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| Registros recuperados: 425 | |
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| Ducey, Tom; Ippolito, J.A.; Cantrell, K.B.; Novak, J.M.; Lentz, R.D.. |
| It has been demonstrated that soil amended with biochar, designed specifically for use as a soil conditioner, results in changes to the microbial populations that reside therein. These changes have been reflected in studies measuring variations in microbial activity, biomass, and community structure. Despite these studies, very few experiments have been performed examining microbial genes involved in nutrient cycling processes. Given the paucity of research in this area, we designed a six-month study in a Portneuf soil (coarse-silty, mixed, superactive, mesic Durinodic Xeric Haplocalcid) treated with three levels (1%, 2%, and 10% w/w ratio) of a biochar pyrolyzed from switchgrass (Panicum virgatum) at 350°C and steam activated at 800°C to measure the... |
| Tipo: Article |
Palavras-chave: Amendments; Chemistry; Nitrogen; Soil. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1517/1/1481.pdf |
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| Tarkalson, D.D.; Bjorneberg, D.L.. |
| Nutrient placement options with strip tillage (ST) can potentially improve plant nutrient utilization and increase crop yield compared to conventional fertilizer placement practices under conventional tillage (CT). The effects of tillage practice and nitrogen (N) and phosphorus (P) placement on grain yield, biomass yield (whole plant, sum of grain, cobs, and stover), and N and P uptake of field corn (Zea mays L.) were assessed on four sites during 2007 and 2009 at the USDA-ARS Northwest Irrigation & Soils Research Laboratory at Kimberly, ID. During each year, two locations (eroded and not eroded from furrow irrigation) were utilized as study locations. Band placement of fertilizer with ST increased corn grain yield by 12.5 percent (689 kg per ha) and... |
| Tipo: Article |
Palavras-chave: Fertilizer; Soil; Nitrogen; Phosphorous. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1383/1/1358.pdf |
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| Blecker, S.W.; STILLINGS, L.L.; AMACHER, M.C.; Ippolito, J.A.; DECRAOPPEO, N.M.. |
| Soil quality indices provide a means of distilling large amounts of data into a single metric that evaluates the soil’s ability to carry out key ecosystem functions. Primarily developed in agroecosytems, then forested ecosystems, we set out to develop and apply an index using the relation between soil organic matter and key soil abiotic and biotic properties in more semi-arid of the Western US arid systems impacted by different geologic mineralization types. We studied these relations in three different mineralization types: serpentine, acid sulfate and Cu/Mo porphyry systems at four different sites in California and Nevada. Soil samples were collected from undisturbed soils in both mineralized and nearby unmineralized terrane as well as waste rock and... |
| Tipo: Article |
Palavras-chave: Nitrogen; Soil. |
| Ano: 2012 |
URL: http://eprints.nwisrl.ars.usda.gov/1489/1/1453.pdf |
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| Dobermann, A.R.; Wortmann, C.S.; Ferguson, R.B.; Hergert, G.W.; Shapiro, C.A.; Tarkalson, D.D.; Walters, D.T.. |
| Nitrogen management recommendations may change as yield levels and efficiency of crop production increase. The mean yield with adequate nutrient availability in 32 irrigated corn (Zea mays L.) trials conducted across Nebraska to evaluate crop response to split-applied N was 14.8 Mg per ha. The mean economically optimal N rates (EONR) for irrigated corn varied with the fertilizer N to grain price ratio. At a fertilizer N:corn price ratio of 7, the EONR was 171, 122, and 93 kg per hectare, respectively, for cropping systems with corn following corn (CC), soybean (Glycine max L.) (CS), and drybean (Phaseolus vulgaris L.) (CD). At this price ratio the present University of Nebraska (UNL) recommendation procedure gave mean N recommendations that were 17.2,... |
| Tipo: Article |
Palavras-chave: Corn / maize; Nitrogen. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1415/1/1385.pdf |
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| Tarkalson, D.D.; Bjorneberg, D.L.. |
