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| Registros recuperados: 112 | |
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| Carter, David L.. |
| National concern about nitrate contamination of groundwater is raisin g many questions about the use of nitrogen fertilizer to grow high-quality crops. Some extremists are suggesting that commercial inorganic nitrogen fertilization should not be permitted. Such a limitation would seriously reduce crop productivity and farming profitability. We hope that it does not occur. However, the farming industry has become somewhat careless in nitrogen management because nitrogen fertilizer has been relatively cheap for the past couple of decades. Commonly, "a little extra nitrogen" has been applied to assure against a deficiency and less than maximum yield. in recent years. sugar beet growers have learned that such a practice can be costly because high... |
| Tipo: Article |
Palavras-chave: Practical farm efficiency; Mass Import - autoclassified (may be erroneous). |
| Ano: 1990 |
URL: http://eprints.nwisrl.ars.usda.gov/1228/1/698.pdf |
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| Tarkalson, D.D.; Ippolito, J.A.. |
| Development of best management practices can help improve inorganic nitrogen (N) availability to plants and reduce nitrate-nitrogen (NO3-N) leaching in soils. This study was conducted to determine the influence of the zeolite mineral Clinoptilolite (CL) additions on NO3-N and ammonium-nitrogen (NH4-N) in two common Pacific Northwest soils. The effects of CL application rate (up to 26.9 Mg ha-1) either band applied or mixed with a set rate of nitrogen (N) fertilizer on masses of NO3-N and NH4-N in leachate and soil was investigated in a column study using a Portneuf silt loam (coarse-silty mixed mesic Durixerollic Caliciorthid) and a Wolverine sand (Mixed, frigid Xeric Torripsamment). All treatments for each soil received a uniform application of N from... |
| Tipo: Article |
Palavras-chave: Practical farm efficiency; Nitrogen; Soil. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1431/1/1401.pdf |
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| Mayland, Hank; Shewmaker, Glenn. |
| Pouring a glass of milk is only a few steps away from pouring a glass of sunshine. Solar energy drives photosynthesis in green plants to produce simple sugars. When these plants are eaten by the cow, those sugars provide energy to rumen microorganisms which, in turn, provide energy to the cow for milk production. On warm sunshiny days, soluble sugars accumulate in plants faster than the plants can use them. At night, photosynthesis does not operate, and there is a loss of soluble sugars. This whole process results in a daily cycling of soluble sugars in the forage. Figure 1 clearly shows the gradual accumulation of plant sugar which builds as the day progresses. The drop in plant sugars occurs sometime after sunset. |
| Tipo: Article |
Palavras-chave: Practical farm efficiency; Mass Import - autoclassified (may be erroneous). |
| Ano: 2000 |
URL: http://eprints.nwisrl.ars.usda.gov/1234/1/1013.pdf |
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| Registros recuperados: 112 | |
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