PANAJI
Mangroves, which contribute to the rich marine eco-system of Goa, are “highly vulnerable” to anthropogenic litter pollution as a result of urban run-off, tourism and improper waste disposal. Plastic waste, including single-use plastic items currently banned in the State, accounts for over 66 per cent of the total litter impacting State’s mangrove recruitment, growth and survival, overall.
This was revealed in a recent study called “Anthropogenic litter pollution in the mangrove blue carbon ecosystem: Unveiling the spatial distribution, composition, source delineation and mitigation measures along the Goa coast” undertaken by scientist Nandan Das, Kalyan De, Amrita Sen and Bibekananda Maiti.
The study published in the Journal of Environmental Management in March concludes that litter pollution-induced mangrove degradation may directly impact the health of mangroves and related ecosystem functions.
The study examined seven mangrove habitats along the Goa coast - Diwar, Agassaim, Pomburpa, Querim – to evaluate anthropogenic litter levels and establish essential baseline data on environmental pollution in these ecosystems.
“The assessment of environmental quality and ecological risk indicates that Goa’s mangroves are highly vulnerable to litter pollution, with a significant presence of hazardous waste,” the study stated.
“Plastic items, particularly single-use plastics such as wrappers, bags, and bottles, dominate the overall litter composition. The majority of the litter originates from land-based sources, including urban run-off, tourism, and improper waste disposal,” it added.
The study revealed that 89 per cent of probable source of the litter was from land-driven sources while another 11 per cent from fishing-related activities.
Overall, plastic was the most significant litter type in all the surveyed mangroves, which contributed to an average 66.26 % of the total litter accumulation, followed by tetra packs of milk and beverages (9.12 %), glass items mostly liquor bottles (6.33 %), footwear (3.44 %), metal items (3.32 %), sanitary products including sanitary pad and diapers (2.49 %).
“Among the plastic litter, plastic fragments were most dominant, comprised of 23.36% of total plastic litter, followed by plastic wrapper (13.08 %), plastic bag (10.49 %), Styrofoam (9.51 %) and plastic bottle (6.84 %),” the study mentioned.
“Plastic sheets and bags may adversely affect the microorganisms that inhabit the roots of mangrove trees. Furthermore, as macroplastic litter degrade into microplastic, these small particles can infiltrate the food chain through marine organisms that live in these habitats. Many species, particularly the commercially significant fish and shellfish, ingest these plastic particles, and when humans consume seafood from contaminated ecosystems, they are exposed to harmful substances such as toxic additives and persistent organic pollutants associated with plastics,” it said.
Querim mangrove habitat recorded the highest plastic litter that is over 80 per cent, followed by Diver (72.4 %), and Agassaim (70.29%). Lowest plastic litter was recorded at Pomburpa (55.06 %).
“Our findings revealed a high accumulation of plastic litter in all the mangrove sites, supporting that mangrove vegetation acts as a natural barrier, trapping plastic and limiting its dispersal into the open ocean,” it said.
According to the researchers, administrators and policymakers need to develop timely strategies for effectively managing anthropogenic litter pollution and conserving ecologically important mangrove habitats. “Mangrove ecosystems in Goa exhibit a higher amount of entrapped litter, underscoring the need for targeted intervention, such as periodic clean-up drives,” they said.
