|
|
|
| Registros recuperados: 274 | |
|
| |
|
| |
|
| |
|
|
| King, B.A.; Winward, T.W.; Bjorneberg, D.L.. |
| Kinetic energy of water droplets has a substantial effect on development of a soil surface seal and infiltration rate of bare soil. Methods for measuring sprinkler droplet size and velocity needed to calculate droplet kinetic energy have been developed and tested over the past 50 years, each with advantages, disadvantages, and limitations. A laser precipitation meter and photographic method were used to measure droplet size and velocity from an impact sprinkler at three pressures and one nozzle size. Significant differences in cumulative volume drop size distributions derived from the two measurement methods were found, especially at the highest operating pressure. Significant differences in droplet velocities were found between measurement methods as... |
| Tipo: Conference or Workshop Item |
Palavras-chave: Sprinkler irrigation; Soil water (soil moisture); Water management. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1577/1/1533.pdf |
| |
|
| |
|
| |
|
| |
|
| |
|
|
| Freeman, C.L.; Ippolito, J.A.; Stromberger, M.E.; Barbarack, K.A.; Redente, E.F.. |
| This study was conducted to determine the effect of biosolids and lime on reclamation of a heavily contaminated metal site. Within the Superfund area near Leadville, CO, biosolids and lime were amended (1998) to a 1 ha site at rates of 240 Mg per ha each. In 2006, soil samples were collected on a 10 m x 10 m grid to a depth of 30 cm across the site. Basic soil analysis included pH, EC, total C and N, inorganic and organic C, and NO3-N and NH4-N. A sequential fractionation for metal contaminants of concern (Cd, Cr, Fe, Pb, Mn, and Zn) identified associations with: 1) soluble/exchangeable; 2) specifically sorbed/weakly bound; 3) non-crystalline Fe/Mn oxides; 4) crystalline Fe/Mn oxides and organically complexed; 5) residual organic; and 6) residual... |
| Tipo: Conference or Workshop Item |
Palavras-chave: Soil. |
| Ano: 2008 |
URL: http://eprints.nwisrl.ars.usda.gov/1433/1/1346.pdf |
| |
|
| |
|
| |
|
|
| Bjorneberg, D.L.; Strelkoff, T.; Clemmens, A.J.; Lee, J.H.. |
| There continues to be a need to predict furrow irrigation erosion to estimate on- and off-site impacts of irrigation management. The objective of this paper is to review the current state of furrow erosion prediction technology considering four models: SISL, WEPP, WinSRFR and APEX. SISL is an empirical model for predicting annual soil loss from furrow irrigated fields. SISL could potentially be a useful model if a new method was developed to calculate base soil loss for areas other than southern Idaho where it was developed. The WEPP model uses physically-based equations to predict erosion in irrigation furrows, which are assumed to be the same as rills. Primary difficulties with the WEPP model are defining erodibility parameters for furrow irrigation and... |
| Tipo: Conference or Workshop Item |
Palavras-chave: Furrow irrigation; Soil. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1570/1/1526.pdf |
| |
|
|
| 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 |
| |
|
| |
|
| |
|
|
| King, B.A.; Bjorneberg, D.L.. |
| The kinetic energy of discrete water drops impacting a bare soil surface is generally observed to lead to a drastic reduction in water infiltration rate due to soil surface seal formation. Under center-pivot sprinkler irrigation, kinetic energy transferred to the soil prior to crop canopy development can have a substantial effect on seasonal runoff and soil erosion. In the design of center-pivot irrigation systems, selection of sprinklers with minimum applied kinetic energy could potentially minimize the seasonal runoff and erosion hazard. The size and velocity of drops from common rotating spray-plate sprinklers center-pivot sprinklers with flow rates of approximately 40 and 20 L/ min were measured using a laser in the laboratory. The data were used to... |
| Tipo: Conference or Workshop Item |
Palavras-chave: Sprinkler irrigation; Center pivot. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1426/1/1396.pdf |
| |
|
| |
| Registros recuperados: 274 | |
|
|
|
