ABSTRACT
In Western agricultural economics, it is difficult to find any loss of agricultural biodiversity. International policies on biodiversity will be guided by the theory of an 'optimal portfolio' - how to conserve the 'appropriate' amount of biodiversity, neither too little nor too much. The increase in production for the market spoils the very conditions necessary for this production, namely, agricultural biodiversity. In opposition, a growing popular ecological movement seeks to defend agricultural biodiversity, not through the market, but through political and social movements favouring ecological agriculture. Modem agriculture, based on varieties that have been improved by nontraditional techniques, greater production per acre and high fossil fuel energy input, has led to the reduction of biological diversity in agricultural systems. The development of hybrid corn, varieties of wheat and rice, set off the current process of genetic erosion within an agricultural system based on mechanization and infield monoculture.
