武夷山中亚热带常绿阔叶林林隙动态及自然干扰特征

STUDIES ON THE GAP DYNAMIC AND THEIR NATURAL DISTURBANCE CHARACTERISTICS IN WUYISHAN MOUNTAIN MID-SUBTROPICAL EVERGREEN BROAD-LEAVED FORESTS

对武夷山自然保护区星村镇桐木村茅排及观测站附近天然林中3个样地共25个林隙进行调查，探讨了武夷山中亚热带常绿阔叶林林隙动态及自然干扰规律。该天然林林隙形状近似于椭圆形，椭圆的长短轴比率EG和CG有所不同，平均分别为1．36和2．14；扩展林隙（EG）和树冠空隙（CG）在亚热带常绿阔叶林景观中的面积比例分别为80．18％和28．37％，干扰频率分别为1．604％·a^-1和0．567％·a^-1。林隙干扰返回间隔期约为176a。EG大小一般变化在140—613m^2左右，平均约为241m^2，大多数CG大小一般都变化在75～467m。左右，平均约为85．1m^2。林隙一般是在50a以内形成的，而30～40a之间形成的林隙最多。大多数林隙是由1—3株形成木创造的，而由1株形成木创造的林隙最多。林隙形成木通过于基折断死亡的形式存在。星村镇桐木村茅排及观测站附近天然林中的林隙主要是由10多个树种创造的，其中不仅有第1层的树种，而且还有第2、3层的树种。最后以林隙动态理论为基础，对武夷山常绿阔叶林的经营管理提出了参考意见。

Based on field investigation of 25 gaps in natural forests in Maopai and near the Observation Station, Tongmu Village, Wuyishan Mountain National Nature Reserve, this paper studies on gap characteristics and their natural disturbance characteristics in Wuyishan Mountain mid - subtrop- ical evergreen broad - leaved forests. Gaps in the natural forest are nearly elliptic in horizontal form, and the ratio of long axis/short axis for each gap is a little different with about 1.36 for expanded gap （EG） and 2.14 for canopy gap （ CG）. The area percentage of EG and CG in the forest landscape is 80.18% and 28.37%, respectively. The natural disturbance frequency for EG and CG is 1. 604% ·a^-1 and 0. 567% · a^-1 , respectively, and the return interval of canopy gaps is about 176 a. The size of most EG in the subtropical evergreen broad - leaved forest range from 140 m^2 through 613 m^2, average about 241 m^2, and the size of CG in the forest range from 7 m^2 through 467 m^2, average about 85.1 m^2. The gaps were frrmed usually within 50 years, and most of which aged 30 - 40 a. Most gaps were made by 1 -3 gap makers, of which I gap maker gaps are the majority. The dead gap makers are broken at trunk base. Major gap makers are more than 10 tree species, in which there are not the only tree species in the first canopy layer, but also tree species in the second and third layers. Finally, based on the Studies of gap dynamic, some suggestions are carried out to manage the evergreen broad -leaved forests in Wuyishan Mountain.