基于CENTURY模型模拟火烧对大兴安岭兴安落叶松林碳动态的影响  

Impact of fire on carbon dynamics of Larix gmelinii forest in Daxing'an Mountains of Northeast China:A simulation with CENTURY model

作　　者：方东明[1,2] 周广胜[1] 蒋延玲[1] 贾丙瑞[1] 许振柱[1] 隋兴华[1,2] 

机构地区：[1]中国科学院植物研究所,北京100093 [2]中国科学院研究生院,北京100049

出　　处：《应用生态学报》2012年第9期2411-2421,共11页Chinese Journal of Applied Ecology

基　　金：公益性行业(气象)科研专项(GYHY200706021)资助

摘　　要：火作为森林生态系统重要的自然干扰因子之一,对森林的碳动态有着不可忽视的影响.本研究使用CENTURY模型模拟了大兴安岭呼中林区兴安落叶松林的碳收支对不同强度火烧的响应.结果表明:在不同强度火烧后,土壤总碳库呈先升后降再逐渐恢复的变化趋势,而林分生物碳库则先降后升,其中,林分细小组分碳库的恢复速度明显快于大组分,各碳库的波动程度随火烧强度的增大而增大.森林植被的净初级生产力(NPP)和土壤异养呼吸在火后均先降后升,但NPP的恢复快于土壤异养呼吸,二者的动态变化改变了林分的碳源/汇作用.轻微火烧后,兴安落叶松林仍表现为弱碳汇,并很快恢复到火前水平;其他强度的火烧使兴安落叶松林在短期内(9"12年)表现为碳源,随后逐渐转为碳汇.较低强度的林火不仅可以促进落叶松林的更新、减少死可燃物,也不会对林分的碳汇功能造成太大影响;高强度的严重林火对土壤和林木碳库造成严重损失,延缓森林的恢复,并可使林分表现为较长时间的碳源.Fire is one of the important natural disturbances to forest ecosystem,giving strong impact on the ecosystem carbon dynamics.By using CENTURY model,this paper simulated the responses of the carbon budget of Larix gmelinii forest in Huzhong area of Daxing’an Mountains to different intensities of fire.The results indicated that after the fires happened,the soil total carbon pool of the forest had a slight increase in the first few years and then recovered gradually,while the stand biomass carbon pool increased after an initial decrease,with the recovery rate of carbon pool of the stand fine components being faster than that of the coarse components.The fluctuation of the carbon pools increased with the increase of fire intensity.After the fires,both the net primary productivity（NPP） of forest vegetation and the soil heterotrophic respiration increased after an initial decrease,but the recovery rate of the NPP was faster than that of soil heterotrophic respiration,resulting in the alternation of the stand functioned as a carbon source or sink.After light fire,the forest still functioned as a weak carbon sink,and quickly recovered as a carbon sink to the level before the fire happened.After other intensities fire,the forest functioned as a carbon source within 9-12 years,and then turned back to a carbon sink again.It was suggested that lower intensity forest fire could promote the regeneration of L.gmelinii forest,reduce the combustibles,and have no strong impact on the stand carbon budget,while higher intensity forest fire would lead to the serious loss of soil-and tree carbon sequestration,retard the recovery of the forest,and thereby,the forest would be a carbon source in a longer term.

关 键 词：CENTURY模型 碳动态 兴安落叶松 火烧强度 

分 类 号：S791.22[农业科学—林木遗传育种] S762[农业科学—林学]