The degradation of peri-urban wetlands has been a significant consequence of urban development and climate change. The present study discovered the decadal changes in land cover and climate impact on Raja Wetland, revealing significant alterations from 2011 to 2021. The analysis indicates substantial reductions in agricultural land (36.36%), fallow land (30.90%), water spread areas (10.14%) and surrounding wetlands (18.06%). Conversely, settlements, terrestrial vegetation and aquatic macrophytes increased by 19.77%, 3.39% and 1.16%, respectively. The primary driver of wetland shrinkage was urban expansion leading to a decrease in wetland area from 43.39 ha in 2011 to 38.99 ha in 2021. Climate data from 1991 to 2020 show a decreasing trend in annual rainfall (τ = - 0.274, p = 0.035) and an increasing trend in annual temperature (τ = 0.339, p = 0.009), with significant warming particularly during the monsoon months. The wetland's physicochemical attributes fluctuate seasonally, with eutrophic conditions prevailing (TSI range: 61.41-80.36). Notably, fish diversity is impacted by the dominance of the invasive species Oreochromis niloticus, which constitutes 89.31% of the catch. The established planktonic indicator genera of organic pollution were found to be abundant throughout the study period. These, combined with urban pollution and eutrophication, have led to a reduction in native fish species and overall aquatic health. The study highlights the urgent need for conservation measures to address the ecological imbalance and restore wetland resilience amidst ongoing climate and anthropogenic pressures. The communication also proposes various recommendations for the recovery and sustainable future use of wetland fisheries in the context of ongoing changes.
Keywords: Climate change; Fish; LULC; Phytoplankton; TSI; Urbanization.
© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.