模糊聚类指数和自组织神经网络指数在自然群落功能多样性研究中的应用

Methods for measuring functional diversity are basis of community studies. Two newly functional diversity indices, fuzzy clustering index (fuzzy index) and self-organizing feature map index (SOFM index), were applied and tested in functional diversity analysis in plant communties. The algorisms of these two methods were introduced and theoretically analized. Thirty quadrats of Axanthopanax senticosus communities were established in the Dongling Mountains in China and species composition, traits and environmental variables were measured and recorded. Eleven functional traits were used in the calculation of functional diversity. The results showed that fuzzy index and SOFM index were effective methods in functional diversity studies. Fuzzy index and SOFM index provided similar results to that of other common methods. Functional diversity in Axanthopanax senticosus communities varied obviously; functional diversity was significantly correlated with slope and elevation; functional diversity was positively correlated with species richness, heterogeneity, and negatively correlated with evenness.