Seine Aval in France and its macroinvertebrates

The Seine Aval is the stretch of the Seine from the Dam of Poses upstream of Rouan to Vieux Port 125 km downstream. In coorparation with Ecoconsult and Waterfauna we investigated the macroinvertebrates in the freshwater tidal part of the Seine Aval.

In the table the molluscs are shown for the three ecological stretches of the Seine Aval. The upper part upstreams of Rouan (km. 203-230), the vicinity of Rouan with serious pollution (km. 247 – 288) and the downstream section (km. 292-324) with poor waterquality, a massive load of suspended solids and little or no suitable habitat for invertebrates.

Upstream of Rouan 26 species were encountered, In the area polluted by Rouan wastewater 16 species were found. In the downstream section only 4 species managed to survive on the mudbanks or in the tidal sands.