Invertebrate Communities and Environmental Conditions in a Series of Urban Drainage Ponds in Eastern Scotland: Implications for Biodiversity and Conservation Value of SUDS

Increasing use is being made of constructed wetlands to store and treat urban drainage prior to release into watercourses. Known as sustainable urban drainage systems (SUDS) in the UK these have potential to support and enhance freshwater biodiversity in urban areas, but the diversity and value of communities present in these ponds is not well established. This study establishes the characteristics of invertebrate communities and investigates links with prevailing environmental conditions in four SUDS sites in Dunfermline, Scotland over a five year period. The SUDS ponds supported communities of between 10 and 47 invertebrate species. Only one beetle species of conservation significance was recorded, along with an invasive species of mollusc. There were significant temporal changes in species richness and community composition, with the sites losing species and becoming more dissimilar over time. Variation in the invertebrate species composition at the sites was linked to both average environmental conditions and temporal variability, particularly soluble reactive phosphorus and dissolved oxygen levels. The biodiversity value SUDS of invertebrate communities may be limited by pollutant loads being received from drainage, but they can still potentially contribute to freshwater diversity in urban areas. In order to maximize their biodiversity potential, more research needs to be undertaken on appropriate design and management considerations.