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| Registros recuperados: 167 | |
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| 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 |
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| Lehrsch, G.A.; Sojka, R.E.. |
| Differences in irrigation water quality may affect the water repellency of soils treated or untreated with surfactants. Using simulated irrigations, we evaluated water quality and surfactant application rate effects upon the water repellency of a Quincy sand (Xeric Torripsamment). We used a split plot design with two irrigation water qualities, three surfactant application rates, two irrigations, and twelve sampling depths as fixed effects, with four replications. Each water quality x rate x irrigation combination was a main plot and depth was a repeated-measures subplot. A slightly water repellent Quincy soil (average water drop penetration time, WDPT, of 2.5 s) was packed in 25-mm lifts (or layers) to a bulk density of 1.6 Mg/cubic m into 0.15-m-high... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation; Water management. |
| Ano: 2011 |
URL: http://eprints.nwisrl.ars.usda.gov/1430/1/1400.pdf |
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| Sojka, R.E.; Entry, J.A.. |
| We compared the efficacy of matrix based fertilizers (MBFs) formulated to reduce NO 3 -, NH4+ , and total phosphorus (TP) leaching, with Osmocoate® 14-14-14, a conventional commercial slow release fertilizer (SRF), and with an unamended control in greenhouse column studies. The MBF formulations covered a range of inorganic N and P in compounds that are relatively loosely bound (MBF1) to more moderately bound (MBF2) and more tightly bound compounds (MBF3) mixed with Al(SO 4)3 H2O and/or Fe2(SO4 )3 and with high ionic exchange compounds starch, chitosan and lignin. When N and P are released, the chemicals containing these nutrients in the MBF temporarily bind N and P to a Al(SO4 )3 H2O and/or Fe2(SO4 )3 starch- chitosan- lignin matrix. One milligram... |
| Tipo: Conference or Workshop Item |
Palavras-chave: Fertilizer; Mass Import - autoclassified (may be erroneous). |
| Ano: 2007 |
URL: http://eprints.nwisrl.ars.usda.gov/856/1/1224.pdf |
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| Lehrsch, G.A.; Lentz, R.D.; Bjorneberg, D.L.; Sojka, R.E.. |
| Soil can be eroded by sprinkler or surface irrigation. Once sprinkler droplet kinetic energy detaches soil, overland flow transports the sediment downslope and off-site. Protecting the soil surface, increasing sprinkler wetted diameters, and tilling to increase infiltration and thereby lessen overland flow are effective control measures. Runoff minimization and management are key to reducing erosion induced by either sprinkler or surface irrigation. Slowing furrow stream velocities with mulch or crop residues reduces the flow’s hydraulic shear and, in turn, detachment of soil from furrow wetted perimeters. Stabilizing surface soil with, for example, polyacrylamide, bio-polymers, or whey keeps soil in place and helps maintains acceptable water quality in... |
| Tipo: Article |
Palavras-chave: Sprinkler irrigation; Erosion; Water management. |
| Ano: 2014 |
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| Registros recuperados: 167 | |
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