不同放牧强度对草原鸟类群落多样性的影响

对红花尔基林业局不同放牧强度草地内鸟类群落结构进行调查的结果表明:在正常草地、轻度放牧、中度放牧和重度放牧草地内共观察到23种鸟类,其鸟类多样性指数分别为0．74、0．89、1．05、0．49。各放牧强度样地内的鸟类多样性指数之间的差异显著。沙(即鸟)的密度随放牧强度的增加而增加,并在重度放牧草地内达到最大,而蒙古百灵、小沙百灵和鹌鹑的密度则逐渐降低。从正常草地至中度放牧草地云雀的密度逐渐增加,在中度放牧草地内达到最大。

Effect of Grazing Intensity on Bird Community Diversity

The bird community structures were studied in grasslands with different grazing intensities in Honghuaerji Forestry Bureau , and a total of 23 species of birds are recorded. Results showed that the bird diversity indexes in the sites with no grazing, light grazing, medium grazing and heavy grazing were 0.74, 0. 89, 1.05 and 0.49, respectively. The bird diversity indexes were significantly different between the grasslands with different grazing intensities. The densities of Oenanlhe isabellina increased as grazing intensity went up and reached to the maximum at heavy grazing intensity, while the densities of Melanocorypha mongolica, Calandrella cheleensis and Coturnix coturnix decreased with increasing grazing intensity. The densities of Alauda arvensis increased gradually from no grazing to medium grazing grasslands; however, the diversity reached its highest value at medium grazing intensity.