The agro-ecocomplexes of traditional villages in the Dry Zone of Sri Lanka included four major components, namely crop cultivation, animal husbandry, fishery, and forestry. While these four components collectively provided practically all the food and other needs of the village inhabitants, the ecological interactions between these components contributed to the sustainability of the village agro-ecocomplex. Thus the livestock were used to provide draught power for farming, and were fed on crop residues and straw, their dung being used to fertilize the soil. Fishery was mainly on irrigated paddy fields and in the irrigation system, while the fish on the paddy fields consumed harmful insects and worms, and provided fertilizer in their excreta. The village forest on the catchment area, and the trees sparsely grown on the cultivated area and in the irrigation system, substantially contributed to maintain the natural productivity, yielding firewood, timber, and various foods. In this manner, the village agro-ecocomplex functioned to satisfy the needs of its human inhabitants without impairing its own sustainability.

This village agro-ecocomplex system is now in the process of disintegration owing to structural, technological, and institutional, changes brought about by modem development. The reason is that these modern development strategies were basically designed to raise the production of the land-area rather than to preserve the productivity of the given agro-ecocomplex. For while farm mechanization displaced the draught animals, the increased population pressure of more and more humans reduced the grazing lands. Both modern development and population pressure had destructive effects on the forest cover, while increased utilization of agrochemicals adversely affected the fish culture on paddy fields. In this way, livestock, fishery, and forestry, all became insignificant or at least insufficient, and were de-linked from crop cultivation. In consequence, the village agro-ecocomplex has become de-stabilized, and dependence on external inputs has increased so greatly that self-sustainability of the village agro-ecocomplex has ceased to exist except in some remote areas.

Conservation must be set in a context in which it is recognized that:

(i) Overall human impact on The Biosphere is the product of the number of people on Earth multiplied by the average impact per person. Both of these factors are continuing to increase although there is already compelling evidence that the present level of impact is exceeding the carrying capacity of the planet.

(ii) The ability of the Earth's natural systems to tolerate different types of impacts varies from place to place. Not surprisingly it is in the world's tropical and arid regions, where rapid population-growth often coincides with ecological systems which are less able than most others elsewhere to tolerate intensive utilization, that many of the world's most intractable ecological problems are found.

(iii) All countries must endeavour to minimize population growth and reduce the environmental impact per person until the overall global impact is reduced to a level at which all peoples can expect to be able to have a comparable but ecologically sustainable level of impact.

(iv) Achieving sustainable levels of impact will require an unprecedented degree of international cooperation. This will involve at its core due recognition that ecologically sustainable development can best be achieved in conjunction with continued economic and social development. It will also require due recognition of how new, ecologically sustainable, technologies will often be the key to ensuring that such continued development is indeed ecologically sustainable.

(v) There is at present insufficient recognition in the industrialized, i.e. ‘developed’, countries that their failure to pay ecologically realistic prices makes it extremely difficult, if not impossible, for commodity producers to follow ecologically sustainable practices. The consequence is land degradation in countries that are dependent on commodity exports, and a diminished or degraded global environment overall.

(vi) There is a strong case for preserving Antarctica from development because of its importance in influencing global weather and climate, and because of its ecological fragility and biological uniqueness. To preserve it as a wilderness will be an important test of international resolve to manage such resources as are still accessible in the rest of the world in an ecologically sustainable manner.