The study was based on data collected over 30 years in various river ecosystems in Europe. More than 26,600 samples were analyzed and the intention was to analyze whether, over the last decades, there has effectively been a recovery of aquatic biodiversity in river systems, as a consequence of the mitigation measures implemented in Europe.
Maria João Feio and Manuel Graça, from the Center for Marine and Environmental Sciences (MARE) of the Faculty of the University of Coimbra, were two of the researchers among many from across the European scientific community who used aquatic invertebrates as bioindicators of the ecological quality of rivers. They concluded that, despite positive trends in the 1990s, since 2010 the recovery of river biodiversity has stalled. In the 90s, improvements were due to “greater treatment of sewage, industrial but also urban effluents and this led to an improvement in the conditions of European rivers, which, in some cases, were in quite dramatic conditions” , highlights Maria João Feio. .
Although projects to combat river degradation have continued, the number of species in some places has decreased by 30%. And starting in 2010 the situation worsened.
“There have been a number of new impacts on rivers, which are pollutants such as pharmaceuticals, new industrial pollutants, microplastics and new invasive species,” he adds. The number of non-native species increases by 4% per year. Furthermore, biodiversity recovery has stalled or retreated even in places with higher temperatures, a sign that climate change is damaging rivers.
The riparian ecosystems where there was the least recovery were those located downstream of the dams, in urban areas and agricultural lands.
This research, in which 96 European researchers from 70 institutions participated, was coordinated by researchers from the Senckenberg Research Institute and the Natural History Museum in Frankfurt, Germany.
Source: TSF
