Comparison of the components of breeding bird communities in the grasslands of Inner Mongolia, China
内蒙古草原繁殖鸟类群聚组成之比较

A census of breeding birds was carried out in the vegetation of steppe, typical grassland, wet grassland, sand grassland, and mountain forest grassland in May, 1998 in the temperate steppe of Inner Mongolia, China. Eleven 100 hm 2 plots with three transect lines , each 150m apart, were studied. Meanwhile, 1m 2 of vegetation within each plot was used for recording plant species, vertical height, coverage, and weight.As the results indicated, the numbers of species of breeding birds in the grasslands of Inner Mongolia were low. There were 4~6 species in steppe, 5~8 species in typical grassland, 15 species in wet grassland, 9~12 species in sand grassland, and 6 species in mountain forest grassland. Bird species diversity and richness index were also low. In descending order were sand grassland, wet grassland, mountain forest grassland, typical grassland, and steppe. Bird densities in order from large to small were wet grassland, typical grassland, steppe, sand grassland, and mountain forest grassland. As for the food habit distributions of breeding birds, in the steppe and typical grassland omnivores were dominant, in the wet grassland insectivores were dominant, in the sand grassland omnivores and carnivores were dominant, and in the mountain forest grassland insectivores and omnivores, followed by carnivores were dominant.