THIRUVANANTHAPURAM: All may seem hunky-dory and celestially beautiful at Vellayani, with its misty mornings and eco-tourism initiatives evoking considerable charm. But this picture-perfect setting exists only along its banks. Wade into the waters, and the choking of the lake becomes evident in more ways than one.
With over 50 per cent of the lake infested with invasive species, both foreign and native, the ecological impact has led to changes in groundwater quality and fish populations, as well as a decline in the visitation of migratory birds.
One of the main villains among these weeds is the water hyacinth, which has been making headlines for its invasion not just of Vellayani but most of Kerala’s water sources. Scientists like Ajith Haridas, former head of CSIR-NIIST, believe this is a direct reflection of the lack of proper sewerage treatment in Kerala.
“Agriculture and the use of fertilisers are less in Kerala, it being a state with sparse agri initiatives. So, the sewerage is the culprit here, which grants nitrogen and phosphorus into the waters. The treatment facilities here are at least 50 years old. So, the waste is let into the waters, adding to its nitrogen and phosphorus content which results in blockage of light and growth of weeds like water hyacinth. It literally chokes the health of the lake ecosystem and its adjoining ecology,” says Ajith.
This issue has been rampant in Kerala, and from time to time, efforts have been made to bank upon the weeds to create value-added products. The recent initiatives of some universities to address this problem have brought it into the limelight again. Similarly, the efforts of institutions like CSIR-NIIST to collaborate with local administrative bodies such as the Nemom block panchayat are being seen as steps towards highlighting the issue boldly, if not solving it completely.
Nemom panchayat’s latest initiative is to tie up with CSIR-NIIST to develop value-added products, a move seen as an attempt to contain the hyacinth infestation to some extent. “The idea was mooted at the recently held innovation cluster meeting in which the issue of how hyacinth infestation was affecting the lake and its ecology was raised,” says Nemom block panchayat officer P R Ajayghosh,
“CSIR-NIIST then offered to collaborate with us on a strategic plan to make value-added products from the weed, which would also be a source of income for local people of the Kalliyur panchayat. The project is approved, and the MoU is likely to be signed in September.”
The technology to be used for the project would be closed retting or treating the weeds by containing them in a closed space — a process invented by Ajith. “Water hyacinth or Eichhornia crassipes infests lakes when the water is contaminated. In case the lake is relatively free from lead, mercury, arsenic, etc., as perceived by a few scientists, the results can be very good, even surprising,” says R S Praveen Raj, senior principal scientist at CSIR-NIIST, Thiruvananthapuram.
“If so, the narrow, pathogen-free fibres, after detoxification and drying, can be used as feed for fish and livestock, medicinal applications, including biodegradable wound dressings for diabetic patients. However, extensive research would be needed for this.”