Spatiotemporal microplastic occurrence study of Harike wetland, A Ramsar wetland of India

Abstract

Ramsar wetlands are one of the least investigated areas for microplastic contamination. Harike wetland is located downstream of the confluence of the Beas and Sutlej rivers. Rivers are nature's drainage systems, which collect waste from everywhere and move ahead. On the same note, the Harike wetland, the largest wetland in North India, is an ideal home for migratory birds and aquatic animals. The water in the canal and the fish living within it have been examined for microplastics. Results revealed that the number of microplastics did not significantly differ between sites 1 and 2, but showed a seasonal variation with higher levels observed in the winter season compared to summer and the rainy season. The most common types of plastics detected in the wetland and canal were HDPE and nylon, which were further analyzed using conformational tests, ATR-FTIR, and GC-MS techniques. Additionally, microplastics measuring less than 5mm in size were recovered from the gut of Cyprinus carpio fish, with a 7% recovery rate from the total number of fish analyzed. Although this percentage may seem low, it cannot be ignored given the potential impact on the aquatic environment. This percentage may be less, but it is not ignorable. Indeed, the amount of poorly managed plastic garbage generated by people living around or illegal outskirts garbage dumping near rivers and tributaries is a potential source of aquatic debris.