Hierarchical spatial patterns and drivers of change in benthic macro invertebrate communities in an intermittent Mediterranean river.

1. The imminent damming of the Odelouca River, an intermittent Mediterranean river situated in the south-west Algarve region of Portugal with valuable stands of riparian vegetation, has called for the compulsory implementation of compensatory measures. 2. In order to assess the primary environmental and human factors that drive change in the benthic macroinvertebrate assemblages of the Odelouca, and the spatial scale at which they occur, 30 sites were sampled for benthic macroinvertebrates and extensively surveyed.