A detailed national inventory of wetlands has been prepared on the basis of satellite imagery by ISRO, highlighting areas of critical ecological significance and those which are facing extreme threat due to developmental activities.

This is for the first time in India that the city-based space application centre (SAC), a part of ISRO, has prepared such an inventory and atlas of all the wetlands that are existing in the country.

"Wetlands are the most productive ecosystems which play crucial role in hydrological cycle like helping in storm and flood control, water supply, providing food, fibre and raw materials and in recreational benefits," said SAC director Dr Ranganth R Navalgund.

They also support lakhs of migratory birds coming from colder regions of the world in summers, apart from diverse local flora and fauna.

"However, the very existence of these unique resources is under threat due to developmental activities and population pressure. This calls for long-term planning for preservation and conservation of these resources," Navalgund said.

"Creating an updated and accurate database that supports research and decision making is the first step towards this. SAC took up this challenging task under the project national wetland inventory and assessment (NWIA) sponsored by ministry of environment and forests," he said.

"Two-date, satellite data acquired during pre and post-monsoon seasons are used for inventory of wet and dry season hydrology of wetlands. They have been categorised in 19 classes and mapped following standard map projection. The map outputs include status of water spread, aquatic vegetation and turbidity," Navalgund said.