山西霍山森林群落林下物种多样性研究

在野外获得样方的基础上,采用多样性指数、丰富度指数、均匀度指数等对山西霍山森林群落林下灌木层和草本层的物种多样性进行了研究,结果表明,多数森林群落林下灌木层多样性指数和均匀度指数均高于草本层,而丰富度指数则相反。灌木层和草本层物种多样性指数的顺序为:针阔叶混交林>针叶林>落叶阔叶林,主要是由于针阔叶混交林兼有针叶林和落叶阔叶林的共同特征,因而具有较高的多样性。灌木层和草本层多样性指数、丰富度指数和均匀度指数在海拔梯度上呈单峰曲线变化趋势,即中海拔(1500 m)高度上物种多样性最大,这主要是由于在这一海拔范围内水热条件组合较好,人类活动干扰较少所致。

Species diversity of undergrowths in Huoshan Mountains of Shanxi Province

Based on the field investigation and by using the indices of diversity,richness and evenness,this paper studied the species diversity of shrub and herb layers under forest communities in Huoshan Mountains of Shanxi Province.The results showed that under most forest communities,the diversity and evenness indices of shrub layer were higher than those of herb layer,while the richness index of shrub layer was lower than that of herb layer.The species richness index was decreased in order of coniferous and broad-leaf mixed forest>coniferous forest>deciduous broad-leaf forest.Coniferous and broad-leaf mixed forest had higher species diversity than the others because it possessed the common features of both coniferous and deciduous broad-leaf forests.The peak values of these three indices of both shrub and herb layers were at the intermediate elevations about 1 500 m above sea level,where the combination of moisture and heat energy were favorable to the plant growth and development and with fewer human intervention.