基于GIS和LUR模型的西安市PM2.5浓度空间分布模拟研究

基于地理信息系统GIS和土地利用回归LUR模型,模拟西安市PM2.5浓度空间动态分布,结果表明:与PM2.5浓度相关性最高的分别为缓冲区为2 km的水域面积、人口密度和距离水域距离,R 2分别为0.501,0.393和0.280;与PM2.5浓度相关性最低的分别为缓冲区为4 km的水域面积、未利用地面积和耕地面积,R 2分别为0.039、0.021和0.017.未考虑风速建立的LUR模型多元回归的相关系数为0.856,R 2为0.733,考虑风速的相关系数为0.892,R 2为0.796,表明风速对于污染物的分布影响较大,LUR模型模拟效果较好.模拟的PM2.5年均浓度高风险区分布于中部,中风险区分布于中西部,低风险区分布于东南部和西部.

Simulation Study on Spatial Distribution of PM2.5 Concentration in Xi`an based on GIS and LUR Model

The dynamic distribution of PM2.5 concentration in Xi'an city was simulated by using GIS and LUR model,.The results showed that, the highest correlation with PM2.5 concentration were water body area within a buffer zone of 2 km, population density and distance to waters, and R 2 were 0.501, 0.393 and 0.280, respectively.In contrast, the lowest correlation with PM2.5 concentration were water body area, unused land area and arable land area within a buffer zone of 4 km, and R 2 were 0.039, 0.021 and 0.017, respectively, Correlation coefficient of multiple regression was 0.856 without considering the wind speed for established LUR, R 2 was 0.733, the correlation coefficient was 0.892 considering wind speed, R 2 was 0.796, showed that the wind speed has a great influence on the distribution of pollutants, simulation effect of LUR model was better.The high risk areas of simulated annual average concentration of PM2.5 distributed in the central, medium risk zones located in the central and western regions, and low risk areas distributed in the southeast and the west.