Effects Of Nonpoint Source (NPS) Pollutant Load On Water And Research On Quantified Approaches

Based on the National Natural Science Foundation Program, the Produce of Non-point Source(NPS) Pollutant Load and the Influence of the Background Parameters of Soil (49973029) and the relative research work and production projects recently, this paper made systematic studies on the transportation and transformation principles of phosphorous and nitrogen from agricultural NFS in soil and receiving water, quantitative approaches for agricultural and urban NFS pollutant load assessment, and the effects of NFS pollutant load on surface and groundwater. And the corresponding quantitative methods were presented. Models developed in this paper are: agricultural NFS pollutant loading model in river plain area, urban NFS pollutant loading model; one-dimension surface water receiving model, one-dimension groundwater receiving model on vertical penetration, and one prediction model for nutrient loss with the influence of background parameters of soil. The details are as following:1. The influences of background parameters of soil on the loss of nutrient in soilRecently, the Artificial Neural Network (ANN) has been used excessively in complex systems because of its advantages in nonlinear equating. This approach was first used in analysis and determination of background parameters affecting the loss of nutrient factor in soil and the potential loss of nutrient from soil.2. Quantitative approaches for NFS pollutant loading assessment(1) Pollutant loading model for urban runoff was developed. Simulation models for sedimentation of NFS in dry season, NFS from storm runoff process, and discharge process of NFS from sewer were established with respect to urban land use, accumulation rate of NFS pollutant loading from streets, and sedimentation of pollutant load during dry season in storm drain. And different formulae might be applied in different NFS.(2) Pollutant loading model for agricultural runoff was developed. The basic theories of runoff producing and confluence were used in spatial and temporal distribution of rural NFS pollutant load for the first time, considering characteristics of runoff pollutant load occurring in various land uses. Calibration was completed using experimental data and receiving water models. The results showed that the applied method might improve the prediction accuracy of water quality model.3. The effects of NFS pollutant load on surface water and groundwater(1) Water quality modeling program (WASPS) was applied successfully to simulate and predict pollutant constituents of nutrient sources in river plain. Using one-dimension water net work quantity model, coupled with one part (water quality modeling) of water quality simulating model, and combining water quality simulating model with pollutant loading model can make it more easy and accessible to simulate water quality. Thus, this program was improved.(2) One-dimension groundwater quality model on vertical penetration with the influence of NFS pollutant load was developed. Based on the primary theories of mass transportation in porous media, the related formulae were derived. And this model was calibrated using the measured data.