从气候地带性和地理区域分布两方面对森林生态系统碳储量及固碳能力,以及土地利用变化对森林固碳的影响和森林固碳估算不确定性的原因进行综述.据估算,全球森林生态系统碳储量为652~927 Pg C,固碳能力达到4.02 Pg C · a~(-1).各气候地带森林碳储量表现为热带最大(471 Pg C),寒带次之(272 Pg C),温带(113~159 Pg C)最小,固碳能力表现为热带(1.02?1.3 Pg C ·a~(-1))最大,温带次之(0.8 Pg C · a~(-1)),寒带(0.5 Pg C · a~(-1))最小;各地理区域森林碳储量表现为南美洲(187.7?290 Pg C)最大,其次是欧洲(162.6 Pg C)、北美洲(106.7 Pg C)、非洲(98.2 Pg C)和亚洲(74.5 Pg C),而大洋洲(21.7 Pg C)最小,固碳能力为南美洲热带(1276 Tg C ? a~(-1))和非洲热带(753 Tg C ? a~(-1))较大,其次是北美洲(248 Tg C ? a~(-1))和欧洲(239 Tg C ? a~(-1)),而东亚(98.8?136.5 Tg C ? a~(-1))较小.为进一步减少森林生态系统固碳估算的不确定性,今后应综合运用连续长期观测技术、样地清查、遥感分析和模型模拟等方法.
英文摘要:
As a dominant part of terrestrial ecosystems,forest ecosystem plays an important role in absorbing atmospheric CO_2 and global climate change mitigation. From the aspects of zonal climate and geographical distribution,the present carbon stocks and carbon sequestration capacity of forest ecosystem were comprehensively examined based on the review of the latest literatures. The influences of land use change on forest carbon sequestration were analyzed, and factors that leading to the uncertainty of carbon sequestration assessment in forest ecosystem were also discussed. It was estimated that the current forest carbon stock was in the range of 652 to 927 Pg C and the carbon sequestration capacity was approximately 4.02 Pg C · a~(-1). In terms of zonal climate, the carbon stock and carbon sequestration capacity of tropical forest were the maximum, about 471 Pg C and 1.02-1.3 Pg C · a~(-1) respectively; then the carbon stock of boreal forest was about 272 Pg C, while its carbon sequestration capacity was the minimum, approximately 0.5 Pg C · a ~(-1) ; for temperate forest, the carbon stock was minimal, around 113 to 159 Pg C and its carbon sequestration capacity was 0.8 Pg C ? a~(-1). From the aspect of geographical distribution, the carbon stock of forest ecosystem in South America was the largest (187.7-290 Pg C),then followed by European (162.6 Pg C),North America (106.7 Pg C), Africa (98.2 Pg C) and Asia (74.5 Pg C), and Oceania (21.7 Pg C). In addition, carbon sequestration capacity of regional forest ecosystem was summed up as listed below : Tropical South America forest was the maximum (1276 Tg C ? a~(-1)),then were Tropical Africa (753 Tg C ? a~(-1)), North America (248 Tg C ? a~(-1)) and European (239 Tg C ? a~(-1)), and East Asia (98.8-136.5 Tg C ? a~(-1)) was minimum. To further reduce the uncertainty in the estimations of the carbon stock and carbon sequestration capacity of forest ecosystem, comprehensive application of long-term observation, inventories, remote sensing and modeling method should be required.