Characterization of phosphorus pollution output and best management practices in the Fengle River basin
This study used water quantity and water quality data to calibrate and verify the runoff and total phosphorus(TP)parameters of the SWAT model to better control non-point source phosphorus pollution in the Fengle River basin.It modeled the spatiotemporal distribution characteristics of TP loads in the basin from 2011 to 2021 and analyzed the reduction effects of best management practices(BMPs)on TP output.The results showed that temporally,the basin's annual average TP output was 77.58 tons,with the highest TP output(141.65 tons)in 2020,which was 4.3 times that of 2019.TP output was concentrated primarily during the flood season from May to October,accounting for 70.1% of the annual output.Sub-basins with a high proportion of farmland had high TP load intensities,with spatial variations closely related to land use.The correlation coefficients for TP load between farmland and forest land during the flood season and non-flood season are 0.924 7 and 0.419 3,respectively.Reduced fertilization,filter strips,and grassed waterways were effective in reducing TP output.The filter strip had the greatest TP reduction effect among individual BMPs.Comprehensive management practices had the greatest TP reduction in the basin,with annual reduction rates ranging from 43.41% to 61.23% .The output of phosphorus pollution in Fengle River basin is jointly affected by precipitation characteristics and land use,and the output of phosphorus can be effectively reduced by reducing fertilization,establishing vegetation filter strips or grassed waterways,and the results provide a theoretical basis and methodology for the relevant regions to control the source of emission reduction.
total phosphorusspatiotemporal distributionSWAT modelbest management practicesFengle River basin
国家科技期刊平台
NSTL
万方数据
