|
|
|
| Registros recuperados: 40 | |
|
|
| King, B.A.; Dungan, R.S.; Bjorneberg, D.L.. |
| Wind drift and evaporation losses (WDELs) are an often discussed topic in regards to center pivot sprinkler irrigation efficiency. Opinions on the magnitude of WDELs vary widely, in part due to the wide variation in WDEL values published in the literature. The magnitude of WDELs reported in the literature range from 2 to 45%. The common technique employed to measure WDEL is to use catch cans and compare the measured volume of catch with the volume of water applied based on sprinkler nozzle size, operating pressure and spacing with the difference being WDEL. The inaccuracies of catch cans resulting from wind effects on catch efficiency and evaporation of water from the catch can prior to measurement have led to the wide range in WDEL reported in the... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation; Center pivot. |
| Ano: 2012 |
URL: http://eprints.nwisrl.ars.usda.gov/1470/1/1435.pdf |
| |
|
|
| Leytem, A.B.; Dungan, R.S.; Bjorneberg, D.L.; Koehn, A.C.. |
| Concentrated dairy operations emit trace gases such as ammonia (NH3), methane (CH4), and nitrous oxide (N2O) to the atmosphere. The implementation of air quality regulations in livestock-producing states increases the need for accurate on-farm determination of emission rates. The objective of this study was to determine the emission rates of NH3, CH4, and N2O from the open-freestall and wastewater pond source areas on a commercial dairy located in southern Idaho. Gas concentrations and wind statistics were measured each month and used with an inverse dispersion model to calculate emission rates. Average emissions per cow per day from the open-freestall source area were 0.10 kg NH3 and 0.47 kg CH4. Average emissions from the wastewater ponds (g m-2 d-1)... |
| Tipo: Article |
Palavras-chave: Air Emissions; Animal Production; Manure Management. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1501/1/1464.pdf |
| |
|
|
| Dungan, R.S.; Bjorneberg, D.L.; Leytem, A.B.. |
| In this study we conducted simulated spray irrigation events of dairy wastewater to assess the impact of pressure and sprinkler type upon post-sprinkler culturable microorganism concentrations. Dairy wastewater was sampled before and after it was pumped through sprinklers typically used on center pivot irrigation systems. Three different sprinklers types were used at three different operating pressures to give a range of water drop sizes. The microorganisms quantified in this study were total coliforms, Escherichia coli, Clostridium perfringens, heterotrophic bacteria, and coliphage. In most cases the pre- and post-sprinkler concentrations were determined to be statistically similar, suggesting that culturable viability was not affected when wastewater... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation; Manure. |
| Ano: 2011 |
URL: http://eprints.nwisrl.ars.usda.gov/1444/1/1409.pdf |
| |
|
|
| Dungan, R.S.; Leytem, A.B.. |
| Endotoxins are derived from gram-negative bacteria and are a potential respiratory health risk for animals and humans. To determine the potential for endotoxin transport from a large open-lot dairy, total airborne endotoxin concentrations were determined at an upwind location (background) and five downwind locations on three separate days. The downwind locations were situated at of the edge of the lot, 200 and 1390 m downwind from the lot, and downwind from a manure composting area and wastewater holding pond. When the wind was predominantly from the west, the average endotoxin concentration at the upwind location was 24 endotoxin units (EU) m?3, whereas at the edge of the lot on the downwind side it was 259 EU m?3. At 200 and 1390 m downwind... |
| Tipo: Article |
Palavras-chave: Manure. |
| Ano: 2009 |
URL: http://eprints.nwisrl.ars.usda.gov/1330/1/1307.pdf |
| |
|
|
| Dungan, R.S.; Kim, Jong-Shik; Makama, Mfundi; Petito, Janine; Park, Nyun-Ho; Cohan, F.M.. |
| The objective of this study was to phylogenetically analyze microorganisms from the domains Bacteria and Archaea in hypersaline sediment from Death Valley National Park. Using domain-specific primers, a region of the 16S rRNA gene was amplified using PCR, and the product was subsequently used to create a clone library. A total of 243 bacterial clones, 99 archaeal clones, and 209 bacterial isolates were examined. The 243 clones from Bacteria were affiliated with the following groups: the Bacilli (59 clones) and Clostridia (1) of the Firmicutes, Bacteroidetes (90), Proteobacteria (27), Cyanobacteria (18), Gemmatimonadetes (41), candidate division OP1 (5), Actinobacteria (1), and the Deinococcus-Thermus division (1). Within the class Bacilli, 46 of 59... |
