Patterns of distribution of annelids: Taxonomic and spatial inconsistencies between two biogeographic provinces and across multiple spatial scales

Abstract

Issues of scale and taxonomic resolution are of fundamental importance to studies of biodiversity. To aid in measuring distributions cost-effectively, it has been widely proposed that different levels of taxonomic resolution should be used, depending on the scale of the ecological process or environmental impact being investigated. The effect of taxonomic resolution on patterns of difference in natural spatial variation and abundance of annelids associated with reefs of Sabellaria alveolate was therefore investigated in 2 different biogeographic provinces (Wales and Portugal) over scales of centimetres to 10s of kilometres to identify generality in patterns over different spatial scales and levels of taxonomic resolution. In Wales, there appeared to be some support for the model, with the amounts of small-scale variability increasing with increasing taxonomic resolution. In Portugal there was, however, no relationship between taxonomic resolution and spatial scale. Spatial patterns of annelids grouped at differing taxonomic levels were not consistent between the 2 biogeographic provinces. Any models proposed to explain variation in these patterns must account for differences in patterns among taxa within biogeographic provinces and for the same taxa between biogeographic provinces. This will make such models much more complex than many that have been traditionally proposed to explain spatial variability at different scales. © Inter-Research 2007.