Impact of straw burning on air quality in China: An empirical analysis based on Landsat-8 moderate resolution satellite monitoring data
利用Landsat-8卫星数据提高秸秆焚烧活动检测精度，通过双向固定效应模型发现秸秆焚烧显著增加PM2.5等污染物浓度，秋季和上风区域影响更明显，且过火面积是关键因素。
The open-air burning of straw has been one of the major sources of air pollution in China. Accurately detecting and measuring the scope and extent of straw-burning activities is crucial for effective environmental policies. However, the wide-spread practice by numerous small-scale rural units across rural China makes this a challenging undertaking. Our study contributes to this stream of research by leveraging mid-resolution Landsat-8 OLI sensor data to improve the accuracy of straw-burning activity detection. More importantly, we also investigate the role of seasonal variations, geographic location, and fire area in assessing environmental effects of straw burning. Using a two-way fixed-effects regression model, the results show that straw burning significantly increases concentrations of key air pollutants, with PM 2.5 being the most affected. Each detected fire hotspot results in an increase in PM 2.5 concentration of approximately 0.14-0.30 μg/m 3 , equivalent to about 0.31%-0.66% of the mean level. The effect is particularly pronounced in the autumn and upwind regions, where each additional fire hotspot raises PM 2.5 levels by around 0.88 μg/m 3 , equivalent to approximately 1.94% of the mean level. Moreover, the size of the burned area is critical for evaluating the environmental impact of straw burning, a factor often overlooked in previous research. These findings provide a comprehensive understanding of straw burning's effects on air quality in China, offering valuable insights for developing countries and contributing essential scientific evidence for policy development and implementation. • Mid-resolution Landsat-8 OLI sensor data is used to improve the accuracy of straw burning activity detection. • Considered the role of seasonal variations, geographic location, and fire area in assessing environmental effects of straw burning. • Straw burning significantly increases concentrations of key air pollutants, with PM 2.5 being the most affected. • The effect is particularly pronounced in the autumn and in upwind regions. • The size of the burned area is critical for evaluating the environmental impact of straw burning.