Floodplains and coastal wetlands as nutrient sinks: a restoration perspective

Floodplains and coastal wetlands provide essential ecosystem services such as flood protection, water quality enhancement, carbon sequestration, and the production of raw materials and food. Despite numerous studies on wetland restoration, the complexities of restoring ecosystem functions remain challenging. Complete restoration of natural functions is rare, and therefore seldom the primary target; instead, restoration efforts typically focus on reactivating key ecological processes. This study examines the restoration of ecosystem functions in floodplains and coastal wetlands, focusing on water quality improvement. It summarizes both nitrogen and phosphorus dynamics, highlighting the potential to restore processes like denitrification and sedimentation within relatively short time frames using selected case studies from Central Europe. However, restoration success is hindered by altered soil properties, nutrient legacy, and other degradation-related constraints. Ultimately, the effectiveness of restoration endeavors depends on site-specific factors such as wetland degradation, size, hydrological connectivity, plant recovery, and ongoing global changes. This underscores the importance of considering both spatial and temporal dimensions and adopting a custom-tailored restoration strategy. Highlights Recovery of nutrient retention processes can be either rapid or delayed Nutrient legacies and soil degradation hinder ecosystem restoration. Process insights and site traits guide effective restoration efforts.