Travails of a waterscape
|SIDDHARTHA KRISHNAN AND PRIYADARSANAN DHARMA RAJAN|
Sprawling over 150,000 hectares, it is the largest tropical wetland in India's southwest coast. Ten rivers that originate in the Western Ghats flow into the wetland. Vembanad supports a diverse water fowl and fish population. In the past, farmers were careful in not upsetting the wetland's ecology. But trouble began in the 1950s when large portions of Vembanad were reclaimed by farmers as part of the Grow More Food campaign launched by the post-independent state to deal with grain shortage.
As pioneer farmers drained water and land-filled the drained portions, they created an agrarian aberration: farms below sea-level. The paddy fields they created were lower than water levels that bordered them and fitted well with the idyllic environs.
The crisis But the economics of wetland cultivation makes it far from lucrative. Production costs have spiralled while cultivation has declined. Migration of farm labour, a historical trend that has intensified in the post liberal era, is a decisive factor in the decline. Fish stock has decreased due to land reclamation and pollution. There is high level of duck mortality.
|Idyllic no more: pollution from houseboats |
is one of Vembanad’s worries
The processes that contribute to the health crisis are also conservation challenges. Water stagnation along with reduction of salinity (due to manipulation of sea water flow for paddy cultivation) has created what scientists term as eutrophication. The process involves nutritive pollution that creates conditions conducive for algae-like plants including weeds. Such growth stifles dissolved oxygen. In Vembanad the widespread presence of water hyacinth (Eichhornia crassipes) is a good indicator of eutrophication. This has lead to loss of aquatic life especially fish. Treating such water is extremely difficult.
Health and Conservation Conservationists have a common phrase: threats posed by humans to ecosystems. If people are to have stakes in conserving coastal wetlands, this phrase has to be altered as