Riverine wetlands provide a range of ecosystem services: cultural (aesthetics, recreation and education); provisioning (storage and retention of water); supporting (soil formation and nutrient cycling) and regulating (regulation of erosion, natural hazards, hydrological flows, climate, water purification and waste treatment).
CLEARANCE focuses on the role of wetland buffer zones (WBZ) in agricultural catchments. They clean the water from the excess of nutrients before it reaches the river, contributing also substantially to the natural purification of river water. To demonstrate this role of WBZs, it will use model catchments and examine synergies between water purification and other ecosystem services.
The project aims to enhance multifunctional use of riverine wetlands via circular economy, where nutrients captured in wetland biomass are re-used to produce energy (via combustion, biogas or pyrolysis), materials or soil substrates (compost), while at the same time reducing greenhouse gas emissions via rewetting of drained organic soils and re-establishment of peat formation. Last but not least, riparian biodiversity and recreational functions of riverine wetlands are treated as co-benefits of the above-listed services, altogether allowing for a multi-faceted evaluation of WBZs and developing an integrated framework - socio-economic, environmental and political - for the implementation of WBZs in circular economy.
The project allowed to quantify the effectiveness of wetland buffer zones. Further, using a multidisciplinary approach we were able to delineate potentially restorable WBZs in three model catchments (in Poland, Germany and Denmark) and carried out an extended cost-benefit analysis for one case catchment (lower Narew river, Poland) revealing high cost-effectiveness of WBZ re-establishment. To analyse how WBZ re-establishment can be combined with wet agriculture, potentially harvestable plants were screened for their nutrient uptake. In addition, a field study on the impact of mowing on nutrient retention carried out in a small Polish brook found that, while mowing can enhance nutrient removal by biomass expert, it also lowers the residence time of nutrients due to modification of plant biomass quality, whereas a study in Danish (restored) and Polish (natural) WBZs allowed to quantify possible nutrient removal with hay in spontaneously established vegetation.
The economical choice experiment, involving 3000 participants in three Baltic Sea basin countries, revealed overwhelming support of people for restoration of riverine landscapes with a primary focus on improving water quality. A series of workshops allowed to identify main barriers and opportunities for the re-establishment of WBZs, and develop recommendations for EU policy amendments.
*At the time of the proposal. Please consider this data as an accurate estimate; it may vary during the project’s lifespan.
Total costs include in kind contribution by grant holders and can therefore be higher than the total requested funding.