Kf) was used as a fitting parameter in the model. A dynamic flow-through chamber system and a wind tunnel were designed to measure ammonia fluxes from broiler litter. The dynamic flow-through chamber experiments evaluated the proposed model with various litter samples under a constant temperature and wind profile. The wind tunnel experiments evaluated the proposed model under various temperatures and wind profiles. Model parameters such as Kf and KG were estimated. The results from the two experiments were consistent with each other. The estimated KG ranged from 1.11 to 27.64 m h-1, and the estimated Kf ranged from 0.56 to 4.48 L kg-1. A regression sub-model was developed to estimate Kf as function of litter pH and temperature, which indicated that Kf increased with increasing litter pH and decreased with increasing temperature. The proposed model was used to estimate the equilibrium gas phase ammonia concentration (Cg,0) in litter, and the model-predicted values were compared with the observed values. The normalized mean error (NME), the normalized mean square error (NMSE), and fractional bias (FB) were calculated to be 25%, 12%, and -0.3%, respectively, for all 94 measurements, and the model was able to reproduce 80% of the variability of the data. Sensitivity analysis of the model showed that ammonia flux is very sensitive to litter pH and to a lesser extent temperature. The relative sensitivity of pH or temperature increases as the pH or temperature increases. DA - 2009/// PY - 2009/// DO - 10.13031/2013.29131 VL - 52 IS - 5 SP - 1683–1694 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-70449638099&partnerID=MN8TOARS ER - TY - JOUR TI - DRAINMOD-N II: Evaluated for an agricultural system in Iowa and compared to RZWQM-DSSAT AU - Thorp, K. R. AU - Youssef, M. A. AU - Jaynes, D. B. AU - Malone, R. W. AU - Ma, L. T2 - Transactions of the ASABE AB - A new simulation model for N dynamics, DRAINMOD-N II, has been previously evaluated for only a few sites. We evaluated the model using ten years (1996-2005) of measured data from a subsurface-drained, corn-soybean agricultural system near Story City, Iowa. Nitrogen fertilizer was applied to plots at low, medium, and high rates (57 to 67 kg N ha-1, 114 to 135 kg N ha-1, and 172 to 202 kg N ha-1, respectively) during corn years, and nitrate (NO3) losses from subsurface drains under each plot were monitored biweekly for ten years. Average annual simulated and measured NO3 losses in drainage water were 21.9 and 20.1 kg N ha-1 for the low N rate, 26.6 and 26.5 kg N ha-1 for the medium N rate, and 36.6 and 37.0 kg N ha-1 for the high N rate, respectively. The model efficiency statistics for DRAINMOD-N II simulations of annual subsurface drain NO3 losses were 0.89, 0.95, and 0.94 for the low, medium, and high N rates, respectively. For the same experimental dataset, a comparison of DRAINMOD-N II simulations to that of another model that simulates hydrologic and N dynamics of agricultural systems, the RZWQM-DSSAT hybrid model, demonstrated that the two models were most different in their simulations of soybean N fixation, plant N uptake, and net N mineralization. Future field investigations should focus on generating better understandings of these processes. The results suggest that DRAINMOD-N II can reasonably simulate the effects of different corn-year N rates on losses of NO3 through subsurface drainage lines and that simulations of subsurface drainage NO3 losses by DRAINMOD-N II are comparable to that of RZWQM-DSSAT. DA - 2009/// PY - 2009/// DO - 10.13031/2013.29144 VL - 52 IS - 5 SP - 1557-1573 ER - TY - JOUR TI - The investigation of negative horizontal ventilation for long-term storage of sweetpotatoes AU - Boyette, M. D. T2 - Applied Engineering in Agriculture AB - North Carolina is the largest producer of sweetpotatoes in the United States with an annual production of nearly 320 million kg (NCDACS, 2007). Under optimum storage conditions, sweetpotatoes may be held in marketable condition for longer than 10 months. This allows for orderly marketing throughout the year. In the last 15 years, several hundred long-term storage facilities have been built employing a novel air movement system now termed negative horizontal ventilation (NHV). Most of these facilities are located in North Carolina and other sweetpotato producing areas of the southeastern United States but some have been built in Asia, the Philippines, New Zealand, Canada, and Uruguay. This technology is especially suitable for the large commercial sweetpotato storage facilities now common in the industry. Pack-out percentages (defined as the salable weight removed from storage compared to the salable weight entering) for 8 to 10 month storage utilizing the NHV system average 90%. This compares to 60% to 70% for previous common storage methods and facilities. This article summarizes some of the efforts towards design optimization of these facilities for the curing and storing of sweetpotatoes DA - 2009/// PY - 2009/// DO - 10.13031/2013.28843 VL - 25 IS - 5 SP - 701-708 ER - TY - JOUR TI - Investigation of the 2006 Alexandrium fundyense bloom in the Gulf of Maine: In-situ observations and numerical modeling AU - Li, Yizhen AU - He, Ruoying AU - McGillicuddy, Dennis J., Jr. AU - Anderson, Donald M. AU - Keafer, Bruce A. T2 - CONTINENTAL SHELF RESEARCH AB - In-situ observations and a coupled bio-physical model were used to study the germination, initiation, and development of the Gulf of Maine (GOM) Alexandrium fundyense bloom in 2006. Hydrographic measurements and comparisons with GOM climatology indicate that 2006 was a year with normal coastal water temperature, salinity, current and river runoff conditions. A. fundyense cyst abundance in bottom sediments preceding the 2006 bloom was at a moderate level compared to other recent annual cyst survey data. We used the coupled bio-physical model to hindcast coastal circulation and A. fundyense cell concentrations. Field data including water temperature, salinity, velocity time series and surface A. fundyense cell concentration maps were applied to gauge the model's fidelity. The coupled model is capable of reproducing the hydrodynamics and the temporal and spatial distributions of A. fundyense cell concentration reasonably well. Model hindcast solutions were further used to diagnose physical and biological factors controlling the bloom dynamics. Surface wind fields modulated the bloom's horizontal and vertical distribution. The initial cyst distribution was found to be the dominant factor affecting the severity and the interannual variability of the A. fundyense bloom. Initial cyst abundance for the 2006 bloom was about 50% of that prior to the 2005 bloom. As the result, the time-averaged gulf-wide cell concentration in 2006 was also only about 60% of that in 2005. In addition, weaker alongshore currents and episodic upwelling-favorable winds in 2006 reduced the spatial extent of the bloom as compared with 2005. DA - 2009/9/30/ PY - 2009/9/30/ DO - 10.1016/j.csr.2009.07.012 VL - 29 IS - 17 SP - 2069-2082 SN - 1873-6955 KW - Harmful algal bloom KW - Coastal circulation KW - Gulf of Maine KW - Bio-physical interaction ER - TY - JOUR TI - Indicator Bacteria Removal in Storm-Water Best Management Practices in Charlotte, North Carolina AU - Hathaway, J. M. AU - Hunt, W. F. AU - Jadlocki, S. T2 - JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE AB - Water quality degradation due to pathogen pollution is a major concern in the United States. Storm-water runoff is an important contributor to the transport of indicator bacteria from urbanized watersheds to nearby surface waters. With total maximum daily loads being established to reduce the export of indicator bacteria to surface waters, storm-water best management practices (BMPs) may be an important tool in treating indicator bacteria in runoff. However, the ability of these systems to remove indicator bacteria is not well established. A study in Charlotte, N.C., monitored nine storm-water BMPs (one wet pond, two storm-water wetlands, two dry detention basins, one bioretention area, and three proprietary devices) for fecal coliform and Escherichia coli (E. coli). A wet pond, two wetlands, a bioretention area, and a proprietary device all removed fecal coliform with an efficiency higher than 50%; however, only the wetlands and bioretention area had significantly different influent and effluent concentrations (p<0.05). For E. coli, only one of the wetlands and the bioretention area provided a concentration reduction greater than 50%, both of which had a significant difference in influent and effluent concentrations (p<0.05). Only one of the nine BMPs had a geometric mean effluent concentration of fecal coliform lower than the U.S. EPA target value, while four of the nine BMPs had geometric mean effluent concentrations lower than the U.S. EPA standard for E. coli. This study showed that some BMPs may be useful for treatment of indicator bacteria; however, other BMPs did not perform well. Because wet, nutrient-rich environments exist in many storm-water BMPs, there is a potential for indicator bacteria to persist in these systems. DA - 2009/12// PY - 2009/12// DO - 10.1061/(asce)ee.1943-7870.0000107 VL - 135 IS - 12 SP - 1275-1285 SN - 0733-9372 ER - TY - JOUR TI - Saccharification and Fermentation of Dilute-Acid-Pretreated Freeze-Dried Switchgrass AU - Yang, Ying AU - Sharma-Shivappa, Ratna R. AU - Burns, Joseph C. AU - Cheng, Jay T2 - ENERGY & FUELS AB - This study investigated the potential of three freeze-dried switchgrass germplasms (St6-1, St6-3E, and St6-3F) as whole plants or their stems and leaves for bioethanol production. Whole switchgrass germplasms contained 24.34−30.95% glucan, 14.68−18.58% xylan, and 17.39−19.46% lignin. Switchgrass samples were pretreated with dilute sulfuric acid at concentrations of 0.5, 1.0, or 1.5% (w/v) for 30, 45, or 60 min at 121 °C and 15 psi. Although lignin degradation was limited, over 80% hemicellulose solublization was observed, especially in leaf samples, and the removal could be enhanced by increasing the pretreatment intensity through acid concentration and treatment time adjustment. Within each germplasm, pretreated samples with the least lignin content or greatest percent hemicellulose (xylan and arabinan) solublization were hydrolyzed enzymatically by cellulase at 0, 15, or 30 filter paper units (FPU)/g of dry biomass supplemented with cellobiase. Although the addition of cellulase greatly improved cellulose to glucose conversion, no significant (p ≥ 0.05) differences were observed between activity levels of 15 and 30 FPU/g of dry biomass. Pretreatment significantly (p < 0.05) improved cellulose conversion in samples with the greatest hemicellulose solublization; complete cellulose hydrolysis was observed in some St6-3F samples. Fermentation of hydrolyzates with Saccharomyces cerevisiae (ATCC 24859) resulted in the greatest ethanol yield of 0.083 g of ethanol/g of raw St6-3F switchgrass whole plant, which was 60% of the theoretical yield. Results from this study demonstrated the potential of new switchgrass germplasms as energy crops for bioethanol production through dilute sulfuric acid pretreatment. DA - 2009/11// PY - 2009/11// DO - 10.1021/ef9003335 VL - 23 IS - 11 SP - 5626-5635 SN - 1520-5029 ER - TY - JOUR TI - Seepage erosion in layered stream bank material AU - Lindow, Nick AU - Fox, Garey A. AU - Evans, Robert O. T2 - EARTH SURFACE PROCESSES AND LANDFORMS AB - Abstract Current stream restoration practices often require anthropogenic manipulation of natural field soils to reconstruct stream banks in the absence of stabilizing vegetation. For this study, researchers conducted laboratory experiments on reconstructed, non‐vegetated stream banks with layered soils experiencing seepage. The objective of the study was to