The habitat volumes of scarce and ubiquitous plants: a test of the model of environmental control

Abstract

Examined the expected relationship between the ubiquity of species in samples and the realized edaphic habitat volumes of these species. The habitat space of a suite of plants from southern Western Australia was defined by principal-components analysis of soil data. The habitat volumes of 36 scarce and 41 ubiquitous species were not significantly different. An alternative hypothesis is suggested, that scarce plants do not have restricted environmental tolerances but, rather, fill their habitat space more sparsely. Strong correlations between species frequencies in samples and habitat volume were observed in the total data set and in 8 of 10 plant guilds, corroborating predictions, but only h..