湖南省武陵源地区的生物多样性和生态完整性

On the biodiversity and the ecological integrity of Wulingyuan district, Hu′nan Province

位于湖南省西北角的武陵源地区是中国境内自然生态环境保持较好的地区之一。该地区生物多样性丰富独特 ,表现为物种组成丰富 ,区系起源古老 ,地理过渡明显 ,特有类型众多 ,群落类型复杂 ,是不仅具有国家意义 ,而且具有世界意义的生物多样性的宝库。由于地形崎岖、山峰众多 ,境内最高峰近 1 90 0 m,最低处约 30 0 m,相对高差达 1 60 0 m;在纬度地带位置上 ,又居中亚热带气候带向北亚热带气候带的过渡 ,因而环境分化剧烈。加之人类活动影响较小 ,生态完整性保持较好 ,反映在昆虫多 ,但不造成危害 ;物种分化强烈 ,不同生态特性的相近物种在同一地点共存 ;位居多雨山区 ,但水清常流 。

The Wulingyuan District, located at the north western corner of Hu′nan Province is one of the districts with relatively intact ecological integrity within the territory of China. This district has plentiful and unique biodiversity, which displays in abundant species composition; ancient origin of flora and fauna; obvious geographical transition and numerous endemic types. It is a treasure house of biodiversity, not only with national significance, but also with world significance. Because of rugged topography with numerous high peaks, the altitude of the highest one approaches 1900m while the lowest valley nearby is about 300m, so the relative height difference reaches 1600m. Latitudinally, this district is situated at the transitional zone between the middle subtrapical and the north subtrapical, so its environment differentiates dramatically. In addition, the influence of human activities in this district till now is comparatively less, so it has better ecological integrity. This inflects in: (1) numerous kinds of insects (>2400 species) have been collected and identified here, and among them 77% are injurious pests, yet no plague of insects occurred in the forests; (2) Here the biological species differentiate strongly, and closed related but with different ecological characters species live side by side; (3) Though this is a mountainous region with plentiful and intense rainfall, yet the water in the streams and rivers are clear and permanent and there is no apparent soil erosion.