In north-western Germany, inland dunes and natural floodplains were widespread in the past. Due to the regulation of the natural course, large rivers have experienced serious anthropogenic influences resulting in a decline of adjacent natural floodplains. The realization of a restoration project in north-western Germany had the aim to restore a floodplain composed of inland dunes and seasonally flooded grasslands. Within this project, the response of wild bee communities to such restoration measures was evaluated. Therefore, an analysis of the succession and distribution patterns of wild bee communities in restored and target habitats was conducted. In chapter 1 and 2 the success of the restoration measures was evaluated by a comparative analysis of wild bee communities at restoration and target sites. The results show a rapid colonization of a species-rich wild bee community reflecting a community composition which is composed of generalists, specialists and parasitic species. The quantity of entomophilous plant species and the proportion of bare ground had a strong influence on wild bee species composition. To gain insight into the connectivity of wild bee populations, the population genetic structure of two wild bee species, Andrena vaga and Andrena fuscipes was analysed in chapter 3 and 4. Additionally, general intrinsic factors that maintain the genetic diversity and influence the degree of inbreeding were evaluated in chapter 5 on the basis of an extensive literature survey. These results reflect a high dispersal ability and inter-population movement of wild bees. For both species a high genetic diversity within populations and a low genetic differentiation among populations was found. In conclusion, wild bees proved to be useful indicators for monitoring the effects of restoration projects. The combination of population genetic analyses and community monitoring provides the opportunity to evaluate different aspects of restoration success.