北京市森林碳储量及其动态变化

Forest carbon storage and its dynamics in Beijing

利用全国森林资源清查资料,依据建立的不同森林类型生物量和蓄积量之间的回归方程,估算了北京市不同时段的森林生物量和碳储量,并分析其动态变化特点。结果表明:北京市森林碳储量由1988年的532万t增加到2003年的852万t,平均每年以4.00%的速率递增,这说明北京市森林起着碳汇作用。全市森林总碳储量中,阔叶林碳储量的贡献最大,其中,栎类、杨树占主导地位;全市森林碳储量中幼、中龄林所占比重大,而且不同森林类型及不同龄级的碳密度均呈减少趋势。因此,在实施各重点造林工程的同时加强对现有森林的抚育和管理,将会使北京市森林碳汇能力进一步提高。

Using the national forest inventory data surveyed by the State Forestry Administration of P.R.China,forest carbon storage in Beijing was estimated with the regression equation between stand biomass and volume in different forest types.The results show that total forest carbon storage of Beijing increased from 5.32×106 t in 1988 to 8.52×106 t in 2003 with an amual increase of about 4.00%.This indicates that forest ecosystem in Beijing played a role as a carbon sink in that period.Broad-leaved forests,in which Quercus spp.and Populus spp.have played a dominant role,contributed much to the total forest carbon storage.The young forests and middle-aged forests accounted for a large proportion of total carbon in Beijing,and the carbon density of different forest types and different ages showed a decreasing trend.Therefore,Beijing forests would have a huge potential for carbon sink in the future if forests were fostered and managed well in major afforestation projects.