中文摘要：

本文基于2014—2015年中国190个大中城市PM2.5的监测数据，建立空间数据统计模型，总结两年内PM2.5的浓度、空间集聚的年际变化和存在问题，为相关研究与决策提供参考。结果显示：①2015年较2014年全国平均PM2.5浓度下降10％，达标天数提升了4.4％，空气质量整体改善，但改善的天数主要集中在春夏秋季，冬季改善幅度甚微，其中12月污染加重。②2015年PM2.5整体污染范围缩小，污染核心区由京津冀向鲁西北和豫北地区扩散，京津冀、长三角、长江中游等城市群年均浓度降幅较大，长三角、珠三角和成渝城市群日均达标率增长较快。③2015年PM2.5的集聚性更明显，浓度高值区范围减小，热点地区更密集地分布在以京津冀地区为中心的华北地区，并呈多中心格局。由此，应该加快构建制度支持的多中心监督治理模式，以华北地区为先行先试区域，构建管理支持的多区域联动治理模式，培养环境伦理支持的公众环保意识，实现民防民治。

英文摘要：

Based on PM2.5 concentration observation data for 2014 and 2015 from 190 medium and large cities in China we look at changes in PM2.5 concentration and trends in spatial agglomeration. We found that in 2015, the average PM2.5 concentrations in China decreased by 10% compared with 2014, the number of days of compliance enhanced by 4.4% , and the air quality improved obviously. Spring improved the most, followed by summer, autumn and winter. In December 2015, the pollution was worse than the same period in 2014. The other months were improved, with the largest decrease in June （21.48%） , and a decline of less than 10% in February, August and September. In 2015, the pollution area of PM2.5 was less than that in 2014, and the pollution core area spread from Beijing, Tianjin and Hebei to the northwest and north of Henan. The areas where there were large declines in PM2.5 annual average concentration were mainly in the Beijing-Tianjin- Hebei Region, Yangtze River Delta, middle reaches and other urban agglomerations; cities with rapid growth in the average daily standard days were mainly concentrated in the Yangtze River Delta, Pearl River Delta and Chengyu urban agglomerations. In contrast to PM2.5 in 2014, the concentration of PM2.5 was more obvious in 2015, the concentration of high-value areas decreased, and the hot spots were more densely distributed in the North China Region centered around the Beijing-Tianjin-Hebei Region. Hot agglomeration regions showed a multi-center cluster phenomenon. Based on the above situation, it is necessary to speed up the construction of institution-supported multi-center supervision and governance mode. In the North China Region we should build a management-supported multi-regional linkage governance mode, construct public environmental consciousness governance supported by environmental ethics, and incorporate these into the Chinese cultural rejuvenation system.