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| Registros recuperados: 14 | |
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| Bjorneberg, D.L.; Ippolito, J.A.; Koehn, A.C.. |
| Water, sediment and nutrients flowing into and out of the 82,000 ha Twin Falls,ID irrigation tract were measured from 2005 to 2008. Approximately 80% of the water flowing into the watershed was irrigation water diverted from the Snake River. About 40% of the watershed inflow returned to the Snake River. Much of this return flow was water from subsurface drain tiles and tunnels that drain shallow groundwater. Converting from furrow to sprinkler irrigation, improved irrigation management, and constructed sediment ponds have reduced sediment loss from 460 kg/ha in 1971 to <100 kg/ha in 2005. In 2007 and 2008, more sediment and phosphorus entered the watershed than returned to the Snake River. Diverting irrigation water into the watershed removed 6300 Mg of... |
| Tipo: Conference or Workshop Item |
Palavras-chave: Irrigation control; Runoff losses; Nutrient losses; Nutrients; Soil. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1571/1/1527.pdf |
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| Bjorneberg, D.L.; Leytem, A.B.; Ippolito, J.A.; Koehn, A.C.. |
| Watersheds utilizing surface water for irrigation often return a portion of the water to a water body. This irrigation return flow often includes sediment and nutrients that reduce the quality of the receiving water body. Research in the 82,000 ha Upper Snake Rock (USR) watershed from 2005 to 2008 showed that, on average, water diverted from the Snake River annually supplied 547 kg/ha of total suspended sediment (TSS), 1.1 kg/ha of total phosphorus (TP) and 0.50 kg/ha of dissolved phosphorus (DP) to the irrigation tract. Irrigation return flow from the USR watershed contributed 414 kg/ha of TSS, 0.71 kg/ha of TP and 0.32 kg/ha of DP back to the Snake River. Significantly more TP flowed into the watershed than returned to the Snake River while there was no... |
| Tipo: Article |
Palavras-chave: Irrigation control; Nutrients. |
| Ano: 2015 |
URL: http://eprints.nwisrl.ars.usda.gov/1586/1/1543.pdf |
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| Koehn, A.C.; Lehrsch, G.A.; Busscher, W.J.; Evans, D.E.; King, B.A.; Stieneke, D.L.; Sojka, R.E.. |
| Agricultural crops grown in southern Idaho are furrow or sprinkler irrigated. Therefore, the soil experiences several wetting and drying cycles each growing season that can contribute to changes in aggregate tensile strength and friability. The objective of the research was to evaluate the influence of irrigation on soil structural properties. Four furrow irrigated fields were sampled at the top and bottom of the field, in the furrow and on the bed location of the furrow. Five sprinkler irrigated fields were sampled at 0-5 and 5-15 cm depth and at the top and bottom of the field. Results from this study indicate that differences in tensile strength in furrow irrigated fields were only evident soon after irrigation; otherwise, there were few differences in... |
| Tipo: Article |
Palavras-chave: Furrow irrigation; Sprinkler irrigation. |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1567/1/1523.pdf |
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| Koehn, A.C.; Leytem, A.B.; Bjorneberg, D.L.. |
| Inverse dispersion models are useful tools for estimating emissions from animal feeding operations, waste storage ponds, and manure application fields. Atmospheric stability is an important input parameter to such models. The objective of this study was to compare emission rates calculated with a backward Lagrangian stochastic (bLS) inversedispersion model (WindTrax) using three different methods for calculating atmospheric stability: sonic anemometer, gradient Richardson number, and Pasquill-Gifford (P-G) stability class. Ammonia and methane emission data from a compost yard at a 10,000-cow dairy were used for the comparisons. Overall, average emission rates were not significantly different among the stability methods. Emission rates correlated well... |
| Tipo: Article |
Palavras-chave: Air Emissions. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1490/1/1454.pdf |
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| Lehrsch, G.A.; Sojka, R.E.; Koehn, A.C.. |
| Little is known regarding a soil aggregate's tensile strength response to surfactants that may be applied to alleviate soil water repellency. Two laboratory investigations were performed to determine surfactant effects on the tensile strength of 1) Ap horizons of nine wettable, agricultural soils collected from across the continental U.S., and 2) two of the nine soils (Latahco and Rad silt loams from the Pacific Northwest) that were sampled at two depths (5 and 15 mm) after being sprinkler irrigated. Along with an untreated control, three surfactants (an alkyl polyglycoside, an ethylene oxide/propylene oxide block copolymer, and a blend of the two) were spray applied by hand at rates of 0, 1, 1.63, 3.35, 4.79, or 8.14 kg active ingredient ha1 to 1)... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation. |
| Ano: 2012 |
URL: http://eprints.nwisrl.ars.usda.gov/1467/1/1432.pdf |
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| 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 |
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| 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 |
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| Registros recuperados: 14 | |
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