长白山西坡风灾区森林恢复状况

Forest recovery state in wind disaster area of Changbai Mountains,Northeast China

以长白山西坡风灾迹地(阔叶红松林、云冷杉林、岳桦林)的样地调查资料为基础,研究了各林型森林群落遇灾23年后的恢复特征.结果显示:3种林型的恢复速度为阔叶红松林>云冷杉林>岳桦林,并且它们与各自对照的群落共有度指数分别为0.49、0.44、0.33.风灾对各林型的乔木组成和多样性的影响不同:阔叶红松林中,风灾显著增加了乔木总数量,但对乔木种数和α多样性指数没有显著影响(P>0.05);云冷杉林中,风灾仅显著降低了Shan-non多样性指数和Simpson优势度指数;岳桦林中,除Pielou均匀度指数,其余多样性指数都因风灾而显著降低.各林型优势树种组成变化及更新情况对风灾的响应也与林型相关:阔叶红松林与对照区的优势树种组成显著不同,而云冷杉林及岳桦林受灾前后的优势树种组成差异均不大;阔叶红松林的幼树更新情况较好,云冷杉林有少量更新,岳桦林带几乎没有林木更新.表明风灾对森林群落的影响在23年后仍未消除,森林在风灾干扰后的恢复需要一个漫长的过程.

Based on the field investigation in windfall areas of Changbai Mountains,this paper studied the community recovery characteristics of broad-leaved Korean pine forest （BKPF）,spruce fir forest （SFF）,and Erman＇s birch forest （EBF） that were disturbed by wind disaster 23 years ago. The recovery rate of these three forest types was in the order of BKPFSFFEBF,and their total community index was 0.49,0.44,and 0.33,respectively. The effects of the wind disaster on the forest tree species composition and diversity were different. In BKPF,the total number of trees increased significantly,but the tree species number and α diversity index had no significant change; in SFF,only the Shannon diversity index and Simpson dominance index decreased significantly; while in EBF,all diversity indices except Pielou evenness index had significant decrease. The responses of dominance tree composition and regeneration to the wind disaster depended on forest types. Comparing with the plots not suffered from wind disaster,the BKPF under wind disaster disturbance had greatly different dominance tree compositions,but the difference in both SFF and EBF was not significant. The BKPF＇s sapling regeneration was fairly good,while the SFF＇s was small,and EBF almost had no sapling regeneration. All the results suggested that the effects of wind disaster disturbance on the test forest ecosystems in study areas was not removed even after 23 years,and the recovery of forest after wind disaster disturbance needs a relatively long time.