Li Rong, Liu Jiaxin, Zhang Mingda, Huang Congwu, Zhao Sihan, Zhang Meigen, Chen Liangfu
Hubei University, School of Resources and Environment, Wuhan, 430062, China; Hubei Key Laboratory of Regional Development and Environmental Response, Hubei University, Wuhan, 430062, China.
Hubei University, School of Resources and Environment, Wuhan, 430062, China.
Environ Pollut. 2025 Oct 1;382:126720. doi: 10.1016/j.envpol.2025.126720. Epub 2025 Jun 25.
Forest fire emission inventories constitute a fundamental data source for air quality modeling and investigations into the environmental impacts of forest fires. Current datasets predominantly offer daily or monthly emission estimates derived from Moderate Resolution Imaging Spectroradiometer (MODIS) fire products. However, detailed analyses of forest fire emission characteristics at the hourly resolution remain limited in China. In this study, we developed an hourly emission inventory for Chinese forest fires from 2016 to 2022 by integrating MODIS, Visible Infrared Imaging Radiometer Suite (VIIRS), and Himawari-8 active fire data, while incorporating diurnal variation patterns of forest fire activity. Utilizing this inventory, the spatial and temporal distributions of forest fire emissions across China were analyzed. The findings indicate that forest fires consumed approximately 95,495 Gg of dry matter during the study period, with the majority concentrated in the southern, southwestern, and northeastern forest regions, accounting for 44.3 %, 32.5 %, and 18.2 % of the total emissions, respectively. Emission hotspots in the southern forest region were predominantly located in provinces, such as Guangxi, Guangdong, Fujian, Jiangxi, and Hunan. In the southwestern forest region, hotspots were concentrated in southern Yunnan and Sichuan, while in the northeastern forest region, they were distributed across northeastern Inner Mongolia, northwestern Heilongjiang, and central Jilin and Liaoning. Months with higher forest fire emissions in China occur in February, March, April, October, November, and December. Significant seasonal differences exist in the diurnal variation of fire emissions across different forest regions. The Northeast Forest Region exhibits distinct emission peaks during spring and autumn, with peak times occurring at 13:00 and 12:00, respectively. The Southern and Southwest Forest Regions show similar diurnal variation characteristics. During winter, their peak emission times occur at 13:00-14:00 and 14:00-15:00, respectively. In spring and autumn, both regions display two emission troughs and three emission peaks. The occurrence times of these troughs and peaks in the Southwest Forest Region lag approximately 1 h behind those in the Southern Forest Region. These results provide critical insights into the spatiotemporal characteristics of forest fire emissions in China and offer a robust foundation for further research on the precise quantification of the air quality impacts associated with forest fires.
森林火灾排放清单是空气质量建模以及森林火灾环境影响调查的重要数据源。当前数据集主要提供源自中分辨率成像光谱仪（MODIS）火灾产品的每日或每月排放估算值。然而，在中国，针对森林火灾排放特征的每小时分辨率的详细分析仍然有限。在本研究中，我们通过整合MODIS、可见红外成像辐射仪套件（VIIRS）和 Himawari - 8 有源火灾数据，并纳入森林火灾活动的日变化模式，编制了2016年至2022年中国森林火灾的每小时排放清单。利用该清单，分析了中国森林火灾排放的时空分布。研究结果表明，在研究期间，森林火灾消耗了约95495Gg的干物质，其中大部分集中在南部、西南部和东北部森林地区，分别占总排放量的44.3%、32.5%和18.2%。南部森林地区的排放热点主要位于广西、广东、福建、江西和湖南等省份。在西南部森林地区，热点集中在云南南部和四川，而在东北部森林地区，它们分布在内蒙古东北部、黑龙江西北部以及吉林和辽宁中部。中国森林火灾排放较高的月份出现在2月、3月、4月、10月、11月和12月。不同森林地区火灾排放的日变化存在显著的季节差异。东北森林地区在春季和秋季呈现出明显的排放峰值，峰值时间分别出现在13:00和12:00。南部和西南部森林地区表现出相似的日变化特征。在冬季，它们的排放峰值时间分别出现在13:00 - 14:00和14:00 - 15:00。在春季和秋季，两个地区都显示出两个排放低谷和三个排放峰值。西南部森林地区这些低谷和峰值的出现时间比南部森林地区大约滞后1小时。这些结果为了解中国森林火灾排放的时空特征提供了关键见解，并为进一步研究森林火灾对空气质量影响的精确量化提供了坚实基础。
