The Potential of Integrated Constructed Wetlands (ICWs) to Enhance Macroinvertebrate Diversity in Agricultural Landscapes

Integrated Constructed Wetlands (ICWs) constitute an alternative option for the treatment of agricultural wastewater in Ireland. These surface flow systems are formed by interconnected ponds and have the capacity to fit into the landscape and provide habitat for a wide range of biota, including macroinvertebrates that have enormous potential for biodiversity enhancement. For these reasons, five ICW systems were studied. In addition, five natural ponds were investigated to account for the potential of ICW ponds to mimic natural conditions. Nine river sites were also investigated to allow for an evaluation of the catchment biodiversity contribution of the ICW systems. The present study revealed that the last ponds in the chain of these ICW systems are capable of supporting a similar number of taxa as natural ponds. Furthermore, the contribution of the last ponds to the macroinvertebrate diversity at the catchment level was high. ICWs seem to integrate their effluent management and purifying properties with that of biodiversity enhancement and landscape fit. This is the first study to investigate the potential of constructed interconnected ponds, used for wastewater treatment, to enhance biodiversity in agricultural landscapes.