阔叶红松林乔木地上碳储量和碳增量对采伐强度的响应  

Responses of tree aboveground carbon storage and carbon increment to logging intensity in a broadleaved Korean pine forest

作　　者：耿燕[1] 赵秀海[1] 安黎哲 Geng Yan;Zhao Xiuhai;An Lizhe(Research Center of Forest Management Engineering of State Forestry and Grassland Administration,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学国家林业和草原局森林经营工程技术研究中心,北京100083

出　　处：《北京林业大学学报》2022年第10期23-32,共10页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(32171521)。

摘　　要：【目的】采伐是影响森林植被固碳能力最主要的森林管理方式之一。目前对异龄复层混交林植被碳储量和碳增量对采伐干扰的响应规律尚缺乏足够的认识。本研究旨在揭示不同强度采伐下阔叶红松林乔木地上碳储量和碳增量的动态变化,为合理选择采伐强度,促进阔叶红松林“固碳增汇”提供理论依据。【方法】在吉林蛟河天然阔叶红松林内建立轻度(胸高断面积平均采伐强度17.3%)、中度(34.7%)、重度(51.9%)采伐以及对照(不采伐)样地,对样地内所有胸径大于1 cm的乔木进行连续监测,比较不同采伐强度下保留木、进界木、枯死木碳储量的变化,以及采伐对不同径级树木碳增量的影响,探究采伐干扰后林分碳储量恢复的一般规律和限制因素。【结果】采伐10年后,轻度采伐样地内的乔木地上碳储量已经恢复到伐前水平并超过对照样地,而中度和重度采伐造成的碳储量损失在短期内难以恢复,分别需要约22年和44年才能恢复到伐前水平。乔木地上碳增量在4个采伐强度中有显著差异。轻度采伐使得林分碳年增量显著高于对照,而重度采伐却明显降低了碳增量的增速。这是因为尽管采伐显著提高了林分保留木和进界木的生长量,但高强度采伐造成的林内环境变化、树木受伤等增加了样地内树木的死亡率,使得净碳增量较低。采伐对小径级树木(胸径小于20 cm)的生长(碳增量)有显著的促进作用,而大径级树木(胸径大于30 cm)的碳增量在不同采伐处理之间没有显著影响。将采伐强度与碳增量进行拟合,得到采伐强度为28.4%时碳储量年增量达到最大值。【结论】从本研究结果来看,阔叶红松林的采伐强度在15%~30%是较为合理的。轻度到中度的采伐尽管在短期内会引起植被碳储量一定程度的降低,但通过对林分结构进行调整,加速了保留木和进界木的生长,使得碳增量较快。同时[Objective]Logging is one of the most important forest management methods affecting the carbon sequestration capacity of forest vegetation.At present,there is a lack of understanding in the response of vegetation carbon storage and carbon increment in uneven aged multi-layer mixed forest to logging disturbance.The objective of this study was to reveal the dynamic changes of tree aboveground carbon storage and carbon increment of broadleaved Korean pine forest following logging of different intensities,and thus providing a theoretical basis for optimizing logging intensity to promote carbon sink potential of the broadleaved Korean pine forest.[Method]We established four permanent sample plots in a broadleaved Korean pine forest in Jiaohe,Jilin Province of northeastern China,ranging in logging intensities from low(17.3%of basal area removed on average),medium(34.7%)to high(51.9%),together with an unlogged control sample plot.Growth,recruitment and mortality of all individual trees with DBH greater than 1 cm were documented.Changes in carbon storage due to growth,recruitment and mortality were compared among different logging intensities,as well as among tree size classes.[Result]Tree aboveground carbon storage in the low sample plot was recovered to pre-logging level within 10 years.The accumulated carbon storage in the low logging sample plot was even greater than the control.Nevertheless,the loss of carbon storage due to logging in medium and high logging sample plots was hardly compensated by increasing tree growth within a short period,and about 22 and 44 years were needed for medium and high logging sample plots,respectively,to recover to their pre-logging levels.Net carbon storage increment differed significantly among the four treatments.Compared with control,low intensity logging promoted the annual increment of carbon storage,while medium to high logging resulted in a remarkable low rate of carbon increment.Although logging enhanced the growth of survivors and recruitment,heavy logging altered the understo

关 键 词：森林碳储量 保留木 进界木 枯死木 采伐干扰 

分 类 号：S791.247[农业科学—林木遗传育种]