COLONISED COASTS AQUACULTURE AND EMERGY FLOWS IN THE WORLD SYSTEM: CASES FROM SRI LANKA AND THE PHILIPPINES
This thesis conceives aquaculture as a transfer of resources within and between different parts of the world system. It is argued that due to inappropriate human-nature interactions, resources tend to flow from the South to the North, as a process of coastal colonisation. To study this resource transfer, coastal aquaculture is approached from a transdisciplinary perspective, integrating natural, social, economic and spatial aspects. By combining world system theory and general systems theory, a systems view is adopted to relate aquaculture to forces of global capitalism, and analyse interactions between social and ecological processes at local and global levels. Emergy (energy memory) synthesis and participatory research methodologies were applied to two cases of aquaculture in Sri Lanka and the Philippines; monoculture of the black tiger prawn (Penaeus monodon) and milkfish (Chanos chanos), and polyculture of the two species together with mudcrab (Scylla serrata). The study reveals that semi-intensive shrimp monoculture in Sri Lanka generates few benefits for poor local people, and depends much on external inputs such as fry, feed and fuels, which implies negative environmental effects at local as well as global levels. Extensive polyculture in the Philippines involves more local people, and implies lower dependence on external inputs. Still, since benefits accrue mostly to elites, and mangroves are negatively affected, neither case is viable for sustainable poverty alleviation. Nevertheless, the study offers several insights into how sustainability assessment may be more transdisciplinary, and points to several factors affecting sustainability and fairness in aquaculture; the most important being mangrove conversion, local people involvement, and dependence on external inputs. Given that mangrove conversion is counteracted, extensive polyculture practices may also prove more viable in times of decreasing resources availability, and if policies are developed that favour resource efficient polyculture, and local small-scale and re-source poor farmers, instead of the global North.