中国森林生态系统的异戊二烯排放研究

植被的非甲烷碳氢化合物(non-methane hydrocarbon,NMHC)排放对大气环境变化有重要的影响,异戊二烯是对流层最主要的NMHC之一.本文应用Guenther的光温影响模型,对1993年中国森林生态系统的异戊二烯排放量进行了估算.结果发现:中国森林生态系统异戊二烯总的排放量约为0.03～8.6Tg/a,对全球碳的贡献量以碳计为0.026～7.589Tg/a,年最大可能排放量约占全球年排放总量的1.5%～4.3%;排放有较大的空间(地域)差异,年排放大值区分布在南方多林区和东北地区,以云南和黑龙江2省最大,对全国排放的贡献率分别为22%和11%;不同植被对总排放量的贡献率有较大差异,贡献率较大的杨树和栎类分别达到52.28%和44.29%.

Estimation of Isoprene Emission from Forest Ecosystems in China

Non-methane hydrocarbon (NMHC) emission from plants significantly affects the atmospheric environment change. Isoprene is the main NMHC in the troposphere. With the light-temperature model put forward by Guenther, isoprene emission from Chinese forest ecosystem was estimated. The result showed that the total isoprene emission was 0.03-8.6 Tg/a and release 0.026-7.589 TgC/a, which is 1.5%-4.3% of the global one. Isoprene emission has largely spatial variation, and the higher emissions occur in Southern and Northeast parts of China, where large forests are distributed. Yunnan and Heilongjiang are two higher emission provinces of China, and their contributions to the total are about 22% and 11%. The contribution varied with different species. The emissions from poplar and oak forests contribute 52.28% and 44.29% of the total, respectively.