喜马拉雅山东段鸟类多度-垂直分布幅关系:特有种与非特有种的对比

物种多度与分布幅之间的正相关被认为是一种普遍的规律。但近年在热带山地和岛屿的研究发现多度-分布幅关系会出现不相关或负相关的现象；该现象可能是由于当地多度高且分布幅小的特有种比例较高所导致。在喜马拉雅山东段的勒布沟沿海拔2350—4950 m开展研究：1)记录了当地鸟类多度垂直分布格局；2)验证了该区繁殖鸟总体多度-垂直分布幅关系，并对比了特有种和非特有种分组子集多度-垂直分布幅关系、平均多度和垂直分布中心的差异。研究发现勒布沟鸟类多度垂直分布格局为驼峰格局。该区繁殖鸟类与非特有种的多度-垂直分布幅关系均为正相关，但特有种的多度-垂直分布幅关系为不相关。特有种的多度及海拔分布中心位置均高于非特有种。结果表明区域的鸟类特有性对多度-垂直分布幅关系存在着重要的影响；地理隔离导致的区域物种组成差异，是造成多度-分布幅关系模式变化的重要原因之一。

Abundance-elevational range size relationship of bird in the eastern Himalayas: comparison of endemic species and non-endemic species

The positive relationship between species abundance and range size is considered to be general. However, many studies focusing on tropical mountains and islands have found an irrelevant or negative abundance-range size relationship, probably caused by the high proportion of endemic species with high abundance and large range size. The aim of this study was to 1) explore the bird elevational abundance pattern; 2) test the abundance-range size relationship of overall breeding birds, endemic species, non-endemic species, and the difference between mean abundance and elevational range center of endemic species and non-endemic species along the elevation gradient (2350-4950 m) in Lebu Valley, eastern Himalayas. Our results showed that the bird elevational abundance pattern was a hump-shaped pattern. The abundance-range size relationship of breeding birds and non-endemic species was both positive. But the abundance-range size relationship of endemic species was not correlated. Besides, the abundance and elevational range center of endemic species were higher than those of non-endemic species. The result demonstrated that the endemism of regional birds influenced the abundance-range size relationship, and the differences of regional species composition caused by geographic isolation were one of the important reasons for the variations of pattern of the abundance-range size relationship.