Wetlandscape size thresholds for multiple ecosystem service delivery

Wetlands are increasingly considered as nature based solution as they provide valuable services and functions to the society and environment, such as water quality improvement and biodiversity support. However, while land use and climate change have been affecting the functions and service of these ecosystems, it has become important to study the large-scale behaviour of wetlands in the landscape. Consequently, previous studies have suggested to study wetlands within wetlandscapes, defined as catchments containing networks of several wetlands, in order to understand large-scale functions of wetlands and their response to land-use and climate changes. This emphasizes the ecohydrological interactions of wetlands rather than having focus of individual wetlands. However, as the concept of wetlandscape is new, its governing properties have not yet been systematically quantified.

In this paper, we quantify ecohydrological properties of individual wetlands in multiple wetlandscapes, typical for northern Europe, that may impact biodiversity and modulate nutrient flows (e.g. wetland area, wetland catchment area and wetland type) as well as characteristics of the whole wetlandscape in terms of their large-scale processes and functions. We also investigate possible systematic differences between wetlandscapes of different size. Results show that large wetlandscapes generally contained features to support different ecosystem services compare to smaller wetlandscapes. More specifically, results indicated that small wetlandscapes have a poor ability to route water through their wetlands (i.e. catch flow from the entire wetlandscape) which was in contrast to large wetlandscapes. This implies that large wetlandscapes have a higher potential for large-scale retention of nutrients and contaminants. Present result support the importance of wetlandscape studies and the priority of a wetlandscape focus in future management programs for instance targeting regions with large-scale pollution issues.