Inadequate management of non-degradable litter in coastal areas can lead to its accumulation in mangrove forest, affecting its ecosystem services. Abundance and distribution of marine litter and its impact on benthic organisms in mangrove ecosystems are far less investigated in India. Thirteen mangrove ecosystems distributed in Ernakulum District, Kerala were selected for the study and evaluated for plastic pollution. The identified litter particles were categorized according to particle type, colour, size and composition. The abundance of plastics estimated was classified according to its source of origin. The abundance of benthic organism in the study stations was also estimated. The density of micro (<5 mm) and meso (5-25 mm) plastics ranged between 29 and 36 Nos/kg with the highest concentration found in mangrove sediments of Kumbalangi and the lowest in protected area like Mangalavanam. Plastics accounted 73 to 96% of total macro litter. The major polymer types identified were polyethylene, polypropylene, polyethylene terephthalate and polyvinyl chloride by Fourier Transform Infrared (ATR–FTIR) spectroscopy. The simulation experiment showed a progressive reduction in total benthic community when smothered with thick plastic sheets. This study is an eye opener concerning plastic litter problem in mangroves of the Vembanad Lake ecosystem, which can be well explained as due to anthropogenic impact.

Assessment, non degradable litter, impact, anthropogenic, benthic community