The Convention on Wetlands of international importance (Ramsar) defined wetlands as: "areas of marsh, fen, peatland or water whether natural or artificial, permanent, or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres." Natural or artificial marshes, stagnant lakes and ponds, mangroves, swamps, coral reefs and estuarine waters - all form wetlands. These are one of the most productive and naturally endowed systems on earth. These are also some of the most endangered ecosystems. 58.2 million hectares comprise wetlands in India.
The mangroves in India have reduced by half in the last 10 years. Further, 70 to 80 per cent of fresh water marshes and lakes in the Gangetic plains have been lost in the last 50 years.Several human activities threaten wetlands - agriculture, provision of irrigation systems, reallocation of land for urban and forest use. Construction of transport systems and pollution from boats, sewage, pesticides, fertilisers and industrial effluents are some of the major problems.
India has signed the Ramsar Convention on Wetlands and the Convention of Biological Diversity. Legislative measures are abundant, but conservation and management programs must now be implemented.