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Registros recuperados: 92 | |
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Lentz, R.D.; Westermann, D.T.. |
Nutrient losses in furrow irrigation runoff potentially increase when soils are amended with manure. We evaluated the effect of tillage, water soluble polyacrylamide (WSPAM) and irrigation management on runoff water quality during the first furrow irrigation on a calcareous silt loam soil, which had received 45 Mg/ha (dry wt.) dairy manure applied in the fall. In Exp. 1 the amended soil was rototilled and irrigated that fall; furrow inflows were either treated with 10 mg/L WSPAM injected into furrow inflows only during furrow advance (Fall-WSPAM), or were untreated (Fall-Control). In Exp. 2 the first irrigation on the amended soil was delayed until the following spring and treatments included rototilled WSPAM (Spring-WSPAM) and untreated rototilled... |
Tipo: Article |
Palavras-chave: Water management; Water quality; Furrow irrigation. |
Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1384/1/1359.pdf |
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Lentz, R.D.. |
Standard water quality analysis methods recommend that sediment-laden runoff waters sampled to determine dissolved nutrient concentrations be filtered immediately after collection. Few research studies have examined the influence of delayed filtration on sample stability or nutrient loss assessments. Twenty eight runoff water volumes were collected from 3 irrigation furrows during a 12-h irrigation set. Four subsamples of each volume were obtained; 2 were filtered (45 µm) in the field and the other 2 were filtered 10 days later, with or without boric acid treatment (1 mL saturated H3BO3 solution per 100 mL sample). All samples were refrigerated at 4 deg. C. Dissolved reactive P (DRP), NO3-N, and NH4-N concentrations were measured in all filtered... |
Tipo: Article |
Palavras-chave: Nitrogen; Phosphorous; Nutrients. |
Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1516/1/1480.pdf |
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Lentz, R.D.; Freeborn, L.L.. |
Seepage from water streams into unlined channels determines the proportion of water distributed to adjacent soil for plant use or soil or groundwater recharge or conveyed to downstream reaches. We conducted a laboratory study to determine how sediment type (none, clay, and silt), sediment concentration (0, 0.5, and 2 g Lj1 ), and water-soluble anionic polyacrylamide (PAM) concentration (0, 0.4, and 2 mg Lj1 ) inf luences seepage loss of irrigation water (electrical conductivity = 0.04 S mj1 ; sodium adsorption ratio = 2.2) from unlined channels in silt loam soil. In a minif lume, a preformed channel with 7% slope was supplied with 40 mL minj1 simulated irrigation water inf lows containing the different treatment combinations. Runoff and... |
Tipo: Article |
Palavras-chave: Sediment; Seepage reduction; Mass Import - autoclassified (may be erroneous). |
Ano: 2007 |
URL: http://eprints.nwisrl.ars.usda.gov/68/5/1233.pdf |
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Lentz, R.D.; Ippolito, J.A.. |
When added to soils, carbon-rich biochar derived from the pyrolysis of woody materials can sequester atmospheric carbon dioxide, mitigate climate change, and potentially increase crop productivity. However, research is needed to confirm the suitability and sustainability of biochar application to different soils. We applied four treatments (dry wt.) to an irrigated calcareous soil in Nov. 2008: control; stockpiled dairy manure, 18.8 Mg/ha; hardwood-derived biochar, 22.4 Mg/ha; and manure + biochar using previous rates. Nitrogen fertilizer was applied when needed (based on pre-season soil test N and crop requirements) in all plots and years with N mineralized from added manure included in this determination. Available soil nutrients (NH4-N, NO3-N, Olsen... |
Tipo: Article |
Palavras-chave: Corn / maize; Manure; Calcareous soil; Soil. |
Ano: 2012 |
URL: http://eprints.nwisrl.ars.usda.gov/1459/1/1424.pdf |
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Lehrsch, G.A.; Brown, B.; Lentz, R.D.; Johnson-Maynard, J.L.; Leytem, A.B.. |
To profitably produce sugarbeet (Beta vulgaris L.) by maximizing recoverable sucrose, producers must effectively manage added nitrogen (N), whether it be from inorganic sources such as urea or from often readily available and sometimes less expensive organic sources such as manure or composted manure. Our multi-site study’s objective was to determine if equivalent sugarbeet root and sucrose yields could be achieved when substituting composted dairy cattle manure or stockpiled manure for conventional N (urea) fertilizer. Treatments at Site 1 (Parma, ID), for 2 y included a control (no N applied), urea (202 kg N/ha), compost (1089 and 2175 kg total N/ha), and manure (350 and 701 kg total N/ha). Treatments at Site 2 (Kimberly, ID), were a control, urea (82 kg... |
Tipo: Article |
Palavras-chave: Sugarbeet; Manure; Chemistry; Nitrogen; Soil. |
Ano: 2015 |
URL: http://eprints.nwisrl.ars.usda.gov/1560/1/1516.pdf |
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Lentz, R.D.; Westermann, D.T.; Lehrsch, G.A.. |
Few studies have comprehensively examined nutrient losses in runoff from furrow-irrigated fields, but the rising cost of fertilizer and finite nature of the resource encourages further research. A 2-yr experiment measured runoff losses of sediment, particulate P and N, and dissolved NO3-N, NH4-N, K, and reactive P (DRP) from fertilized, manured, or non-amended fields. Average nutrient losses were substantial, including 15.6 lbs ac/yr dissolved N, P, and K and 73.6 lbs ac/yr particulate N and P. The cost or replacing these nutrients with inorganic fertilizers was not trivial, at $54.69 ac/yr. Relative to non-amended soil, manure increased dissolved K, NO3-N, and DRP in runoff by 2.1x, 1.5x, and 2.7x, respectively. Other experiments evaluated the... |
Tipo: Conference or Workshop Item |
Palavras-chave: Furrow irrigation; Runoff losses; Nutrients; Sediment. |
Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1518/1/1482.pdf |
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Lentz, R.D.; Lehrsch, G.A.. |
Little is known about inorganic fertilizer or manure effects on organic carbon (OC) and inorganic C (IC) losses from a furrow irrigated field, particularly in the context of other system C gains or losses. In 2003 and 2004, we measured dissolved organic and inorganic C (DOC, DIC), particulate OC and IC (POC, PIC) concentrations in irrigation inflow, runoff, and percolation waters (6-7 irrigations/y); C inputs from soil amendments and crop biomass; harvested C; and gaseous C emissions from field plots cropped to silage corn (Zea mays L.) in southern Idaho. Annual treatments included: (M) 13 (y 1) and 34 Mg/ha (y 2) stockpiled dairy manure; (F) 78 (yr 1) and 195 kg N/ha (y 2) inorganic N fertilizer; or (NA) no amendment--control. The mean annual total C... |
Tipo: Article |
Palavras-chave: Corn / maize; Dissolved Organic Carbon (DOC); Manure. |
Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1546/1/1504.pdf |
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Registros recuperados: 92 | |
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