| Tipo: Article |
Palavras-chave: Soil. |
| Ano: 2012 |
URL: http://eprints.nwisrl.ars.usda.gov/1453/1/1418.pdf |
| |
|
|
| Dungan, R.S.; Kim, J.; Weon, H.; Leytem, A.B.. |
| The purpose of this research was to characterize the structure and composition of bacterial communities in sandy loam and silty clay soils amended with 30% spent sand from iron, aluminum, and steel foundries. All spent foundry sand (SFS) blends were grown with or without perennial ryegrass and samples were collected at 4 weeks and 6 months. Regions of the 16S rRNA gene were amplified using PCR and subsequently analyzed by DGGE and sequenced for bacterial identification and phylogenetic classification. Cluster analyses of PCR-DGGE banding patterns revealed that SFS blends from week 4 and month 6 produced unique clusters, with most ryegrass treatments clustering away from those without ryegrass. The diversity of the bacterial community revealed that it... |
| Tipo: Article |
Palavras-chave: Soil; Soil quality. |
| Ano: 2009 |
URL: http://eprints.nwisrl.ars.usda.gov/1339/1/1316.pdf |
| |
|
|
| Leytem, A.B.; Dungan, R.S.; Bjorneberg, D.L.; Koehn, A.C.. |
| Concentrated animal feeding operations emit trace gases such as ammonia (NH3), methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) to the atmosphere. The implementation of air quality regulations in livestock-producing states increases the need for accurate on-farm determination of emission rates. The objective of this study was to determine the emission rates of NH3, CH4, CO2, and N2O from three source areas (open-lots, lagoon, compost) on a commercial dairy located in southern Idaho. Average emissions per cow per day from the open-lots were 0.12 kg NH3, 0.49 kg CH4, 26.9 kg CO2, and 0.01 kg N2O. Average emissions from the lagoon (g per m square per day) were 1.5 g NH3, 132 g CH4, 391 g CO2, and 0.36 g N2O. Average emissions from the compost... |
| Tipo: Article |
Palavras-chave: Manure; Animal; Chemistry. |
| Ano: 2011 |
URL: http://eprints.nwisrl.ars.usda.gov/1392/3/1365.pdf |
| |
|
|
| Leytem, A.B.; Dungan, R.S.. |
| livestock operations can potentially affect air quality at local, regional, and even global scales. These pollutants, many of which are generated through various anthropogenic activities, are being increasingly scrutinized by regulatory authorities. Regulation of emissions from livestock production systems will ultimately increase on farm costs, which will then be passed onto consumers. Therefore, it is essential that scientifically based emission factors are developed for on-farm emissions of air quality constituents to improve inventories and assign appropriate reduction targets. To generate a larger database of on-farm emissions, the USDA–ARS created the workgroup Livestock GRACEnet (Greenhouse gas Reduction through Agricultural Carbon Enhancement... |
| Tipo: Article |
Palavras-chave: Air Emissions; Application guidelines; Chemistry. |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1542/1/1499.pdf |
| |
|
|
| Dungan, R.S.; Leytem, A.B.. |
| Purple sulfur bacteria (PSB) in livestock wastewaters use reduced sulfur compounds and simple volatile organics as growth factors. As a result, the presence of PSB in manure storage ponds or lagoons is often associated with reduced odors. In this study, our objectives were to use molecular- and culture-based techniques to evaluate the occurrence of PSB in eight dairy wastewater ponds and identify physiochemical properties that might cause blooms to occur. Community DNA was extracted from composited wastewater samples, then the PufM gene and a conservative sequence for Chromatiaceae were amplified. Analysis of the 16S rRNA genes from denaturing gradient gel electrophoresis (DGGE) bands indicated that all of the dairy wastewater ponds contained sequences... |
| Tipo: Article |
Palavras-chave: Air Emissions. |
| Ano: 2015 |
URL: http://eprints.nwisrl.ars.usda.gov/1604/1/1562.pdf |
| |
|
|
| Dayton, E.A.; Whitacre, S.D.; Dungan, R.S.; Basta, N.T.. |
| Abstract As of 2007, of the 2,000 United States foundries, 93% produce ferrous or aluminum castings, generating 9.4 million tons of non-hazardous spent foundry sand (SFS) annually. Only 28% of the SFS is beneficially used. The U.S. EPA Resource Conservation Challenge identifies SFS as a priority material for beneficial use, with soil blending as a potential reuse option. The objectives of this work were to measure: (1) select chemical and physical properties important to soil quality and function and (2) total and soluble elemental content of 39 SFSs, in order to evaluate SFS suitability as a component in manufactured soils. Total elemental concentration of the SFS was lower than natural background soil levels for most elements analyzed, suggesting limited... |
