社会经济发展对三峡澎溪河流域氮磷负荷的影响

为了研究社会经济发展对三峡库区澎溪河流域氮和磷负荷过程的影响,基于GIS技术和分布式非点源模型-SWAT,依据2004,2008年和2013年《重庆市统计年鉴》中农村人口数、GDP及城镇化率等社会经济数据,结合流域土地利用演变情况,通过改进SWAT模型管理措施功能,模拟分析了该流域氮和磷负荷过程变化规律。结果表明:径流量、总氮和总磷误差决定系数均在0.6以上,模拟结果可靠;农村地区总氮、总磷年际浓度平均降低了60.6%和50.2%,负荷呈减少趋势;城镇地区总氮、总磷年际浓度平均增加了34.3%和4.4%,负荷呈增加趋势。总氮和总磷负荷变化的原因是大量农村人口进入城市,耕地面积减少;工业发展和城镇化建设加快,城区人口密度增加,城市垃圾增多等。研究成果可以为三峡库区水环境保护和管理提供科学依据。

Study on effect of socio-economic development on N and P load variation in Pengxi river basin in Three Gorges Reservoir area

To study the impact of socio-economic development on N and P load variation in Pengxi river basin in the Three Gorges reservoir area, by using GIS technology and the distributed non-point source SWAT model and based on the data of land-use change，rural population, GDP, urbanization rate in Chongqing statistical yearbooks in 2004,2008 and 2013, the effect rule of N and P load variation process was analyzed by the improved management measure function module of the model. The results show that the simulation results are reliable, thecoefficient R?of flow, nitrogen and phosphorus are all greater than 0.6. Annual average concentration of nitrogen and phosphorus reduced by 60.6% and 50.2%, the load significantly decreased in rural areas while annual concentration of nitrogen and phosphorus increased by 34.3% and 4.4% in urban area, the load also increased in urban areas. The variation causes are rural population entering city to work, arable land gradually decreasing, urban population density increasing, urban garbage increasing, speedy development of industry and urbanization. The study can provide scientific basis for protection and management of water environment in Three Gorges Area.