重庆市主城区冬季PM2.5空间分布模拟

Simulation of PM_(2.5) spatial distribution in winter in the main urban area of Chongqing

PM_(2.5)以其对环境空气质量及人类健康的巨大威胁而逐渐引起了专家学者的关注。以西南地区典型山地城市——重庆市主城区为研究区,利用多元线性回归方法和地理信息系统(GIS)技术,基于2013—2017年冬季(1、2、12月)原重庆市环境保护局发布的17个空气环境监测站点实测数据,同时考虑自然及社会经济因素,构建了基于多因素的多元回归模型,模拟了重庆市主城区2013—2017年冬季PM_(2.5)平均浓度的空间分布状况。结果表明:PM_(2.5)浓度受多因素的影响,其中缓冲半径1 500m内建设用地面积、1 000m内林地面积、2 500m内产业点密度、1 500m内道路长度及高程影响较大;通过多因素与PM_(2.5)浓度的相关性建立的回归模型,能有效模拟PM_(2.5)浓度的空间分布特点,重庆市主城区冬季PM_(2.5)平均浓度的空间分布呈现中西部高、北部和东南部较低的格局;2013—2017年冬季PM_(2.5)平均浓度有下降的趋势,2015年冬季下降幅度尤为明显。此研究结果对探讨PM_(2.5)浓度的空间分布特点有一定的应用价值,可为减轻空气PM_(2.5)污染及提高城市空气质量提供重要的科学依据。

The attention of experts and scholars gradually was paid to PM2.5for its tremendous threat to environmental air quality and human health.Based on the real measured data of17air environment monitoring stations released by Chongqing Environmental Protection Bureau in the winter of2013-2017(January,February and December),the main urban area of Chongqing was taken as the research area to simulate the spatial distribution of PM2.5average concentration in the main urban area of Chongqing during the winter of2013-2017by utilizing multiple linear regression methods and GIS technology,considering both natural and socioeconomic factors and constructing a multiple regression model on the basis of multiple factors.Results were illustrated as follows,the mass concentration of PM2.5was affected by multiple factors and outstanding factors could be concluded,including the area of construction land within1500m buffer zone,the area of forestland within1000m buffer zone,the density of the industrial point within2500m buffer zone,the length of the road within1500m buffer zone and the elevation.The spatial distribution characteristics of PM2.5concentration could be simulated effectively from the regression model established by the correlation between multiple factors and PM2.5concentration.A pattern from the spatial distribution of PM2.5average concentration in winter in the main urban area of Chongqing was presented that the midwest was high,the north and southeast were lower.There was downside of the average concentration of PM2.5in the winter of2013-2017,especially in the winter of2015.The study results have certain application value to explore the spatial distribution characteristics of PM2.5concentration and provide significant scientific basis for reducing PM2.5pollution and improving urban air quality.