Revitalizing Sri Lanka’s village tank ecosystems Sisira Rajapakse, Rajarata University of Sri Lanka
Event details
YESI International Fellows seminar
Join us for our next YESI International Fellows seminar and discover how Sri Lanka’s Village Tank Cascade Systems could offer nature-based solutions for climate resilience, rural livelihoods, and sustainable water management.
Rural areas in the dry zone of Sri Lanka have traditionally managed climate variability and water scarcity through Village Tank Cascade (VTCS), which have become less extensive over the centuries. These systems are designed to capture, store, and distribute rainwater in the dry region. Recognizing the importance of the socio-economic and ecological dimensions, VTCS were designated as Globally Important Agricultural Heritage Systems (GIAHS) by the Food and Agriculture Organization (FAO) of the United Nations in 2017.
VTCS are a nature-based solution, offering a range of ecosystem services. VTCS as multifunctional systems that, if revitalized, could transform the dry zone landscape, allowing both the ecosystem and the communities that rely on them to become resilient in the face of a changing climate and water scarcity. However, over the past few decades, this ancient and ecologically rich system has suffered significant degradation due to various factors. These include land-use changes, population pressure, lack of maintenance, the breakdown of traditional governance structures, institutional and policy failures, as well as insufficient recognition of the full economic value of village tank ecosystems.
Current policy and investment decisions often overlook the diverse services these systems offer, primarily because their ecosystem services are poorly understood in monetary terms that allows their value to be financially captured. For instance, local decision-makers tend to focus only on the market driven benefits, particularly irrigation benefits of individual tanks and may conclude VTCS is not often economically feasible and less incentive to invest in enhancing their broader ecosystem services. These pressures not only threaten the sustainability of the tank ecosystems but also undermine the socio-economic stability of the communities that rely on them.
To encourage thinking across the entire socio-ecological system, it is important to recognize and value the full range of ecosystem service benefits and to explore the potentials of implementing Payments for Ecosystem Services (PES) mechanisms to enhance village tanks ecosystems to changing environmental conditions and enhance rural livelihoods. Valuation of ecosystem services and preferences can provide the economic justification for implementing a PES scheme which can incentivize local participation in conservation, secure sustainable financing various sources for system maintenance, and enhance livelihood of the farming communities. In terms of implementing PES, we focus on individual village tank with varying levels of restoration and ecosystem service provision, to cover the spectrum of tanks that the PES scheme could cover. This targeted approach allows for a clearer assessment of the potential values and preferences towards a PES scheme focused on either rewarding ecosystem service outcomes or by rewarding restoration inputs to form an evidence-based foundation for future scaling.
About the speaker
Sisira Rajapakse (PhD), Senior Lecturer in the Department of Environmental Management at Rajarata University of Sri Lanka. Graduated with First Class Honors in B.A. (Hons) in Environmental Management and subsequently an MSc in Environmental Economics from Sri Lanka. He completed his PhD at the Sustainability Research Institute, School of Earth and Environment, University of Leeds, UK, where he was awarded the Commonwealth Scholarship. His doctoral thesis, was titled ‘Economic Valuation of Water Service Improvements in the North Central Province of Sri Lanka. Additionally, he had the opportunity to study at the Department of Environmental Science at Aarhus University, Denmark, as a visiting research scholar.
At both national and international levels, he has been actively involved in and managed various research projects, collaborating closely with policy-making bodies and international organisations. He specialises in Environmental Economics, with teaching and research focusing primarily on environmental valuation, environmental policy analysis, environmental accounting, sustainable financing, Nature-based Solutions (NbS), environmental impact assessments, and cost-benefit analyses.