呼伦贝尔草甸草原不同放牧强度下植被特征分析

ANALYSIS OF VEGETATION CHARACTERISTICS UNDER DIFFERENT GRAZING INTENSITIES IN HULUNBER MEADOW STEPPE

该文利用草地的野外实测数据,计算了物种综合优势比、物种丰富度、物种多样性及其群落高度、盖度、密度、地上生物量等数量指标,对两种草甸草原样地三种放牧强度的群落结构和功能指标进行了研究。结果表明:从物种水平分析,羊草草甸草原样地(LM)和贝加尔针茅草甸草原样地(SM)的建群种的综合优势比随放牧强度加大而下降,而退化标志物种,如寸草苔、糙隐子草及冷蒿等呈上升趋势。从群落水平分析,LM样地比SM样地物种多样性维持能力弱,耐牧性弱。

The quantitative indices, such as summed dominance ratio, species richness, species biodiversity and community height, cover, density, and aboveground biomass, were calculated with the field sampling data, and then studied three grazing intensities of two meadow steppes which represent community structure and function. The results showed that the summed dominance ratio of edificators in Leymus chinensis meadow steppe （LM） and Stipa baicalensis meadow steppe （SM） decreased but the SDR of species increased, which indicated grassland degrada- tion with the grazing intensities went up from the perspective of species - level analysis. Furthermore, the capacity of biodiversity maintenance and grazing resistance in Leymus chinensis meadow steppe was weaker than that in Stipa baicalensis meadow steppe from the perspective of community - level analysis.