The land area in a river network is divided into certain-scale square cells for the sake of precision, and, based on the physical mechanisms of rainfall-runoff processes and runoff pollution, the non-point source poll...The land area in a river network is divided into certain-scale square cells for the sake of precision, and, based on the physical mechanisms of rainfall-runoff processes and runoff pollution, the non-point source pollution from cells is estimated using the export coefficients of different land use types. The non-point source pollution from a land cell should all go into the closest fiver reach, so it is distributed according to the terrain of the plain river network area and the positions of land cells and river network reaches. A relationship between a single land cell and its pollution-receiving reach can be determined using this system. In view of the above, a spatial distribution model of the rainfall runoff and non-point source pollution in reaches of a plain river network area was established. This model can provide technological support for further research on the dynamic effects of non-point source pollution on water quality.展开更多
There is a great uncertainty in generation and formation of non-point source(NPS)pollutants,which leads to difficulties in the investigation of monitoring and control.However,accurate calculation of these pollutant lo...There is a great uncertainty in generation and formation of non-point source(NPS)pollutants,which leads to difficulties in the investigation of monitoring and control.However,accurate calculation of these pollutant loads is closely correlated to control NPS pollutants in agriculture.In addition,the relationships between pollutant load and human activity and physiographic factor remain elusive.In this study,a modified model with the whole process of agricultural NPS pollutant migration was established by introducing factors including rainfall driving,terrain impact,runoff index,leaching index and landscape intercept index for the load calculation.Partial least squares path modeling was applied to explore the interactions between these factors.The simulation results indicated that the average total nitrogen(TN)load intensity was 0.57 t km-2 and the average total phosphorus(TP)load intensity was 0.01 t km-2in Chengdu Plain.The critical effects identified in this study could provide useful guidance to NPS pollution control.These findings further our understanding of the NPS pollution control in agriculture and the formulation of sustainable preventive measures.展开更多
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment in China (Grant No. 2008X07101-005)
文摘The land area in a river network is divided into certain-scale square cells for the sake of precision, and, based on the physical mechanisms of rainfall-runoff processes and runoff pollution, the non-point source pollution from cells is estimated using the export coefficients of different land use types. The non-point source pollution from a land cell should all go into the closest fiver reach, so it is distributed according to the terrain of the plain river network area and the positions of land cells and river network reaches. A relationship between a single land cell and its pollution-receiving reach can be determined using this system. In view of the above, a spatial distribution model of the rainfall runoff and non-point source pollution in reaches of a plain river network area was established. This model can provide technological support for further research on the dynamic effects of non-point source pollution on water quality.
基金Key Research and Development Program of Hubei Province,No.2020BCA073Independent Innovation Research Program of Changjiang Institute of Survey,Planning,Design and Research Co.,Ltd.,No.CX2019Z05。
文摘There is a great uncertainty in generation and formation of non-point source(NPS)pollutants,which leads to difficulties in the investigation of monitoring and control.However,accurate calculation of these pollutant loads is closely correlated to control NPS pollutants in agriculture.In addition,the relationships between pollutant load and human activity and physiographic factor remain elusive.In this study,a modified model with the whole process of agricultural NPS pollutant migration was established by introducing factors including rainfall driving,terrain impact,runoff index,leaching index and landscape intercept index for the load calculation.Partial least squares path modeling was applied to explore the interactions between these factors.The simulation results indicated that the average total nitrogen(TN)load intensity was 0.57 t km-2 and the average total phosphorus(TP)load intensity was 0.01 t km-2in Chengdu Plain.The critical effects identified in this study could provide useful guidance to NPS pollution control.These findings further our understanding of the NPS pollution control in agriculture and the formulation of sustainable preventive measures.