Introduction to Wetland Ecosystem Degradation

Wetland ecosystems play a crucial role in maintaining ecological balance, supporting biodiversity, and providing essential ecosystem services such as water filtration, carbon sequestration, and flood control. However, these ecosystems are facing severe degradation due to multiple anthropogenic and natural drivers. In India, wetlands are particularly vulnerable due to rapid urbanization, industrialization, and changing climatic patterns. Among the many factors contributing to wetland degradation, two major drivers stand out: land-use change and pollution.

1. Land-Use Change and Encroachment

Land-use change is a primary driver of wetland degradation in India. It includes urban expansion, agricultural intensification, and infrastructure development, leading to significant alterations in wetland structure and function. The encroachment of wetlands is particularly prominent in rapidly urbanizing regions where wetlands are drained or filled for construction and other developmental purposes.

Urban Expansion and Infrastructure Development

Urbanization exerts immense pressure on wetlands, leading to their fragmentation, shrinkage, and destruction. India’s expanding cities, such as Delhi, Mumbai, and Kolkata, have witnessed large-scale encroachment of wetlands to accommodate rising populations and infrastructure demands. Many urban wetlands, which once served as natural flood buffers and groundwater recharge zones, have been converted into residential, commercial, and industrial areas.

For example, the East Kolkata Wetlands, a Ramsar site, have been significantly encroached upon due to illegal construction activities. Despite legal protections, urban expansion continues to threaten their existence, reducing their ability to act as natural sewage treatment systems and fish breeding grounds.

Agricultural Expansion and Intensification

Agricultural land expansion has been another major cause of wetland degradation in India. Many wetlands are drained and converted into croplands, leading to loss of wetland hydrology and biodiversity. Paddy fields, which replace natural wetlands, alter the hydrological cycle and contribute to soil degradation. Over-extraction of groundwater for irrigation purposes further exacerbates wetland loss by lowering the water table.

For instance, in Punjab and Haryana, extensive groundwater extraction for irrigation has resulted in the drying up of seasonal wetlands. The Kolleru Lake in Andhra