2000—2015年中国PM_(2.5)浓度时空分布特征及其城乡差异

Spatio-temporal distribution characteristic of PM_(2.5) concentration and the difference of PM_(2.5) concentration between urban areas and rural areas in China from 2000 to 2015

近40年来,中国快速经济发展引发较为严重的大气污染,PM_(2.5)是一种重要的空气污染物,掌握其时空分布规律是对其进行防治的重要前提。基于遥感反演出的PM_(2.5)浓度数据集,研究了中国2000—2015年PM_(2.5)浓度的时空分布特征,并基于界定的1376个城镇城区及对应乡村的边界分析了每年PM_(2.5)浓度值的城乡差异,用线性趋势分析法计算城镇PM_(2.5)浓度的年际变化速率及显著性。结果表明,研究期内,PM_(2.5)浓度高于35μg/m^3的面积比例由18.58%增加至32.03%,低于15μg/m^3的面积从43.92%减少到25.12%。PM_(2.5)污染最严重的地区分布在塔里木盆地、河北南部、河南北部和山东西部。从2000年到2015年,中国绝大多数城镇PM_(2.5)浓度显著增加,尤其是在东北平原、太行山以东的河北省西南部、燕山以南的北京天津及河北唐山、鲁中南山地丘陵及周围平原地区、华北平原江苏省北部。PM_(2.5)城乡差异在河北省、山西省两条东北-西南向S形条带区域、浙江省-福建省条带及天山北部绿洲区域较大。研究对PM_(2.5)高浓度区域、PM_(2.5)浓度增长较快区域以及城区PM_(2.5)浓度对乡村影响较大区域进行图示,为中国进一步控制雾霾污染提供一定科学依据。

The rapid economic development has caused serious air pollution in the past 40 years.PM2.5 is one of main air pollutants,examination of its spatial and temporal distribution is an important prerequisite for its prevention and control.Based on remote-derived PM2.5 concentration date set,this study explored the spatio-temporal distribution characteristic of PM2.5 concentration in China from 2000 to 2015,and analyzed the annual difference of PM2.5 concentration between urban areas and corresponding rural areas of 1376 towns according to their boundary.Furthermore,we calculated the rate and significance of interannual variation of PM2.5 concentration for each town using linear trend analysis method.The results showed that the proportion of area with PM2.5 concentration higher than 35μg/m3 increased from 18.58%to 32.03%,and lower than 15μg/m3 decreased from 43.92%to 25.12%during the study period.The most severely polluted areas were located in Tarim Basin,south of Hebei Province,north of Henan Province,and west of Shandong Province.In addition,PM2.5 concentration increased significantly in most towns in China from 2000 to 2015,especially in the Northeast Plain,southwest of Hebei Province located to the east of Taihang Mountain,Beijing,Tianjin,Tangshan located to the south of Yanshan Mountain,Mountains and Hills in central and south of Shandong Province and the surrounding Plains,and north of Jiangsu Province in North China Plain.The difference of PM2.5 concentration between urban areas and rural areas is large in two northeast-southwest S-shaped belts in Hebei and Shanxi Province,Zhejiang-Fujian Province belt,and oasis area located to the north of Tianshan Mountain.In this study,we identified the area with high PM2.5 concentration,high rate of increase of PM2.5 concentration,and intense effect of urban areas on surrounding rural areas,providing some scientific basis to further control the haze pollution in China.