determine the effect of seepage, pore water pressure, and bank geometry on erosion and bank stability of layered streambanks. The experimental design consisted of an intermediate‐size soil lysimeter packed with a sandy clay loam top soil and an underlying fine sand layer at three bank slopes (90°, 45° and 26°). Shallow groundwater flow and seepage resulted in bank failure of geometrically stable banks. Pop out failures, liquid deformation, and piping were all observed failure mechanisms in the underlying sand material, dependent on the bank angle. Groundwater seepage processes created small‐scale failures of the underlying sand leading to larger‐scale failures of the overlying sandy clay loam. The underlying sand layer eroded according to the initial bank angle and change in overburden loading. The overlying loam layer failed along linear failure planes. The gradually sloped bank (i.e. 26° slope) failed faster, hypothesized to be due to less confining pressure and greater vertical seepage forces. Researchers analyzed the laboratory experiments using the Bank Stability and Toe Erosion Model, version 4·1. The model calculated an accurate shear surface angle similar to the failure angle observed in the lysimeter tests. The model predicted failure only for the undercut 90° bank slope, and indicated stable conditions for the other geometries. Steeper initial bank slopes and undercut banks decreased the bank factor of safety. The observed failure mechanisms and measured saturation data indicated an interaction between overburden pressure, seepage forces, and bank slope on bank stability. Future bank stability modeling would benefit by incorporating lateral seepage erosion and soil liquefaction prediction calculations. Copyright © 2009 John Wiley & Sons, Ltd. DA - 2009/9/30/ PY - 2009/9/30/ DO - 10.1002/esp.1874 VL - 34 IS - 12 SP - 1693-1701 SN - 1096-9837 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-70349884157&partnerID=MN8TOARS KW - shallow groundwater flow KW - sapping KW - piping KW - stream restoration KW - bank stability ER - TY - JOUR TI - Real-Time Airflow Rate Measurements from Mechanically Ventilated Animal Buildings AU - Hoff, Steven J. AU - Bundy, Dwaine S. AU - Nelson, Minda A. AU - Zelle, Brian C. AU - Jacobson, Larry D. AU - Heber, Albert J. AU - Ni, Jiqin AU - Zhang, Yuanhui AU - Koziel, Jacek A. AU - Beasley, David B. T2 - JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION AB - This paper describes techniques used to determine airflow rate in multiple emission point applications typical of animal housing. An accurate measurement of building airflow rate is critical to accurate emission rate estimates. Animal housing facilities rely almost exclusively on ventilation to control inside climate at desired conditions. This strategy results in building airflow rates that range from about three fresh-air changes per hour in cold weather to more than 100 fresh-air changes per hour in hot weather. Airflow rate measurement techniques used in a comprehensive six-state study could be classified in three general categories: fan indication methods, fan rotational methods, and airspeed measurement methods. Each technique is discussed and implementation plans are noted. A detailed error analysis is included that estimated the uncertainty in airflow rate between +/-5 and +/-6.1% of reading at a building operating static pressure, air temperature, relative humidity, and barometric pressure of 20 Pa, 25 degrees C, 50%, and 97,700 Pa, respectively. DA - 2009/6// PY - 2009/6// DO - 10.3155/1047-3289.59.6.683 VL - 59 IS - 6 SP - 683-694 SN - 1047-3289 ER - TY - JOUR TI - Microbial pretreatment of cotton stalks by submerged cultivation of Phanerochaete chrysosporium AU - Shi, Jian AU - Sharma-Shivappa, Ratna R. AU - Chinn, Mari S. T2 - BIORESOURCE TECHNOLOGY AB - This study used the fungus, Phanerochaete chrysosporium, to pretreat cotton stalks with two methods, shallow stationary and agitated cultivation, at three supplemental salt concentrations. Pretreatment efficiencies were compared by evaluating lignin degradation, solid recovery and carbohydrate availability over a 14-day period. Shallow stationary cultivation with no salts gave 20.7% lignin degradation along with 76.3% solid recovery and 29.0% carbohydrate availability. The highest lignin degradation of 33.9% at a corresponding solid recovery and carbohydrate availability of 67.8% and 18.4%, respectively, was obtained through agitated cultivation with Modified NREL salts. Cultivation beyond 10 days did not significantly increase lignin degradation during 14 days of pretreatment. Manganese addition during shallow stationary and agitated cultivation resulted in higher solid recoveries of over 80% but lower lignin degradation. Although agitated cultivation resulted in better delignification, results indicate that pretreatment under submerged shallow stationary conditions provides a better balance between lignin degradation and carbohydrate availability. DA - 2009/10// PY - 2009/10// DO - 10.1016/j.biortech.2008.10.060 VL - 100 IS - 19 SP - 4388-4395 SN - 1873-2976 KW - Fungal pretreatment KW - Biofuel KW - Phanerochaete chrysosporium KW - Cotton residue KW - Delignification ER - TY - JOUR TI - Grain-boundary interactions and orientation effects on crack behavior in polycrystalline aggregates AU - Shi, J. AU - Zikry, M. A. T2 - INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES AB - A dislocation-density grain–boundary interaction scheme has been developed to account for the interrelated dislocation-density interactions of emission, absorption and transmission in GB regions. The GB scheme is based on slip-system compatibility, local resolved shear stresses, and immobile and mobile dislocation-density accumulation at critical GB locations. To accurately represent dislocation-density evolution, a conservation law for dislocation-densities is used to balance dislocation-density absorption, transmission and emission from the GB. The behavior of f.c.c. polycrystalline copper, with different random low and high angle GBs, are investigated for different crack lengths. For aggregates with random low angle GBs, dislocation-density transmission dominates at the GBs, which can indicate that the low angle GB will not significantly change crack growth directions. For aggregates with random high angle GBs, extensive dislocation-density absorption and pile-ups occur. The high stresses associated with this behavior, along the GBs, can result in intergranular crack growth due to potential crack nucleation sites in the GB. DA - 2009/10/15/ PY - 2009/10/15/ DO - 10.1016/j.ijsolstr.2009.07.019 VL - 46 IS - 21 SP - 3914-3925 SN - 1879-2146 KW - Grain boundaries KW - Dislocation-density grain-boundary interaction KW - Finite elements KW - Crystal plasticity KW - Intergranular crack KW - Transgranular crack ER - TY - JOUR TI - Sampling and analytical variability associated with the determination of aflatoxins and ochratoxin A in bulk lots of powdered ginger marketed in 1-lb bags AU - Whitaker, Thomas B. AU - Trucksess, Mary W. AU - Weaver, Carol M. AU - Slate, Andrew T2 - ANALYTICAL AND BIOANALYTICAL CHEMISTRY DA - 2009/11// PY - 2009/11// DO - 10.1007/s00216-009-2880-z VL - 395 IS - 5 SP - 1291-1299 SN - 1618-2650 KW - Aflatoxin KW - Ochratoxin A KW - Ginger KW - Sampling and analytical variability KW - Sampling KW - Foods/beverages KW - Quality assurance/control ER - TY - JOUR TI - Leaching of Nutrients and Trace Elements from Stockpiled Turkey Litter into Soil AU - Shah, Sanjay B. AU - Hutchison, Kimberly J. AU - Hesterberg, Dean L. AU - Grabow, Garry L. AU - Huffman, Rodney L. AU - Hardy, David H. AU - Parsons, James T. T2 - JOURNAL OF ENVIRONMENTAL QUALITY AB - In addition to nutrients, poultry are fed trace elements (e.g., As) for therapeutic purposes. Although a large proportion of the nutrients are assimilated by the birds, nearly all of the As is excreted. Hence, turkey litter constituents can leach into the soil and contaminate shallow ground water when it is stockpiled uncovered on bare soil. This study quantified the leaching of turkey litter constituents from uncovered stockpiles into the underlying soil. Four stockpiles were placed on Orangeburg loamy sand in summer 2004 for 162 d; 14 d after their removal, four stockpiles were created over the same footprints and left over winter for 162 d. Soil samples at depths of 7.6 to 30.5 cm and 30.5 to 61 cm adjacent to and beneath the stockpiles were compared for pH, electrical conductivity, total C, dissolved organic C, N species, P, water-extractable (WE)-P, As, WE-As, Cu, Mn, and Zn. All WE constituents affected the 7.6- to 30.5-cm layer, and some leached deeper; for example, NH(4)(+)-N concentrations were 184 and 62 times higher in the shallow and deep layers, respectively. During winter stockpiling, WE-As concentrations beneath the stockpiles tripled and doubled in the 7.6- to 30.5-cm and 30.5- to 61-cm layers, respectively, with WE-As being primarily as As(V). Heavy dissolved organic C and WE-P leaching likely increased solubilization of soil As, although WE-As concentrations were low due to the Al-rich soil and low-As litter. When used as drinking water, shallow ground water should be monitored on farms with a history of litter stockpiling on bare soil; high litter As; and high soil As, Fe, and Mn concentrations. DA - 2009/// PY - 2009/// DO - 10.2134/jeq2007.0639 VL - 38 IS - 3 SP - 1053-1065 SN - 1537-2537 ER - TY - JOUR TI - Landscape irrigation by evapotranspiration-based irrigation controllers under dry conditions in Southwest Florida AU - Davis, S. L. AU - Dukes, M. D. AU - Miller, G. L. T2 - AGRICULTURAL WATER MANAGEMENT AB - Due to high demand for aesthetically pleasing urban landscapes from continually increasing population in Florida, new methods must be explored for outdoor water conservation. Three brands of evapotranspiration (ET) controllers were selected based on positive water savings results in arid climates. ET controllers were evaluated on irrigation application compared to a time clock schedule intended to mimic homeowner irrigation schedules. Three ET controllers were tested: Toro Intelli-sense; ETwater Smart Controller 100; Weathermatic SL1600. Other time-based treatments were TIME, based on the historical net irrigation requirement and RTIME that was 60% of TIME. Each treatment was replicated four times for a total of twenty St. Augustinegrass plots which were irrigated through individual irrigation systems. Treatments were compared to each other and to a time-based schedule without rain sensor (TIME WORS) derived from TIME. The study period, August 2006 through November 2007, was dry compared to 30-year historical average rainfall. The ET controllers averaged 43% water savings compared to a time-based treatment without a rain sensor and were about twice as effective and reducing irrigation compared to a rain sensor alone. There were no differences in turfgrass quality across all treatments over the 15-month study. The controllers adjusted their irrigation schedules to the climatic demand effectively, with maximum savings of 60% during the winter 2006–2007 period and minimum savings of 9% during spring 2007 due to persistent dry conditions. RTIME had similar savings to the ET controllers compared to TIME WORS indicating that proper adjustment of time clocks could result in substantial irrigation savings. However, the ET controllers would offer consistent savings once programmed properly. DA - 2009/12// PY - 2009/12// DO - 10.1016/j.agwat.2009.08.005 VL - 96 IS - 12 SP - 1828-1836 SN - 1873-2283 KW - Drought KW - Turfgrass KW - Water conservation ER - TY - JOUR TI - Field evaluation of a proprietary storm-water treatment system: Removal efficiency and relationships to peak flow, season, and dry time AU - Cates, E. L. AU - Westphal, M. J. AU - Cox, J. H. AU - Calabria, J. AU - Patch, S. C. T2 - Journal of Environmental Engineering (New York, N.Y.) DA - 2009/// PY - 2009/// VL - 135 IS - 7 SP - 511-517 ER - TY - JOUR TI - Could ozonation technology really work for mitigating air emissions from animal feeding operations? AU - Li, Q. AU - Wang, L. AU - Liu, Z. AU - Kamens, R.M. T2 - Journal of the Air and Waste Management Association AB - Abstract Among various mitigation technologies for ammonia (NH3) emission control at animal feeding operations (AFOs), room ozonation technology is the most controversial. This paper aims to present full perspectives of ozonation techniques through a literature review and a series of laboratory experiments. In the literature review, ozone chemistry was summarized to address (1) ozone and NH3 reactions, (2) ozone and odor reactions, (3) ozone and particulate matter reactions, and (4) ozone and microorganism reactions. A series of laboratory experiments were conducted in a dual large outdoor aerosol smog chamber (270 m3). NH3 and fine particle number concentrations from ozone-treated and control experiments were compared. The experimental results indicated that (1) ozone has no significant effect on NH3 emissions concentrations or NH3 decay of an outdoor chamber; and (2) with ozone treatment, high concentration of particles in the “high-risk” respiratory fraction (in submicron range) are generated. DA - 2009/// PY - 2009/// DO - 10.3155/1047-3289.59.10.1239 VL - 59 IS - 10 SP - 1239-1246 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-70449729852&partnerID=MN8TOARS ER - TY - JOUR TI - Compressed ion temperature gradient turbulence in diverted tokamak edge AU - Chang, C. S. AU - Ku, S. AU - Diamond, P. H. AU - Lin, Z. AU - Parker, S. AU - Hahm, T. S. AU - Samatova, N. T2 - PHYSICS OF PLASMAS AB - It is found from a heat-flux-driven full-f gyrokinetic particle simulation that there is ion temperature gradient (ITG) turbulence across an entire L-mode-like edge density pedestal in a diverted tokamak plasma in which the ion temperature gradient is mild without a pedestal structure, hence the normalized ion temperature gradient parameter ηi=(d log Ti/dr)/(d log n/dr) varies strongly from high (&gt;4 at density pedestal top/shoulder) to low (&lt;2 in the density slope) values. Variation of density and ηi is in the same scale as the turbulence correlation length, compressing the turbulence in the density slope region. The resulting ion thermal flux is on the order of experimentally inferred values. The present study strongly suggests that a localized estimate of the ITG-driven χi will not be valid due to the nonlocal dynamics of the compressed turbulence in an L-mode-type density slope. While the thermal transport and the temperature profile saturate quickly, the E×B rotation shows a longer time damping during the turbulence. In addition, a radially in-out mean potential variation is observed. DA - 2009/5// PY - 2009/5// DO - 10.1063/1.3099329 VL - 16 IS - 5 SP - SN - 1089-7674 KW - plasma boundary layers KW - plasma density KW - plasma instability KW - plasma simulation KW - plasma toroidal confinement KW - plasma transport processes KW - plasma turbulence KW - Tokamak devices ER - TY - JOUR TI - A Risk Assessment Model for Importation of United States Milling Wheat Containing Tilletia contraversa AU - Peterson, G. L. AU - Whitaker, T. B. AU - Stefanski, R. J. AU - Podleckis, E. V. AU - Phillips, J. G. AU - Wu, J. S. AU - Martinez, W. H. T2 - PLANT DISEASE AB - Dwarf bunt of wheat, caused by the fungus Tilletia contraversa, is a pathogen historically limited in distribution by its very specific climatic requirements for establishment. In an effort to both address the need for adequate protection and eliminate unwarranted trade barriers, a number of countries have examined restrictions on importing milling wheat containing teliospores of T. contraversa. Pest risk analysis (PRA), under the guidelines of the World Trade Organization and Food and Agriculture Organization, has become an internationally accepted process for evaluating such issues. As a component of a dwarf bunt PRA, our objective was to develop a quantitative mathematical model to evaluate and communicate the potential risk of dwarf bunt establishment from the importation of U.S. milling wheat containing teliospores of T. contraversa. A T. contraversa–risk model (TCK-risk model) was developed using new data, historic literature, and industry statistics to estimate teliospore diversion from transport and milling processes, spore contamination levels, grain handling, and end-product usage. A climatic model was developed to identify potential regions where the environment was favorable for disease development. The likelihood of disease establishment and wheat yield loss was determined using the model to conduct Monte Carlo simulations of 100,000 wheat shipping-years. The model is dynamic in that individual components can be easily updated or modified in order to determine the effect of numerous scenarios (e.g., climate changes, shipping tonnage, contamination levels, mitigation strategies) on the probability of dwarf bunt establishment. TCK-risk model evaluation scenarios previously conducted for the People's Republic of China, Brazil, Mexico, and Peru are presented as examples. DA - 2009/6// PY - 2009/6// DO - 10.1094/PDIS-93-6-0560 VL - 93 IS - 6 SP - 560-573 SN - 0191-2917 ER - TY - JOUR TI - Thermal modeling of greenhouse aquaculture raceway systems AU - Li, Shuhai AU - Willits, Daniel H. AU - Browdy, Craig L. AU - Timmons, Michael B. AU - Losordo, Thomas M. T2 - AQUACULTURAL ENGINEERING AB - A mechanistic model was developed to describe the thermal behavior of an indoor raceway system with an inflated double polyethylene cover. The model describes the heat balances of the two covers, the inside air, the water in the raceway and the soil beneath the raceway. On-site measurements were made with an experimental system at the Waddell Mariculture Center in South Carolina. The collected data were used to calibrate the model. Comparison of the predictions with observations showed that the average absolute errors of air temperature and water temperature were 1.4 and 0.5 °C, respectively and was 8% for the relative humidity. The accuracies are regarded as sufficient for the model to be useful for more general application. Model simulations were used to investigate the effects of the greenhouse on the air and water temperatures, to examine the heat fluxes and to calculate the heat consumption and costs at four different climatic locations. The results suggest that under the mild weather conditions in January near Charleston, SC where the daily mean temperature is 7.6 °C and solar radiation is 121 W m−2, the inside air temperature increases by 5.6 °C and water temperature increases by 9.7 °C on average for the system with the 0.85 m deep raceway covering 70% of the greenhouse floor. An examination of the heat fluxes suggests that thermal radiation is a major mechanism of heat loss for the greenhouse covers and the water surface. Convection from the water surface is also a significant mechanism for latent and sensible heat loss from the raceway. Reducing these heat flows will help conserve and utilize energy. The yearly heating requirements to keep the water temperature at 28 °C for the experimental system were estimated to be 870, 520, 274 and 221 kWh per square meter of raceway for Syracuse, NY, Roanoke, VA, Charleston, SC and Baton Rouge, LA, respectively. The model was deemed to be a useful tool for exploring the performance of greenhouse raceway systems under different scenarios, such as different cover materials, sizes and climates. DA - 2009/7// PY - 2009/7// DO - 10.1016/j.aquaeng.2009.04.002 VL - 41 IS - 1 SP - 1-13 SN - 1873-5614 KW - Modeling KW - Greenhouse KW - Aquaculture KW - Raceway KW - Heating ER - TY - JOUR TI - Room-temperature oxidation of propanal using catalysts synthesized by electrochemical deposition AU - Kolar, P. AU - Kastner, J. R. T2 - Transactions of the ASABE AB - Poultry rendering emissions contain aldehydes that are reactive and regulated volatile organic compounds requiring mitigation. This research presents an application of catalytic oxidation technology to treat aldehydes at room temperature using ozone as an oxidant and metal oxides deposited on activated carbon as catalysts. Four types of catalysts were tested: activated carbon, activated carbon impregnated with iron oxide, and activated carbon electrochemically deposited with nickel and cobalt oxides. Iron oxides were deposited on activated carbon via traditional dry impregnation, while nickel and cobalt were deposited on activated carbon via electrochemical deposition. The prepared catalysts' activities were tested in a continuous differential packed-bed reactor, using an ozone generator and gas chromatography. Propanal (50 to 250 ppmv) was tested as a representative contaminant, and ozone (1500 ppmv) was used as an oxidant. Experiments with activated carbon as a catalyst indicated that 70% removal was achieved within 0.1 s residence time, and the oxidation rates of propanal were determined to be in the range of 90 10-9 to 300 10-9 mol/g-s. However, when iron oxide-deposited activated carbon was tested for propanal oxidation, the oxidation rates decreased significantly (7 10-9 to 60 10-9 mol/g-s), probably due to the clogging of the micro- and meso-pores of the activated carbon support with iron oxide particles. When the electrochemically deposited nickel and cobalt oxide catalysts were tested, propanal oxidation rates increased by 20% to 25%. Based on the preliminary results, electrochemical deposition on activated carbon appears to be a valuable tool in synthesizing advanced catalysts for use in air pollution remediation. DA - 2009/// PY - 2009/// DO - 10.13031/2013.27783 VL - 52 IS - 4 SP - 1337-1344 ER - TY - JOUR TI - Field Study of the Ability of Two Grassed Bioretention Cells to Reduce Storm-Water Runoff Pollution AU - Passeport, Elodie AU - Hunt, William F. AU - Line, Daniel E. AU - Smith, Ryan A. AU - Brown, Robert A. T2 - JOURNAL OF IRRIGATION AND DRAINAGE ENGINEERING AB - Two grassed bioretention cells including internal storage zones (ISZs) were monitored for 16months in central North Carolina. Each cell had a surface area of 106m2 and fill media depths were 0.75 and 1.05m for the north (North) and the south (South) cells, respectively. Asphalt parking lot inflow and outflows were analyzed for nitrogen and phosphorus forms and fecal coliform (FC). Outflow volumes and peak flows for individual storms were generally less than those of inflow. Overall, except for NO2,3–N , effluent nitrogen species event mean concentrations (EMCs) and loads were significantly (α=0.05) lower than those of the inflow, and nitrogen species load reductions ranged from 47 to 88%. Apart from fall and winter, during which a longer hydraulic contact time seemed to be needed, the ISZs appeared to improve denitrification. Total phosphorus (TP) and OPO4-P EMCs were significantly lower than those of the inlet. Reductions were 58% (South) and 63% (North) for TP and 78% (North) and 74% (South) for OPO4–P . There was no significant difference in TP and OPO4–P loads between the inlet and the two outlets. Moreover, effluent concentrations for both phosphorus species were low, relative to other studies. The best nutrient EMC and load reductions occurred during the warm and humid seasons. When considering effluent concentrations in addition to removal rates, the grassed cells showed promising results for FC and nutrient pollution abatement when compared to conventionally vegetated bioretention (trees, shrubs, and mulch) previously studied in North Carolina. DA - 2009/// PY - 2009/// DO - 10.1061/(ASCE)IR.1943-4774.0000006 VL - 135 IS - 4 SP - 505-510 SN - 1943-4774 ER - TY - JOUR TI - Bioretention Impact on Runoff Temperature in Trout Sensitive Waters AU - Jones, Matthew P. AU - Hunt, William F. T2 - JOURNAL OF ENVIRONMENTAL ENGINEERING AB - A study was conducted in western North Carolina, along the southeastern extent of the U.S. trout populations, to examine the effect of bioretention areas on runoff temperature. Four bioretention areas were monitored during the summers of 2006 and 2007. It was found that smaller bioretention areas, with respect to the size of their contributing watershed, were able to significantly reduce both maximum and median water temperatures between the inlet and outlet. The proportionately larger bioretention areas were only able to significantly reduce maximum water temperatures between the inlet and outlet; however, these systems showed evidence of substantial reductions in outflow quantity, effectively reducing the thermal impact. Despite temperature reductions, effluent temperatures still posed a potential threat to coldwater streams during the peak summer months. During the summer months, effluent temperatures were generally coolest at the greatest soil depths, supporting evidence of an optimum drain depth between 90 and 120 cm. The ability of bioretention areas to reduce storm-water temperature and flows supports their application to reduce the thermal impacts of urban storm-water runoff. DA - 2009/8// PY - 2009/8// DO - 10.1061/(asce)ee.1943-7870.0000022 VL - 135 IS - 8 SP - 577-585 SN - 1943-7870 ER - TY - JOUR TI - Biomechanical Comparison of Four Soft Tissue Replacement Materials: An In Vitro Evaluation of Single and Multilaminate Porcine Small Intestinal Submucosa, Canine Fascia Lata, and Polypropylene Mesh AU - Arnold, Gregory A. AU - Mathews, Kyle G. AU - Roe, Simon AU - Mente, Peter AU - Seaboch, Tim T2 - VETERINARY SURGERY AB - Objective— To compare mechanical performance of 4 soft tissue replacement materials. Study Design— Experimental. Sample Population— Polypropylene mesh (PM), single‐layer porcine small intestinal submucosa (SIS), multilaminate (4‐layer) porcine small intestinal submucosa (MLSIS), and canine fascia lata (FL). Methods— The mechanical properties of each material were determined by testing to failure on a materials testing machine. Samples of each material (n=10) were tested in 3 different modes: resistance to suture pullout, tensile testing, and push‐through testing. PM was tested both parallel (PMa) to and perpendicular (PMb) to its longitudinal cord orientation. SIS and FL were similarly tested in 2 orthogonal directions. Results— With some exceptions, the following generalizations can be made regarding the mechanical performance of the materials tested: Suture pullout— FL>PMa=PMb>MLSIS>SIS ( P ≤.04). Tensile testing —FL>PMa>PMb>MLSIS>SIS ( P ≤.02). Push‐through testing— FL>PM>MLSIS>SIS ( P ≤.003). Conclusions— PM accommodated a significantly higher load and energy to yield when its longitudinal cords were oriented parallel with the tension axis (PMa). FL performed similarly to the PM, with the exception of limited elongation in tension. MLSIS had biomechanical characteristics that were inferior to FL and PM but superior to SIS. Clinical Relevance— PM's orientation may need to be considered when used clinically. FL is a biomechanically suitable soft tissue replacement material but its use may be limited by currently available sizes. SIS cannot be recommended in high‐strain environments. DA - 2009/10// PY - 2009/10// DO - 10.1111/j.1532-950X.2009.00577.x VL - 38 IS - 7 SP - 834-844 SN - 1532-950X ER - TY - JOUR TI - Autohydrolysis pretreatment of Coastal Bermuda grass for increased enzyme hydrolysis AU - Lee, Jung Myoung AU - Shi, Jian AU - Venditti, Richard A. AU - Jameel, Hasan T2 - BIORESOURCE TECHNOLOGY AB - Coastal Bermuda grass (GBG) was pretreated using an autohydrolysis process with different temperatures and times, and the pretreated materials were enzymatically hydrolyzed using a mixture of cellulase, xylanase and β-glucosidase with different enzyme loadings to evaluate sugar yields. Compared with untreated CBG, autohydrolysis pretreatments at all elevated temperatures and residence times tested enhanced enzymatic digestibility of both cellulose and hemicellulose. Increasing the temperature and residence time also helps to solubilize hemicelluloses, with 83.3% of the hemicelluloses solubilized at 170 °C for 60 min treatment. However, higher temperatures and longer times resulted in an overall lower sugar recovery when considering monosaccharides in the prehydrolyzate combined with the enzyme hydrolyzate. Autohydrolysis at 150 °C for 60 min provided the highest overall sugar yield for the entire process. A total of 43.3 g of sugars, 70% of the theoretical sugar yield, can be generated from 100 g CBG, 15.0 g of monosaccharide in the prehydrolyzate and 28.3 g in the enzyme hydrolyzate. The conversion efficiency could be further improved by optimizing enzyme dosages and xylanases:cellulases ratio and pretreatment conditions to minimize sugar degradation. DA - 2009/12// PY - 2009/12// DO - 10.1016/j.biortech.2008.12.068 VL - 100 IS - 24 SP - 6434-6441 SN - 1873-2976 KW - Autohydrolysis KW - Coastal Bermuda grass KW - Enzymatic hydrolysis KW - Sugar analysis ER - TY - JOUR TI - A technique for assessing environmental impact risks of agricultural systems AU - Sydorovych, Olha AU - Raczkowski, Charles W. AU - Wossink, Ada AU - Mueller, J. Paul AU - Creamer, Nancy G. AU - Hu, Shuijin AU - Bell, Melissa AU - Tu, Cong T2 - RENEWABLE AGRICULTURE AND FOOD SYSTEMS AB - Abstract Conventional agriculture often aims to achieve high returns without allowing for sustainable natural resource management. To prevent environmental degradation, agricultural systems must be assessed and environmental standards need to be developed. This study used a multi-factor approach to assess the potential environmental impact risk of six diverse systems: five production systems and a successional system or abandoned agronomic field. Assessment factors were soil quality status, amount of pesticide and fertilizer applied and tillage intensity. The assessment identified the best management practices (BMP)–conventional tillage system as a high-risk system mostly because of extensive tillage. The certified organic system was also extensively tilled and was characterized by P build-up in the soil, but performed well based on other assessment factors. Conversely, the BMP–no tillage and the crop–animal integrated system were characterized as low risk mainly because of reduced tillage. The paper discusses assessment strengths and weaknesses, ways to improve indicators used, and the need for additional indicators. We concluded that with further development the technique will become a resourceful tool to promote agricultural sustainability and environmental stewardship and assist policy-making processes. DA - 2009/9// PY - 2009/9// DO - 10.1017/S174217050999010X VL - 24 IS - 3 SP - 234-243 SN - 1742-1713 KW - environmental impact assessment KW - environmental risk indicators KW - agricultural production systems KW - soil quality KW - large-scale systems experiment KW - best management practices KW - farming systems ER - TY - JOUR TI - Expression and Activity of COX-1 and 2 and 5-LOX in Joint Tissues from Dogs with Naturally Occurring Coxofemoral Joint Osteoarthritis AU - Lascelles, B. Duncan X. AU - King, Stephanie AU - Roe, Simon AU - Marcellin-Little, Denis J. AU - Jones, Samuel T2 - JOURNAL OF ORTHOPAEDIC RESEARCH AB - Abstract Understanding the neurobiology of pain in naturally occurring models of osteoarthritis (OA) may improve the understanding of human OA pain. Both COX and LOX have been associated with joint pain. This study evaluated COX‐1, COX‐2, and 5‐LOX expression and activity in a naturally occurring canine model of secondary OA. Hip joint capsule with synovial tissue (HJC) and femoral head subchondral bone (FH) was collected from normal dogs and dogs undergoing total hip replacement for coxofemoral joint OA. Tissues were analyzed for COX‐1, COX‐2, and LOX protein, and PGE 2 and LTB 4 . Significantly more COX‐2 protein was present in OA HJC than normal joints ( p = 0.0009). There was no significant difference in COX‐1 or LOX protein, although LOX protein was increased ( p = 0.069). PGE 2 concentration in normal and OA HJC was similar ( p = 1.0). LTB 4 concentration in OA HJC was significantly greater than normal HJC ( p = 0.028). Significantly more COX‐1 ( p = 0.0098), COX‐2 ( p = 0.0028), and LOX ( p = 0.0095) protein was present in OA FH tissue compared to normal FH tissue. There were no differences in PGE 2 or LTB 4 concentration in normal and OA FH tissue ( p = 0.77 and p = 0.11). Together, these data suggest both COX‐2 and 5‐LOX are appropriate targets for the management of pain associated with naturally occurring OA. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res DA - 2009/9// PY - 2009/9// DO - 10.1002/jor.20864 VL - 27 IS - 9 SP - 1204-1208 SN - 0736-0266 KW - canine KW - osteoarthritis KW - cyclooxygenase KW - lipoxygenase KW - eicosanoids ER - TY - JOUR TI - Dilute Acid Pretreatment of Oven-dried Switchgrass Germplasms for Bioethanol Production AU - Yang, Ying AU - Sharma-Shivappa, Ratna AU - Burns, Joseph C. AU - Cheng, Jay J. T2 - ENERGY & FUELS AB - Bioethanol production potential of three oven-dried switchgrass germplasms (St6−1, St6−3E, and St6−3F) containing 26.65−29.28% glucan, 17.92−19.37% xylan, and 17.74−19.23% lignin (dry matter basis) was investigated. Evaluation of the effect of three acid concentrations (0.5, 1.0, and 1.5% w/v) and residence times (30, 45, and 60 min) on composition of all germplasms indicated significant hemicellulose solublization relying greatly on pretreatment intensity. No apparent delignification was observed during pretreatment. Pretreated samples with the least lignin content or greatest hemicellulose solubilization within each germplasm were selected for hydrolysis and fermentation. Enzymatic hydrolysis at cellulase activities of 0, 15, and 30 FPU (filter paper units)/g dry biomass indicated that addition of cellulase significantly improved glucan hydrolysis (P < 0.05) but supplementation with xylanase did not statistically improve hydrolysis (P > 0.05). Glucan-to-glucose conversion was enhanced by acid pretreatments, especially those resulting in greater hemicellulose solubilization. The greatest glucan conversion of 91.8% was obtained from 60 min/1.5% acid pretreated St6−3E switchgrass hydrolyzed at 30 FPU cellulase/g dry biomass supplemented with xylanase. Fermentation of hydrolyzates by Saccharomyces cerevisiae (ATCC 24859) resulted in nearly complete utilization of glucose. The highest ethanol yield of 0.082 g ethanol/g raw St6−3E switchgrass corresponded with 53.5% of theoretical yield based on glucose fermentation. These results demonstrate that the new switchgrass germplasms are potential energy crops for bioethanol production through appropriate processing. DA - 2009/7// PY - 2009/7// DO - 10.1021/ef900043z VL - 23 IS - 7 SP - 3759-3766 SN - 1520-5029 ER - TY - JOUR TI - Chemical and isotopic signature of old groundwater and magmatic solutes in a Costa Rican rain forest: Evidence from carbon, helium, and chlorine AU - Genereux, David P. AU - Webb, Mathew AU - Solomon, D. Kip T2 - WATER RESOURCES RESEARCH AB - C, He, and Cl concentrations and isotopes in groundwater and surface water in a lowland Costa Rican rain forest are consistent with the mixing of two distinct groundwaters: (1) high‐solute bedrock groundwater representing interbasin groundwater flow (IGF) into the rain forest and (2) low‐solute local groundwater recharged in the lowlands. In bedrock groundwater, high δ 13 C (−4.89‰), low 14 C (7.98 pM), high R/R A for He (6.88), and low 36 Cl/Cl (17 × 10 −15 ) suggest that elevated tracer concentrations are derived from magmatic outgassing and/or