Livelihoods in the Dry Zone of Sri Lanka have traditionally revolved around paddy cultivation under village tanks. In recent times water-use strategies have responded to a range of demographic and environmental pressures. This has implications for the sustainable management of natural resources, especially living aquatic organisms. The impacts of such change need to be understood at the level of the watershed rather than for individual communities and tanks, the current focus of most dry-land development in Sri Lanka.
Watersheds of Northwest Province are highly complex. Understanding requires a holistic approach, which considers hydrological, biological, social and economic factors. In addition to the well-recognised constraint of seasonal water availability, a range of resource flows which move in both upstream and downstream directions, are critical in determining levels of aquatic productivity. Many of these flows depend on seasonal spill events that link successive tanks within cascading systems. This includes migration routes, which permit the natural recruitment of fish stocks. Rehabilitation initiatives that increase the storage/irrigation capacity of tanks often have negative impacts on these resources flows, yet rarely do planners consider such trade-offs.
The fundamental concept of the 'Purana Complex (PC)' as the smallest logical subcomponent of the watershed for intervention is introduced. Within PC boundaries, discrete community groups, bound by longstanding ties of kinship and caste, control access to private and commonly held natural resources. PCs in uppermost reaches of watersheds are distinguishable by the highly seasonal nature of their tanks, poor physical infrastructure and their lower wealth/caste status relative to lower watershed communities. Such areas are also often buffer zones between as yet uninhabited hinterlands and settled areas where cultivation potentials are further restricted by wild animal incursions. Consequently these groups exhibit greatest dependence on exploitation of the natural resource (NR) base, including fisheries for subsistence purposes. This often includes exploitation of less seasonal tanks in lower PCs, where fisheries are of less significance to local livelihoods. Such low-level 'poaching' is generally well tolerated, but potential for conflict exists where development interventions obstruct hitherto free access to these resources. Existing conflicts in NR management and resolution mechanisms are considered at a range of micro (within watershed) and macro (with outside institutions) levels.
Poor understanding of such functional boundaries has undermined the sustainability of many dry-land development initiatives. We argue that a situation methodology based on these insights can help to target the most relevant groups with a view to improving the equitable distribution of benefits and subsequently the all-round regeneration of the NR base within watersheds.
Towards improved management of living aquatic resources in watersheds of the Dry Zone, Sri Lanka (Draft), University of Stirling, UK, 30 pp.