深圳坝光区域自然林及半自然林植物多样性比较

实地调查深圳市坝光区域2个封育状态下的自然林和2个处于恢复状态的荒弃果林半自然林的植物群落结构，测定植物高度、盖度等指标，分析两种类型植物群落组成及多样性特征。结果表明，在群落各层次的种类组成方面，自然林乔木层与灌木层的植物种类数均大于半自然林，半自然林的灌木层与草本层发育也较好，种类丰富；在物种多样性Simpson指数、Shannon-Wiener指数和丰富度指数方面，4个群落的灌木层多样性都较其他2个层次高，说明在人为干扰减小的情况下，灌木的自我更新能力较强。自然林3个群落层次及整体指标等多数高于半自然林，说明自然林植被结构发育较好，各层次种类数更为丰富，各种类个体数及分布更为均匀；而处于恢复状态的半自然林，由于受到人为干扰的印迹未完全消失，乔木层的多样性指数明显低于自然林，但也因为处于恢复状态，灌木层与草本层的恢复使其物种多样性逐渐增高。

Comparison of Plant Diversity Between Natural Forest and Semi-natural Forest in Baguang,Shenzhen

The plant community structures of two sealed natural forests and two restored abandoned semi-natural forests in Baguang area of Shenzhen were investigated, the plant height, coverage and other indexes were measured, and the composition and diversity characteristics of the two types of plant communities were analyzed. The results showed that in terms of species composition at all levels of the community, the numbers of plant species in tree layer and shrub layer of natural forest were greater than those of semi-natural forest, and the shrub layer and herb layer of semi-natural forest were also well developed and rich in species. In terms of species diversity Simpson index, Shannon Wiener index and richness index, the shrub layer diversity of the four communities was higher than the other two layers, indicating that the shrub had strong self-renewal ability under the condition of reduced human disturbance. Most of diversity indexes of the three community layers and overall indexes in natural forest were higher than those of semi-natural forest, indicating that the vegetation structure of natural forest was well developed, the number of species at each level was richer, and the number and distribution of individuals of various classes were more uniform. In the restored semi natural forest, due to the imprint of human disturbance, the diversity index of tree layer was significantly lower than that of natural forest, but also because it was in the restored state, the species diversity was gradually increased by the restoration of shrub layer and herb layer.