摘要: Cattle grazing, defecation and urination rates, growth, mortality were studied on pasture formed from rain forest in the Amazon territory of Venezuela. consumed 12-16 percent total aboveground plant productivity two sites. The nutrients this vegetation recycled to soil dung (N, P, Ca, Mg) urine (N K). Nutrients cattle excreta more available plants spatially concentrated than litterfall. stocking rates sites 0.43-0.89 animal units/ha, ranged 21 42 kg live wt/ha/yr. Nonharvested was 20 per year, there no successful reproduction. low growth reproductive failure, part may result phosphorus concentration grass.
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