湘西北蜡梅群落典型样地的物种多样性特征初探

根据湘西北野生蜡梅〔Ｃｈｉｍｏｎａｎｔｈｕｓｐｒａｅｃｏｘ（Ｌ．）Ｌｉｎｋ〕群落典型样地的调查结果，对其物种多样性指数及其特征进行了综合测算与分析，结果表明：群落各层次的种群数量分布与多样性指数（除优势度指数外）的变化规律基本一致，从乔木层到草本层依次递增，显示出其林冠层下能够容纳丰富的物种多样性。将不同区域的样地之间多样性综合指标进行比较，并结合林木径级构成分析，发现处于人为活动影响下的蜡梅群落，其物种多样性逐渐退化，群落的发育速度减缓；而处于自然演替中的群落，其多样性综合指标较高，群落结构复杂且较稳定，顺向演替进程加快

Preliminary research on species diversity characteristics of the typical sample plots of Chimonanthus praecox community in northwest Hunan Province\

Based on the field investigation on the typical sample plots of Chimonanthus praecox (L.) Link community in northwest Hunan Province, China, the species diversity indices and their characteristics of the community were calculated and analyzed. The results showed that in all layers of the community, the population quantity and the diversity indices (except dominance index) vary consistently; they increase in order from tree layer to herb layer; under the tree crown layer, the species diversity was more abundant. Comparing the synthetic diversity indices of sample plots from different regions and analyzing the DBH, it was discovered that the species diversity of the C. praecox community, disturbed by activities of human being, has gradually deteriorated, the progressive succession of the community slowed down, whereas the synthetic diversity indices of the community in natural succession were high increased distinctly, the community structure was more complicated and stable, and the community succession speeded up.