A measure of beta diversity is proposed for equal sized presence absence vegetation plots. The method begins by computing the minimum variance unbiased estimator of the expected species richnesE[Sn] as a function of sample size n for a set of N plots. Using semilogaritmic relation, beta-diversity is then determined from the slope of the best fitting line of the E[Sn] vs. log n plot. Beta-diversity is thus interpretable as the linear relation between expected species richness and log samples size. The method illustrated using 15 square plots of 100m2 each from a Matorral community in the rid Chaco of central Argentina. Further, some analogies between the proposed method and Wittaker’s multiplicative model of beta diversity are discussed.
Computing beta diversity from species-area curves
CARRANZA, Maria Laura
2002
Abstract
A measure of beta diversity is proposed for equal sized presence absence vegetation plots. The method begins by computing the minimum variance unbiased estimator of the expected species richnesE[Sn] as a function of sample size n for a set of N plots. Using semilogaritmic relation, beta-diversity is then determined from the slope of the best fitting line of the E[Sn] vs. log n plot. Beta-diversity is thus interpretable as the linear relation between expected species richness and log samples size. The method illustrated using 15 square plots of 100m2 each from a Matorral community in the rid Chaco of central Argentina. Further, some analogies between the proposed method and Wittaker’s multiplicative model of beta diversity are discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
