The suo motu public interest litigation by the Meghalaya High Court very recently, to monitor the conservation of wetlands in the State brings the focus back on this important ecosystem. Since 1971, February 2 is observed every year as ‘World Wetland Day’ to mark the adoption of the Ramsar Convention, an international treaty for the conservation of wetlands, which was signed in the Iranian city of Ramsar. The theme this year was ‘Protecting Wetlands for Our Common Future”. It is a theme that has appropriately positioned wetlands in the sustainable development perspective, as espoused in the Brundtland report, ‘Our Common Future’, and published by the UN World Commission on Environment and Development in 1987.

Many pressures

Wetlands, one of the most biologically productive ecosystems, provide multiple benefits. Globally, wetlands cover an area of 12.1 million km², or around 6% of the earth surface, providing 40.6% of global ecosystem services. However, they are under severe stress, both qualitatively and quantitatively, due to various development activities including population growth, urbanisation, industrialisation, and increasing demand for land to cater to various human needs and climate change.

Since 1900, as much as 50% of the area under wetlands has been diverted to accommodate various other uses, as one of the studies indicated. Wetland surface area, both coastal and inland, declined by about 35% between 1970 and 2015. Globally, the rate of loss estimated with the Wetland Extend Trends (WET) index is (-)0.78% a year, which is more than three times higher than the loss rate of natural vegetation as estimated by the Food and Agriculture Organization of the United Nations. Around 81% of inland wetland species population and 36% of coastal and marine species have declined since 1970. The extinction risk of wetland species, both plants and animals, is increasing, globally.

The conservation and the management of wetlands have emerged as a major challenge as they are linked to other development issues and can serve in devising nature-based solutions for water management and the mitigation of climate change impacts, besides providing blue-green infrastructures in urban areas. Recognising the importance of wetlands in the larger development context, the Ramsar Convention COP14 that was held in Wuhan, China and Geneva, Switzerland from November 5-13, 2022, laid stress on preparation of the fifth Ramsar Strategic Plan and recognised that the conservation and management of wetlands cannot be a stand-alone initiative. It needs to be contextualised and appropriately linked to other international environment development initiatives.

Accordingly, the COP14 argued that implementation of the Ramsar Strategic Plan would be an important contribution towards the achievement of the Sustainable Development Goals, meeting the Global Biodiversity targets, the United Nations Framework Convention of Climate Change. It would also align with the UN Decade on Ecosystem Restoration, and any relevant work of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), the Intergovernmental Panel on Climate Change (IPCC) and other global programmes relating to wetlands. The global changes resulting from the COVID-19 pandemic and greater knowledge about the impacts of biodiversity loss and climate change since COP13, or the 13th Meeting of the Conference of the Parties to the Ramsar Convention on Wetlands (2018), reinforce the urgency to arrest the loss of wetlands.

The situation in India

India is a signatory to the Ramsar Convention. As of 2023, the Ministry of Environment, Forest and Climate Change has designated 75 Ramsar sites (wetlands of international importance) in the country. These are distributed from the coasts to Himalayan territory, and are diverse in nature. Even some of the river stretches such as that of the Upper Ganga river are designated as Ramsar sites.

However, identification of Ramsar site does not necessarily contribute to its conservation. Moreover, the area under Ramsar sites together cover 1.33 million hectares or around 8% of 15.98 million ha wetlands, presently known and mapped as reported in the National Wetland Decadal Change Atlas, 2017-18 prepared by Space Applications Centre (SAC), Government of India. Based on the location, wetlands are classified as inland and man-made. By 2017-18, India had 66.6% of wetlands as natural wetland (43.9% as inland wetland and 22.7% as coastal wetland).

The area under wetlands is not a static figure. The general trends indicate a reduction in natural wetlands and an increase in man-made wetlands across the country. The SAC study showed that natural wetlands along the coast are declining even in a short span of 2006-07 to 2017-18. According to an estimate by the Wetlands International South-Asia (WISA), nearly 30% of the natural wetlands in India have been lost in the last four decades due to urbanisation, infrastructure building, agricultural expansion and pollution. The loss is more in urban areas, especially around major urban centres. It is reported that from 1970 to 2014, Mumbai lost 71% of its wetlands.

Another study has shown that wetlands in east Kolkata have shrunk by 36% in 30 years from 1991 to 2021. A recent WWF study has indicated that Chennai has lost 85% of its wetlands. There have been several studies indicating the loss of ecosystem services due to the degradation of wetlands around the world. One such study, of Cali city in Colombia, has brought out that the estimated loss of total ecosystem services due to loss of urban wetlands is $76,827 a hectare in a year. In the peri-urban area the loss is estimated at $30,354 a ha a year.

The bigger dimension

At present, most wetland management initiatives in India address the ecological and environmental aspects of the wetland ecosystem. The studies are also limited to some of the major wetlands. At the global level, apart from wetland biodiversity, there is stress on wetland distribution and a characterisation of wetland and human impacts to evaluate and prioritise wetlands for conservation.

Given the varied ecosystem services and values that they offer to society, wetlands form an integral part of ecological, economic and social security. It is important to recognise this larger dimension and investigate the physical, social and economic factors, including alterations, in land use within the catchment area, the drivers which have led to modifications in wetland surroundings, and the ex-situ pressure contributing to wetland degradation and the governance structure.

Wetlands act as a source as well as sink of carbon. Therefore, their role in climate change mitigation has to be carefully evaluated and monitored, something which is hardly attempted now. More effective and comprehensive management strategies are required in response to escalating stress from various climatic and anthropogenic factors. The present approach is insufficient to address all these issues. Wetland management warrants an innovative ecosystem-based approach and it should be mainstreamed within the development plan, as advocated during the Ramsar COP14.

Srikumar Chattopadhyay is Scientist (retired), Centre for Earth Science Studies, Thiruvananthapuram and Consultant, Kerala Development and Innovation Strategic Council, Thiruvananthapuram