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

Abstract

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.

A review of the potential of surface flow constructed wetlands to enhance macroinvertebrate diversity in agricultural landscapes with particular reference to Integrated Constructed Wetlands (ICWs)

“…In this respect, Becerra-Jurado et al (2010) showed that permanent ICW ponds (around 5 years old) showed no significant seasonal differences (spring vs. summer) in coleopteran community structure, indicating low species turnover (lost and new pond species). In contrast, temporary ponds may act as sink habitats for taxa from permanent ponds via seasonal influx of aerial colonizers (Nilsson & Svensson, 1994).…”

“…Amongst the biota present in surface flow constructed wetlands, birds have yielded the most extensive data series (Knight et al, 2001;Benyamine et al, 2002, Hansson et al, 2005, although macroinvertebrates have been a group also targeted in most of these biodiversity studies (Spieles & Mitsch, 2000;Knight et al, 2001;Hansson et al, 2005;Becerra-Jurado et al, 2010;Boets et al, 2011).…”

“…Significant differences have also been found in terms of taxon richness and community structure along the treatment process of surface flow systems including ICWs (e.g. Spieles & Mitsch, 2000;Becerra-Jurado et al, 2010;Boets et al, 2011). Spieles & Mitsch (2000), working on high-and low-nutrient surface flow constructed wetlands, showed comparatively higher Invertebrate Community Index scores at the middle and outflow areas, compared to areas near the inflow, and differing macroinvertebrate community structures along the treatment process.…”

“…Whilst Coleoptera larvae (mostly Helodidae) and Psychodidae (Diptera) were mostly found in the first ICW ponds, Cloeon dipterum (Ephemeroptera), Coenagrionidae (Odonata) and Pisidium/Sphaerium spp. (Mollusca) were more abundant in the last ICW ponds (Becerra-Jurado et al, 2010). In addition, Hemiptera were generally found in the last ICW ponds (BecerraJurado et al, 2008).…”

Ecological Drivers of Cladoceran Diversity in the Central European City (Łódź, Poland): Effects of Urbanisation and Size of the Waterbody

“…Integrated Constructed Wetlands (ICW) are man-made wetlands (a series of interconnected ponds containing emergent and submerged plants) built to treat agricultural wastewater (Becerra-Jurado et al, 2010). They can ensure that ponds remain in agricultural landscapes and have been recorded to contribute significantly to freshwater biodiversity; total macroinvertebrate diversity in the last ponds of an ICW series (116 taxa) in Ireland was comparable to total diversity in natural ponds (129 taxa), although the ICW pond at the beginning of the series supported limited invertebrate biodiversity compared to the others (Becerra-Jurado et al, 2010).…”