Coastal and deep-sea benthic diversities compared

Abstract

Most generalisations about marine benthic diversity (species richness) are derived from few studies, few samples and low specles numbers. It is questionable whether the data on whlch most parad~gms, espec~ally about the deep sea, are based truly represent general patterns of marine diversity. Available information from deep-sea studies are summarised and compared with some extensive data sets from the shallow coasts of Norway and Australia. We show that species richness per unit area is as hlgh, if not higher in shallow sedimentary habitats a s was reported for the deep-sea data by Grassle & Maciolek (1992; Am Nat 139 313-341). Apparent high diversity in the deep sea may be explained, In part, by the vast area of this environment. All surveys in both the deep-sea and coastal habitats are shown to traverse a variety of microhabitats and thus sediment heterogeneity is not a n explanation for the high species richness in coastal environments.