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Crop production in Georgia and the Southeastern U.S. can be limited by water. Highly-weathered, drought-prone soils are susceptible to runoff and erosion. Rainfall patterns generate runoff producing storms followed by extended periods of drought during the crop growing season. Thus, supplemental irrigation is often needed to sustain profitable crop production. Increased water retention and soil conservation would efficiently improve water use and reduce irrigation amounts/costs and sedimentation, and sustain productive farm land, thus improving producer's profit margin. Soil amendments, such as flue gas desulfurization (FGD) gypsum, have been shown to retain rainfall and/or irrigation water through increased infiltration while decreasing runoff (R) and sediment (E). Objectives were to quantify rainfall partitioning and sediment delivery improvements with surface applied FGD gypsum from an Ultisol managed to conventional till (CT) and to assess the feasibility of using FGD gypsum on agricultural land in southern Georgia. A field study (Faceville loamy sand, Typic Kandiudult) was established (2006, 2007) near Dawson, GA managed to CT, irrigated cotton (Gossypium hirsutum L.). FGD gypsum application rates evaluated were 0, 1.1, 2.2, 4.5, and 9 Mg ha− 1. Gypsum treatments and simulated rainfall (50 mm h− 1 for 1 h) were applied to 2-m wide × 3-m long field plots (n = 3). Runoff and E were measured from each 6-m2 plot (slope = 1%). FGD gypsum plots averaged 26% more infiltration (INF), 40% less R, 58% less E, 27% lower maximum R rates (Rmax), and 2 times lower maximum E rates (Emax) than control plots. Values of INF and water for crop use increased, and R, E, Rmax, and Emax decreased as FGD gypsum application rate increased. Values of INF, R, E, Rmax, and Emax for 9 Mg ha− 1 plots were as much as 17% greater, 35% less, 1.9 times less, 35% less, and 1.9 times less than those from other FGD gypsum plots, respectively; and 40% greater, 40% less, 2.2 times less, 52% less, and 2.9 times less than those from control plots, respectively. Applying FGD gypsum to agricultural lands is a cost-effective management practice for producers in Georgia that beneficially impacts natural resource conservation, producer profit margins, and environmental quality. Agriculture in the Southeast provides a viable market for the electric power industry to convert disposal costs of FGD gypsum into a profitable commodity. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(15):1789-1796
In the Red River Valley, about 385,000 Mg of lime is used to help refine about 39,000 Mg of sugar beets. In a greenhouse study, sugar-beet-processing lime (spent lime; SL), commercial ag lime (AL), and reagent-grade lime (RL) were added to an acidic soil at rates of 0, 1.96, 3.93, and 7.86 Mg ECC ha?1. Wheat was planted, and aboveground biomass and root masses were determined after 44 d of growth. Soil pH increased the greatest with the highest lime application rates. Incorporation of lime uniformly increased soil pH in the pots, whereas with surface application, soil pH decreased with increasing depth. The SL yielded more aboveground soil biomass and root mass than the AL and RL. Use of SL for increasing soil pH and reducing exchangeable Al in acid soils would be a viable use for this industrial by-product. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(14):1736-1750
Substrates have been increasingly used in recent years for carnation crops. Burnt rice husk (BRH) is widely available and used as a substrate in Colombia. The present work aims to compare the effects of two aqueous extraction methods on the chemical contents. Saturated and 1:1 (v/v) extractions were performed in three replications. Ionic forms of the macronutrients (NO3?, NH4+, PO4H2?, K+, Ca2+, Mg2+, and SO42?, in meq L?1), micronutrients (Fe, Mn, Zn, Cu, and B, in mg L?1), Cl?, CO3 H? in meq L?1, electrical conductivity in dS m?1, and pH were analyzed. Except for NH4+, Cl?, and B the determination coefficient R2 was greater than 95 percent. Average values and standard errors of data have been used to define suitable intervals for 1:1 extractions. Proposed intervals for 1:1 extracts are consistent with the saturated extract and therefore are a good tool to optimize the management of fertigation in those crops. 相似文献
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为了开发TMR饲料的原料资源,对10余种副产品的化学成分、重金属含量及In situ DM消失率进行了研究,结果表明：酒精粕、麦芽皮、柑橘渣可作为能量饲料;木炭、咖啡粕、灵芝粕可作为粗纤维饲料,芝麻粕可作为蛋白质饲料,而啤酒糟可以成为反刍动物良好的蛋白质和粗纤维来源。同时所有测定的副产品的Cr、Hg、Pb和Cd等重金属的含量都在安全范围之内。另外,饲料在瘤胃内的分解常数“a”值以木炭和酒精粕最高,咖啡粕、麦芽皮及芝麻粕等次之,而灵芝粕和啤酒糟最低。“b”值以羽扇豆皮和啤酒糟最高,其次是酒精粕、麦芽皮和芝麻粕,木炭最低。ED值以酒精粕最高,其次是麦芽皮、木炭、羽扇豆皮及咖啡粕,而灵芝粕最低。 相似文献
