Sustainability Challenges of Astamudi Brackish Wetland - A Ramsar Site
DOI:
https://doi.org/10.55863/ijees.2025.0416Keywords:
Conservation concerns, Habitat degradation, Estuarine ecosystem, LULC change, Biodiversity, Conservation measuresAbstract
This study analyses the sustainability challenges faced by Ashtamudi wetland (an estuarian ecosystem and a Ramsar Site of international importance viz., habitat degradation, soil loss and sediment export, unsustainable tourism, littoral drift, saline intrusion, overfishing, human encroachment, pollution, and violation of coastal regulatory norms faced by Ashtamudi wetland, an estuarine ecosystem and a Ramsar Site of international importance. Between 1980 and 2023, the wetland's water spread area and volume decreased by 27 and 46.30 %, respectively, with maximum depth observed near Kanjirottu Creek. Direct precipitation over the Ashtamudi wetland was reduced by 37.46 %, and the changes in land use patterns in the watershed area of the wetland demonstrated that settlements with vegetation increased by 46.55 %. In comparison, dense vegetation decreased by 34.67 %. Quantifying nutrients in the sediments of Ashtamudi wetland in 2024 demonstrated a maximum potassium and phosphorus concentration of 448 and 63 kg/ha, respectively. Heavy metals, viz. Fe, Cu, Cr, and Pb were present in the sediments of the Ashtamudi wetland, and this could be due to industrial and urban growth near the shoreline. Discharge from the Kallada River decreased by 33.08%, leading to shoal and bar formation near the Neendakara estuary, necessitating periodic dredging for the port operations. Salinity influx in the year 2024 ranged from 22.58 to 47.87 ppt from the inlet to the wetland outlet. This wetland supports a variety of flora and fauna, including 52 varieties of phytoplankton, 97 species of fish, and 116 species of birds. The Total Economic Value (TEV) of Ecosystem Services provided by Ashtamudi wetland in 2020 was estimated at $ 424,873,525. All the above issues suggest the need to devise a sustainable action plan to maintain the ecological balance of this brackish wetland system.
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