Wetland health assessment using DPSI framework: A case study in Kolkata Metropolitan Area

Abstract The wetland area has been threatening and degrading due to unplanned built up expansion, improper management of solid waste and sewerage water, waste water from agriculture and industrial sector, and siltation. The Kolkata Metropolitan Area is considered one of the most vital regions in terms of wetland ecosystem. Therefore, the aim of present research is to assess the factors responsible for wetland health and analyze their dynamicity by using the Driving force-Pressure-State-Impact (DPSI) framework. To assess the wetland health for the timeframe between 2011 and 2020, seventeen indicators and four sub indicators were selected to compute the weight through Analytic Hierarchy Process (AHP). The results manifested that most municipalities was in “healthy” category under pressure (P) part in 2011 while fluctuation were observed at multiple stations from 2011 to 2020 under impact (I) section. The state (S) part showed the overall transformation in water, vegetation and built-up class from 2011 to 2020. So the most dominating category was “healthy”, followed by “unhealthy” and “poor”. The highly significant factors that deteriorate the health of wetland were (B1) Population density, (B3) Road density, (B5) Per capita Sewerage generation, and (B7) Per capita solid waste generation, (D1a) BOD, (D1b) DO, (D1c) pH and (D1d) Total Coliform. The outcome of the research will contribute to develop for sustainable conservation and management of wetland ecosystem in urban area. Moreover could be applied at global level with similar geographical conditions.