weathering of volcanic rock beneath nearby Volcan Barva. In local groundwater, the magmatic signature is absent, and data suggest atmospheric sources for He and Cl and a biogenic soil gas CO 2 source for dissolved inorganic carbon. Dating of 14 C suggests that the age of bedrock groundwater is 2400–4000 years (most likely at the lower end of the range). Local groundwater has 14 C > 100 pM, indicating the presence of “bomb carbon” and thus ages less than ∼55 years. Overall, data are consistent with a conceptual hydrologic model originally proposed on the basis of water budget and major ion data: (1) large variation in solute concentrations can be explained by mixing of the two distinct groundwaters, (2) bedrock groundwater is much older than local groundwater, (3) elevated solute concentrations in bedrock groundwater are derived from volcanic fluids and/or rock, and (4) local groundwater has not interacted with volcanic rock. Tracers with different capabilities converge on the same hydrologic interpretation. Also, transport of magmatic CO 2 into the lowland rain forest via IGF seems to be significant relative to other large ecosystem‐level carbon fluxes. DA - 2009/8/11/ PY - 2009/8/11/ DO - 10.1029/2008wr007630 VL - 45 SP - SN - 1944-7973 ER - TY - JOUR TI - Influence of process parameters on growth of Clostridium ljungdahlii and Clostridium autoethanogenum on synthesis gas AU - Cotter, Jacqueline L. AU - Chinn, Mari S. AU - Grunden, Amy M. T2 - ENZYME AND MICROBIAL TECHNOLOGY AB - Effects of initial medium pH and gas flow rate on Clostridium ljungdahlii and Clostridium autoethanogenum in liquid batch, continuous gas fermentations were investigated. Synthesis gas components were supplied at varying flow rates (5, 7.5 and 10 mL/min) for C. ljungdahlii (pH 6.8 and 5.5) and C. autoethanogenum (pH 6.0). Growth on synthesis gas was slower than growth on sugars. For C. ljungdahlii, higher cell densities were achieved at pH 6.8 (579 mg/L) compared to pH 5.5 (378 mg/L). The ethanol concentration at pH 6.8 was also 110% greater than that at pH 5.5. The interaction of flow rate and pH was statistically significant with the greatest acetate production in the 10 mL/min, pH 6.8 treatment. The ethanol to acetate ratios were smaller at lower pH levels and higher flow rates. In C. autoethanogenum fermentations, higher flow rates resulted in greater end product formation with no significant effect on product ratios. DA - 2009/5/6/ PY - 2009/5/6/ DO - 10.1016/j.enzmictec.2008.11.002 VL - 44 IS - 5 SP - 281-288 SN - 1879-0909 KW - Clostridium ljungdahlii KW - Clostridium autoethanaogenum KW - Synthesis gas fermentation KW - Ethanol KW - Acetate ER - TY - JOUR TI - Grain size, grain boundary sliding, and grain boundary interaction effects on nanocrystalline behavior AU - Shi, J. AU - Zikry, M. A. T2 - MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING AB - A dislocation–density grain boundary (GB) interaction scheme, a GB misorientation dependent dislocation–density relation, and a grain boundary sliding (GBS) model are presented to account for the behavior of nanocrystalline aggregates with grain sizes ranging from 25 nm to 200 nm. These schemes are coupled to a dislocation–density multiple slip crystalline plasticity formulation and specialized finite element algorithms to predict the response of nanocrystalline aggregates. These schemes are based on slip system compatibility, local resolved shear stresses, and immobile and mobile dislocation–density evolution. A conservation law for dislocation–densities is used to balance dislocation–density absorption, transmission and emission from the GB. The relation between yield stresses and grain sizes is consistent with the Hall–Petch relation. The results also indicate that GB sliding and grain-size effects affect crack behavior by local dislocation–density and slip evolution at critical GBs. Furthermore, the predictions indicate that GBS increases with decreasing grain sizes, and results in lower normal stresses in critical locations. Hence, GBS may offset strength increases associated with decreases in grain size. DA - 2009/9/15/ PY - 2009/9/15/ DO - 10.1016/j.msea.2009.05.012 VL - 520 IS - 1-2 SP - 121-133 SN - 1873-4936 KW - Grain boundaries KW - Dislocation-density grain boundary interactions KW - Finite elements KW - Crystal plasticity KW - Hall-Petch relation KW - Grain boundary sliding ER - TY - JOUR TI - Elevated Atmospheric Carbon Dioxide and O-3 Differentially Alter Nitrogen Acquisition in Peanut AU - Tu, Cong AU - Booker, Fitzgerald L. AU - Burkey, Kent O. AU - Hu, Shuijin T2 - CROP SCIENCE AB - ABSTRACT Elevated atmospheric CO 2 and ozone (O 3 ) may affect productivity of legumes in part by altering symbiotic N 2 fixation. To investigate this possibility, measurements of plant biomass, N levels and natural 15 N abundance (δ 15 N) were used to examine the effects of elevated CO 2 and O 3 on N acquisition in field‐grown peanut ( Arachis hypogaea L.) using open‐top chambers. Seasonal 12‐h daily average CO 2 treatment concentrations were 376, 550, and 730 μmol mol −1 Carbon dioxide treatments were applied in reciprocal combinations with seasonal 12‐h daily average O 3 concentrations of 21, 49, and 79 nmol mol −1 At mid‐vegetative growth, elevated CO 2 significantly reduced leaf N concentrations by up to 44%, but not δ 15 N values. Elevated O 3 did not significantly affect N concentrations or δ 15 N values. At harvest, plant N concentrations were similar among treatments except for a 14% reduction in the highest‐level CO 2 –O 3 treatment. Plant N accumulation varied in proportion with treatment effects on biomass production, which was increased with elevated CO 2 when averaged over the O 3 treatments and suppressed by high‐level O 3 at ambient CO 2 Elevated CO 2 reduced plant δ 15 N values in low‐ and mid‐level O 3 treatments while mid‐ and high‐level O 3 increased them at ambient CO 2 The changes in δ 15 N values suggested that N 2 fixation activity was stimulated with elevated CO 2 and inhibited by elevated O 3 Elevated CO 2 ameliorated detrimental O 3 effects to varying extents depending on the concentrations of the two gases. These results indicated that interactions between CO 2 and O 3 on plant physiology can alter N acquisition processes, with impacts on peanut productivity likely dependent in part on these changes. DA - 2009/// PY - 2009/// DO - 10.2135/cropsci2008.10.0603 VL - 49 IS - 5 SP - 1827-1836 SN - 1435-0653 ER - TY - JOUR TI - Simulated effect of drainage water management operational strategy on hydrology and crop yield for Drummer soil in the Midwestern United States AU - Ale, S. AU - Bowling, L. C. AU - Brouder, S. M. AU - Frankenberger, J. R. AU - Youssef, M. A. T2 - AGRICULTURAL WATER MANAGEMENT AB - The hypothetical effects of drainage water management operational strategy on hydrology and crop yield at the Purdue University Water Quality Field Station (WQFS) were simulated using DRAINMOD, a field-scale hydrologic model. The WQFS has forty-eight cropping system treatment plots with 10 m drain spacing. Drain flow observations from a subset of the treatment plots with continuous corn (Zea mays L.) were used to calibrate the model, which was then used to develop an operational strategy for drainage water management. The chosen dates of raising and lowering the outlet during the crop period were 10 and 85 days after planting, respectively, with a control height of 50 cm above the drain (40 cm from the surface). The potential effects of this operational strategy on hydrology and corn yield were simulated over a period of 15 years from 1991 to 2005. On average, the predicted annual drain flows were reduced by 60% (statistically significant at 95% level). This is the most significant benefit of drainage water management since it may reduce the nitrate load to the receiving streams. About 68% of the reduced drain flow contributed to an increase in seepage. Drainage water management increased the average surface runoff by about 85% and slightly decreased the relative yield of corn crop by 0.5% (both are not statistically significant at 95% level). On average, the relative yield due to wet stress (RYw) decreased by 1.3% while relative yield due to dry stress (RYd) increased by 1%. Overall, the relative crop yield increased in 5 years (within a range of 0.8–6.9%), decreased in 8 years (within a range of 0.2–5.5%), and was not affected in the remaining 2 years. With simulated drainage water management, the water table rose above the conventional drainage level during both the winter and the crop periods in all years (except 2002 crop season). The annual maximum winter period rise ranged between 47 cm (1995) and 87 cm (1992), and the annual maximum crop period rise ranged between no effect (2002) and 47 cm (1993). DA - 2009/4// PY - 2009/4// DO - 10.1016/j.agwat.2008.10.005 VL - 96 IS - 4 SP - 653-665 SN - 1873-2283 KW - Controlled drainage KW - DRAINMOD KW - DRAINMOD-NII KW - Hydrologic modeling KW - Subsurface drainage ER - TY - JOUR TI - Effects of fascial abrasion, fasciotomy, and fascial excision on cutaneous wound healing in cats AU - Mitsui, Akiko AU - Mathews, Kyle G. AU - Linder, Keith E. AU - Kruse, Meghan A. AU - Roe, Simon C. T2 - AMERICAN JOURNAL OF VETERINARY RESEARCH AB - OBJECTIVE-To evaluate the effects of fascial abrasion, fasciotomy, and fascial excision on cutaneous wound healing in cats. ANIMALS-Eight 1- to 3-year-old domestic shorthair cats. PROCEDURES-8 evenly spaced 4-cm(2) skin wounds were created on each cat's dorsum, and the underlying subcutaneous tissue was removed to expose the epaxial muscle fascia. Wounds were randomized to receive 1 of 4 treatments (2 wounds/treatment/cat): fascial abrasion, fasciotomy, fascial excision, or control treatment (muscle fascia not disturbed). Bandages were changed and digital photographs and acetate tracings of the wounds were obtained for planimetry daily for 1 week, every other day for 2 weeks, and then every third day for 3 weeks (ie, 40-day observation period). Digitized images were evaluated for granulation tissue formation, wound contraction (surface area measurements), and area of epithelialization. RESULTS-The epithelialized area and open and total wound areas did not differ among treatments at any time point. Time to the first appearance of granulation tissue was significantly shorter for all treatment groups, compared with that of the control group. Time to achieve granulation tissue coverage of wound base was significantly shorter following fasciotomy (9.6 days) and fascial excision (9.0 days), compared with that of control treatment (18.5 days) or abrasion (16.7 days). Numbers of wounds that developed exuberant granulation tissue following fascial excision (9/16) and control treatment (3/16) differed significantly. CONCLUSIONS AND CLINICAL RELEVANCE-Fasciotomy and fascial excision facilitated early granulation tissue development in cutaneous wounds in cats. In clinical use, these fascial treatments may expedite secondary wound closure or skin grafting. DA - 2009/4// PY - 2009/4// DO - 10.2460/ajvr.70.4.532 VL - 70 IS - 4 SP - 532-538 SN - 1943-5681 ER - TY - JOUR TI - Improving construction site runoff quality with fiber check dams and polyacrylamide AU - McLaughlin, R. A. AU - King, S. E. AU - Jennings, G. D. T2 - JOURNAL OF SOIL AND WATER CONSERVATION AB - Sediment and turbidity are among the most common pollutants affecting surface waters, resulting in reduced reservoir capacity, degradation of aquatic organism habitat, and decreased aesthetic value. Construction activities, including roadway projects, can be significant contributors to sediment loading in streams and lakes. We studied water quality in stormwater runoff from three systems for erosion and sediment control on two roadway projects in the North Carolina mountains. The first roadway project was