Wetlands: Functions, Threats & More

Wetlands are often referred to as the kidneys of the landscape for their ecological importance. These ecosystems play a crucial role in maintaining ecological balance, supporting biodiversity, and providing essential ecosystem services. This article aims to study in detail the Wetlands, their types, functions, importance, threats faced, and conservation efforts taken, including the Ramsar Convention and Montreux Record, among others.

What is a Wetland?

• It refers to an area where water is the primary factor controlling the environment and the associated plant and animal life.
• They occur in the areas where the water table is at or near the surface of the land or where the land is submerged under water.
• Once treated as seral stages in succession or transitional habitats from open water to land, they are now recognised as distinct ecosystems with their unique and specific ecological characteristics, functions and values.

Types of Wetlands

• Broadly, these ecosystems are categorised into two types: Inland, and Coastal
• Each category is further sub-categorized into the following types.

Functions of Wetlands

These ecosystems provide a variety of functions that are crucial for humans and the environment as can be seen as follows:

• Water Purification: They contribute to enhancing water quality by filtering out inorganic nutrients, processing organic waste, and reducing suspended nutrients.
• Role in the Hydrologic Cycle: By receiving, storing and releasing water in various ways, they play an important role in the hydrologic cycle.
• Processing of Carbon and Other Nutrients: They play a crucial role in the biogeochemical cycle, which includes the physical, chemical, and biological transformation of various nutrients within living organisms, soils, water, and air.
  • They create the necessary conditions for the removal of phosphorus and nitrogen from surface water.
• Stabilization of Shorelines: As they are generally located at the margins of rivers, lakes, bays, and oceans, they protect the stream banks and shorelines against erosion.
  • The plants and trees in these ecosystems hold the soil with their roots, absorb the wave energy and break up the flow of streams or currents.
• Atmospheric Maintenance: They store carbon within their living and preserved plant biomass instead of releasing it into the atmosphere as carbon dioxide and thus help in moderating the global climate.
• Deal with Environmental Problems: They help mitigate environmental issues like algal blooms, dead zones, and fish kills, which are often associated with nutrient overloading.
• Maintaining Water Supply: They help maintain streamflow during dry periods and replenish groundwater, thus maintaining the water supply.
• Habitat for Various Organisms: They serve as habitats for fish, wildlife, and plants, with many species relying on them for survival.
• Prevention from Flood: Due to their low topographic position, they store and gradually release surface water, rain, groundwater, snowmelt, and floodwaters.
  • Wetland vegetation also obstructs the movement of floodwater and distributes it more slowly and gradually over floodplains.
  • They also prevent waterlogging of the nearby agricultural lands.
• Economic Benefits: They support many plant species that possess economic and medicinal values. For example, wild rice, blueberries, etc.
• Source of Livelihood: Local people rely on them for various commercially valuable resources, helping to meet their daily needs.
• Recreation, Education, Research, and Aesthetic Activities: They serve as sites for research and recreational activities.
  • Many people visit these water-logged areas for birdwatching or wildlife photography.

Importance of Wetlands

Some of the major importance of these ecosystems can be seen as follows:

• They are some of the most productive environments globally, serving as centers of biological diversity that supply the water and resources essential for the survival of numerous plant and animal species.
• They are essential for the many benefits or ‘ecosystem services’ they offer humanity, including freshwater supply, food, building materials, biodiversity, flood control, groundwater recharge, and climate change mitigation.
• They absorb pollutants, improve water quality, protect our shores from wave action, reduce the impacts of floods, and mitigate the effects of natural disasters like cyclones and tidal waves.
• They are the vital link between land and water and provide habitat for animals and plants.
• They harbor a rich diversity of life, supporting unique plant and animal species not found elsewhere.
• They support hundreds of thousands of people, both directly and indirectly, by providing essential goods and services.
• During heavy rainfall, their ability to absorb excess floodwater prevents potential flooding, helps maintain a steady flow downstream, preserves water quality and boosts biological productivity for both aquatic life and local human communities.
  • Inundated lands are highly effective at storing rainwater and serve as a key source for replenishing groundwater aquifers.
• They also provide shelter and food for mammals.
  • Many waterfowl like egrets, herons and cranes nest in these areas.
• They function as natural filters, effectively removing a variety of pollutants from water, such as harmful viruses from sewage and heavy metals from industrial sources.
• They help retain nutrients by capturing eutrophic elements like nitrogen and phosphorus in the subsoil, thereby reducing the risk of eutrophication.

Threats to Wetlands

The survey of Wildlife Institute of India reveals that around 70-80% of individual freshwater lakes and marshes in the Gangetic floodplains have been lost in the last five decades. They are disappearing at a rate of 2-3% every year.

Some of the major threats to these ecosystems are as follows:

• Urbanisation: Wetlands near urban areas are facing increasing developmental pressure for residential, commercial and industrial facilities. E.g. Bellandur Lake, Bengaluru.
• Anthropogenic Activities: Unplanned urban and agricultural development, along with industrial activities, road construction, impoundments, resource extraction, and dredge disposal, have led to the draining and transformation of such lands, resulting in significant long-term economic and ecological losses. E.g. Great Lakes of USA.
• Agricultural Activities: After the Green Revolution of the 1970s, large areas of such lands have been converted into paddy fields. Also, construction of a large number of canals, damns, and reservoirs to provide for irrigation significantly altered their hydrology. E.g. Shahpura Lake of Bhopal.
• Hydrologic Activities: The construction of canals and the diversion of streams and rivers to deliver water to arid regions for irrigation have disrupted drainage patterns and significantly degraded them.

Ramsar Convention on Wetlands

• The Ramsar Convention, officially known as the Convention on Wetlands of International Importance, is an intergovernmental treaty that establishes a framework for international cooperation and national efforts aimed at conserving and sustainably using wetlands and their resources.
• It was signed in Ramsar (Iran) on 2 February 1971 and entered into force on 21 December 1975.
• Initially focused on the conservation and sustainable use of wetlands mainly to provide habitat for water birds, the Convention has since expanded its scope to cover all aspects of wetland conservation.
• Under the Convention’s ‘three pillars,’ the Contracting Parties are committed to:
  • Work towards the wise use of all their wetlands;
  • Designate suitable wetlands for the list of Wetlands of international importance (the “Ramsar List”) and ensure their effective management;
  • Cooperate internationally on transboundary wetlands, shared wetland systems and shared species.
• Currently, there are 169 parties to the Ramsar Convention.
• Currently, India has 75 Ramsar sites.

Montreux Record

• The Montreux Record, under the Ramsar Convention, is a list of wetland sites from the List of Wetlands of International Importance where changes in ecological character have occurred, are occurring, or are anticipated due to technological developments, pollution, or other human activities.
• It is maintained as part of the Ramsar List.
• Montreux Record is employed to identify priority sites for positive international and national conservation attention.
• Sites can be added to or removed from the Montreux Record only with the consent of the Contracting Parties in which they are located.

Conclusion

Wetlands are invaluable ecosystems that provide critical services to humanity and support a vast array of biodiversity. Protecting and sustainably managing these ecosystems is essential for ecological balance, climate regulation, disaster mitigation, and human well-being. By addressing threats and implementing comprehensive conservation strategies, we can ensure the preservation and resilience of these vital ecosystems for future generations.

Frequently Asked Questions (FAQs)