Evaluating the Applicability of Phytoplankton Community Indices in Assessing The Ecological Quality Status (EcoQS) of a Coastal Ecosystem (Thane Creek, India): Mono-Metric vs Multi-Metric Approach

The ecological quality status (EcoQS) of Thane Creek which is surrounded by a highly urbanized and industrialized sector of Mumbai was assessed by considering six phytoplankton community indices. Sampling was carried during Premonsoon to compare the efficiency of selected indices (Chl a, abundance, H′, MDI, IPI and MMPI) in the tropical setting. Ecostatus proposed by selected phytoplankton indices assigned a 'moderate-good' status to phytoplankton zone (PZ)-I, 'moderate-poor' to PZ-II while 'bad' to PZ-III. Comparatively, MMPI appeared to be the most efficient water quality index because of its capability in discriminating between 'acceptable' and 'not-acceptable' EcoQS. The gradient of anthropic activities along the creek plays a major role in deciding the EcoQS of Thane Creek. Limitations of all indices in evaluating environmental quality were also discussed in the present study. The investigation could provide a fillip to policymakers who are undertaking coastal water quality improvement initiatives.