Species-environment relationship in marine soft-bottom communities: regression modeling and the implications of scale

A literature study was performed aiming to explore the relation between the spatial scale of marine benthic surveys and the observed goodness-of-fit of regression models relating animal abundance to the environment. A further objective was to tabulate the abiotic factors and processes that predominantly explain the variation in abundance and to examine whether or not the type of important factors differ in relation to the scale of the study. Single studies in which benthos-environment regression models were applied at different spatial scales and which would have allowed a within-study comparison of the goodness-of-fit in relation to scale, were not found. The paucity of studies that reported quantitative information and, if they did so, the use of a variety of incomparable statistical models resulted in very few observations and a lack of statistical power of the (between-study) relation between scale and goodness-of-fit. Most studies confirmed the importance of sediment characteristics and elevation (in case of intertidal areas) or water depth (in case of subtidal areas) in determining the benthos. Further studies on the importance of the spatial scale of marine benthos-environment surveys should be based on a unified analytical approach, which can only be realized if original data are available.