Response of runoff and sediment yield and nitrogen and phosphorus loss to soil and water conservation measures in orchards of red soil slope
The decline of land productivity and water pollution caused by the process of rainfall,runoff,erosion and nutrient output in orchard slope is one of the key problems restricting the economic development and ecological security in hilly areas of red soil.To clarify the quantitative effects of rainfall conditions and soil and water conser-vation measures on the characteristics of sediment yield and nitrogen and phosphorus loss,this study analyzed the quantitative effects of precipitation and rainfall intensity of different soil and water conservation measures on sedi-ment content and runoff coefficient,and then analyzed the quantitative relationship between sediment yield and ni-trogen and phosphorus loss concentration based on the observation data of orchards runoff plots from 2020 to 2022 in De'an County,Jiangxi Province.The results show that:(1)under different soil and water conservation measures,there are differences in the variation trends of sediment content and runoff coefficient with precipitation and rainfall intensity.Compared with clearing cultivation control(CK),the average sediment content of belt planting(S1),whole planting(S2),horizontal terrace(S3)and horizontal terrace with ladder wall planting(S4)decreased by 17.8％,42.3％,22.6％and 47.9％,respectively,and the average runoff coefficient decreased by 60％,71.8％,26.4％and 56.4％,respectively.Compared with engineering measures,vegetation measures could control runoff better,while engineering measures could intercept sediment better.(2)Under the conditions of S1,S2,S3,S4 andCK,STN/TN were 48.2％,45.6％,44.2％,45.9 and 45.7％,and STP/TP were 52.9％,50.0％,47.2％,45.2％and 47.4％,respectively,indicating that compared with the control conditions of different measures,the loss patterns of nitrogen and phosphorus did not change significantly.3)Compared with CK,the average concentra-tion changes of total nitrogen(TN)in S1,S2,S3 and S4 were-8.2％,-13.4％,15.0％and-12.1％,and the average concentration changes of soluble total nitrogen(STN)were-3.2％,-13.6％,11.4％and-11.7％,re-spectively.The average concentration of total phosphorus(TP)changed by-10.5％,-21.0％,39.5％,10.5％,and the average concentration of soluble total phosphorus(STP)changed by 0,-16.7％,38.9％,5.5％,respec-tively.Compared with engineering measures,vegetation measures played a more critical role in controlling nitrogen and phosphorus loss concentration.This study is of great significance for the rational arrangement of soil and water conservation measures on the slope of orchards in hilly areas of red soil.
precipitationrunoff and sediment yieldsoil and water conservationnitrogen and phosphorus lossorchard
国家科技期刊平台
NSTL
万方数据
