大兴安岭地区南北部幼中龄林碳储量研究

Carbon storage of young and middle age forest in south and north Daxing'anling mountains

为了解大兴安岭林区南部和北部落叶松与白桦幼中龄林碳密度差异,准确估算该地区碳储量,本文结合南北部两个典型林业局抚育伐样地调查及森林资源统计资料,分析了南北部落叶松和白桦幼中龄林林分特征及生物量差异,利用生物量转换因子连续函数法建立了生物量(B)与蓄积量(V)的线性关系。结果显示,南部落叶松和南北部白桦直径分布均为右偏山状曲线,北部落叶松为左偏山状。样地生物量密度分布近似于正态曲线,南部各样地之间分布相对均匀,北部各样地分布相差较大。落叶松和白桦生物量与蓄积量线性关系分别为B=0.6726*V+0.5592和B=0.7317*V-0.2932。南部地区落叶松和白桦幼中龄林碳密度分别为30.54 t·hm-2和30.06 t·hm-2,北部地区分别为24.19 t·hm-2和26.77 t·hm-2。整个内蒙古大兴安岭地区落叶松和白桦幼中龄林碳储量分别为8 546.4万t和2 798.9万t,碳密度分别为26.08 t·hm-2和25.01 t·hm-2。由于幼中龄林具有较高的碳增长潜力,合理地经营大兴安岭地区落叶松和白桦幼中龄林,将有利于提高该区森林碳汇潜力。

In order to estimate carbon storage and density variation of Larix and Betula young and middle forests in south and north Daxing＇ anling mountains,stand structure and biomass of Larix and Betula forests in the two districts were analyzed based on forest resource inventory in addition to the survey data for tending felling. The diameter distribution of Larix stands in the north was leftskewed,and the other right-skewed. The biomass densities of both forest types presented a near-to-normal distribution,even in the south and heterogeneous in the north. A linear relation between stand biomass and volume was identifi ed by correlation analysis,with B=0.6726V＋0.5592 for Larix and B=0.7317V-0.2932 for Betula. Carbon densities of Larix and Betula were respectively 30.54 t·hm-2 and 30.06 t·hm-2 in the south,and 24.19 t·hm-2 and 26.77 t·hm-2 in the north. Carbon storages of Larix and Betula of the entire region were 85.464 million ton and 27.989 million tonnes,and carbon densities 26.08 and 25.01 t·hm-2,respectively. Since carbon storage is far below its potential capacity,increase of carbon sequestration is expected by proper management of the forest ecosystems.