Riverine floodplains - Renaturation and its importance as a CO2 sink: Floodplains, the natural areas that occur along every river and can be flooded by high water, have been largely destroyed by human activities in Germany. Only 30%, on large rivers such as the Rhine and Elbe only 20%, are available for the natural alternation of high and low water. And this despite the fact that intact floodplains have a high biological diversity, improve water quality, offer natural flood protection, serve the recreational function for people and as CO2 sinks for climate protection. Possibilities are shown how CO2 reduction can be achieved through floodplain restoration.