Abstract:

In order to explore the effect of grazing intensity on Seriphidium transiliense desert grassland, the population characteristics and community diversity of S. transiliense under different grazing intensities were studied by the field surveys and laboratory analysis from 2012 to 2014 in Ashili country, Changji City. The results showed that the height, coverage and biomass of S. transiliense, Compared with no grazing, were decreased with increasing grazing intensity, and decreased by 73.7%~90.9%, 34.8%~95.9%, 67.9%~98.1%, respectively. The density of S. transiliense exhibited a single peak curve with increasing grazing intensity, and light grazing reached the peak, 63.4% more than the density of no grazing. Diversity index and evenness index of communities appeared a gradually increasing trend and species richness index showed the trend of increase-decrease-increase with increasing grazing intensity. It indicates that S. transiliense populations gradually become dwarf and degradation with increasing grazing intensity and moderate grazing is beneficial to maintain the stability of community structure.

Key words: Seriphidium transiliense, Grazing intensity, Population characteristics, Community diversity

摘要：

为探究放牧强度对伊犁绢蒿(Seriphidium transiliense)荒漠草地种群特征及其群落多样性的影响,2012-2014年连续3年采用野外取样和室内分析相结合的方法,对新疆昌吉市阿什里乡处于不同放牧强度下伊犁绢蒿种群特征及其群落多样性进行了研究。结果表明:随着放牧强度增加,伊犁绢蒿种群高度、盖度、生物量呈下降趋势,与对照比,放牧后分别降低了73.7%~90.9%,34.8%~95.9%,67.9%~98.1%;种群密度随放牧强度的增加呈单峰曲线变化,且在轻度放牧达到最高,较对照增加了63.4%以上;群落的Shannon-wiener指数、Pielou指数总体呈逐渐增加趋势,而Patrick指数呈先升后降再升高变化趋势。总之,随放牧强度的增加伊犁绢蒿种群特征逐渐向低矮、退化方向演替,适度放牧有利于群落结构稳定性的保持。

关键词: 伊犁绢蒿, 放牧强度, 种群特征, 群落多样性