小尺度林分碳密度与碳储量研究

在数字化长潭自然保护区地图的基础上,均匀设置66个标准样地进行群落调查,根据调查数据进行双向指示种分析(Two-way indicator species analysis,TWINSPAN).结果表明:保护区内主要包括常绿阔叶林、杉木林、针阔混交林、以及杉木-马尾松共优针叶林4种群落类型;每种类型按树种组分别计算其蓄积量、生物量和碳储量,并与面积加权后得出该群落的碳密度(单位面积碳储量);4种群落碳密度依次为33.94、34.70、51.00和42.05t.hm-2;长潭自然保护区碳储量总计为2.265×105 t,平均碳密度为44.77 t.hm-2,远大于广东省乔木林平均碳密度(25.47 t.hm-2).相关分析表明,碳密度主要受树高、胸径和群落演替时间的影响,与海拔、坡度等地形因子和林木密度没有明显的相关关系(P>0.05).

Small-Scale Estimation of Carbon Density and Carbon Storage of Forest Stands

Sixty-six sample plots were evenly laid out in Changtan Nature Reserve using a digitized topographic map for pant inventory. Two-way indicator species analysis (TWINSPAN) of the sample data categorized the vegetation of the nature reserve into 4 community types, i.e., evergreen broad-leaved forest (EB), Cunninghamia lanceolata forest (CL), coniferous and broad-leaved mixed forest (CB), and coniferous forest dominated by C. lanceolata and Pinus massoniana(CP). Stand volume, biomass, and carbon storage were first calculated by tree species group, and then weighted for area to obtain carbon density of a certain community type. Carbon density for each of the 4 community types, i.e., EB, CL, CB, and CP, was 33.94, 34.70, 51.00 and 42.05 t·hm^-2, respectively. The forest vegetation in the nature reserve had a total carbon storage of 2.265×10⁵t, and an average carbon density of 44.77 t·hm^-2, much greater than the average value of Guangdong. Correlation analysis indicated that the major determinants for carbon density were tree height, diameter at breast height (DBH), and succession time of communities, while slope, elevation and stand density had no significant relations with carbon density.