玉米生长期坡耕地地表径流及侵蚀产沙特征

为了弄清玉米生长过程中侵蚀动态变化，该文采用人工模拟降雨与微小区相结合的方法，研究了紫色土区不同耕作措施对坡耕地地表径流及侵蚀产沙的影响。结果表明:在雨强1.0 mm/min条件下，平作坡面在种植前径流量最小，横坡垄作坡面在拔节期—抽雄期坡面径流量最小。在雨强1.5 mm/min条件下，横坡垄作坡面在玉米拔节期—抽雄期径流量最小。在雨强2.0 mm/min条件下，横坡垄作坡面在玉米苗期—拔节期坡面径流量最小。在雨强为1 mm/min和1.5 mm/min条件下，不同耕作措施坡面在玉米的抽雄期—成熟期产流时间最短，在雨强为2.0 mm/min条件下，不同耕作措施坡面在苗期—拔节期产流时间最短。这一研究成果可为区域水土流失有效防治提供理论依据。

Surface Runoff and Sediment Yield Characteristics of Sloping Cropland during Maize Growth Season

In order to clarify the process of erosion dynamic change at the different growth stages of maize, the simulated rainfall experiments and runoff plot experiment were employed to investigate characteristics of surface runoff and sediment yield among different tillage practices (flat planting, longitudinal ridge and cross ridge) during the period of corn maturity. The results showed the runoff amount was the minimum for the conventional tillage before planting and for the ridge tillage in the jointing stage—heading stage of maize under the condition of rainfall intensity 1.0 mm/min. The runoff amount was the minimum for the ridge tillage in the jointing stage—heading stage of maize under the condition of rainfall intensity of 1.5 mm/min. Under the condition of rainfall intensity of 2.0 mm/min, the runoff amount was the minimum for the ridge tillage at the seedling—jointing stage of maize. Under the condition of rainfall intensity of 1.0 and 1.5 mm/min, the runoff generation time was the shortest at the tasseling—maturity stage of maize for all tillage practices. However, the runoff generation time was the shortest at seedling—jointing stage under rainfall intensity of 2.0 mm/min. This study provides a certain theoretical basis for the effective prevention and control of soil erosion.