<u>Ecological benefits and monitoring</u>

Ecological benefits and monitoring

Ecological shore structures and efficient dam restoration or elevation in one step.

Hybrid waters, as they arise in impounded rivers, often reveal similar problems. Because they are neither flowing waters nor standing water bodies, neither limnophilic nor rheophilic species can find suitable habitats. Only species that can survive almost everywhere can adapt here. On the up to now usual installed concrete slabs only very few species of flora and fauna can settle, a typical bank vegetation is completely missing. The contact with the surrounding land is related to the hydrology and the ecology interrupted to a great extent.

Oberelchingen KW LuftbildFolie1     Folie1

Figure 1 left: Storage space at the site Oberelchingen with existing dam (center), right: pilot line of the eco-berm at the site Offingen

In general, the project team therefore considers that the newly created environmental measures considerably improve the habitat in the storage space. Through the expected and desired development as a habitat for juvenile fish and selective enhancement of the biodiversity it is also assumed that the eco-berms own large-scale effects.   So they should not work only on the site itself, but also enhance the adjacent river or the alluvial forest ecologically.

Here the environmental measures allow to design habitats for different species. Gravel structures for gravel spawners or even dead wood structures can be built as a shelter for juvenile fish.

Generally, it is therefore planned to implement various ecological structures in small sub-regions on the test sections. The infrastructural measures as they were already explained in Section 2, always remain unchanged. In these sub-regions then the habitat shall initially be structured by different substrate. That means for example, that gravel is used in one area and in another area coarser stone-scrape is used. It is expected that these different habitats are settled in various ways. However, this thesis has to be validated during the project. As a next step, further measures, such as dead wood or groynes can be integrated.