四川小寨子沟森林群落物种多样性的环境梯度分析

Analysis on Environmental Gradients for Species Diversity of Forest Community in Xiaozhaizigou Nature Reserve，Sichuan

摘要:

运用去势典范对应分析法(DCCA)，分析了四川小寨子沟自然保护区森林群落物种多样性指数与环境因子的关系。结果表明，群落物种多样性表现为草本层>灌木层>乔木层；海拔高度是群落乔木层物种多样性分布格局的主导因素，随着海拔高度的上升，乔木层物种丰富度和多样性下降，而均匀度没有明显变化；土壤有机质和土壤全氮代表的土壤养分状况决定着灌木层和草本层物种多样性的分布格局。地形因子(如坡度、坡向等)与物种多样性没有明显的关系。

Abstract:

The variation patterns of species diversity of forest community in Xiaozhaizigou Nature Reserve were studied by systematic survey along altitudinal gradients, and the relationships between environmental factors and species diversities were analyzed by using Detrended Canonical Correspondence Analysis (DCCA). The results showed that the species diversities was in order of herb layer> shrub layer > tree layer. In tree layer, altitude was the most principal factor on distribution pattern of species diversity. With increment of altitude, species richness and diversity in tree layer decreased, and evenness of tree layer had no obvious changes. In shrub layer and herb layer, the soil nutrient status, such as the contents of organic matter and total nitrogen played important roles in distribution pattern of species diversity. There were not obvious relationships between species diversity and some topographic factors, such as slope, slope aspect, et al.