| Tipo: Article |
Palavras-chave: Soil. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1359/1/1336.pdf |
| |
|
|
| Dungan, R.S.; Leytem, A.B.; Bjorneberg, D.L.. |
| In this study, we monitored total airborne endotoxins at upwind and downwind sites at a large open-lot dairy each month for a year. At the upwind site, the average airborne concentration was 28.5 endotoxin units (EU) m-3, while at the downwind edge of the lot and 200 m from the lot edge, the average concentrations were 169 and 72 EU m-3, respectively. At the downwind edge of the lot, there was a significant correlation between the airborne endotoxin concentration and wind speed or air temperature. A comparison between total and inhalable airborne endotoxin concentrations, near the end of the study, revealed no significant differences between the two endotoxin collection methods. Our data suggest that endotoxin exposure can be reduced as one increases their... |
| Tipo: Article |
Palavras-chave: Animal. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1368/1/1351.pdf |
| |
|
|
| Dungan, R.S.. |
| Airborne endotoxin in occupational environments are a potential respiratory hazard to individuals. In this study, total and inhalable airborne endotoxin samples were collected via filtration from inside animal housing units and downwind from agricultural production sites and a wastewater treatment plant. Filter extracts were then diluted to examine the effect of interfering substances on the kinetic Limulus amebocyte lysate (LAL) assay. In most cases, the overall endotoxin concentration was shown to decrease with increasing dilution up to 1,000-fold, suggesting the presence of enhancing substances in the filter extracts. This dilution dependent effect was most prominent in the inhalable endotoxin samples, while total endotoxin samples displayed little... |
| Tipo: Article |
Palavras-chave: Air Emissions; Endotoxins. |
| Ano: 2011 |
URL: http://eprints.nwisrl.ars.usda.gov/1410/1/1380.pdf |
| |
|
|
| Ippolito, J.A.; Stromberger, M.E.; Lentz, R.D.; Dungan, R.S.. |
| Biochar may improve nutrient retention when applied to soils, so co-applying biochar with manure may be synergistically beneficial to soils. In a laboratory incubation study, dairy manure (2% by weight) and a hardwood-based, fast pyrolysis biochar was applied (0, 1, 2, and 10% by weight) to a calcareous soil. Destructive sampling occurred at 1, 2, 3, 4, 5, 6 and 12 months, and monitored for changes in soil chemistry, water content, microbial respiration, bacterial populations, and microbial community structure. Increasing biochar application rate improved the soil water content, which may be beneficial in limited irrigation or rainfall areas. Biochar application increased soil organic carbon content and plant-available iron and manganese, while a... |
| Tipo: Article |
Palavras-chave: Soil. |
| Ano: 2015 |
URL: http://eprints.nwisrl.ars.usda.gov/1596/1/1554.pdf |
| |
|
|
| Bougouin, Adeline; Leytem, A.B.; Dijkstra, Jan; Dungan, R.S.; Kebreab, Ermias. |
| Nitrogen (N) excreted in urine by dairy cows can be potentially transformed to ammonia (NH3) and emitted to the atmosphere. Dairy production contributes to NH3 emission, which can create human respiratory problems and odor issues, reduces manure quality, and is an indirect source of nitrous oxide (N2O). The objective of this study was to (i) investigate environmental factors and measurement method that influence NH3 from dairy housing, and (ii) identify key explanatory variables in the prediction of NH3 emissions from dairy barns using a meta-analytical approach. Data from 25 studies were used for the preliminary analysis and data from 10 studies reporting 87 treatment means were used for the meta-analysis. Season, flooring type, manure handling and... |
| Tipo: Article |
Palavras-chave: Air Emissions; Animal Production; Animal health; Manure. |
| Ano: 2016 |
URL: http://eprints.nwisrl.ars.usda.gov/1624/1/1581.pdf |
| |
|
| |
|
|
| Leytem, A.B.; Dungan, R.S.; Bjorneberg, D.L.. |
