石灰岩地不同作物坡面土壤侵蚀和养分流失的影响

Effect of Different Crops in the Limestone Area on the Slope Soil Erosion and Nutrient Loss

通过室内人工模拟降雨试验,研究不同作物种类下石灰岩坡地土壤侵蚀和养分流失的特征。结果表明：CK、花生和红薯坡面之间的产沙量、产流量、养分流失量均差异显著,红薯坡面在产沙量、产沙模数、产流时间中为三者最小,而花生坡面在节流方面表现突出;花生与红薯在养分固持方面均优于CK,但红薯坡面各养分固持效果优于花生坡面13.8%-300%;花生和红薯坡面的氮素和磷素流失拟合方程结果表现出显著相关性,拟合系数超过0.85,建立三项式函数为特征方程更适合描述花生与红薯种植坡面养分迁移过程。

The simulating rainfall method was adopted to study the characteristics of soil erosion and nutrient loss in the limestone under the different crops. The sediment yield, runoff yield and nutrient loss amount a-mong CK, peanut and sweet potato had significant difference. The sweet potato slope had the minimal sediment yield, sediment yield modulus and runoff-yielding time, while the peanut slope had prominent rainfall retaining function, the peanut and sweet potato were superior than CK concerning the nutrient immobilization. However, the sweet potato＇s immobilization effect was 13.8%-300% better than peanut slope. The N and P loss fitting equation results of peanut and sweet potato slopes showed significant correlation with the fitting coefficient over 0.85. The trinomial function was established as the characteristic equation to better describe the nutrient transfer process of peanut and sweet potato slopes.