基于GOSAT和OCO-2卫星的中国生物质燃烧CO2排放量估算研究

Vegetation fire and biomass burning release great amounts of the stored carbon from terrestrial ecosystem into the atmosphere, which has significant impact on global carbon cycle and atmospheric environment. Greenhouse gases observing satellite monitors the concentration of atmospheric carbon dioxide from space, and provides important information on the accurate spatial distribution of carbon dioxide. This study estimates the spatial and temporal characteristics of biomass burning emissions in China during 2001-2015 years based on the “Bottom-up” Method by using the terrestrial ecosystem model with fire emissions process and biomass burning emissions inventory model. With the help of remotely sensed data and open field experiment, we establish the database of available biomass, combustion factor and emission factor for all vegetation types (forest, grassland, shrubland and cropland). Meanwhile, we use the “Top-down” Method to retrieve the biomass burning emissions in China from 2001 to 2015 by using the atmospheric transport model and fire retrieval method based on the GOSAT and OCO-2 datasets. Finally, we compare and validate the biomass burning emissions estimated by the two methods and explore their consistencies in quantification the emissions of biomass burning. The biomass burning emission estimation by two different methods investigates the carbon loss in terrestrial ecosystem and carbon gain in atmospheric system. It will help us better understand the interactions among terrestrial ecosystem carbon cycle, biomass burning and atmospheric environment.

自然植被火灾通过生物量燃烧将陆地生态系统固定的碳重新释放到大气中，对全球碳循环和大气环境具有重要影响。温室气体观测卫星对全球大气二氧化碳浓度的高精度探测和监测，为准确把握大气二氧化碳浓度分布提供了重要依据。本研究基于“自下而上”型的陆地生态系统火灾碳排放过程模型，研究2001-2015年中国自然植被火灾碳排放的时空特征与变化趋势。结合遥感和野外调查实验，建立中国各典型火灾类型（森林火灾、草原火灾、灌木火灾和农田秸秆焚烧）可燃生物量，燃烧因子和排放因子数据库，耦合陆地生态系统模型，模拟各类型火灾碳排放量。同时采用“自上而下”型的大气输送模型和遥感反演模型，应用温室气体观测卫星GOSAT和OCO-2数据反演中国2001-2015年火灾碳排放量的时空特征。通过对“自下而上”和“自上而下”两种方法估算的火灾碳排放量进行比较和验证，揭示生态系统火灾碳排放-大气输送-大气二氧化碳浓度变化的作用机理。

生物质燃烧将陆地生态系统固定的碳重新释放到大气中，对全球碳循环和大气环境具有重要影响。温室气体观测卫星对全球大气二氧化碳浓度的高精度探测和监测，为准确把握大气二氧化碳浓度分布提供了重要依据。本研究基于“自下而上”型的陆地生态系统火灾碳排放过程模型，研究2001-2015年中国自然植被火灾碳排放的时空特征与变化趋势。结合遥感和野外调查实验，建立中国各典型火灾类型（森林火灾、草原火灾、灌木火灾和农田秸秆焚烧）可燃生物量，燃烧因子和排放因子数据库，耦合陆地生态系统模型，模拟各类型火灾碳排放量。同时采用“自上而下”型的大气输送模型和遥感反演模型，应用温室气体观测卫星GOSAT和OCO-2数据反演中国2001-2015年火灾碳排放量的时空特征。通过对“自下而上”和“自上而下”两种方法估算的火灾碳排放量进行比较和验证，揭示生态系统火灾碳排放-大气输送-大气二氧化碳浓度变化的作用机理。同时，应用本项目开发的模型估算了生物质燃烧大气PM2.5排放量，结合人口数据和暴露风险等级，首次建立了亚洲地区大气污染物暴露-环境健康影响评估模型，提出了大气污染控制情景下人体健康的潜在风险，为发展中国家制定最优化污染控制措施提供数据支撑和机理方案，为不同污染控制情境下大气污染物致死的减缓潜力和环境健康效应提供精准方案和策略。