福建梅花山常绿阔叶林植物物种多样性及其海拔梯度格局

常绿阔叶林是福建梅花山国家级自然保护区地带性植被。采用样带与典型群落调查法对区内的常绿阔叶林14400m2样地展开调查，并对植物多样性海拔梯度格局进行分析，结果表明：（1） 群落植物物种丰富度、Gleason丰富度指数、Simpson指数、Shannon Wiener指数和Pielou均匀度指数的均值分别为64.42、10.75、5.75、3.50、0.58，且这5种指数在各样带间差异极为显著，并随海拔的升高均呈单峰曲线变化，峰值出现在海拔700m~900m。（2） 群落各层次的植物物种丰富度、Shannon Wiener指数均呈现灌木层（包括幼树和层间植物）〉乔木层〉草本层的特征。乔木、灌木层物种丰富度与乔木层Shannon Wiener指数在海拔梯度上的样带间差异极显著，变化趋势与群落相似；灌木层与草本层Shannon Wiener指数以及草本层物种丰富度随海拔梯度变化不明显。因此，梅花山自然保护区常绿阔叶林植物物种多样性的海拔梯度格局呈现单峰分布，并支持中间高度膨胀模式（mid domain model）。

Species Diversity and Altitudinal Gradient Patterns of Evergreen Broad-leaved Forest in Meihuashan National Natural Reserve, Fujian Province

In China, evergreen broad leaved forests （EBLFs） is one of the most important vegetation types which was widly distributed in subtropical area, and it plays a very important role in the global biological diversity and natural environment conservation also. In order to reveal species diversity and altitudinal gradient patterns of evergreen broad leaved forest in Meihuashan National Natural Reserve, Fujian Province. Five altitude transects were set up at a vertical interval of 200m between 375m and 1300m above sea level in the EBLFs distribution areas, and twenty four quadrats（14400m2） had been surveyed. Species richness（S）, species richness index （dGl）, Simpson index （D）, Shannon Wiener index （H′）, Pielou evenness index （J） had been used for analysis of species diversity and altitudinal gradient pattern of EBLFs. The average value of S, dGl, H′,J and D were 64.42, 10.75, 5.75, 3.50, 0.58 respectively. The difference of community species diversity index（S, dGl, D, H′, and J） was extremely significant between transects, and the altitudinal gradient patterns of species diversity presented the unimodal variable trend, with a peak in the mid altitude（700m-900m）. The species richness and Shannon Wiener index of different layer were ranked as shrub layer （include young tree and the plants between layers）〉arbor layer〉herb layer. The species richness of tree and shrub layer, and Shannon Wiener index of tree layer were significantly different between at transects, and trends of altitude gradient was similar to community. The Shannon Wiener index of shrub layer and herb layer, and the species richness of herb layer did not change significantly along elevation gradient. Therefore, plant species diversity distribution pattern presented a unimodal variable trend along an elevation gradient, and supported “mid domain model” in EBLFs of Meihuashan National Nature Reserve.