divided into three experimental sections, each with one the following treatments installed in the adjacent drainage ditch: (1) the standard best management practice (BMP) consisting of narrow sediment traps in the ditch along with rock check dams, (2) fiber check dams (FCDs) consisting of a mix of straw wattles and coir logs, or (3) FCDs with granulated, anionic polyacrylamide (PAM) added to each. The second project was smaller and included only two of the experimental sections described above: (1) the standard BMPs and (2) FCDs with PAM. Significant reductions in turbidity and total suspended solids were obtained using the FCDs, particularly those with PAM added. At site 1, from June 2006 to March 2007, the average turbidity values for the stormwater runoff were 3,813 nephelometric turbidity units (NTU) for the standard BMPs, 202 NTU for the FCDs-only, and 34 NTU for the FCDs with PAM. Average turbidity in discharges at site 2 was reduced from 867 NTU for the standard BMPs to 115 NTU for the FCDs with PAM. Sediment loading at both sites was similarly reduced with the use of FCDs. At site 1, the standard BMPs lost an average of 428 kg (944 lb) of sediment per storm event compared to just 2.1 kg (4.6 lb) for the FCDs-only and 0.9 kg (2.0 lb) for the FCDs with PAM. At site 2, the standard BMPs lost an average of 3.3 kg (7.3 lb) per storm event compared with 0.8 kg (1.8 lb) for the FCDs with PAM. A conservative economic analysis suggests that the costs of the FCDs are lower than the standard BMPs. This study suggests that the use of FCDs with PAM can bring discharges from similar linear construction projects much closer to the regulatory guidelines for non-point source discharges than the current standard practices. DA - 2009/// PY - 2009/// DO - 10.2489/jswc.64.2.144 VL - 64 IS - 2 SP - 144-154 SN - 1941-3300 KW - check dams KW - erosion control KW - polyacrylamide (PAM) KW - sediment loading KW - turbidity reduction KW - wattles ER - TY - JOUR TI - Ethanol and acetate production by Clostridium ljungdahlii and Clostridium autoethanogenum using resting cells AU - Cotter, Jacqueline L. AU - Chinn, Mari S. AU - Grunden, Amy M. T2 - BIOPROCESS AND BIOSYSTEMS ENGINEERING DA - 2009/4// PY - 2009/4// DO - 10.1007/s00449-008-0256-y VL - 32 IS - 3 SP - 369-380 SN - 1615-7591 KW - Clostridium ljungdahlii KW - Clostridium autoethanaogenum KW - Ethanol KW - Acetate KW - Resting cells KW - Non-growing cells ER - TY - JOUR TI - Use of selection with recurrent backcrossing and QTL mapping to identify loci contributing to southern leaf blight resistance in a highly resistant maize line AU - Zwonitzer, John C. AU - Bubeck, David M. AU - Bhattramakki, Dinakar AU - Goodman, Major M. AU - Arellano, Consuelo AU - Balint-Kurti, Peter J. T2 - THEORETICAL AND APPLIED GENETICS DA - 2009/3// PY - 2009/3// DO - 10.1007/s00122-008-0949-2 VL - 118 IS - 5 SP - 911-925 SN - 1432-2242 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-61649093980&partnerID=MN8TOARS ER - TY - JOUR TI - Oxidant generation and toxicity enhancement of aged-diesel exhaust AU - Li, Qianfeng AU - Wyatt, Anna AU - Kamens, Richard M. T2 - ATMOSPHERIC ENVIRONMENT AB - Diesel exhaust related airborne Particulate Matter (PM) has been linked to a myriad of adverse health outcomes, ranging from cancer to cardiopulmonary disease. The underlying toxicological mechanisms are of great scientific interest. A hypothesis under investigation is that many of the adverse health effects may derive from oxidative stress, initiated by the formation of reactive oxygen species (ROS) within affected cells. In this study, the main objective was to determine whether aged-diesel exhaust PM has a higher oxidant generation and toxicity than fresh diesel exhaust PM. The diesel exhaust PM was generated from a 1980 Mercedes-Benz model 300SD, and a dual 270 m3 Teflon film chamber was utilized to generate two test atmospheres. One side of the chamber is used to produce ozone–diesel exhaust PM system, and another side of the chamber was used to produce diesel exhaust PM only system. A newly optimized dithiothreitol (DTT) method was used to assess their oxidant generation and toxicity. The results of this study showed: (1) both fresh and aged-diesel exhaust PM had high oxidant generation and toxicity; (2) ozone–diesel exhaust PM had a higher toxicity response than diesel exhaust PM only; (3) the diesel exhaust PM toxicity increased with time; (4) the optimized DTT method could be used as a good quantitative chemical assay for oxidant generation and toxicity measurement. DA - 2009/2// PY - 2009/2// DO - 10.1016/j.atmosenv.2008.11.018 VL - 43 IS - 5 SP - 1037-1042 SN - 1873-2844 KW - Diesel particle KW - Dithiothreitol (DTT) method KW - Redox active species KW - Oxidant generation and toxicity KW - Particular matter ER - TY - JOUR TI - Growing Duckweed to Recover Nutrients from Wastewaters and for Production of Fuel Ethanol and Animal Feed AU - Cheng, Jay J. AU - Stomp, Anne-M. T2 - CLEAN-SOIL AIR WATER AB - Abstract Lemnaceae or duckweed is an aquatic plant that can be used to recover nutrients from wastewaters. The grown duckweed can be a good resource of proteins and starch, and utilized for the production of value‐added products such as animal feed and fuel ethanol. In the last eleven years we have been working on growing duckweed on anaerobically treated swine wastewater and utilizing the duckweed for fuel ethanol production. Duckweed strains that grew well on the swine wastewater were screened in laboratory and greenhouse experiments. The selected duckweed strains were then tested for nutrient recovery under laboratory and field conditions. The rates of nitrogen and phosphorus uptake by the duckweed growing in the laboratory and field systems were determined in the study. The mechanisms of nutrient uptake by the duckweed and the growth of duckweed in a nutrient‐limited environment have been studied. When there are nutrients (N and P) available in the wastewater, duckweed takes the nutrients from the wastewater to support its growth and to store the nutrients in its tissue. When the N and P are completely removed from the wastewater, duckweed can use its internally stored nutrients to keep its growth for a significant period of time. A modified Monod model has been developed to describe nitrogen transport in a duckweed‐covered pond for nutrient recovery from anaerobically treated swine wastewater. Nutrient reserve in the duckweed biomass has been found the key to the kinetics of duckweed growth. Utilization of duckweed for value‐added products has a good potential. Using duckweed to feed animals, poultry, and fish has been extensively studied with promising results. Duckweed is also an alternative starch source for fuel ethanol production. Spirodela polyrrhiza grown on anaerobically treated swine wastewater was found to have a starch content of 45.8% (dry weight). Enzymatic hydrolysis of the duckweed biomass with amylases yielded a hydrolysate with a reducing sugar content corresponding to 50.9% of the original dry duckweed biomass. Fermentation of the hydrolysate using yeast gave an ethanol yield of 25.8% of the original dry duckweed biomass. These results indicate that the duckweed biomass can produce significant quantities of starch that can be readily converted into ethanol. DA - 2009/1// PY - 2009/1// DO - 10.1002/clen.200800210 VL - 37 IS - 1 SP - 17-26 SN - 1863-0650 KW - Biofuels KW - Duckweed KW - Livestock feed production KW - Renewables KW - Wastewater treatment ER - TY - JOUR TI - Bioretention technology: Overview of current practice and future needs AU - Davis, A. P. AU - Hunt, W. F. AU - Traver, R. G. AU - Clar, M. T2 - Journal of Environmental Engineering (New York, N.Y.) AB - Bioretention, or variations such as bioinfiltration and rain gardens, has become one of the most frequently used storm-water management tools in urbanized watersheds. Incorporating both filtration and infiltration, initial research into bioretention has shown that these facilities substantially reduce runoff volumes and peak flows. Low impact development, which has a goal of modifying postdevelopment hydrology to more closely mimic that of predevelopment, is a driver for the use of bioretention in many parts of the country. Research over the past decade has shown that bioretention effluent loads are low for suspended solids, nutrients, hydrocarbons, and heavy metals. Pollutant removal mechanisms include filtration, adsorption, and possibly biological treatment. Limited research suggests that bioretention can effectively manage other pollutants, such as pathogenic bacteria and thermal pollution, as well. Reductions in pollutant load result from the combination of concentration reduction and runoff volume attenuation, linking water quality and hydrologic performance. Nonetheless, many design questions persist for this practice, such as maximum pooling bowl depth, minimum fill media depth, fill media composition and configuration, underdrain configuration, pretreatment options, and vegetation selection. Moreover, the exact nature and impact of bioretention maintenance is still evolving, which will dictate long-term performance and life-cycle costs. Bioretention usage will grow as design guidance matures as a result of continued research and application. DA - 2009/// PY - 2009/// DO - 10.1061/(asce)0733-9372(2009)135:3(109) VL - 135 IS - 3 SP - 109-117 ER - TY - JOUR TI - Analysis of functional traits in reconfigured channels: implications for the bioassessment and disturbance of river restoration AU - Tullos, Desiree D. AU - Penrose, David L. AU - Jennings, Gregory D. AU - Cope, W. Gregory T2 - JOURNAL OF THE NORTH AMERICAN BENTHOLOGICAL SOCIETY AB - Channel reconfiguration is a popular but controversial approach to river restoration, and ecological responses to channel reconfiguration have not been rigorously assessed. We compared physical-habitat variables, taxonomic and functional-trait diversities, taxonomic composition, and functional-trait abundances between 24 pairs of upstream (control) and downstream reconfigured (restored) reaches in 3 catchment land uses (urban, agricultural, rural) across the North Carolina Piedmont. We asked how environmental filters and functional species traits might provide insight to biological responses to restoration. Taxonomic and functional-trait differences between control and restored reaches suggest that restoration affected aquatic assemblages only in agricultural and rural catchments. Our results highlight 2 important aspects of channel reconfiguration as a restoration practice. First, responses to restoration differ between agricultural/rural and urban catchments, possibly because of modified hydrological regimes caused by urbanization. Second, we find evidence that channel reconfiguration disturbs food and habitat resources in stream ecosystems. Taxa sensitive to disturbance were characteristic of control reaches, whereas insensitive taxa were characteristic of restored reaches. Abundances of traits related to reproduction (voltinism, development, synchronization of emergence, adult life span), mobility (occurrence in drift, maximum crawling rate, swimming ability), and use of resources (trophic and habitat preferences) differed significantly between control and recently restored reaches. Our results suggest that taxa in restored habitats are environmentally selected for traits favored in disturbed environments. Our work suggests how functional-trait approaches could benefit the practice of river restoration when used to target restoration activities and to develop informed expectations regarding recovery following restoration activities. DA - 2009/3// PY - 2009/3// DO - 10.1899/07-122.1 VL - 28 IS - 1 SP - 80-92 SN - 0887-3593 KW - benthic macroinvertebrate KW - functional traits KW - channel reconfiguration KW - disturbance KW - bioassessment