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| Registros recuperados: 601 | |
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| Mayland, H.F.. |
| The higher fatty acids (HFA) are important plant constituents that are implicated in the grass tetany hazard in livestock. A method is given whereby a technician can analyze 12 forage samples daily for HFA content. The method consists of saponifying the plant material in ethanol and KOH and extracting the subsequently acidified HFA with petroleum ether. The petroleum ether phase is evaporated and the HFA residue is dissolved in ethanol and then titrated with standardized isobutanolic KOH in the absence of Oxygen by using an Nitrogen atmosphere. A standard plant sample, analyzed over a 37-day period, had a mean of 136 mmol H+kg ± 4.5, where 0.1 mmol H+ℓ palmitic standard was determined with an accuracy of 99 ± 1.9%. |
| Tipo: Article |
Palavras-chave: Chemistry; Forage quality; Grass forage. |
| Ano: 1979 |
URL: http://eprints.nwisrl.ars.usda.gov/1442/1/436.PDF |
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| Ippolito, J.A.; Barbarick, K.A.; Brobst, R.B.. |
| Predicting trace metal solid phase speciation changes associated with long-term biosolids land application is important for understanding and improving environmental quality. Biosolids were surface-applied (no incorporation; 0, 1, 2, 5, 10, and 15 tons per acre) to a semi-arid grassland in 1991 (single) or again in 2002 (repeated). In July 2003, soils were obtained from the 0-3, 3-6, and 6-12-inch depths in all plots. Using soil pH, soluble anion and cation concentrations from 0.01 moles per liter calcium chloride extractions, and dissolved organic carbon content, copper and zinc associated with minerals, hydrous ferric oxide, or dissolved organic phases was modeled using Visual Minteq. Scanning electron microscopy and energy dispersive x-ray analysis... |
| Tipo: Article |
Palavras-chave: Chemistry; Soil. |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1556/1/1512.pdf |
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| Griggs, T.C.; McAdam, J.W.; Mayland, H.F.; Burns, J.C.. |
| Herbage soluble carbohydrate (SC) levels vary diurnally and livestock intake can be higher for herbage harvested or allocated to animals in the evening than in the morning. Few assessments of SC and digestibility patterns have been made during sward depletion in rotationally stocked orchardgrass (Dactylis glomerata L.). We tested the hypothesis that simulated evening daily pasture allocation increases 24-h mean herbage SC and digestibility levels relative to morning allocation. Total nonstructural carbohydrate (TNC) and in vitro true dry matter digestibility (IVTDMD) levels were compared during 24-h clipping sequences initiated at 1900 h (PM) and 0700 h (AM). Sward height was progressively reduced from 40 to 8 cm at 6-h intervals in October,... |
| Tipo: Article |
Palavras-chave: Chemistry; Mass Import - autoclassified (may be erroneous). |
| Ano: 2005 |
URL: http://eprints.nwisrl.ars.usda.gov/16/1/1163.pdf |
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| Lentz, R.D.; Ippolito, J.A.; Spokas, K.A.. |
| Aluminum-based water treatment residuals (Al-WTR) have a strong affinity to sorb phosphorus. In a proof-of-concept greenhouse column study, Al-WTR was surface-applied at 0, 62, 124, and 248 Mg/ha to 15 cm of soil on top of 46 cm of sand; Al-WTR rates were estimated to capture 0, 10, 20, and 40 years of phosphorus from an urban watershed entering an engineered wetland in Boise, Idaho, USA. Creeping red fescue (Festuca rubra) was established in all columns; one set of columns received no Al-WTR or plants. After plant establishment, once per week over a 12-week period, ~1.0 pore volumes of ~0.20 mg phosphorus/L was added to each column. Infiltration rates were measured, leachate was collected and analyzed for soluble phosphorus, and fescue yield,... |
| Tipo: Article |
Palavras-chave: Chemistry; Soil quality. |
| Ano: 2015 |
URL: http://eprints.nwisrl.ars.usda.gov/1592/1/1550.pdf |
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| Robbins, Charles W.; Gavlak, R.G.. |
| This publication is designed to help identify salt- and sodium-affected soils, the salt or sodium sources, how to take soil and water samples, how to reduce the harmful effects of salts and sodium and where to get advice in making reclamation and management decisions for each situation. Salt- and sodium-affected soils, and waters used for irrigation, present a complex combination of problems and possible solutions. It is not the intent here to cover all technical aspects or possible treatment approaches available, but rather to give a simplified overview of what should be considered in diagnosing and managing salt- and sodium-affected soils and irrigation waters. Since summarizing the effects of salt and sodium on soils and plants is... |
| Tipo: Technical Bulletin |
Palavras-chave: Chemistry; Mass Import - autoclassified (may be erroneous). |
| Ano: 1989 |
URL: http://eprints.nwisrl.ars.usda.gov/1123/1/681.pdf |
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| Tarkalson, D.D.; Payero, J.O.; Ensley, S.M.; Shapiro, C.A.. |
| Nitrate leaching from agricultural soils can increase groundwater nitrate concentrations. The objectives of the study were to assess the accumulation and movement of nitrate in the soil profile over a 2-year period under deficit irrigation conditions following a one time application of N in cattle feedlot manure and commercial fertilizer to corn at rates to achieve yield goals expected under conditions of full irrigation. Cattle manure and ammonium nitrate were applied in 2002 at the University of Nebraska recommended rate (1M and 1F ; respectively) and cattle manure was applied at twice the recommended rate (2M) for N for the 2002 corn (Zea mays L.) crop. The recommended rate was based on expected yields under full irrigation. The manure N... |
| Tipo: Article |
Palavras-chave: Chemistry; Fertilizer; Nitrogen; Mass Import - autoclassified (may be erroneous). |
| Ano: 2006 |
URL: http://eprints.nwisrl.ars.usda.gov/59/1/1220.pdf |
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| Registros recuperados: 601 | |
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