内蒙古典型草原4种常见小哺乳动物的营养生态位及相互关系

TROPHIC NICHES OF FOUR SPECIES OF COMMON SMALL MAMMALS IN INNER MONGOLIA GRASSLAND AND THEIR RELATIONSHIPS

本文根据布氏四鼠、达乌尔鼠兔、达乌尔黄鼠和草兔在自由生活下的食物组成，分别计算了它们之间的实际营养生态位重叠程度及生态位宽度。还计算了布氏田鼠、达乌尔鼠兔和达乌尔黄鼠间的原始营养生态位重叠程度及宽度。由于栖息地资源可利用性的限制，这３种小哺乳动物的实际营养生态位较原始营养生态位窄。分布空间的重叠可导致布氏田鼠与达乌尔鼠兔间实际营养生态位的较高程度重叠。此结果支持了ＭａｃＡｒｔｈｕｒ和Ｗｉｌｓｏｎ（１９６７）的生态位压缩假说。

In this paper, the realized trophic niche overlaps and breadths were calculated a mong Microtus brandti, Ochotona daurica, Citeilus dauricus and Lepus capensis respectively,according to the diet compositions under free-ling circumstances. Fundamental trophic niche breadths and overlaps of Microtus brandti, Ochotona daurica and Citellus dauricus were also measured based on the results of food selection tirals. Owing to the restriction of food availabil ity in the habitats, the realized trophic niche breadths of Microtus brandti Ochotona daurica and Citellus dauncus were more narrow than their fondamental ones, respectively. The overlap of local distribution spaces between Microtus brandti and Ochotona daurica might be lead t6 quite larger overlap of their realized trophic niches. The results of this paper supported MacArthur and Wilson' s compression hypothesis.