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通过野外模拟降雨试验,研究玉米种植下紫色土坡耕地地表糙度的变化特征,并分析地表糙度对产流产沙的影响。结果表明:随生育时期的推进,地表糙度逐渐衰退,在抽雄期时达到最小,地表糙度平均变幅大小为横坡垄作>顺坡垄作>平作,苗期时变化幅度最小,拔节期或抽雄期时最大;玉米长势越好地表产流时间越晚,各生育时期地表产流时间均为顺坡垄作最早,横坡垄作最晚;全生育期内地表径流量呈现先降低后增高的变化趋势,除苗期外横坡垄作产流量均低于平作,总体而言地表糙度对地表径流的影响未达到显著水平;苗期时土壤侵蚀量随地表糙度的增大呈指数递减,而其余3个生长时期均是随地表糙度的增大土壤侵蚀量呈指数或者幂函数递增。
Field simulated rainfall experiments were conducted to study the variation of surface roughness of purple soil sloping cultivated land under maize planting. The effects of surface roughness on runoff and sediment yield were analyzed. The results showed that with the promotion of the growth period, the surface roughness gradually declined and reached its minimum at the tasseling stage. The mean amplitude of the surface roughness varied from ridged slope> ridged slope> flattened ridge, with the smallest change in seedling stage, The peak of maize growth was the later. The time of surface runoff in each growth period was the earliest along the slope and the last was the runoff. The surface runoff showed the first decrease and then the increase in the whole growth period In addition, the runoff of lateral ridges except for seedling stage was lower than that of flat cropping. Overall, the effect of surface roughness on surface runoff did not reach a significant level. Soil erosion amount decreased exponentially with the increase of surface roughness at seedling stage The other three growing periods are both increasing exponentially or increasing exponentially with soil surface roughness.