降雨对川中丘陵区坡耕地土壤侵蚀和氮磷流失的影响  

Effects of Rainfall on Soil Erosion,Nitrogen and Phosphorus Loss from Sloping Cultivated Land in the Hilly Area of Central Sichuan

作　　者：李森[1] 田耘 罗雪梅[1] 罗海霞 罗勇[1] 涂卫国[1] LI Sen;TIAN Yun;LUO Xuemei;LUO Haixia;LUO Yong;TU Weiguo(Sichuan Provincial Academy of Natural Resource Sciences,Chengdu 610015,China;College of Environment and Civil Engineering,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]四川省自然资源科学研究院,四川成都610015 [2]成都理工大学环境与土木工程学院,四川成都610059

出　　处：《环境科学与技术》2024年第12期161-168,共8页Environmental Science & Technology

基　　金：四川省省级科研院所基本科研业务费项目(2024JDKY0001);四川省科技计划项目(2023YFS0365)。

摘　　要：为研究不同降雨强度对川中丘陵区坡耕地土壤侵蚀和氮磷流失的影响,该文采用人工模拟降雨试验,研究不同降雨强度(30、50、70和90 mm/h)和15°坡度条件下川中丘陵区坡耕地产流、产沙和氮磷流失特征。结果表明:随着降雨强度的增大,地表径流和壤中流的产流量与产沙量显著增加(P<0.05),产流量达到平衡的时间明显缩短,且在70 mm/h和90 mm/h的降雨强度下,地表径流达到平衡的时间最短(5 min)。产流结束时,70 mm/h和90 mm/h降雨强度下地表径流和壤中流的总氮、硝态氮、铵态氮含量均显著高于30 mm/h和50 mm/h(P<0.05);地表径流和壤中流的总磷和可溶性磷含量则呈现出随降雨强度增加而逐渐降低的趋势。相关性分析显示降雨强度与地表径流流量、地表径流产沙量、壤中流流量以及壤中流产沙量显著正相关(P<0.05),与氮磷含量呈显著负相关关系(P<0.05)。高强度降雨会加大川中丘陵区坡耕地土壤水力侵蚀和氮磷养分流失的风险,研究结果可为川中丘陵区坡耕地水土流失及农业面源污染防治提供基础数据。To study the effects of different rainfall intensities on soil erosion,nitrogen and phosphorus loss from sloping culti⁃vated land in the hilly area of central Sichuan,simulated rainfall was used to explore the characteristics of runoff and sediment yield,as well as the nitrogen and phosphorus loss characteristics in sloping cultivated land in the hilly area of central Sichuan under different rainfall intensities(30,50,70,and 90 mm/h)and 15°slope conditions.The results showed that with the in⁃crease of rainfall intensity,the discharge and sediment yield of surface runoff and soil flow increased significantly(P<0.05),and the time to reach the equilibrium was significantly shortened(P<0.05),and the time to reach the equilibrium of surface runoff was the shortest(5 min)when the rainfall intensity was 70 and 90 mm/h.At the end of runoff generation period,the contents of total nitrogen,nitrate nitrogen and ammonium nitrogen in surface runoff and soil flow under rainfall intensities of 70 and 90 mm/h were significantly higher than those of 30 and 50 mm/h(P<0.05).The contents of total phosphorus and soluble phosphorus in surface runoff and soil midstream showed a decreasing trend with the increase of rainfall intensity.Correlation analysis showed that rainfall intensity was positively correlated with surface runoff,surface runoff yield,soil runoff and sediment yield,and negatively correlated with nitrogen and phosphorus content(P<0.05).The high intensity rainfall will increase the risk of soil hydraulic erosion and nitrogen and phosphorus nutrient loss in sloping cultivated land in the hilly areas of central Sichuan,and the results can provide basic data for the prevention and control of soil erosion and agricultural non-point source pollution in sloping cultivated land in the hilly areas of central Sichuan.

关 键 词：降雨强度 径流 氮磷流失 坡耕地 川中丘陵区 

分 类 号：X14[环境科学与工程—环境科学] S157.1[农业科学—土壤学]