小兴安岭天然森林沼泽生态系统碳汇功能

Carbon Sink in Natural Swamp Forest Ecosystems in Lesser Xing'an Mountains

为了定量评价小兴安岭森林沼泽生态系统碳汇潜力,在伊春市友好林业局岭峰林场设立了标准地,采用静态暗箱—气相色谱法测量土壤CO2和CH4的排放通量,调查小兴安岭5种天然森林沼泽生物量,并建立了生物量回归模型,以推测乔木净初级生产力。研究结果表明:5种森林沼泽各类植被物种碳质量分数范围为40.2%～49.3%,毛赤杨(Alnus sibirica)沼泽、白桦(Betula platyphylla)沼泽、落叶松(Larix gmelinii)—苔草(Carex schmidtii)沼泽、落叶松—藓类(Moss)沼泽和落叶松—泥炭藓(Sphagnum spp.)沼泽植被净固碳分别为161.202、73.562、42.18、205.02、295.33 g.m-2.a-1,小兴安岭天然毛赤杨沼泽、白桦沼泽、落叶松—苔草沼泽、落叶松—藓类沼泽、落叶松—泥炭藓沼泽土壤排放的碳(包括CH4折算成的碳)分别为226.49、253.57、191.86、169.53、127.33 g.m-2.a-1,小兴安岭天然白桦沼泽、落叶松—苔草沼泽、落叶松—藓类沼泽、落叶松—泥炭藓沼泽生态系统分别是大气CO2净吸收碳汇19.99、50.323、5.491、68.00 g.m-2.a-1,毛赤杨沼泽为大气CO2净排放碳源(65.29 g.m-2.a-1)。

A survey was conducted to quantitatively evaluate the potential of carbon sink in five types of natural swamp forests in Lesser X.ing＇ an Mountains, Northeast China. Biomass of the swamp forests was determined by setting up standard plots at Youhao Forestry Bureau of Yichun City. Soil fluxes of CO2 and CH4 were measured by static opaque chamber and gas chroma- tography techniques. Regression models for biomass were established for predicting net primary productivity of trees. Results showed that the carbon concentration of all plant species in the five types of swamp forests ranged from 40.2% to 49.3%. The net carbon fixed by plants in A/nus sibirica swamp, Betula platyphylla swamp, Lar/x gmelinii-Carex schmixkii swamp, L. gmeli- nii-moss swamp, and L. gmelinii-Sphagnum spp. swamp were 161.20,273.56,242. 18,205.02, and 295.33 g·m^-2·a^-1 , respectively. The carbon emissions from soils, including conversion of CH4 into carbon, in A. sibirica swamp, B. platyphylla swamp, L. gmelinii-C, schmidtii swamp, L. gmelinii-moss swamp and L. gmelinii-Sphagnum spp. swamp were 226.49, 253.57, 191.86, 169.53 and 127.33 g ~ m-2 ~ a-＇, respectively. The COz-C sinks in B. platyphylla swamp, L gmeli- nii-C, schmidtii swamp, L. gmelinii-moss swamp, and L. gmelinii-Sphagnum spp. swamp were 19.99, 50.32, 35.49 and 168.00g·m^-2·a^-1 , respectively, while the source of C02-C from A. sibirica swamp was 65.29 g·m^-2·a^-1.