Wetlands : Nature's kidneys

N Munal Meitei *

The scenic spot on Loukoipat Lake in March 2009 :: Pix - WT

Wetlands play a very important role in maintaining the ecological balance. They harbor and prevent plants and animals from extinction. They are the sponges for floods, purify, filter and recycle organic wastes and regulate and replenish the water. The theme for 2023 is Wetlands Restoration and this theme is selected to demonstrate the vital role of wetlands for human survival and other living beings.

While the forests are called the lungs of earth, the wetlands are the kidneys for nature. They are critically important ecosystems and are the cradle for biodiversity. Wetlands are called "nature's supermarket" for food, raw materials, genetic resources for medicines and hydro power.

Wetlands are the primary sources of fresh water, natural buffers against floods and droughts. Wetlands minimize the impacts of climate change mitigation and adaptation storing 30% of land based carbon. Wetlands build community resilience to disasters and absorb pollutants.

Wetlands are the ecotones, providing a transition between land and water bodies and provide the wildlife habitats for the aquatic animals and the migratory birds. Wetlands are highly productive and bio-diverse Eco-systems that support a home to about one third of all the threatened and endangered species.

Wetlandsare ideal for development of organisms that form the base of the food web and feed many species of fish, amphibians, shellfish and insects. More than one billion people depend on wetlands for living and 40% of the world's species live and breed in wetlands. They play an important role in transport, tourism and the cultural and spiritual well-being.

Wetlands are the source of 95% of the world's drinking water. Wetlands purify and filter harmful wastes from pesticides, industry and mining, including heavy metals and toxins. Rice and fish from wetlands, are the staple food for nearly three billion people and accounts for 20% of the world's nutritional intake. Wetland stimulates plant recruitment from diverse seed bank and increase productivity by mobilizing nutrients.

Wetlands act as nature's shock absorbers. Peatlands alone store more than twice as much carbon as all the forests in the world. The role of forests to our wetland is vital and richness of our wetlands depend upon the luxurious of our forests.

Wetlands near urban centres are under pressure for residential, industrial and commercial facilities. Vast stretches of wetlands have been converted to paddy fields and fish farms. Construction of reservoirs, canals and dams have altered the wetland hydrology.

The removal of materials from lowlands and riverbeds lowered the surrounding water table and dries up the adjacent wetlands. Dying up or blocking of streams are the main causes for death of the wetlands. Wetlands are threatened by water plants like hyacinth and salvinia which clog waterways and compete with native vegetation.

But now wetlands are the most threatened ecosystem. Nearly 90% of the world's wetlands have been degraded since the 1700s and wetlands are disappearing 3 times faster than forests due to human activities and global warming. A small change in temperature and rainfall would be impacting on 40% of the world's flora and fauna that live or breed in wetlands.

Unfortunately, wetlands are often viewed as wasteland. In reality, wetlands play a critical role in maintaining many natural cycles. Wetlands are aquatic islands in terrestrial sea harbouring a limited array of species populations that arrange themselves in a number of configurations (Pomeroy, 1991).

Wetlands are important in supporting species diversity of the biosphere being the habitat of 20% of all living organisms representing all taxonomic groups on the earth. (Mitsch and Gosselink, 1986). Wetlands are home to more than millions known freshwater species but the richness of wildlife and our biodiversity - has declined by 76% in the last forty years, according to WWF's Living Planet Index.

India has nearly 4.6% of its land as wetlands, covering an area of 15.26 million hectares and has 75 Ramsar Sites. Thus 10.2% of the earth's total wetlands are found in India. Our wetlands support around 5100 species of flora and fauna. They represent 23% reptiles, 13% amphibians, 23% fishes, 65% birds and 26% mammalian species.

Wetlands in India support 20% of all the known range biodiversity in the country (Deepa and Ramachandra, 1999). But we have lost 30% of our wetlands due to urbanization, land use pattern and pollution.

Manipur, surrounded by many hills has numerous wetlands but majority of them are in dying state. Almost all the migratory birds in the State are coming to these wetlands. The State has 155 lakes and 2 ox-bow lakes occupying 2.37% of the geographical areas. About 134 waterlogged marshy and swampy wetlands are also found in the State. But more than 64% of our wetlands have disappeared during the last eight decades.

The number of wetland flora so far identified are 86 species in which 13 are clear water and 73 are semi aquatic. The State has 110 species of amphibians and reptile among 580 species so far found in the country.

We also have counted 120 species of fishes while the country owned 1700 fish species. Such a faunal richness of our wetlands represent 10.80% of the whole country though we have only 0.7% of the geographical area.

Loktak Lake with an area of 287 sq. km, is the largest fresh water lake in North East. Around 12 towns and 52 settlements with over 14% of State's population depend directly or indirectly on Loktak Lake. Other important wetlands are Kharungphat, Khoidumpat, Pumlenpat, Loukoipat, Sanapat, Yaralpat, Poiroupat, Ikopat, Waithoupat and Loushipat.

These lakes remain threatened due to artificial eutrophication and large scale encroachment. Soil erosion due to indiscriminate deforestation in the catchments followed by the change in the land use pattern inside the wetlands are the roots for the speedy dying of our wetlands. Excessive deposition of plastics and other harmful wastes are also another big challenges.

Enabling people for a decent living and at the same time ensuring the conservation and safety for wetlands are the primary objectives of this day. This is the ideal time to increase the people's understanding of these critically important ecosystems. Therefore, let's join hand to save our wetlands for a better tomorrow.