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第一讲坡地梯田化坡地梯田化是保持水土、发展生产的重要措施之一。它的作用在于通过梯田、地埂、软埝、水簸箕等田间工程,有计划地改变原来的地形,使陡坡变为缓坡,使缓坡变为平地,截短径流线,减缓径流速度,制止冲刷,保持水土,增加生产。根据黄河中游各试验站进行试验所取得的资料和在群众中调查的结果,梯田在一般情况下可以增产一至三倍,每亩可拦蓄地表径流18—50立方米;地埂一般可增产20—60%,每亩可拦蓄泥沙5—13立方米。从这些数据里,我们可
Lecture 1 slope terraced slope terraced is to maintain soil and water, one of the important measures to develop production. Its role is to change the original terrain planically by field works such as terraces, terraces, soft booms and water dustpan, to change the steep slope into a gentle slope, to change the gentle slope into a flat ground, to shorten the runoff line, to slow down the runoff speed, and to stop the erosion , To maintain soil and water, increase production. According to the data obtained from experiments conducted at various pilot stations in the middle reaches of the Yellow River and the survey results among the masses, the terraces can increase the yield by one to three times under normal circumstances and can save 18-50 cubic meters of surface runoff per acre; 60%, sediment per mu can hold 5-13 cubic meters of sediment. From these data, we can