Spatial and Temporal Variation of Benthic Metacommunities in Alpine Streams

How do rivers work? How are aquatic species distributed in the river network?

Several theories have been proposed throughout the history of river ecology to explain how community composition changes along the river course in response to the gradual shifts of environmental and trophic conditions. Among these, the River Continuum Concept (Vannote et al., 1980) is certainly the most well-known. However, in recent years, there has been a growing awareness that rivers are dendritic systems, not simply reducible to a linear upstream-downstream path. This raises questions on how tributaries and specific locations within the river network can influence biodiversity and the ecological processes occurring in these ecosystems.

The research project “Network Po” aimed at answering these questions. Twelve sampling sites were selected within the Po River’s network (in detail six central and six peripheral), spanning the municipalities of Crissolo, Ostana, Paesana, and Sanfront. Three sampling campaigns were conducted in April, July, and November 2021. The results of this project will enhance our current conceptual and regional understanding of the taxonomic and functional organization of benthic river communities (macroinvertebrates and diatoms) at river network scales.