Abstract
When there are multiple communities, ecologists often measure similarity or dissimilarity among communities by utilizing various similarity or dissimilarity measures. Beta diversity quantifies dissimilarity among communities. Species beta diversity only considers species relative abundances. In order to take species evolutionary history into account, this thesis also consider phylogenetic beta diversity. Since the observed species and phylogenetic beta diversity always overestimates the theoretical true value, this thesis develops new estimators by estimating species and phylogenetic gamma and alpha diversity respectively. On the other hand, in order to compare dissimilarity based on the different sampling effort, the thesis derives both theoretical formulas and analytic estimators for rarefaction and extrapolation of species and phylogenetic beta diversity. In order to compare the proposed new beta diversity estimators with traditional empirical method, computer simulation results are reported. The proposed estimators exhibit substantial improvement in terms of bias and RMSE. The proposed estimators are also applied to the analysis of rain forest data of Costa Rica, and to Italian dunes data. Online software Phylogenetic Diversity (PhD Online) is developed to implement all proposed measures and estimators.