Study On The Output Charactersistic Of Non-point Source Phosphorus In Shaying River Basin Of Fu Yang On SWAT Model

The Shaying River is the largest tributary of the Huaihe River.The water quality of the Shaying River is of great significance to the utilization of water resources and agricultural development in the basin.In this study,geographic information technology,mathematical statistics and hydrological model simulation were used to study the non-point source phosphorus pollution output characteristics of the Shaying River Basin in Fuyang City,and to explore the migration and transformation of non-point source phosphorus pollutants in the basin.The general soil loss equation identifies the degree of soil erosion in the Shaying River Basin of Fuyang City from a macroscopic scale,establishes the non-point source phosphorus loss coefficient,and identifies the key source areas of non-point source phosphorus loss in the study area.The main results were showed as follows:（1）Establish the SWAT model of the study area,and determine and verify the SWAT model results based on the 2011-2016 runoff and water quality data of the Fuyang Gate.There is a good agreement between the simulated and measured values of runoff and total phosphorus during the periodicity and verification period,.The R² of the regular runoff is0.85,the E_ns is 0.82,and the R² of the runoff during the verification period is 0.82,and the E_ns is 0.79.The rate of R² is 0.64 and the Ens is 0.61.The R² of the total phosphorus in the verification period is 0.64 and the E_ns is 0.62.The results of runoff and total phosphorus are verified.The SWAT model is compared in the Shaying River Basin of Fuyang City.Good applicability.（2）The loss of organic phosphorus,the loss of mineral phosphorus,soluble phosphorus and total phosphorus loss in 2011-2016 were 0.76⁴.19 kg/ha,1.2⁵.88kg/ha,0.34².08 kg/ha and 2.30¹2.15kg/ha respectively.In terms of time distribution,the loss of organic phosphorus,soluble phosphorus,mineral phosphorus and total phosphorus showed an increasing trend;in the spatial distribution,the loss of organic phosphorus,soluble phosphorus,mineral phosphorus and total phosphorus in the study area showed a loss in the southern region.The degree is much greater than the trend in the northern region.（3）The soil erosion erosion modulus under the township administrative unit in the study area is from 291 to 3568 t/（km²·a）,and the multi-year average soil erosion modulus is 1593 t/（km²·a）.The whole study area is mildly eroded.The soil of the administrative unit of Chengguan Township is in moderate erosion state,and the annual soil erosion amount is 2815t/km².When the slope band is from 3°to 6°,the maximum erosion modulus growth rate of the soil is 50%,which is the sensitive slope zone under soil erosion in the study area.Landuse is moderately eroded in rural settlements,and land use is mildly eroded by towns,woodlands,drylands,and other land uses.（4）Try to establish the non-point source phosphorus loss coefficient in the study area.The results show that the total phosphorus loss coefficient of the Shaying River Basin in Fuyang City is from 0 to 0.67,and the average loss coefficient of total phosphorus in the whole area is 0.11.The main towns and rural residential areas in the high-loss areas are The loss factor of the study area is generally higher in the south than in the north.The total phosphorus loss coefficient under the towns administrative unit is from 0.01 to 0.27,and the rainfall and total phosphorus loss coefficient have the same trend.Rainfall is an important factor affecting the total phosphorus loss coefficient.Suji town,Chengguan Town,Wangji Town,Zhongshi Street and Sanhe Town are the key source areas for total phosphorus loss in the study area.It is recommended to set up animal and bird ban areas in the key source areas of total phosphorus loss,plant ecological vegetation,prevent soil erosion,and control non-point source phosphorus pollution.Figure[74]Table[15]Reference[126].