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The effect of cattle grazing on soil physical and chemical properties in a silvopastoral system in the Peruvian Amazon 总被引:2,自引:0,他引:2
In a six-year-old peach palm (Bactris gasipaes) plantation, centrosema (Centrosema macrocarpum), a leguminous forage plant,
was established as a cover crop which was eventually grazed. This experiment was designed to monitor probable changes in soil
physical and chemical properties and measure peach palm fruit production and live-weight gain of cattle grazing this silvopastoral
system. The experiment was installed on land that was previously cleared by a D7 bulldozer having a straight blade that mixed
the thin layer of topsoil with the acid subsoil (20–40 cm) and severely compacted the soil. The results demonstrated that
the centrosema cover crop reduced soil bulk density, increased water infiltration rates and reduced mechanical resistance.
In general soil physical properties were improved with the use of Centrosema as forage and cover crop. Soil acidity and aluminum
saturation decreased considerably, while potassium concentrations increased. Calcium and magnesium concentrations decreased
over time as these minerals were stored in the pasture biomass, translocated to fresh peach palm fruits and/or exported to
animals. A strong competition for nutrients was observed between the peach palm plants and Centrosema. The low production
of peach palm fruits was in response to mechanized land clearing during initial establishment of the plantation, and also
probably due to deficits of N, P, K, Ca and Mg in the soil instead of being a consequence to the presence of cattle. The average
increase in live-weight gains of the cattle was at a rate of 445 g/animal/day during the four-years of the study. Such an
increase is substantially greater than those registered in the area under traditional grazing systems used in the region.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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主要探讨了杨-粮间作新栽培模式对小麦产量和质量的影响。研究结果表明:5年生杨树杨-粮间作新栽培模式[(3×3)m×20m,(3×3)m×30m,(3×3)m×40m]小麦产量低于对照农田10%~15%、;林内小麦种子的淀粉含量和蛋白质含量均高于对照农田,分别增加了12%和22.1%,蛋白质提高幅度大于淀粉提高幅度。影响小麦产量和千粒重的主要因子为照度、空气温度、空气湿度及土壤含水量;提高小麦质量的主要因子为空气温度。 相似文献
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核桃丰产的栽培是通过土肥水管理、整形修剪、病虫害防治等管理技术措施,提高核桃优质产量,进一步改变礼县贫穷山区的落后面貌,不断增加农民经济收入。 相似文献
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