Impact of climate change on ecotopes of the rivers Rhine and Meuse.
Haasnoot, Marjolijn; Van der Molen, D. T.
Climate change, resulting in changes in temperature, precipitation, river discharge regime and sea level rise, may affect the ecosystems of the large rivers of the Netherlands in this century. This note discusses the method used to assess the impact of climate change on riparian ecosystems along the large rivers and presents the results of an application for the rivers Rhine and Meuse in the Netherlands. For this purpose, the effects of different climate change and land use scenarios on characteristic ecotopes have been compared with the current situation. The climate change scenarios were derived from the temperature rise estimation of the Intergovernmental Panel on Climate Change (IPCC). These have been translated into a sea level rise and changes in river discharge regime using results from earlier climate studies. Flood durations were derived by combining current contour maps of altitude and future sedimentation loads. For each type of ecotope a transition matrix has been developed to relate changes in flood duration and land use to changes in the types of ecotopes. The results indicate that climate change has a significant impact on several characteristic riverine ecotopes and therefore on the ecological quality of floodplains. However, the effect of natural land use is more dramatic and may therefore compensate for some of the negative effects of climate change.