天童国家森林公园主要森林植被过去30年的动态变化

Dynamics of major forest vegetations in Tiantong National Forest Park during the last 30 years

在气候变化和人类干扰的双重影响下,植被的演替和发展是生态学研究的热点之一,也是关系到人类社会可持续发展的一个重要问题.以浙江天童国家森林公园6种森林植被类型(典型常绿阔叶林的3个亚群丛、常绿落叶阔叶混交林、常绿针叶林和毛竹林)为研究对象,对比分析1982年和2012年其物种组成、群落结构和物种多样性等变化特点.结果表明:30年间群落的整体空间格局保存完好,群落分布未发生质的变化,主要优势植物种类变化不大;群落中幼树所占比例上升,小径级个体增多,群落更新状况良好且自然更新能力增强;乔木层物种多样性增高,常绿成分增加,灌木和草本层物种多样性下降.在过去30年里,随着温度上升,该地主要森林群落呈正向演替趋势,表明天童森林群落受到了较好的保护,也表明气候变化与常绿阔叶林的演替和发展存在一定的潜在正相关.

The study of vegetation succession and development is not only one of the hot spots of modem ecology, but also a key issue of the sustainable development of human society, especially under the circumstances of climate change and anthropogenic disturbance. A comparison of forest communities in the Tiantong National Forest Park （TNFP） in Zhejiang Province, eastern China from 1982 to 2012 was performed. Six forests in the park were investigated, including the typical evergreen broadleaved forest （EBLF, three sub-associations）, evergreen and deciduous broad leaved mixed forest （EDBLMF）, evergreen conifer forest （ECF） and bamboo forest （BF）. Data from two field investigations in 1982 and 2012, respectively, were used to analyze the changes of species composition, community structure and species diversity during the past 30 years. The spa- tial pattern and community structure of the forest vegetation in the TNFP did not obviously change. The spatial distribution of plant communities did not significantly shifted. The proportion of young trees and individuals in small diameters increased. The regeneration status of communities was healthy and the natural regeneration ability of communities was enhanced. The species diversity of the TNFP forests showed an increasing trend in the tree layer and a decreasing trend in the shrub and herb layers. Meanwhile, the evergreen component increased. Along with the changed climate, forest vegetation in the TNFP was developing towards the forward succession. Species diversity, es- pecially the trees, increased with the increase of temperature. This demonstrated that, on one hand, forest vegetation in Tiantong had been well protected; on the other hand, there was a poten-tial positive relationship between the EBLF succession and climate change.