水分梯度上放牧对内蒙古主要草原群落功能群多样性与生产力关系的影响

应用样线法对放牧对内蒙古草原沿水分梯度分布的主要植物群落:小针茅(Stipaklemenzii)群落、大针茅(Stipagrandis)群落、羊草(Leymuschinensis)群落和羊草杂类草群落多样性、生产力以及两者关系的影响进行了研究,结果表明,除羊草杂类草群落外,物种多样性、生活型多样性和水分生态类型多样性随放牧强度的加大而降低,但适度放牧增加了羊草杂类草群落的上述多样性指标。群落地上现存量一般随放牧强度的增大而下降,但小针茅群落反之,主要与1年生植物猪毛菜(Salsolacollina)的生物量迅速增加有关。除羊草群落外,其他群落0～10cm地下生物量随放牧强度的变化不显著;放牧显著降低羊草群落和羊草杂类草群落0～30cm地下生物量。多样性和生产力间的关系在群落水平上的趋势是不同的,但放牧影响下内蒙古草原4种群落多样性与生产力总体而言呈线性增加关系;同时两者之间的关系还和采用哪种多样性指标和生产力指标有关,用水分生态类型多样性比物种多样性更能反映与地上地下总生产力间的关系,得到放牧影响下内蒙古草原植物群落地上地下总生物量与水分生态类型多样性的回归方程。

Effect of grazing on the plant functional group diversity and community biomass and their relationship along a precipitation gradient in Inner Mongolia Steppe

There has been a rapidly increasing interest in the effect of species diversity or functional group diversity on ecosystem productivity. In order to search a general diversity-productivity pattern and find the mechanisms underlying the pattern, ecologists have undertaken many empirical studies. But the diversity-productivity connection still remains unclear. The main purpose of this study was to examine the effect of plant species diversity and functional group diversity on productivity of different communi...