森林生物量是研究森林生态系统中能量流动与物质循环的基础参数,森林碳汇分析对努力争取2060年前实现碳中和具有指导意义。采用四川省4次森林资源连续清查数据,系统比较单木模型法与扩展因子法对生物量和碳储量估算的差异,建立19种主要乔木林类型的固碳速率模型,分析其碳汇潜力及碳储量密度分布变化规律。结果表明:单木模型法与扩展因子法的生物量和碳储量估算结果无统计学差异,森林植被生物量和碳储量密度差异主要源于乔木林类型估算结果的差异;各主要乔木林类型固碳速率模型拟合决定系数均大于0.7,杨树林、桦木林、阔叶混交林、其它软阔类林分和其它硬阔类林分幼龄时期碳储量增长迅速,针阔混交林、冷杉林、油松林、柏木林、针叶混交林、云杉林等成熟时期固碳潜力较大;2002—2017年,四川省森林植被生物量和碳储量密度逐渐增大,呈现由低密度向高密度转移的趋势。

Forest biomass is the basic information for studying energy flow and material cycle in forest ecosystem.Forest carbon sink analysis is of significance to achieve carbon neutrality before 2060.Based on the data of four continuous forest inventories in Sichuan Province,this paper systematically compared the differences in biomass and carbon storage estimation between the single-tree model summation method and the expansion factor method,established the carbon sequestration rate models of 19 major arboreal stands,and analyzed its carbon sequestration potential and distribution of carbon storage density.The results showed that there was no statistical difference in biomass and carbon storage estimation between the single-tree model summation method and the expansion factor method.The differences in biomass and carbon storage density of forest vegetation mainly came from the estimation differences of arbor stands.The fitting determination coefficients of carbon sequestration rate models of major arbor stands were all greater than 0.7.The carbon sequestration potential of poplar stand,birch stand,broad-leaved mixed stand,softwood broad-leaved stand,and hardwood broad-leaved stand increased rapidly during young age.The carbon sequestration potential of the coniferous and broad-leaved mixed stand,fir stand,Chinese pine stand,cypress stand,coniferous mixed stand,and spruce stand was greater during mature age.The forest vegetation biomass and carbon storage density increased gradually in Sichuan from 2002 to 2017,showing a trend of transfer from low density to high density.