India’s ‘National Wetland Decadal Change Atlas’ was released on World Wetlands Day 2022 on 2 February. Formally named as ‘Space-Based Observation of Indian Wetlands’, the Atlas is documentation of wetlands across India, especially regarding the changes from 2006-07 till 2017-18.

According to the updated Wetlands Atlas, there has been an addition of 14,823 new wetlands with an area of 0.36 million hectares (Mha) between 2006-07 and 2017-18, while a total of 1342 wetlands covering an area of 0.025 Mha have disappeared.

India has the largest land area among the eight south Asian countries. It is home to 757,000 wetlands with a total wetland area of 15.3 Mha, accounting for nearly 4.7% of the total geographical area of the country. However, around 340 wetlands have ‘disappeared’ between 2007 and 2018, according to the Atlas. Natural wetlands saw losses in area while human-made ones increased.

In absolute numbers, there has been a total increase of 0.64 Mha area and 18,810 wetlands. The increase in wetland area includes both new (56.4%) as well as positive change in the existing wetlands (43.6%). Among the wetlands that disappeared in the 2017-18 document, are mostly waterlogged regions (natural and human-made), tanks in abandoned mining, and aquaculture ponds.

Tamil Nadu (11.6%) and Maharashtra (11.2%) have got a high number of wetlands. In contrast, the Ganga river basin has around one-fourth of the wetlands in both numbers (over 56,000) and wetland area (3.75 million hectares (Mha) among the river basins of the country. After Tamil Nadu and Maharashtra, it is Andhra Pradesh (10.4%), Uttar Pradesh (8.0%) and Gujarat (7.6%) that have high numbers of wetlands.

In case of area coverage concerning total wetland area (of the country), Gujarat (21.9%) has the highest place, followed by Maharashtra (7.2%), Andhra Pradesh (7.14%), West Bengal (7.07%) and Uttar Pradesh (6.9%). Considering the fraction of geographic area of the state under wetlands, Goa has got highest wetland percentage (24.6%), followed by Dadra Nagar Haveli (17.8%), Himachal Pradesh (17.3%), Jharkhand (12.7%) and Andhra Pradesh (11.3%).

As against that, considering the fraction of the total geographic area of the country, Gujarat is the only state which has got more than 1 (one)% of wetlands, other states in sequence are Andhra Pradesh, Maharashtra (0.35%); West Bengal, Uttar Pradesh (0.34%); Tamil Nadu (0.28%) and, Madhya Pradesh, Assam (0.26%).

The Ramsar Convention, an intergovernmental treaty that India ratified in 1981, aims to provide a framework for national action and international partnership to conserve and use wetlands and their resources sustainably. As per the Convention, signatory countries can declare specific wetlands as ‘Ramsar sites’, if they meet one or more of nine criteria (such as if it regularly supports 20,000 or more waterbirds).

To mark World Wetland Day on February 2, the environment ministry designated two new ‘Ramsar’ wetlands in India. This brings India’s Ramsar site tally to 49. It also increases the area under Ramsar sites to 10,93,636 hectares and is the highest in south Asia, giving these wetlands international recognition and more conservation significance.

Wetlands are areas filled with static or flowing water. These could be natural or man-made, and include marshes, fens and peatlands. They could also be inland and coastal. Lakes and ponds, estuaries, swamps, marshes, floodplains of rivers and even man-made water bodies — such as reservoirs that are created when rivers are dammed — qualify as wetlands according to the Indian Ministry of Environment, Forest and Climate Change.

The many ecosystem functions that wetlands provide to both people and biodiversity make it important to conserve them. These include flood control and livelihood support for numerous communities including fishers. Wetlands also support a wide range of biodiversity, from small mammals such as the endangered fishing cat, to migratory birds and invertebrates. They serve as crucial carbon sinks too in the fight against climate change: wetlands have some of the highest soil carbon densities compared to other natural ecosystems.

Designating a wetland as a Ramsar site marks it as a wetland of both national and international significance. One of the two new Ramsar wetlands in India is the Bakhira Wildlife Sanctuary in Uttar Pradesh, which serves as a wintering ground for a large number of species. It is part of the Central Asian Flyway, a route that covers a large area of Eurasia — between the Arctic and Indian oceans — which large numbers of migratory birds regularly use. The other is the Khijadia Wildlife Sanctuary in Gujarat, a coastal wetland with rich avifaunal diversity, which is home to several endangered and vulnerable species.