We find your conclusion premature that there is no longer a direct correlation between food production in Brazil and deforestation in the Amazon (Nature 466, 554-556; 2010).
An increase in demand by international markets for export commodities such as soya beans and beef will mean more rainforest clearance. There is still potential for a huge increase in productivity, given that large producers of export goods are encouraged by government loans at favourable rates and fiscally exempt debt relief, which in turn attract investment in research and development.
Moreover, Brazil's Congress has proposed large structural changes to the Forest Code that could lead to further deforestation and threaten the preservation of the most important Brazilian biomes.
Brazil's own staple crops - rice, beans and cassava - account for very little deforestation. The small farmers producing these still suffer low credit and heavy debts, fragile land tenure, scant investment in crop research, and inferior storage conditions for their products.
A global farm should be socially fair as well as environmentally friendly. Although Brazilian agricultural policy is on the way to meeting these conditions, we are not yet there.