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我国干旱、半干旱地区劳动人民用洪用沙历史悠久。但多系利用缓坡地形,短距离输引达到目的。现代灌溉工程问世以来,多数灌区特别是大型灌区,一般都是按照输送清水的理论规划设计渠道系统。为防止泥沙入渠,陕西规定河源来水含沙量超过15%即关闸停引。因而在伏旱期间,正当关中、陕北灌区农作物需水的关键时刻不能正常引水灌溉,严重影响农作物的生长。为解决这一实际问题,自1976
China’s arid and semi-arid areas of working people flood with sand has a long history. However, the use of gentle slope terrain, short-range transmission to achieve the purpose. Since the advent of modern irrigation projects, most irrigation districts, especially large-scale irrigation areas, have generally designed the drainage system according to the theoretical plan of transporting clean water. In order to prevent sediment into the ditch, Shaanxi stipulates that the sediment concentration of more than 15% of the water from the source is closed at the gate. Therefore, during the drought period, at the critical juncture of Guanzhong and Northern Shaanxi irrigated areas, irrigation at the critical moment of crop water demand can not be normal, seriously affecting crop growth. To solve this practical problem, since 1976