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What is a wetland?

A wetland is a land area that is saturated or flooded with water either permanently or seasonally. Inland wetlands include marshes, peatlands, lakes, rivers, floodplains, and swamps. Coastal wetlands include saltwater marshes, estuaries, mangroves, lagoons and even coral reefs. Fish ponds, rice paddies and salt pans are human-made wetlands.

What is World Wetlands Day?

World Wetlands Day is a global awareness campaign celebrated every year on 2 February to highlight the value of wetlands. This day also marks the anniversary of the Convention on Wetlands, an intergovernmental treaty adopted in 1971 and which now has a global membership of 172 countries, officially known as Contracting Parties.

Who is behind World Wetlands Day?

The Secretariat of the Convention on Wetlands is the main organizer. Contracting Parties of the Convention on Wetlands have been celebrating World Wetlands Day since 1997.

United Nations International Day

In 2021, World Wetlands Day was designated a United Nations International Day by the UN General Assembly, which invited all 193 UN member states, observer organizations and stakeholders to observe it.

Why do wetlands need an awareness day?

Wetlands deliver essential services for humans, from filtering our water supply and providing water, to protecting us from storms and floods, sustaining biodiversity and storing carbon. More than 35% of wetlands have been degraded or lost since 1970, and this loss is accelerating. World Wetlands Day aims to increase public awareness of how much wetlands do for humanity and the planet, to promote actions that will lead to their conservation, wise use, and restoration.

Wetland Types

The wetlands show several characteristic features that are determined by the combination of salinity of the water, soil types and flora and fauna in that habitat. The wetlands are categorized into different types.

• Marine (coastal wetlands including coastal lagoons, rocky shores, and coral reefs)
• Estuarine (including deltas, tidal marshes, and mangrove swamps)
• Lacustrine (wetlands associated with lakes)
• Riverine (wetlands along rivers and streams) and
• Palustrine (meaning “marshy” - marshes, swamps and bogs)


In addition, there are human-made wetlands such as fish and shrimp ponds, farm ponds, irrigated agricultural lands, salt pans, reservoirs, gravel pits, sewage farms and canals. The Ramsar Convention has adopted a Ramsar Classification of Wetland Types which include 42 types, grouped into three categories: Marine and Coastal Wetlands, Inland Wetlands, and Human-made Wetlands.

Wetland values

Wetlands provide tremendous economic benefits, for example water supply (quantity and quality); fisheries (over two thirds of the world’s fish harvest is linked to the health of coastal and inland wetland areas);agriculture, through the maintenance of water tables and nutrient retention in floodplains, energy resources, such as peat and plant matter, wildlife resources, transport, recreation and tourism opportunities.
In addition, wetlands have special attributes as part of the cultural heritage of humanity. They are related to religious and cosmological beliefs, constitute a source of aesthetic inspiration, provide wildlife sanctuaries, and form the basis of important local traditions.

These functions, values and attributes can only be maintained if the ecological processes of wetlands are allowed to continue functioning. Unfortunately and in spite of important progress made in recent decades, wetlands continue to be among the world’s most threatened ecosystems, owing mainly to the ongoing drainage, conversion, pollution, and over-exploitation of their resources.

Ecosystem services provided by wetlands

Depending partly on wetland’s geographic and topographic location, the functions it performs can support multiple ecosystem services, values,and benefits. Wetlands provide ecosystem services like

  • Water storage (flood control)
  • Groundwater replenishment
  • Shoreline stabilization and storm protection (erosion control)
  • Water purification
  • Reservoirs of biodiversity
  • Pollination
  • Wetland products
  • Cultural values
  • Recreation and tourism
  • Climate change mitigation
  • Climate change adaptation
  • Carbon sequestration
  • Coastal resilience and livelihood

Ecosystem services provided by wetlands

Need for conserving Wetlands

The economic worth of the ecosystem services provided to society by intact, naturally functioning wetlands is frequently much greater than the perceived benefits of converting them to 'more valuable' intensive land use. To replace these wetland ecosystem services, enormous amounts of money would need to be spent on water purification plants, dams, levees, and other hard infrastructure, and many of the services are impossible to replace.

Threats to wetlands

In India, momentous losses of wetlands have resulted from conversion to industrial, agricultural and various other developments. These have caused hydrological perturbations and its various reverberations, pollution and several other effects. The threats can also be distinguished under biotic and abiotic components.

Biotic Threats

• Uncontrolled Siltation And Weed Infestation.
• Uncontrolled discharge of Waste Water, Industrial Effluents, Surface Run-Off Etc. Resulting In proliferation of aquatic weeds and eutrophication, which adversely affect the Flora And Fauna
• Tree felling for fuel wood and wood products causing soil loss affecting rainfall pattern.
• Loss of various aquatic species due to water level fluctuation.
• Habitat destruction leading to loss of fish and decrease in number of Migratory birds.

Abiotic Threats

• Encroachment resulting in shrinkage of area.
• Anthropogenic pressures resulting in habitat destruction and loss of biodiversity.
• Uncontrolled dredging resulting in changes.
• Hydrological intervention resulting in Loss of aquifers.

Wetlands and Climate Change

Wetlands play a key role in buffering the effects of climate change, thereby supporting climate adaptation and resiliency (Millennium Ecosystem Assessment 2005). Indeed, vegetated and healthy wetlands are among the most effective sinks for carbon on the planet. However, this potential is under appreciated in current policy discussions. The carbon sequestration capacity of wetlands is highly variable among different ecosystems, as is their hydrology and productivity. However, among these, seagrass beds (Blue carbon) are known to be very important carbon sinks.

Wetlands are among the ecosystems that are most strongly impacted by even small changes in climate and resulting changes in hydrological regimes, in particular through sea level rise and decreased surface and ground water levels.

wetlands Mitigation and Adaptation to climate change

Healthy wetlands support Mitigation and Adaptation to climate change

Wetlands sequester some of the largest stores of carbon on the planet, but when disturbed or warmed, they release the three major heat-trapping greenhouse gases carbon dioxide, methane, and nitrous oxide. Protecting wetlands from human disturbance helps to limit the increase in greenhouse gases in the atmosphere. Wetland networks also are key corridors and stepping stones allowing species to move to cooler areas and thus adapt to rising temperatures.

wetlands Mitigation and Adaptation to climate change