| Weihe is the largest tributary of the the Yellow River River in Shanxi, Weihe, Shanxi province received a large number of industrial wastewater and domestic sewage, and with the rapid development of society and e conomy in Guanzhong area, the urban expansion and the increase of population, the Weihe River water environment is serious damage to the extreme deterioration of the water quality of Weihe, Shaanxi issued a series of comprehensive control of water pollution governance policy, such as "Shaanxi province Weihe all remediation planning and implementation plan", "Shaanxi province Weihe basin water pollution prevention action plan for three years" （2012-2014）, non-point source pollution based on the SWAT model to simulate the flow field distribution in Weihe, detailed analysis of non-point source pollution in time and space, and inspection the effectiveness of water pollution control scheme, and the prediction of non-point source pollution in Weihe in the future, and provide theoretical guidance for the corresponding department of water pollution in Weihe section of Shaanxi Academic basis. The main research content is as follows:（1） This research collection of Weihe basin in Shanxi province of spatial data and attribute data,Spatial databas（DEM, land use map, soil type map） projection coordinates of WGS1984UTMZone49N, attribute data including weather, hydrology and water quality data were used for model calibration and verification. Generates a digital river, the basin is divided into 35, and land use, soil type and grade of overlay, the basin is divided into 634 hydrological response units.（2）The parameter sensitivity analysis was carried out on the model, get the greatest influence on the model of the eight parameters to adjust, the simulated data and the measured data rate and verify the final result between the measured analog better fitting degree, reflected the SWAT model suit with Shanxi section of Weihe river is better, and can be applied to Shanxi section of Weihe river.（3） To analyze spatial and temporal variations of non-point source pollution, in the time distribution of pollutants, the output of pollutants are mainly in flood season and the highest rainfall month, thus controlling non-point source pollution is the most important period in flood season, this rule: to meet the rising of agricultural non-point source pollution, non-point source pollution is associated with rainfall runoff. In the basin of the spatial distribution of agricultural non-point source pollution, rainfall, land use types and soil utilization types of nonpoint source pollution effect step by step, pollution mainly concentrated in Tongguan, Xi ’an, Xianyang, and found a yellow spongy soils is influence of sediment and the type of soil nitrogen and phosphorus pollution is larger, and slope of non-point source pollution has a certain influence.（4） The effect of comprehensive treatment of Weihe comprehensive inspection: before and after loading different land use map operation model and SWAT fertilization changes before and after the treatment of water pollution in Weihe compared to non point source output, found that non-point source pollution is significantly reduced, and compared the water quality changes before and after the comprehensive treatment, all achieved good effect of comprehensive control Weihe.（5） To predict the future of non-point source pollution: a combination of "the overall planning of land use in Shanxi province" （2006-2020）, by modifying the land use map of Weihe basin to continue converting cropland to grass, non-point source pollution operation simulation model in 2020 found that if to continue the execution of the program, the non-point source pollution will Weihe continued to reduce a lot, and the prediction of future climate change and output of non-point sources found in the future climate change, rising temperatures, precipitation increased under the influence of if we do not take measures of total nitrogen and total phosphorus production has been in a rising state. |
PDF Full Text Request