| The volatilization of NH3 from dairy production facilities is not only a loss of valuable N, but also an air quality concern because NH3 plays a role in the formation of airborne particulate matter, which can be a health hazard. The ambient NH3 concentrations over several seasons at 3 locations (open lots, compost yard, lagoon) throughout a large openlot dairy were determined, as well as the spatial distribution of NH3 over the open-lot area. There was a significant main effect of location (P < 0.0001), which followed the trend of lot > lagoon = compost > background, with averages of 0.58, 0.33, 0.30, and 0.04 mg NH3/m3, respectively. The effect of weather and lot conditions on the spatial distribution of NH3 across the lots was evident, with... |
| Tipo: Article |
Palavras-chave: Manure; Soil; Animal. |
| Ano: 2009 |
URL: http://eprints.nwisrl.ars.usda.gov/1367/1/1344.pdf |
| |
|
|
| Alves, B.S.Q.; Dungan, R.S.; Carnin, R.L.P; Galvez, R.; de Carvalho Pinto, C.R.S.. |
| While most waste molding foundry sands (WFSs) are not hazardous in nature, regulatory agencies are often reluctant to permit their beneficial use in agricultural and geotechnical applications due to concerns over metal leaching. The objective of this study was to quantify total and Toxicity Characteristic Leaching Procedure (TCLP) metals in 16 waste sands from Brazilian ferrous foundries and assess their potential to leach metals to groundwater using a probabilistic model developed by the U.S. EPA. Total and TCLP metal concentrations in the non-hazardous sands fell within ranges as reported in the literature, although some of the leachate concentrations were found to exceed drinking water and groundwater maximum contaminant levels MCLs. Leachate values... |
| Tipo: Article |
Palavras-chave: Foundry sand. |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1537/1/1494.pdf |
| |
|
|
| Dungan, R.S.; Leytem, A.B.. |
| Endotoxins are derived from gram-negative bacteria and are a potent inducer of inflammatory reactions in the respiratory tract when inhaled. To assess daily fluctuations of airborne endotoxin and their potential for transport from dairies, endotoxin concentrations were monitored over an 8-h period at upwind (background) and downwind (5 m from edge of dairy) locations on three separate days at two dairies. The dairies consisted of an open-lot or an open-freestall production system, both of which were stocked with 10,000 milking cows. Upwind concentrations were stable throughout the sampling period, averaging between 1.2 and 36.8 endotoxin units (EU) m-3, whereas downwind concentration averages ranged from 179 to 989 EU-3. Downwind endotoxin concentrations... |
| Tipo: Article |
Palavras-chave: Air Emissions; Endotoxins; Manure Management. |
| Ano: 2011 |
URL: http://eprints.nwisrl.ars.usda.gov/1411/1/1381.pdf |
| |
|
|
| Leytem, A.B.; Dungan, R.S.. |
| The expansion of the dairy industry in southern Idaho has lead to increased application of manures to meet crop nutrient demands which can alter the uptake pattern of both macro- and micro-nutrients. A greenhouse study was conducted to determine the effects of dairy manure, composted dairy manure, and fertilizer (mono-ammonium phosphate, MAP) application on soil test phosphorus (P), microbial activity, and nutrient uptake by silage corn. Two Portneuf soils, having either a low or high soil test P concentration, were amended with the three treatments at four application rates (25, 50, 100, and 200 mg P kg-1) with four replications of each treatment in a randomized complete design. Treatments were incubated for two weeks, then planted with corn grown for... |
| Tipo: Article |
Palavras-chave: Chemistry; Composted manure; Manure. |
| Ano: 2011 |
URL: http://eprints.nwisrl.ars.usda.gov/1438/1/1405.pdf |
| |
|
|
| Dungan, R.S.; Leytem, A.B.. |
| Dairy wastewaters from storage ponds are commonly land applied to irrigate silage crops. Given that diverse microbial populations are associated with cattle feces, the objective of this study was to use a culture-independent approach to characterize Bacteria and Archaea in dairy wastewaters. Using domain-specific primers, a region of the 16S rRNA gene was amplified from pooled DNA extracts from 30 dairy wastewaters and subsequently used to create a clone library. A total of 152 bacterial clones were examined and sequence matches were affiliated with the following groups: Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria, and Synergistetes. Firmicutes was identified as the largest phylum representing up to 69% of the clone sequences. Of 167 clones... |
| Tipo: Article |
Palavras-chave: Manure; Water. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1511/1/1475.pdf |
| |
| Registros recuperados: 40 | |
|
|
|
