岩溶区免耕和翻耕措施对裸坡耕地产流产沙过程的影响

为揭示不同耕作措施对岩溶地区坡耕地产流产沙的影响,采用独立设计土槽、室内人工模拟降雨的方法,通过设定一定雨强下研究不同耕作措施对西南岩溶区裸坡耕地径流与土壤流失特征。结果表明:雨强为63mm/h,坡度小于10°时,翻耕措施能够加快地下孔隙的产流时间,而免耕能够滞缓其产流,翻耕的产沙量为免耕的66%;当坡度大于10°时,翻耕措施能够延缓地下孔隙的产流时间,而免耕则加速其产流,翻耕的产沙量分别为免耕的16%和6%。雨强为100mm/h,坡度小于10°时,随着坡度的增大,翻耕措施会加速地下孔隙流的汇流过程,免耕的产沙量是翻耕的41%;坡度大于10°时,翻耕措施能延缓地表径流的汇流过程,且翻耕的产沙量为免耕的68%和0.9%。同一坡度和雨强下,翻耕措施较免耕措施可减少土壤随径流流失。

Research on the Influence of No-till and Ploughing Measures on the Process of the Runoff and Sediment of Slope Farmland in Karst Region

In order to reveal the influences on the runoff producing and sediment on the hillslope which were exerted by different tillage measures in Karst region, the researchers used independent designed soil storehouse and indoor simulated rainfall measures, set particular rainfall intensity to study the features of runoff and the soil loss of the naked slope farmland in Karst region. The results showed: When the rainfall intensity was 63 mm/h and the declivity was less than 10°, ploughing measures could decrease the time of runoff producing of underground pores, and no-till could slow down its runoff producing, and its sediment yield was 66% of no-till. Otherwise, it conversed when the declivity was greater than 10°, and the sediment yield of ploughing were 16% and 6% of no-till separately. When the rainfall intensity was 100 mm/h and the declivity was less than 10°, the ploughing measures could speed up the confluence process of surface runoff on slopes, and the sediment yield of no-till was 41% of ploughing. Otherwise, it conversed when the declivity was greater than 10°, and the sediment yield of ploughing were 68% and 0.9% of no-till separately. In the circumstance of the same declivity and rainfall intensity, ploughing measures could decrease the loss of soil with surface runoff.