The ecological decay of Vembanad backwater system is on the rise owing to intense pollution and unauthorised construction, a study carried out by the School of Marine Sciences at the Cochin University of Science and Technology has revealed.
The study has established that the ecological decay of the wetland is on the rise due to intense pollution and unauthorised construction from the southern to the northern regions of the backwaters.
Violation and relaxation of the Coastal Regulation Zone (CRZ) norms have been recorded in many regions, it has found.
Strict enforcement of the CRZ norms for the backwaters has to be done, observes the study carried by a team led by Dr. S. Bijoy Nandan, Professor and Head, Department of Marine Biology, Microbiology & Biochemistry. The report has been submitted to the Kerala State Pollution Control Board for follow-up action.
The research finding says reclamation of estuarine areas for agriculture has led to a drastic decline in the water holding capacity of the backwaters, which is recognised as a Ramsar site, from 2.4 km3 to 0.6 km3 during the past 50 years. The pollution load indices (PLI) were very high. The higher concentration of cadmium is the main reason for the increase in PLI. The main sources of cadmium pollution are industrial and municipal waste, it says.
The Vembanad backwaters has been continuously subjected to land reclamation for various purposes such as agriculture expansion, harbour development, and urban development. Untreated waste from houseboats is dumped into the waterbody, the report says.
Dr. Nandan suggests that a model based on the carrying capacity needs to be developed on the impact of tourism and related pressures on the wetland.
Action for protecting the Pathiramanal island should be implemented. Special attention should be paid by the Tourism Department to restrict nature tourism.
It must also ensure that no ecological modifications are made to the islands and should promote mangrove afforestation. Strengthening the water bird habitat assessment and monitoring network through training and participation programmes is to be carried out, he says.
The Vembanad wetland was declared a Ramsar site in August 2002, but no serious action has been taken by either the Union or State government to improve the overall ecology and prudent use of the wetland. The reforms under the Ramsar and Kuttanad package need to be strengthened, the report says.
