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| Mamo, M.; Ippolito, J.A.; Kettler, T.; McCallister, D.L.; Morner, P.; Husmann, D.; Blankenship, E.. |
| Evolving computer technology offers opportunities for new online approaches in teaching methods and delivery. Well-designed online lessons should reinforce the critical need of the soil science discipline in today’s food, energy, and environmental issues, as well as meet the needs of the diverse clientele with interest in agricultural and/or environmental disciplines. The objectives of the project were to: (1) develop web-based lessons in soil genesis and development; and (2) evaluate an applications-principles model to teach soil science using case studies in agronomic, environmental, and ecological situations. Six principles lessons, along with three applications lessons, were developed for use by undergraduate earth science courses. Pre- and post-tests... |
| Tipo: Article |
Palavras-chave: Soil. |
| Ano: 2011 |
URL: http://eprints.nwisrl.ars.usda.gov/1452/1/1417.pdf |
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| Garcia, J.P.; Wortmann, C.S.; Mamo, M.; Drijber, R.; Tarkalson, D.. |
| Stratification of nutrient availability, especially of P, that develops with continuous no-till (NT) can affect runoff nutrient concentration and possibly nutrient uptake. The effects of composted manure application and one-time tillage of NT on the distribution of soil chemical properties, root colonization by arbuscular mycorrhizae (AM), and plant P uptake were determined. Research was conducted on Typic Argiudoll and Moffic Hapludaff soils under rainfed corn (Zea mays L.) or sorghum [Sorghum bicolor (L.) Moench.] rotated with soybean [Glycine max (L.) Men.] in eastern Nebraska. Tillage treatments included NT, disk, chisel, moldboard plow (MP), and mini-moldboard plow (MMP). Subplots had either 0 or 87.4 kg P ha -I- applied in compost before... |
| Tipo: Article |
Palavras-chave: Tillage; Mass Import - autoclassified (may be erroneous). |
| Ano: 2007 |
URL: http://eprints.nwisrl.ars.usda.gov/57/1/1219.pdf |
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| Biswas, S; Kranz, W.L.; Shapiro, C.A.; Mamo, M.; Bartlelt-Hunt, S.L.; Snow, D.D.; Tarkalson, D.D.; Shelton, D.P.; Mader, T.L.; van Donk, Simon J.; Zhang, T.C.. |
| Beef feedlot manure distributed to row crop production areas is a potential surface water contaminant source of the steroid hormones commonly used in beef cattle production. This article reports on research conducted at the University of Nebraska Haskell Agricultural Laboratory near Concord, Nebraska, in July 2009. Manure, collected from beef feedlot pens, was stockpiled for ten months prior to application to a row crop field. Previous research identified that the detection frequency of steroid hormones in beef manure varies greatly. Thus, a surrogate (17 alpha-ethynylestradiol, EE2) was applied at a rate of 75 g per ha to ensure detectable concentrations in surface runoff samples. EE2 was applied directly to beef cattle manure and to bare soil. The EE2... |
| Tipo: Article |
Palavras-chave: Manure Management; Tillage; Soil. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1554/1/1510.pdf |
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