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For molecular biological detection of Mycobacterium avium subsp. paratuberculosis (MAP), PCR methods with primers targeting different regions specific for MAP are used worldwide. However, some uncertainties exist concerning the specificity of certain target regions and the sensitivity. To identify the methods which are best suited for diagnostics, 8 single-round and 5 nested PCR systems including 12 different primer pairs based on IS900 (9 x), ISMav2 (1x), f57 (1x), and locus 255 (1x) sequences were compared regarding their analytical sensitivity and specificity under similar PCR conditions. Reference strains and field isolates of 17 Mycobacterium species and subspecies, 16 different non-mycobacterial bovine pathogens and commensals were included in this study. Single-round PCR resulted in a detection limit of 100 fg to 1 pg, and nested PCR in 10 fg or below. Depending on the specific primer sequences targeting IS900, false positive results occurred with one of the five single-round and two of the four nested PCR systems. This also applied to the single-round PCR based on ISMav2 and the nested PCR based on f57. A high number of non-specific products were primarily detected for the single-round PCR assay based on ISMav2, but also for a single-round PCR targeting the IS900 and the locus 255. In conclusion, stringent selection of IS900-specific primers ensures that IS900 remains a favourite target sequence for amplification of MAP specific loci. The studied PCR systems based on f57, and locus 255 can also be recommended. Revision of ISMav2 primers is necessary. Single-round PCR systems are very reliable. Nested PCR assays were occasionally disturbed by contaminations, thus bearing a risk for routine diagnostics. 相似文献
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ABSTRACT High-quality by-products from fish processing are sometimes discarded unless fishmeal plants are located nearby. Other preservation methods, such as acidification, are less commonly used to inhibit spoilage. In this study, individual salmon by-products (heads, viscera, and a mixture) were stabilized through fermentation by lactic acid bacteria and through ensilage by direct acidification. Lipid and protein quality decreased in all samples with storage time (up to 120 days). Of note, viscera and heads preserved separately consistently maintained a lower, more effective pH than when mixed together, regardless of treatment, which has major implications for how fish processing waste should be collected and stored if maximum nutritional quality is to be preserved. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(1):33-46
White mustard and soybean seed meals were compared for weed control and yield of organically grown broccoli and spinach. The meals were incorporated into the soil 2 weeks before crop planting at two rates (1.24 and 4.48 t ha?1). Weed densities and hand-weeding time were recorded twice during the growing seasons and weed biomass was measured at crop harvest. Compared to the 1.24 t ha?1 soybean treatment, weed densities were 52 to 95% and 41 to 45% less at 3 and 6 weeks after planting, respectively, in both crops with the 4.48 t ha?1 white mustard seed meal treatment. Time required for hand weeding at these times was also reduced by up to 82% and 48%, respectively. Broccoli yield was similar in all the treatments, but spinach yield was greatest in the 4.48 t ha?1 treatments for both seed meals. Petiole nitrate and nutrient concentrations in both crops were generally similar in all the treatments. 相似文献
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Angela R. Possinger José A. Amador 《Communications in Soil Science and Plant Analysis》2016,47(1):121-135
The practice of applying seaweed to agricultural fields may provide plant nutrients and improve soil quality in coastal agroecosystems, but little is known about its effects on soil properties or crop production. We conducted a preliminary evaluation of changes in soil biological and chemical properties and sweet corn (Zea mays L.) production using seaweed as a partial source of nitrogen (N) (40–55%) for one growing season, using a preformulated organic fertilizer treatment for comparison. Soil electrical conductivity, potassium (K+), sulfate (SO42-), and active carbon (C) increased with seaweed addition relative to the organic fertilizer, whereas potentially mineralizable N and pH decreased, with effects varying over time. Sweet corn yield and quality were either equivalent to that with the organic fertilizer or improved. The short-term positive (e.g., increased active C) and negative (e.g., increased salt levels) effects on soil quality suggest further evaluation of this practice is justified. 相似文献