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保护耕作制控制水土流失的研究在南部山区水土保持中心已有五十多年的历史.随机抽样调查分析了当前季节性降雨自然灾害的变化和世界土壤流失通用方程的侵蚀指数,在某种意义上说明了保护耕作主要是这些典型季节.同时也证明了这个地区季节降雨最大概率在六月上旬到九月上旬之间.而最大侵蚀指数在六月中旬到八月末之间.在美国这些概率分布与热带湿润气候是一致的.在2.71公里的流域内,四种耕作试验的径流土壤流失的测定已进行十二年多了,这个流域是典型的山地土壤,坡度范围为2%～7%.这四种试验包括没有冬季作物覆盖的大豆保护耕作法和三种不同的全部用冬季作物覆盖的大豆、谷物和高粱保护耕作法.
Conservation farming system to control soil and water loss research in the Southern Mountain Soil and Water Conservation Center has a history of more than 50 years.Statistical random sampling survey analysis of the current seasonal rainfall natural disasters change and erosion index of the world soil erosion general equation in a sense It shows that conservation tillage is mainly for these typical seasons, and also shows that the maximum seasonal rains in this area are between the first half of June and the first half of September, while the maximum erosion index is between mid-June and the end of August. In the United States, these probabilities Distribution and tropical humid climate is consistent in 2.71 km of the basin, the four tillage tests runoff soil loss determination has been carried out more than twelve years, the basin is a typical mountain soil, the slope of the range of 2% to 7% The four trials included a soybean conservation tillage without winter crop cover and three different tillage protection practices with soybeans, grain and sorghum all covered with winter crops.