华西雨屏带及其对我国生物多样性保育的意义

The concept of the Rainy Zone of West China and its significance to the biodiversity conservation in China

华西雨屏带为四川盆地西部边缘独特的自然地理区域。东西宽 5 0～ 70km ,南北长 4 0 0～ 4 5 0km ,总面积约2 .5万km2 ,仅占我国国土总面积的 0 .2 6 %左右。本区以自然风景优美、天然植被类型丰富、动植物资源种类多样而享誉中外。迄今为止 ,尚未将华西雨屏带作为相对独立的自然地理单元来研究其生物多样性。本文从当地剧烈的地形、地貌变化 ,特殊的气候、植被类型与动物栖息环境以及邻近人类聚居区的特点入手 ,扼要阐述了本区生态系统与环境的多样性状况。进一步通过对当地动植物种类 ,尤其是种子植物、兽类、鸟类、鱼类物种多样性与珍、稀、危、特保护物种的数量比重分析 ,提出了本带作为我国乃至世界上研究与保护生物多样性的热点区域的立论依据。华西雨屏带是一个大尺度、复合性的生态过渡带 (ecotone) ,是我国西部地区以阴湿为主要特征的罕见的气候地理单元 ,是我国西部生态保护与建设的一道绿色屏障 ,是我国生物多样性保护与研究不可替代的关键地区之一。

The Rainy Zone of West China, which is located along the brim of the Sichuan Basin, ranges 50～70 km east to west and 400～450 km from north to south, with an area of 25 000 km 2 or 0.26% of the territory of China. This zone is well known for its beautiful landscapes, plentiful vegetation types, abundant resources and diversity of plants and animals. Unfortunately, the zone has not been recognized as a relatively isolated geographic unit and the biodiversity in the zone has not been studied. Through analyzing the extremely varying topography and landforms, special climate, unique vegetation types and species of plants and animals, and the populated areas in the zone, this paper briefly discusses the diversity of ecosystems and habitats of the zone. The rainy zone is a large scale and complicated ecotone that is a natural geographic unit, with a cloudy, wet climate as its main feature. It is a green barrier for ecological protection and development in western China, and a key region for biodiversity conservation and research in China. The results of this paper offer support for the suggestion that Rainy Zone of West China should be listed as a key ecological region of China and the world.