Rivers in warm ecoregions - overview
The pristine status
Mediterranean regions are dominated by warm to hot, dry summers and mild to cool, wet winters in winter, watercourses located at these regions are characterized by predictable seasonal disturbance events. The species are adapted correspondingly, with many insects having a diapause in the terrestrial adult stage. Mediterranean rivers belong to the most species rich aquatic ecosystems in Europe, with many endemic species which are often restricted to a single mountain range.
Besides organic pollution and eutrophication the main human impact is water abstraction, which prolongs the period of low (or no) flow. Particularly water use for irrigation purposes has lead to the almost complete disappearance of small streams from many regions.
Climate change impact
The mediterranean region is among the most vulnerable ecosystems to the effects of climate change. Climate change and consequent changes in hydrology are projected to lead to unpredictable harsh events, exacerbate water stress and desertification, and turn landscapes more desert-like. Such changes are expected to affect freshwater biota, despite organisms being adapted to withstand the typical natural disturbances (i.e. resistance ability) and to recover rapidly from those disturbances (i.e. resilience ability).
For further reading
- Filipe AF, Lawrence JE, Bonada N (2012) Vulnerability of stream biota to climate change in mediterranean climate regions: a synthesis of ecological responses and conservation challenges. Hydrobiologia. link to article
- Erol A, Randhir TO (2012) Climatic change impacts on the ecohydrology of Mediterranean watersheds. Climatic Change, 114, 319–341. link to article