|
|
|
| Registros recuperados: 31 | |
|
|
| Entry, J.A.; Sojka, R.E.; Hicks, B.J.. |
| Water-soluble anionic polyacrylamide (PAM) is applied to millions of hectares worldwide as a highly effective erosion-preventing and infiltration-enhancing polymer, when applied at rates of 1 to 2 kg ha? 1 (i.e., 1 to 10 g m? 3) in furrow water. PAM degradation has not directly been measured in soil. We tested the ability of stable isotopes of C and N at natural abundance to estimate PAM degradation rates. Values of ?13C were related to anionic PAM concentration in a positive curvilinear relationship in a low-C, low-N, Durinodic Xeric Haplocalcid (Portneuf series) soil. The other soils with higher organic C or N concentrations did not show significant relationships between PAM concentrations and ?13C values. The ?15N values were not related to anionic PAM... |
| Tipo: Article |
Palavras-chave: Soil. |
| Ano: 2008 |
URL: http://eprints.nwisrl.ars.usda.gov/1276/1/1253.pdf |
| |
|
| |
|
| |
|
| |
|
|
| Sojka, R.E.; Entry, J.A.; Shewmaker, G.E.; Fuhrmann, J.J.. |
| Fossil fuel burning at the present rate, will double atmospheric carbon dioxide (CO 2 ) in this century, raising air temperature 1.5 to 5 °C. Sequestering carbon (C) in soil can reduce atmospheric CO2 concentration. We measured inorganic and organic C in southern Idaho soils having long term land use histories of native sagebrush vegetation (NSB), irrigated moldboard plowed crops (IMP), irrigated conservation- (chisel) tilled crops (ICT) and irrigated pasture systems (IP). Soil Organic C (SOC) decreased in the order IP>ICT>NSB>IMP. We used our findings to estimate potential amounts of organic C sequestered if irrigated agriculture expanded. If irrigated agricultural land was expanded by10°/0 worldwide and NSB was converted to ICT, 2.5 x 10... |
| Tipo: Conference or Workshop Item |
Palavras-chave: Mass Import - unclassified. |
| Ano: 2007 |
URL: http://eprints.nwisrl.ars.usda.gov/857/1/1225.pdf |
| |
|
| |
|
|
| Sojka, R.E.; Lentz, R.D.; Shainberg, I.; Trout, T.J.; Ross, C.W.; Robbins, C.W.; Entry, J.A.; Aase, J.K.; Bjorneberg, D.L.; Orts, W.J.; Westermann, D.T.; Morishita, D.W.; Watwood, M.E.; Spofford, T.L.; Barvenik, F.W.. |
| Tipo: Conference or Workshop Item |
Palavras-chave: Water-soluble PAM (WSPAM); Mass Import - autoclassified (may be erroneous). |
| Ano: 2000 |
URL: http://eprints.nwisrl.ars.usda.gov/943/1/1022.pdf |
| |
|
| |
|
| |
|
| |
|
| |
|
| |
|
|
| Ippolito, J.A.; Spackman, R.; Entry, J.A.; Sojka, R.E.. |
| Phosphorus-containing sediment entering surface water may degrade water quality and promote eutrophication. Grass is sometimes planted as a vegetated filter strip buffer along vulnerable receiving water to trap sediment and reduce the severity of phosphorus nutrient loading. However, eutrophication is still a problem in some waterways due to dissolved phosphorus leaching from senesced vegetation in grassed areas, independent of trapped sediment. A rainfall simulator (96 mm/h) was used to study the vegetative conditions under which losses of total dissolved phosphorus and filterable reactive phosphorus leaching are likely. Boxes containing a Portneuf silt loam soil (Xeric Haplocalcid) were planted with annual ryegrass (Lolium perenne) and cut at two... |
| Tipo: Article |
Palavras-chave: Runoff losses; Phosphorous. |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1545/1/1503.pdf |
| |
|
| |
| Registros recuperados: 31 | |
|
|
|
