湘西北蜡梅群落特征的初步研究

从５个样地９００ｍ２的调查资料对湘西北蜡梅群落进行了初步分析，结果表明：（１）群落种类组成丰富，共有维管束植物８０科，１３０属，１６６种。地理成分复杂，温带成分略占优势并表现出由热带向温带渐次过渡的性质；（２）外貌特殊，主要由革质、单叶和中型叶为主的落叶高位芽植物所决定，季相交替明显并与其他植被显著不同；（３）群落结构可分为林木层、小灌木层、草本层和地被层，其中林木层还可分为３个亚层，各层均以蜡梅占优势。林木结构分析表明，该群落具有一定的稳定性，属于亚热带区域的一类次生的暖性落叶阔叶灌丛，建议加强保护与开发利用的研究。

PRELIMINARY STUDIES ON PHYTOCOENOLOGICAL FEATURES OF WINTERSWEET (CHIMONANTHUS PRAECOX) COMMUNITY IN NORTHWEST HUNAN PROVINCE, CHINA

This paper deals with the habit, floristic composition and phytocoenological features of wintersweet (Chimonanthus praecox) community in Northwest Hunan with reference to information of 900 m 2 and 5 samples. The results show: (1) The floristic elements of the community are complex, the temperate elements are slightly dominated in the community. This condition indicates a transitional feature of plant distribution from tropical to subtropical in nature. (2) The distinguishaed physiognomy of the community is indicates by the deciduous phaenerophytes with feathery, simple and mesophyteus leaves and the very clear replacement of seasonal aspect. (3) The community can be structurally divided into three layers, the tree layer, shrub layer, herbaceous and ground layer. The tree layer can be subdivided into three layers too. Chimonanthus praecox population occupies a dominate position in every layer. According to analysis on the relation between tree heigh and DBH distribution and individual number in the community, it may be seen that this community is a relatived stable secondary forest which belongs to deciduous broadleaved bush formation.