Challenges in assessing ecological impacts of construction and demolition waste on wetlands: a case study

Abstract

Although wetlands are of ecological and economic importance, they continue to be lost to anthropogenic activities such as infilling. The impacts of wetland infilling with construction and demolition (C&D) waste on wetland plant and dipteran (Insecta: Diptera) communities were examined. Areas of wetland infilled with C&D waste compared to non-infilled areas had: a) higher soil pH and lower soil moisture / organic content; b) a relatively higher percentage of ruderal plant communities; c) relatively fewer dipteran families that were wetland specialist, gall-forming, parasitic and haematophagous; d) relatively lower abundances and species richness of marsh flies (Diptera: Sciomyzidae). Challenges encountered during this study included locating C&D waste sites; obtaining permission from landowners to undertake this study; frequent damage and theft of equipment due to human interference, machinery and infilling activity. Given the current paucity of data regarding the ecological impacts of infilling with C&D waste on wetlands and the considerable challenges with undertaking such studies, we make recommendations for appropriate site selection and monitoring at C&D waste infill sites.