KW - river restoration ER - TY - JOUR TI - Soil Organic Matter Effects on Phosphorus Sorption: A Path Analysis AU - Kang, Jihoon AU - Hesterberg, Dean AU - Osmond, Deanna L. T2 - SOIL SCIENCE SOCIETY OF AMERICA JOURNAL AB - While P sorption in mineral soils has been extensively studied, P sorption behavior in organic‐rich soils is less known. This study was conducted to determine the relationships between Langmuir P sorption maxima ( S max ) and selected physicochemical properties of soils, with particular emphasis on organic matter (OM) content. The S max values were determined for 72 soil samples from the North Carolina Coastal Plain, along with pH, clay and OM contents, oxalate‐extractable P (P ox ), Al (Al ox ), and Fe (Fe ox ), and Mehlich 3 extractable P (P M3 ), Al (Al M3 ), and Fe (Fe M3 ). Path analysis was used to examine direct and indirect effects of soil properties on S max In the oxalate path analysis, the direct effects of clay, Al ox , and Fe ox on S max were significant in the order Al ox > clay > Fe ox ( P < 0.05). The S max was highly influenced by the indirect effect of Al ox and Fe ox through OM content. A two‐piece segmented linear relationship existed between S max and OM and the regression slope in soils with OM ≤ 49 g kg −1 was 10‐fold greater than that for soils with OM > 49 g kg −1 This finding suggested that noncrystalline or organically bound Al and Fe in the soils with OM > 49 g kg −1 is less effective for P sorption than in the soils with lower OM content. In the Mehlich 3 path analysis, the direct effects of clay, OM, and Al M3 on S max were significant in the order Al M3 > OM > clay ( P < 0.05) while the direct effect of Fe M3 on S max was not significant. Oxalate may be better suited than Mehlich 3 as an extractant for predicting P sorption capacity in the Coastal Plain soils. DA - 2009/// PY - 2009/// DO - 10.2136/sssaj2008.0113 VL - 73 IS - 2 SP - 360-366 SN - 1435-0661 ER - TY - JOUR TI - Shades of gray: the world of quantitative disease resistance AU - Poland, Jesse A. AU - Balint-Kurti, Peter J. AU - Wisser, Randall J. AU - Pratt, Richard C. AU - Nelson, Rebecca J. T2 - TRENDS IN PLANT SCIENCE AB - A thorough understanding of quantitative disease resistance (QDR) would contribute to the design and deployment of durably resistant crop cultivars. However, the molecular mechanisms that control QDR remain poorly understood, largely due to the incomplete and inconsistent nature of the resistance phenotype, which is usually conditioned by many loci of small effect. Here, we discuss recent advances in research on QDR. Based on inferences from analyses of the defense response and from the few isolated QDR genes, we suggest several plausible hypotheses for a range of mechanisms underlying QDR. We propose that a new generation of genetic resources, complemented by careful phenotypic analysis, will produce a deeper understanding of plant defense and more effective utilization of natural resistance alleles. A thorough understanding of quantitative disease resistance (QDR) would contribute to the design and deployment of durably resistant crop cultivars. However, the molecular mechanisms that control QDR remain poorly understood, largely due to the incomplete and inconsistent nature of the resistance phenotype, which is usually conditioned by many loci of small effect. Here, we discuss recent advances in research on QDR. Based on inferences from analyses of the defense response and from the few isolated QDR genes, we suggest several plausible hypotheses for a range of mechanisms underlying QDR. We propose that a new generation of genetic resources, complemented by careful phenotypic analysis, will produce a deeper understanding of plant defense and more effective utilization of natural resistance alleles. a host–pathogen interaction that results in disease (the host is susceptible). a resistance gene that has become ineffective. a host–pathogen interaction that does not result in disease (the host is resistant). two amino acid sequence motifs commonly found in resistance genes. inbred lines that differ at only a small genomic region. the combination of a specific host species and pathogen species. proteins that identify molecules, such as flagellin or chitin components, that are associated with microbial pathogens. resistance that is expressed as a reduction in disease, rather than as the absence of disease. a locus with an effect on QDR. a locus with an effect on a quantitative trait (i.e. a trait showing continuous variation). an inbred line produced from an initial cross followed by continuous inbreeding; populations of RILs are often used for QTL-mapping studies. the phenomenon of a resistant cultivar becoming susceptible owing to changes in the pathogen race. putative genes that share sequence similarity with known R-genes. the phenomenon of a resistance gene becoming ineffective in a crop variety. DA - 2009/1// PY - 2009/1// DO - 10.1016/j.tplants.2008.10.006 VL - 14 IS - 1 SP - 21-29 SN - 1878-4372 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-58149490801&partnerID=MN8TOARS ER - TY - JOUR TI - Performance evaluation of six different aerosol samplers in a particulate matter generation chamber AU - Park, J.-M. AU - Rock, J.C. AU - Wang, L. AU - Seo, Y.-C. AU - Bhatnagar, A. AU - Kim, S. T2 - Atmospheric Environment AB - The present study was carried out with the aim of evaluating the performance of six different aerosol samplers in terms of mass concentration, particle size distribution, and mass fraction for the international size-sampling conventions. The international size-sampling criteria were defined as inhalable, thoracic, and respirable mass fractions with 50% cutoff at an aerodynamic equivalent diameter of 100 μm, 10 μm, and 4 μm, respectively. Two Andersen, four total suspended particulate (TSP), two RespiCon, four PM10, two DustTrak, and two SidePak samplers were selected and tested to quantitatively estimate human exposure in a carefully controlled particulate matter (PM) test chamber. The overall results indicate that (1) Andersen samplers underestimate total suspended PM and overestimate thoracic and respirable PM due to particle bounce and carryover between stages, (2) TSP samplers provide total suspended PM as reference samplers, (3) TSP samplers quantified by a coulter counter multisizer provide no information below an equivalent spherical diameter of 2 μm and therefore underestimate respirable PM, (4) RespiCon samplers are free from particle bounce as inhalable samplers but underestimate total suspended PM, (5) PM10 samplers overestimate thoracic PM, and (6) DustTrak and SidePak samplers provide relative PM concentrations instead of absolute PM concentrations. DA - 2009/// PY - 2009/// DO - 10.1016/j.atmosenv.2008.09.028 VL - 43 IS - 2 SP - 280-289 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-57949096309&partnerID=MN8TOARS ER - TY - JOUR TI - Modeling denitrification in a tile-drained, corn and soybean agroecosystem of Illinois, USA AU - David, Mark B. AU - Del Grosso, Stephen J. AU - Hu, Xuetao AU - Marshall, Elizabeth P. AU - McIsaac, Gregory F. AU - Parton, William J. AU - Tonitto, Christina AU - Youssef, Mohamed A. T2 - BIOGEOCHEMISTRY DA - 2009/3// PY - 2009/3// DO - 10.1007/s10533-008-9273-9 VL - 93 IS - 1-2 SP - 7-30 SN - 0168-2563 KW - Crop yields KW - Mollisol KW - N(2)O KW - Nitrate KW - Soil moisture ER - TY - JOUR TI - Mitigation of impervious surface hydrology using bioretention in North Carolina and Maryland AU - Li, H. AU - Sharkey, L. J. AU - Hunt, W. F. AU - Davis, A. P. T2 - Journal of Hydrologic Engineering AB - As an increasingly adopted storm water best management practice to remedy hydrologic impairment from urban imperviousness, bioretention facilities need rigorous field performance research and monitoring to confirm performance and improve design and maintenance recommendations. This study investigated hydrologic performance at six bioretention cells in Maryland [College Park (CP), a 181m2 cell, 50–80cm media depth, monitored for 22 events, and Silver Spring (SS), a 102m2 cell, 90cm media depth, monitored for 60 events] and North Carolina [Greensboro (G1 and G2), each approximately 317m2, 120cm media depth, both monitored for 46 events, and Louisburg (L1=surface area of 162m2, L2=surface area of 99m2); each had 50–60cm fill depths, monitored for 31 and 33 events, respectively] over 10–15month periods. Outflow from each cell was recorded and inflow was either recorded or calculated from rainfall data. In Louisburg, L2 was lined with an impermeable membrane to eliminate exfiltration while L1 was unlined to allow both exfiltration and evapotranspiration. Results indicate that bioretention facilities can achieve substantial hydrologic benefits through delaying and reducing peak flows and decreasing runoff volume. A large cell media volume: drainage area ratio, and adjustments to the drainage configuration appear to improve the performance. Media layer depth may be the primary design parameter controlling hydrologic performance. Performance diminishes as rainfall depths increase and rainfall durations become longer. Annual water budget analysis suggests that approximately 20–50% of runoff entering the bioretention cells was lost to exfiltration and evapotranspiration. DA - 2009/// PY - 2009/// DO - 10.1061/(ASCE)1084-0699(2009)14:4(407) VL - 14 IS - 4 SP - 407-415 ER - TY - JOUR TI - Effect of microbial pretreatment on enzymatic hydrolysis and fermentation of cotton stalks for ethanol production AU - Shi, Jian AU - Sharma-Shivappa, Ratna R. AU - Chinn, Mari AU - Howell, Noura T2 - BIOMASS & BIOENERGY AB - The potential of microbial pretreatment of cotton stalks by Phanerochaete chrysosporium to degrade lignin and facilitate fuel ethanol production was investigated under two culture conditions: submerged cultivation (SmC) and solid state (SSC) cultivation. Although microbial pretreatments showed significant lignin degradation (LD) (19.38% and 35.53% for SmC and SSC, respectively), a study on hydrolysis and fermentation of the microbial-pretreated cotton stalks showed no increase in cellulose conversion (10.98% and 3.04% for SmC and SSC pretreated samples, respectively) compared to untreated cotton stalks (17.93%). Solid state cultivation demonstrated better selectivity of 0.82 than 0.70 with submerged pretreatment. Washing of pretreated cotton stalks did not significantly increase cellulose conversion. However, heating and washing remarkably improved (P<0.05) cellulose conversion to 14.94% and 17.81% for SmC and SSC 14 day pretreatment, respectively. Ethanol yields, up to 0.027 g ethanol g−1 initial cotton stalks, were low for all untreated and pretreated samples mainly due to the low cellulose conversion. Although potential and some critical aspects of fungal pretreatment using P. chrysosporium have been explored in this study, additional investigation is still required especially to improve the selectivity for preferential LD and to optimize hydrolysis efficiency. The mechanism of catalytic binding of cellulolytic enzymes to cotton stalks as affected by the presence of fungal mycelia also warrants further study. DA - 2009/1// PY - 2009/1// DO - 10.1016/j.biombioe.2008.04.016 VL - 33 IS - 1 SP - 88-96 SN - 1873-2909 KW - Gossypium hirsutum L KW - Pretreatment KW - Phanerochaete chrysosporium KW - Lignin KW - Fuel ethanol KW - Cellobiose KW - Submerged cultivation KW - Solid state cultivation ER - TY - JOUR TI - Asphalt parking lot runoff nutrient characterization for eight sites in North Carolina, USA AU - Passeport, E. AU - Hunt, W. F. T2 - Journal of Hydrologic Engineering AB - The objectives of this study were to characterize asphalt parking lot runoff quality and determine factors influencing nutrient concentrations and loads. Event mean concentrations (EMCs) and loads were measured