You are here:
A cross-continental comparison of the effects of flow intermittence on benthic invertebrate assemblages
Citation:
Datry, T., D. Arscott, M. Bogan, K. M. FRITZ, S. Larned, A. Santos, AND P. Wood. A cross-continental comparison of the effects of flow intermittence on benthic invertebrate assemblages. Presented at Society for Freshwater Science, Louisville, KY, May 20 - 24, 2012.
Impact/Purpose:
The goal of this research is to develop methods and indicators that are useful for evaluating the condition of aquatic communities, for assessing the restoration of aquatic communities in response to mitigation and best management practices, and for determining the exposure of aquatic communities to different classes of stressors (i.e., pesticides, sedimentation, habitat alteration).
Description:
Although temporary rivers are widespread freshwater systems, they have been poorly studied by ecologists and are largely ignored in water management plans, practices and policies. If the effects of dry events on benthic invertebrates have been reported individually from different rivers across the world, the comparison of these effects among contrasted river systems has never been made and is yet required to assess their generalities. In this meta-analysis study, we compared the effects of flow intermittence on invertebrates from 11 different rivers located in different biomes and showing contrasted spatial drying patterns. Particularly, we examined the quantitative relationships between flow permanence, dry event duration and frequency, and invertebrate taxonomic richness, density and % EPT taxa; and the nestedness of invertebrate communities along flow intermittence gradients. The first results indicate some important generalities in the responses of invertebrates to river drying. Notably, a 10% flow permanence decrease resulted consistently in all rivers in the removal of taxa from communities. Additionally, in most rivers, taxa from temporary sites were nested subsets of communities from perennial sites and no specialist-taxa was identified. These results have strong ecological meanings and present promising management implications.