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除灌溉之外,无机肥料对培育的放牧地的生产能力有很大影响。建立多年生牧草,首先是禾本科及其同豆科混播牧草的适宜水分状况,能够利用高额的无机肥料,其中也包括氮肥。苏联的科学研究机关,对各种不同土壤—气候条件,根据草层成分、草层利用特点,拟定了适宜的氮、磷、钾施肥量。但是在实践中经常很难测定最大有效氮肥量。问题在于,列入提高氮量,在高氮量未减少之前的各种方案的田间试验中,其产量增长曲线呈抛物线。换言之,在集约经营的农业中,产量随着施肥量的增长,开始时完全相符地的增加,然后产量的增长就减少。产量付给肥料单位的报酬相应的减少。
In addition to irrigation, inorganic fertilizers have a significant impact on the productivity of grazing lands. The establishment of perennial grasses, first of all, is the appropriate water regime for gramineous and mixed legumes with the same legumes, enabling the use of high levels of inorganic fertilizers, including nitrogenous fertilizers. The scientific research institutions of the Soviet Union have formulated suitable nitrogen, phosphorus and potassium fertilizers for various soil-climatic conditions according to the characteristics of grass layer composition and grass layer utilization. However, it is often difficult to determine the maximum effective nitrogen fertilizer in practice. The problem is that the yield growth curve is parabolic in the field trials that include various options for increasing nitrogen until various high nitrogen levels are not reduced. In other words, in intensively managed agriculture, the output increased exactly in line with the increase in the amount of fertilizer applied, and then the increase in output decreased. The amount of compensation paid to fertilizer units is correspondingly reduced.