Wetlands are areas lying along the banks of rivers and lakes and the coastal regions. They are life-supporting systems providing fish, forest products, water, flood control, erosion buffering, a plant gene pool, wildlife, recreation, and tourism areas. Though they are endowed with a rich biodiversity, yet of late they are being greatly exploited.
Many wetland species have become threatened and endangered because of their dependence on a particular type of wetland ecosystem, which has become seriously degraded or destroyed. Such is the case with the swampy grasslands and the flood plain wetlands of the Ganges and the Brahmaputra river valleys. Large areas here have been converted to agricultural land or there has been widespread overgrazing. Removal of sand, gravel, and other material from the beds of rivers and lakes has not only caused destruction to the wetlands but have led to sedimentation, which has affected other areas.
The introduction of exotic plants has had an adverse effect on these areas. The water hyacinth, a native of South America, is now a major pest in many areas forming a vast floating shield over the surface of the water and clogging up rivers and canals.
A number of factors have been responsible for the depletion of wetland areas mainly the mangrove forests, along the coasts of India. Intensive aquacultural development, deforestation, pollution from tankers, domestic waste, agricultural run off and industrial effluents are some of the factors. Most of the surviving mangroves are now confined to West Bengal and the islands in the Bay of Bengal.
The Ramsar Convention for the preservation of wetlands of international importance especially as Waterfowl habitat, was held in Iran in 1971. An Asian Ramsar group was thereafter formed in 1990 consisting of members who were a part of the Ramsar Convention.
In 1981, Chilika Lake, Indias largest brackish water lagoon, was designated a Ramsar Wetland of International Importance. But its fragile ecosystem has of late come under threat due to both anthropogenic and natural factors. It provides refuge to thousands of migratory birds and the balance in the ecosystem has to be maintained to ensure safe habitat for the birds.
For more information on the Wetlands link to