湖南小溪国家级自然保护区常绿阔叶林及其生态意义

湖南小溪国家级自然保护区地处华中武陵山脉中段，110°06′50″E-110°21′35″和28°42′15″-28°53′15″N之间，面积3 520 hm²，是我国常绿阔叶林保存比较完好的区域.初步研究结果表明该区常绿阔叶林主要包括钩栗林、湘西青冈林、巴东木莲林、利川润楠林、甜槠林、栲-银木荷林、湘西石栎林等，具备我国亚热带常绿阔叶林的一般特征，同时又具有较强的湿热特性和热带亲缘，可视为我国低海拔常绿阔叶林的典型代表，有利于我国亚热带地区生物多样性保护和生态环境维持.小溪常绿阔叶林不仅物种极为丰富，而且还拥有大量珍稀、孑遗和特有植物类群以及保存和孕育这些珍稀或特有种的河谷特殊生境，对研究我国乃至全球亚热带常绿阔叶林，揭示常绿阔叶林形成、分化，特别是河谷特殊生境物种多样性形成及其维持机制具有重要的理论意义与实践价值.

Characteristics of Evergreen Broad-Leaved Forest in Xiaoxi National Natural Reserve, Hunan Province and Its Ecological Significance

Xiaoxi National Natural Reserve of Hunan Province,located at the middle of Wulingshan Mountains in Central China,extending from 110°06′50″～110°21′35″ E and ,28°42′15″～28°53′15″N ,with an area 3 520 ha,is the one of well-protected typical evergreen broad-leaved forest in China.The preliminary results show that the evergreen broad-leaved forest of Xiaoxi,which mainly consists of Castanopsis tibetana forest,Cyclobalanopsis xiangxiensisi forest,Manglietia patungensis forest,Machilus lichuanensis forest,Castanopsis eyrei forest,Castanopsis fargesii,Schima superba forest and Lithocarpus xiangxiensisi forest,is a typical lower evergreen broad-leaved forest,because it possesses not only the general subtropical evergreen broad-leaved forest characteristics,but also the high hot -wet and tropical-temperate characteristics.It is favorable for biodiversity conservation and ecology-environmental maintenance.Xiaoxi evergreen broad-leaved forest is rich of species diversity,as well as the rare and endangered species,and the special ecological habitatenvironment of valleys,in which the species are bred and conserved.It is of important value and significance to study the subtropical evergreen broad-leaved forest in China or even in the whol
e world,expounding the mechanism of vegetation formation and evolution,specially the mechanism of species speciation,diversity and maintenance in valleys.