School of Resource and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China; Department of Geography and Resource Management, The Chinese University of Hong Kong, Hong Kong.
Department of Geography and Resource Management, The Chinese University of Hong Kong, Hong Kong.
Sci Total Environ. 2019 Feb 25;653:23-35. doi: 10.1016/j.scitotenv.2018.10.307. Epub 2018 Oct 24.
With China's rapid economic growth, particle pollution, especially fine particulate matter (PM), which is known to have adverse health impacts, has become an increasingly serious issue. Satellite aerosol optical depth (AOD), an important physical property of aerosol particles, can serve as a proxy for investigating particle pollution because it can provide observations with comprehensive spatial and temporal coverage compared with ground-level measurements. This study used an improved 14-year high-resolution AOD dataset to examine the spatial characteristics and temporal dynamics of the dominant pollutants in China from 2003 to 2016 using advanced statistical methods. The improved AOD dataset combines the Moderate Resolution Imaging Spectroradiometer (MODIS) 3-km dark target AOD and 10-km deep blue AOD datasets, which enables a comparison of aerosol loading between eastern and western China. Pixel-based analysis indicates a significant difference between eastern and western China: high AOD values were generally observed in the east with a notable decrease, while low aerosol loadings were found in western China with no distinct change. The most particle polluted areas were the North China Plain, Hubei-Hunan region, Sichuan Basin, and Guangxi-Guangdong region in eastern China and western Qinghai and Tarim Basin in western China, with changes in the national AOD average center shifting to the northwest from 2013 to 2016. The impact factor analysis based on geographically weighted regression indicates that the effect of topography on the spatial characteristics of AOD is negative and more important in eastern China, which has low elevations. Built-up areas significantly exacerbate air pollution in the areas between eastern and western China, and there is no apparent AOD-vegetation relation dominates the country. This study thus provides a comprehensive understanding of the spatiotemporal variations of particle concentrations and can facilitate environmental management, policies to alleviate particle pollution, and health risk assessment studies.
随着中国经济的快速增长，颗粒物污染，尤其是细颗粒物（PM），已经成为一个日益严重的问题。卫星气溶胶光学厚度（AOD）是气溶胶粒子的一个重要物理性质，可以作为研究颗粒物污染的替代物，因为它可以提供比地面测量更全面的时空覆盖观测。本研究使用改进后的 14 年高分辨率 AOD 数据集，结合先进的统计方法，研究了 2003 年至 2016 年中国主要污染物的空间特征和时间动态。改进后的 AOD 数据集结合了中分辨率成像光谱仪（MODIS）3 公里暗目标 AOD 和 10 公里深蓝 AOD 数据集，这使得可以比较中国东部和西部的气溶胶负荷。基于像素的分析表明，中国东部和西部之间存在显著差异：东部地区的 AOD 值通常较高，且呈明显下降趋势，而西部地区的气溶胶负荷较低，没有明显变化。污染最严重的地区是中国东部的华北平原、湖北-湖南地区、四川盆地和广西-广东地区，以及中国西部的青海和塔里木盆地，全国 AOD 平均值中心从 2013 年到 2016 年向西北方向转移。基于地理加权回归的影响因子分析表明，地形对 AOD 空间特征的影响是负面的，在中国东部海拔较低的地区更为重要。建成区显著加剧了中国东部和西部之间地区的空气污染，且 AOD 与植被之间没有明显的关系。因此，本研究提供了对颗粒物浓度时空变化的全面认识，有助于环境管理、缓解颗粒物污染的政策制定和健康风险评估研究。
