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耕地土壤的侵蚀受作物残茬覆盖土地表面比例的影响。在实行水土保持耕作法的若干州内,如果在一块田地上作物残茬覆盖面积的百分数超过规定的最小值时,可得到分摊费用资金。我们采取了一种仅用残茬覆盖度而不考虑以前耕作方法或残茬量的办法,预测连续条播作物中水土保持耕作制下的土壤侵蚀。因此,量测作物残茬的方法必须以合理的量测次数提供一块地上平均残茬覆盖的估算。
Erosion of arable land is affected by the proportion of surface area covered by crop stubble. In a number of states implementing soil and water conservation farming practices, cost-sharing funds are available if the percentage of crop stubble coverage in a field exceeds a specified minimum. We have adopted a method that uses only stubble coverage regardless of past tillage methods or stubble amounts to predict soil erosion under continuous cropping with soil and water conservation practices. Therefore, the method of measuring crop stubs must provide an estimate of the average above-ground stubble coverage at a reasonable number of measurements.