CHENNAI: Wetlands and waterbodies, we are told, are invaluable. But do they have an economic value — perhaps a stronger argument against their exploitation than pleas on the basis of ecological significance?
Yes, says a study conducted by IIT-Madras and Tamil Nadu State Land Use Research Board, along with Indo-German Centre for Sustainability. It has fixed the estimated values of Pallikaranai marsh and Pulicat lake as Rs 10.98 crore and Rs 72.04 crore per year, respectively.
The researchers worked out the estimates from a study conducted by the World Wide Fund for Nature in 2004 to compute the economic values of wetlands in Chennai through a benefit transfer method.
Under this method, economic value for ecosystem services is estimated by transferring available information from studies already completed in another location and context.
The WWF study combined the values of 89 different economic valuation studies of wetlands from across the globe using a statistical synthesis approach, to arrive at global and regional values and also values for different types of wetlands.
The study added that the economic value of Pallikaranai marsh and Pulicat lake were studied also by estimating the communities’ willingness to pay for improvements to the wetland and by computing the cost for regeneration of a wetland. In addition, the market value for goods and services provided by the wetland, too, was estimated. However, while there is no dispute among experts about the value of the marshland and the lake, a section disagreed with the valuation.
IIT Madras civil engineering professor S Mohan said that the value could be much higher if the cost of land was taken into account. “The economic value estimate of Pallikaranai marshland is very less. It could be worth more than Rs 100 crore if you consider the land value and ecosystem,” says Mohan. The economic value should be ascribed by evaluating the land value as well as loss of ecology and restoration of the wetland, he said.
The study had admitted the limitations in using the benefit transfer method in valuing ecosystem services, the biggest being the lack of site-specificity in such an estimate, which compromises accuracy.
However, experts feel that while economic values serve as good tools and indicators to be used in decision-making processes, wetlands should not be managed and conserved based on such values alone.
The social and cultural values associated with ecosystems, which are inherently challenged by their intangible nature, must also be given equal importance in decision-making.