from eight asphalt parking lots in North Carolina using automated flow meters and rain gauges. The number of water quality samples collected varied from 11 to 26 per site. EMCs and loads were statistically analyzed for six nutrient forms: total nitrogen, total Kjeldahl nitrogen, ammonia-nitrogen, nitrate-nitrogen, total phosphorus, and ortho-phosphate. The mean EMCs (in mg/L) were 1.57, 1.19, 0.32, 0.36, 0.19 and 0.07, respectively. Nitrogen species’ concentrations were slightly lower than those from highway runoff found in the literature; whereas, phosphorus EMCs were similar to those in highway runoff. Current load prediction models, generally based on highway or roadway nutrient concentrations, are therefore expected to over-estimate nitrogen loads from asphalt parking lots. Spring and summer presented the highest EMCs and loads, respectively. Significant seasonal differences in concentration (p<0.05) were found mainly between spring and the other three seasons, while loads in summer differed from those of fall and winter. In an attempt to determine the factors affecting EMCs and loads, Pearson correlation tests and multiple linear regression analyses were performed. Strong correlations were found among the variables of each group of factors referred to as climate, physical characteristics and surrounding land use. Rainfall depth, catchment area, the percentage of asphalt and natural surrounding land use were good predictors of nutrient concentrations and loads. DA - 2009/// PY - 2009/// DO - 10.1061/(ASCE)1084-0699(2009)14:4(352) VL - 14 IS - 4 SP - 352-361 ER - TY - JOUR TI - Surgical correction of severe strabismus and enophthalmos secondary to zygomatic arch fracture in a dog AU - Konrade, Kricket A. AU - Clode, Alison B. AU - Michau, Tammy M. AU - Roe, Simon C. AU - Trumpatori, Brian J. AU - Krug, William V. AU - Gilger, Brian C. T2 - VETERINARY OPHTHALMOLOGY AB - Abstract A grossly displaced segmental zygomatic arch fracture with marked ventro‐lateral deviation of the left globe was diagnosed in a 3‐month‐old male German Shepherd dog following a bite injury. The fracture was approached via a modified lateral orbitotomy and a fragment of the lacrimal bone removed. The rostral portion of the fracture was stabilized with a 5‐hole 2.0 dynamic compression plate bone plate. The surgical correction achieved sufficient skeletal fixation for proper anatomical reduction of the globe and excellent cosmetic and functional outcomes. DA - 2009/// PY - 2009/// DO - 10.1111/j.1463-5224.2008.00689.x VL - 12 IS - 2 SP - 119-124 SN - 1463-5224 KW - dog KW - fracture KW - miniplate fixation KW - orbital rim ER - TY - JOUR TI - Sampling and Analytical Variability Associated with the Determination of Total Aflatoxins and Ochratoxin A in Powdered Ginger Sold As a Dietary Supplement in Capsules AU - Trucksess, Mary W. AU - Whitaker, Thomas B. AU - Weaver, Carol M. AU - Slate, Andrew AU - Giesbrecht, Francis G. AU - Rader, Jeanne I. AU - Betz, Joseph M. T2 - JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY AB - The U.S. Food and Drug Administration is studying the need to monitor dietary supplements for mycotoxins such as total aflatoxins and ochratoxin A. An effective mycotoxin-monitoring program requires knowledge of the sampling and analytical variability associated with the determination of total aflatoxins (AF) and ochratoxin A (OTA) in dietary supplements. Three lots of ginger sold as a powder in capsule form and packaged in individual bottles were analyzed for both AF and OTA. The total variability associated with measuring AF and OTA in powdered ginger was partitioned into bottle-to-bottle, within bottle, and analytical variances. The variances were estimated using a nested design. For AF and OTA, the within-bottle variance associated with the 5 g laboratory sample size was the largest component of variability accounting for about 43% and 85% of the total variance, respectively; the analytical variance accounted for about 34% and 9% of the total variability, respectively; and the bottle-to-bottle variance accounted for about 23% and 7% of the total variance, respectively. When the total variance is converted into the coefficient of variation (CV or standard deviation relative to the mean concentration), the CV is lower for AF (16.9%) than OTA (24.7%). DA - 2009/1/28/ PY - 2009/1/28/ DO - 10.1021/jf8017854 VL - 57 IS - 2 SP - 321-325 SN - 0021-8561 KW - Sampling KW - analytical uncertainty KW - aflatoxins KW - ochratoxin A KW - ginger capsules KW - dietary supplements ER - TY - JOUR TI - Performance of a bioretention area and a level spreader-grass filter strip at two highway sites in North Carolina AU - Line, D. E. AU - Hunt, W. F. T2 - Journal of Irrigation and Drainage Engineering AB - The pollutant removal efficiency of a bioretention area and a level spreader-grass filter strip implemented at North Carolina highway facilities was assessed. The assessment consisted of monitoring inflow, outflow, and on-site rainfall for at least 13 storm events. Monitoring included continuous discharge measurement and collecting and analyzing flow-proportional samples for each event. All samples were analyzed for solids, turbidity, and nitrogen and phosphorus forms and selected samples were analyzed for metals. The level spreader-grass filter strip had the best overall efficiency with load reduction efficiencies in all pollutants ranging from 24 to 83% and the highest reduction for total suspended solids (TSS). Much of the efficiency of this best management practice can be attributed to the 49% reduction in runoff volume from inflow to outflow. Pollutant reduction efficiencies for the bioretention area ranged from −254 to 76% with the highest reduction for TSS. The lowest or large negative efficiency was for nitrate+nitrite nitrogen (NO2+3–N). The increase in NO2+3–N likely resulted from a combination of nitrogen additions within the cell and conversion of other forms of nitrogen to NO2+3–N. Statistical analyses suggested that all of the mass reductions for the grass filter strip and many of those for the bioretention area were significant. DA - 2009/// PY - 2009/// DO - 10.1061/(ASCE)0733-9437(2009)135:2(217) VL - 135 IS - 2 SP - 217-224 ER - TY - JOUR TI - Switchgrass for bioethanol and other value-added applications: A review AU - Keshwani, Deepak R. AU - Cheng, Jay J. T2 - BIORESOURCE TECHNOLOGY AB - Switchgrass is a promising feedstock for value-added applications due to its high productivity, potentially low requirements for agricultural inputs and positive environmental impacts. The objective of this paper is to review published research on the conversion of switchgrass into bioethanol and other value-added products. Environmental benefits associated with switchgrass include the potential for carbon sequestration, nutrient recovery from runoff, soil remediation and provision of habitats for grassland birds. Pretreatment of switchgrass is required to improve the yields of fermentable sugars. Based on the type of pretreatment, glucose yields range from 70% to 90% and xylose yields range from 70% to 100% after hydrolysis. Following pretreatment and hydrolysis, ethanol yields range from 72% to 92% of the theoretical maximum. Other value-added uses of switchgrass include gasification, bio-oil production, newsprint production and fiber reinforcement in thermoplastic composites. Future prospects for research include increased biomass yields, optimization of feedstock composition for bioenergy applications, and efficient pentose fermentation to improve ethanol yields. DA - 2009/2// PY - 2009/2// DO - 10.1016/j.biortech.2008.09.035 VL - 100 IS - 4 SP - 1515-1523 SN - 1873-2976 KW - Switchgrass KW - Bioenergy KW - Ethanol KW - Lignocelluloses KW - Pretreatment ER - TY - JOUR TI - Evaluation of the DRAINMOD-N II model for predicting nitrogen losses in a loamy sand under cultivation in south-east Sweden AU - Salazar, Osvaldo AU - Wesstrom, Ingrid AU - Youssef, Mohamed A. AU - Skaggs, R. Wayne AU - Joel, Abraham T2 - AGRICULTURAL WATER MANAGEMENT AB - The DRAINMOD–N II model (version 6.0) was evaluated for a cold region in south-east Sweden. The model was field-tested using four periods between 2002 and 2004 of climate, soil, hydrology and water quality data from three experimental plots, planted to a winter wheat–sugarbeet–barley–barley crop rotation and managed using conventional and controlled drainage. DRAINMOD–N II was calibrated using data from a conventional drainage plot, while data sets from two controlled drainage plots were used for model validation. The model was statistically evaluated by comparing simulated and measured drain flows and nitrate–nitrogen (NO3–N) losses in subsurface drains. Soil mineral nitrogen (N) content was used to evaluate simulated N dynamics. Observed and predicted NO3–N losses in subsurface drains were in satisfactory agreement. The mean absolute error (MAE) in predicting NO3–N drainage losses was 0.16 kg N ha−1 for the calibration plot and 0.21 and 0.30 kg N ha−1 for the two validation plots. For the simulation period, the modelling efficiency (E) was 0.89 for the calibration plot and 0.49 and 0.55 for the validation plots. The overall index of agreement (d) was 0.98 for the calibration plot and 0.79 and 0.80 for the validation plots. These results show that DRAINMOD–N II is applicable for predicting NO3–N losses from drained soil under cold conditions in south-east Sweden. DA - 2009/2// PY - 2009/2// DO - 10.1016/j.agwat.2008.08.008 VL - 96 IS - 2 SP - 267-281 SN - 1873-2283 KW - Controlled drainage KW - Subsurface drainage KW - DRAINMOD KW - Modelling KW - Nitrate loads ER - TY - JOUR TI - Acidic processing of mineral dust iron by anthropogenic compounds over the north Pacific Ocean AU - Solmon, F. AU - Chuang, P. Y. AU - Meskhidze, N. AU - Chen, Y. T2 - JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES AB - Atmospheric processing of mineral aerosol by anthropogenic pollutants may be an important process by which insoluble iron can be transformed into soluble forms and become available to oceanic biota. Observations of the soluble iron fraction in atmospheric aerosol exhibit large variability, which is poorly represented in models. In this study, we implemented a dust iron dissolution scheme in a global chemistry transport model (GEOS‐Chem). The model is applied over the North Pacific Ocean during April 2001, a period when concentrations of dust and pollution within the east Asia outflow were high. Simulated fields of many key chemical constituents compare reasonably well with available observations, although some discrepancies are identified and discussed. In our simulations, the production of soluble iron varies temporally and regionally depending on pollution‐to‐dust ratio, primarily due to strong buffering by calcite. Overall, we show that the chemical processing mechanism produces significant amounts of dissolved iron reaching and being deposited in remote regions of the Pacific basin, with some seasonal variability. Simulated enhancements in particulate soluble iron fraction range from 0.5% to 6%, which is consistent with the observations. According to our simulations, ∼30% to 70% of particulate soluble iron over the North Pacific Ocean basin can be attributed to atmospheric processing. On the basis of April 2001 monthly simulations, sensitivity tests suggest that doubling SO 2 emissions can induce a significant increase (13% on average, up to 40% during specific events) in dissolved iron production and deposition to the remote Pacific. We roughly estimate that half of the primary productivity induced by iron deposition in a north Pacific high‐nutrient low‐chlorophyll region is due to soluble iron derived from anthropogenic chemical processing of Asian aerosol. DA - 2009/1/24/ PY - 2009/1/24/ DO - 10.1029/2008jd010417 VL - 114 SP - SN - 2169-8996 ER -