| The use of strip tillage and other conservation tillage practices are used to conserve soil and soil water through residue management and reduce tillage costs in many areas of the Corn Belt. However, in the Pacific Northwest these tillage practices are less common. Strip tillage is becoming more common in the sugar beet industry in southern Idaho and due to the high dairy cow populations, corn production is increasing. The dual use of strip tillage for sugar beet and corn production will likely continue to develop, increasing the need for strip tillage best management practices in this region. In this study we evaluated the effects of common and logical nitrogen and phosphorus placements with strip tillage and conventional tillage on grain yield on four... |
| Tipo: Article |
Palavras-chave: Tillage; Nitrogen; Phosphorous. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1388/3/1363.pdf |
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| Payero, J.O.; Tarkalson, D.D.; Irmak, S.. |
| Nitrate-Nitrogen (NO3 -N) losses to ground and surface water are an environmental and agronomic concern in modern crop production systems in the Central Great Plains. Monitoring techniques for nitrogen use in agricultural production are needed to increase crop yield, optimize nitrogen use, and reduce NO 3 -N leaching. Time domain reflectometry (TDR) could potentially be calibrated to continuously measure NO3 -N in soil and water. The objectives of this study were to: (1) evaluate the effect of different factors affecting the response of the bulk electrical conductivity (ECb) sensed by TDR, (2) compare the sensitivity and differences between vertically-installed and horizontally-installed probes for measuring NO3 -N leaching in the soil profile, and... |
| Tipo: Article |
Palavras-chave: Nitrogen; Research methodology; Mass Import - autoclassified (may be erroneous). |
| Ano: 2006 |
URL: http://eprints.nwisrl.ars.usda.gov/60/1/1221.pdf |
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| Moore, Amber; Tarkalson, D.D.. |
| Decomposition rates directly affect carbon and nitrogen ratios, which can affect nitrogen mineralization rates. The objective of this research is to determine the effect of tillage method and nitrogen rate on nitrogen available to sugar beets planted after a cereal crop. This two-year field study conducted in Kimberly, Idaho, consisted of three tillage methods (moldboard plow, chisel plow, and strip tillage), two tillage timings (fall and spring), and four fertilizer N rates plus a control. Soils from each plot were sampled shortly after nitrogen fertilization and incubated at average seasonal temperatures for Kimberly, Idaho to monitor nitrogen mineralization patterns. In 2008, we found that at N fertilizer rates of 0, 50, and 100 lbs N per acre,... |
| Tipo: Conference or Workshop Item |
Palavras-chave: Tillage; Nitrogen. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1387/3/1362.pdf |
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| Wortmann, C.C.; Shapiro, C.A.; Dobermann, Achim; Ferguson, Richard; Hergert, G; Walters, Daniel; Tarkalson, D.D.. |
| Alarm is expressed about the environmental impact of the increasing amount of reactive N in the atmosphere and in terrestrial and marine ecosystems around the globe. Much of this increase is attributed to production and use of N fertilizer. Use of fertilizer N is essential to meet growing global demand for agricultural commodities. Management is key to increasing productivity while also increasing N use efficiency and reducing N losses. A team of University of Nebraska-Lincoln scientists, with partial funding from the Nebraska State Legislature, addressed this challenge. They conducted 32 irrigated trials across diverse production conditions of Nebraska from 2002 to 2004 to evaluate corn response to rates of split-applied N. The results were reported in... |
| Tipo: Article |
Palavras-chave: Air Emissions; Chemistry; Fertilizer; Nitrogen; Soil. |
| Ano: 2011 |
URL: http://eprints.nwisrl.ars.usda.gov/1579/1/1535.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 N fertilizer on masses of NO3-N and NH4-N in leachate and soil were 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 urea... |
| Tipo: Article |
Palavras-chave: Amendments; Nitrogen; Soil. |
| Ano: 2011 |
URL: http://eprints.nwisrl.ars.usda.gov/1436/1/1403..pdf |
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| Registros recuperados: 425 | |
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