云南省天然林碳储量和碳密度动态变化探析

Analysis on the Changing Tendency of Carbon Sequestration and Carbon Density of Natural Forests in Yunnan Province

基于八次(1977-2018年)全国森林资源清查数据,采用生物量转换因子法分析云南省天然林碳储量和碳密度。结果显示:1)云南省天然林碳储量从第二次全国森林资源清查的45 088.60万t增长到第九次清查的81 015.10万t,净增35 926.50万t,年均增长率1.64%;2)天然林碳密度整体呈“升-降-升”态势,第九次全国森林资源清查估算的碳密度值为55.79t/hm^(2);3)第七次至第九次全国森林资源清查中,中龄林碳储总量和增量均为最大,三次清查中,天然林碳密度关系均为过熟林>成熟林>近熟林>中龄林>幼龄林,按林种分析,碳储量排序均为防护林>用材林>特用林>薪炭林,碳密度均为特用林>防护林>用材林>薪炭林;4)不同优势树种中,栎类、阔叶混、云南松、针阔混、其他软阔类、冷杉碳汇贡献最大,不同优势树种碳储量增量排序为阔叶混>针阔混>云南松>针叶混>冷杉,铁杉、冷杉、云杉碳密度估算值较大,生长质量良好。

Based on the forest resources inventory data of eight times(1977-2018),the biomass expansion factor was used to analyze the carbon sequestration and carbon density of natural forests in Yunnan Province.The results showed that: 1)The carbon sequestration of natural forests in Yunnan Province increased from 450.886 million tons in the second inventory to 810.151 million tons in the ninth inventory, with a net increase of 359.265 million tons and an annual growth rate of 1.64%;2)The carbon density of natural forest showed a "rising-falling-rising" trend, carbon density tested in the ninth inventory was 55.79 t/hm^(2);3)In the seventh to ninth inventory, the total amount and increment of carbon sequestration in middle-age forest were the highest, and the order of carbon density in natural forest in the third inventory was overmature forest>mature forest>near mature forest>middle-age forest>young forest, the order of carbon sequestration of different forest species was shelterbelt forest>timber forest>special forest>fuel forest, and the order of carbon density was special forest>shelterbelt forest>timber forest>fuel forest;4)Among the different dominant tree species, Quercus,broadleaves mixed forest, Pinus yunnanensis,mixed coniferous and deciduous forests, other soft wood and Abies fabri were the main contributors to the carbon sequestration of natural forests in Yunnan Province, the order of carbon sequestration increment of different dominant tree species was: broadleaves mixed forest>mixed coniferous and deciduous forests>Pinus yunnanensis>mixed coniferous>Abies fabri,and the estimated carbon density of Tsuga chinensis, Abies fabri,Picea asperata was quite high, with sound growth quality.