Influence of Detritus on the Structure of the Invertebrate Community in a Small Portuguese Stream

Abstract

This study tests if the coarse particulate organic matter (CPOM) mass was related to the invertebrate community structure in riffles and sandy pools of a fourth-order reach of a stream after partialling out the effects of physical characteristics of the sampled patches. Diversity and structure of the assemblages differed between habitats. In both, CPOM mass was positively correlated with total density and with all functional feeding groups excepting filterers. Redundancy analyses and variance partitioning procedures indicated that (1) CPOM stocks influenced the assemblage structure in both habitats, and (2) most of those effects were unrelated to sampling date and measured physical characteristics (water depth in sandy pools, Froude number and substrate composition in riffles) of the patches. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)