典型草原区植物群落结构特征动态监测

1999-2002年在内蒙古锡林郭勒盟白音锡勒牧场典型草原区海流特,监测主要植物群落结构特征。结果表明,随时间推移,试验区主要群落的优势植物大针茅、羊草相对高度、相对盖度、相对密度和相对生物量呈降低趋势,退化指示植物冷蒿、狼毒相对高度、相对盖度、相对密度、相对生物量呈增加趋势;试验区群落物种丰富度指数、多样性指数和均匀性指数随时间推移均呈降低趋势;围栏在试验区草地植物群落特征的保持方面很有效,但围栏内植物群落特征随时间推移仍呈退化趋势。

Dynamic Characteristics of Plant Community Structure in Typical Grassland

In the present study, we monitored the structure characteristics of the plant community in typical grassland of Baiyinxile pasture from 1999 to 2002. We found that during that time, the relative height, relative coverage, relative density, relative biomass reduced for those major plants such as Stipa grandis and Leymus chinensis. And those of degenerating indicator plants such as Artemisia frigida and Stellera chama-ejasme increased. In the main plant community, the role of plants with higher nutrition quality (Stipa grandis, Leymus chinensis, Festuca rubra, and so on) became smaller, and the role of lower nutritioa quality plants, such as Leontopodium leontopodioides, Heteropappus altaicus, Cleistogenes squarrosa,became larger, With the time passing, the abundance index of species, diversity index of species, uniformity index of the experimental area decreased. The fence was effective to keep the characteristics of community in the experimental area, but it could not prevent the plant from degenerating.