东北寒区积雪-融雪时空变异及其对流域非点源污染的影响

Northeast China is cold and rich in snow. The spring snowmelt runoff has obvious effected on the nonpoint source of the watershed, which causes serious nonpoint source pollution to the river in spring flood period. The reduction of snow and the premature snowmelt caused by global warming are the most critical problems affecting the quantity and quality of surface water resources. However, there is few research on the change of snowmelt and its effect on the nonpoint source pollution of the watershed in the snowmelt period. The key problem is the difficulty in obtaining the characteristic parameters of snow cover and snowmelt. This project plans to select the source area of Liao River, a typical cold area in Northeast China, as research area, and extract relevant parameters and variables to the greatest extent based on the cloud removal sliding synthetic remote sensing data. A water quantity-quality coupling model will be built by integrating the SRM snowmelt runoff model and the SWAT snowmelt module based on the modified degree-day factor algorithm considering the solar radiation, and the effect of snowmelt on the nonpoint source pollution will be quantified. The change of snow cover and snowmelt, and its impact on nonpoint source pollution under the climate change in the future will be forecasted by combining the atmospheric circulation model and the statistical downscaling method. Research results will provide new technique and method for the nonpoint source pollution simulation under the background of climate change in cold area, and provide scientific evidence for the effective pollution control and remediation in the source area of Liao River during spring snowmelt period.

东北寒区气候寒冷且积雪丰富，春季融雪径流对流域非点源冲刷效应明显，导致河流春汛期非点源污染严重。全球气候变暖引起东北地区降雪减少以及融雪时间提前，是影响地表水资源数量和质量最重要的问题。目前针对积雪融雪变化及其对流域融雪期非点源污染影响方面的研究并不多见，其中难点和关键问题在于积雪、融雪特征参数难以获取。本项目选取我国东北典型寒区—辽河源头区作为研究区，基于去云处理的滑动多日合成遥感数据，最大限度提取相关参数和变量指标，明确流域积雪融雪时空演变规律；基于考虑太阳辐射的修正度日因子算法，构建SRM融雪径流与SWAT融雪模块集成的水量-水质耦合模型，定量分析积雪融化对流域非点源污染的影响；结合大气环流模型和统计降尺度方法，预测未来气候变化情景下流域积雪、融雪变化以及非点源污染响应特征。研究成果为气候变化背景下寒区非点源污染模拟预测提供新的技术和方法，为辽河源头区春汛期河流污染的有效控制和治理提供科学依据。

东北寒区气候寒冷且积雪丰富，春季融雪径流对流域非点源冲刷效应明显，导致河流春汛期非点源污染严重。全球气候变暖引起东北地区降雪减少以及融雪时间提前，是影响地表水资源数量和质量最重要的问题。目前针对积雪融雪变化及其对流域融雪期非点源污染影响方面的研究并不多见，其中难点和关键问题在于积雪、融雪特征参数难以获取。本项目选取我国东北典型寒区—辽河源头区作为研究区，基于去云处理的滑动多日合成遥感数据，最大限度提取相关参数和变量指标，明确流域积雪融雪时空演变规律；基于考虑太阳辐射的修正度日因子算法，构建SRM融雪径流与SWAT融雪模块集成的水量-水质耦合模型，定量分析积雪融化对流域非点源污染的影响；结合大气环流模型和统计降尺度方法，预测未来气候变化情景下流域积雪、融雪变化以及非点源污染响应特征。研究成果为气候变化背景下寒区非点源污染模拟预测提供新的技术和方法，为辽河源头区春汛期河流污染的有效控制和治理提供科学依据。