Valuation of Ecosystem Services of Kala Oya River Basin: Implications for River Basin Management

Abstract

Kala Oya Basin (KGB) is one of the largest river basins in Sri Lanka which covers an area of around 2,870 knr and expands over three provinces and four districts. The river basin covers many different types of ecosystems, valuable biodiversity resources and characterized by conflicting user interests and serious degradation issues. The present study attempts valuation of ecosystem services provided by the river basin and aims at providing recommendations for river basin management. Carbon storage and soil conservation functions, recreation, production services of homegardens, and mangrove services were valued using data collectedfrom various primary and secondary sources and using benefit transfer approach as the main valuation method. The annual value of the ecosystem services of the KGB is Rs million 23,500. The highest economic value was resulted from the carbon values (77%). The estimated value represents 1.16% ofGDP (of 2004) of the country and 7.33% of the agricultural sector GDP which highlights the significance of the potential economic gains of the basin. Development of appropriation mechanisms for the yet unrealized values and identification of conservation and monitoring priorities are the key issues identified by the present study However the study emphasizes the needfor more complex models that integrate economics, hydrology, and equity aspects which could ensure long term sustenance of the service provision of the river basin.