Local perceptions of environmental change in a tropical coastal wetland: The case of Koggala Lagoon, Galle, Sri Lanka.

Abstract

Tropical coastal wetlands are under ecological stress, most notably due to accelerated development activities associated with these areas. Consequently, natural resource depletion and environmental problems in the coastal sector are increasingly serious issues, particularly in South and South East Asia, and have significant implications for their traditional resource-user groups. This thesis is primarily based on a detailed investigation of the inter-relationships between environmental change and local perception of change at Koggala, Galle, southern Sri Lanka, where six sample Divisions bordering Koggala Lagoon were selected for in-depth study. Multi-disciplinary techniques from both the natural and the social sciences were employed, focusing on the environmental changes involved and on the perceptions of these changes by local fishing and farming communities. Particular attention was paid to changes in agriculture, to the reconfiguration of a coastal sand bar, and to the development of a Free Trade Zone. Participatory techniques involved the experimental use of group discussions. Visits were made to Malaysia and Thailand for comparative study purposes. Results show that the fringing mangrove complex is currently threatened by a number of factors and that sand mining close to the lagoon outlet has severely disrupted water levels in the lagoon and ultimately rice-farming systems. The fishing community further perceives significant declines in their fish catch, attributing this to the loss of fishery nursery sites and to the seepage of agro-chemicals, some belonging to highly toxic groups, into the lagoon. It is clear that local communities display a high degree of awareness of environmental change, as well as of the causes of this change. Such understanding can be used to develop local-level adaptive planning for wetland management. The use of discussion groups is seen as a novel approach to such wetland management programmes in the tropics.