Defining floodplain boundaries considering hydraulic and ecologic aspects as basis for the development of an integrated approach to quantify ecosystem services of floodplains on the landscape scale

• Applicant: Dr. Stephanie Natho
• Subject Area: Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 390612937

The aim of the proposed project is the development of a mesoscale approach to quantify ecosystem services of floodplains. Hydraulic and ecological aspects are considered to define limits of interaction and thus floodplain extents and their functioning regarding the provision of ecosystem services which are fundamental for human well-being.Although the ecological importance and major endangerment of floodplains are known and acknowledged worldwide, measures are still taken which deteriorate the status of floodplains and services in an unknown dimension. The reason for that is the limited understanding of interactions between floodplain status, anthropogenic measures, natural processes and ecosystem services. The latter of these services is neglected when calculating costs for measures because an integrated approach to evaluate these services is missing on the relevant scale, the landscape scale.The deficits in research on ecosystem services are the use of various wordings and not consistent definitions as well as different scales and indicators. Existing approaches are based on either a small scale and are too complex or on the global scale and are too simple to transfer them to landscape scale. Global approaches already fail regarding the floodplain extent as a spatial basis. A transferable method is developed that allows a comprehensive application of the ecosystem service concept including nine ecosystem services: hydrological, water quality and climate services, biodiversity, food, construction and energetic material production, protection from natural hazards and cultural heritage. The hydraulically derived inundation areas of frequent floods provided by publicly available flood hazard maps serve as a spatial basis. For the first time, the suitability of these maps is analyzed by means of comprehensive vegetation and ground beetle data sets provided by research institutes namely the German Federal Institute of Hydrology and the University Duisburg-Essen. New indicators for each of the nine ecosystem services are developed basing on geodatasets and literature research. By Meta-Analysis, the transferability of existing economic proxies is reviewed. These values will then be included into the economic evaluation of ecosystem services which finally leads to a calculation of the economic value of floodplains on landscape scale. As a result, floodplains and their conservation, protection and restoration can be considered in a substantial way. Considering ten already carried out floodplain restoration projects this approach is validated using a cost-efficiency-approach.This new integrated approach is interdisciplinary to meet the challenges resulting from the complexity of floodplains and their provided services on the landscape scale. By valuating ecosystem services various links to other disciplines are provided. Finally, amongst others, biologists, hydrologists, geoscientists and economists receive a unified databasis.

• DFG Programme: Research Grants