Advances in research on the species-abundance relationship models in multi-species collection

Species-abundance relationship, one of the most fundamental aspects of community structure, is a very interesting and important issue in community ecology. In resent years, this subject has received more attention, its research ranges have been greatly expandedsuch that the concept of related “community” has been extended to “multi-species collection”, and the measurement of “abundance” of a species has been extended to “generalized abundance”. Related papers have been increased dramatically, most notably from 1994 to 2002. There are regularities in the abundance of species in communities such as plants and moths in a forest or algae inhabiting a nearby stream. In most cases, many species are very rare and few very common in a community sampled. Yet if the community is thoroughly sampled, a few species are abundant, a few very rare, and most moderately abundant. Molles suggested that the “distribution of commonness and rarity” among species described by Preston is one of the best documented patterns in natural communities. This pattern has been quantified by many mathematical models. Since Motomura first put forward geometric series model to describe the feature of community structure, ecologists have developed many other models to fit the species-abundance data in communities or collections. These models can be classified into empirical and theoretical ones, including (1) statistical models, i.e., negative binomial distribution (and its extension), log-series distribution (and its extension), geometric distribution, lognormal distribution, Poisson-lognormal distribution, (2) niche models, i.e., geometric series, broken stick, overlapping niche, particulate niche, random assortment, dominance pre-emption, dominance decay, random fraction, weighted random fraction, composite niche, Zipf or Zipf-Mandelbrot model, and (3) dynamic models describing community dynamics and restrictive function of environment on community. These models have different characteristics and fit species-abundance data in various communities or collections. Among them, log-series distribution, lognormal distribution, geometric series, and broken stick model have been most widely used. Still, many questions remain unanswered, which include the selection of abundance indices, rules and mechanisms of spatial-temporal changes of species-abundance distribution, and selection, statistical test, ecological interpretation of various species-abundance relation models, and their uses in restoration ecology, conservation biology, and landscape ecology.