【摘要】 森林是陆地生态系统中最大的碳库。在全球变暖背景下,有关林业管理对森林碳库的影响引起各国科学家的日益关注。目前国内大多数文献都将森林采伐木碳库视为当年排放,而实际上采伐木能长时间储存碳。本文根据利用方式和采伐习惯,将采伐木按使用方式分为:1)DBH≤6cm为采伐剩余物置于林内;2)DBH>6cm为实木产品和纸制产品。以长白山林区典型地带性植被阔叶红松林为对象,通过调查采伐前后乔木组成的变化,根据采伐木碳库实际排放情况,研究了采伐前后森林碳储量的动态变化。结果表明:留于林内采伐剩余物为1.1tC.hm-2,排放速度由大变小,全部排放时间80年;实木产品碳储量为20.56tC.hm-2,前80年累计排放20.07tC.hm-2(97.71%);纸制产品为3.63tC.hm-2,前7年累计排放3.45tC.hm-2(95.13%)。若将采伐木碳库视为当年排放,则碳库采伐后20年才能达到采伐前的水平;而考虑采伐木碳库实际排放速率,碳库储量则一直大于采伐前水平。因此,将采伐木碳库实际排放列入考虑,有利于合理估算我国森林碳储量,对正确评价我国森林碳汇功能具有积极意义。更多还原

【Abstract】 Forest is the largest carbon (C) pool in terrestrial ecosystem. Under the background of global warming,the influence of forest management on the C pool is increasingly drawing the attention of scientists all over the world. Most of the literatures in China consider that the harvested wood products (HWP) discharge C at current year,but actually,the C in HWP can be deposited for a long time. According to the usage and harvesting practices of HWP,the HWP were divided as 1) harvested residues (DBH ≤6 cm),and 2) solid wood products and paper products (DBH >6 cm). This paper investigated the DBH and tree species composition before and after harvesting in the broadleaved-Korean pine mixed forests in Changbai Mountain,and studied the dynamic changes of the forest C storage,based on the actual emission of C from HWP. The results showed that the C storage of harvested residues was 1.1 t C,and the C emission speed changed from fast to slow. The total C emission would last over 80 years. The C storage of solid wood products was 20.56 t C,and the cumulated C emission in 80 years reached 20.07 t C (97.71%). The C storage of paper products was 3.63 t C,and the cumulated C emission would reach 3.45 t C (95.13%) in the first 7 years. If the C emission from HWP was considered at current year,the forest C pool would take 20 years to reach the level before harvesting; if considering the actual C emission from HWP,the forest C pool would be always larger than the level before harvesting. Therefore,it would be reasonable and meaningful to consider the actual C emission from HWP so as to accurately estimate the forest C storage in China.更多还原