New estimates of the impacts of germplasm improvement in the major staple crops between 1965 and 2004 on global land-cover change are presented, based on simulations carried out using a global economic model (Global Trade Analysis Project Agro-Ecological Zone), a multicommodity, multiregional computable general equilibrium model linked to a global spatially explicit database on land use. We estimate the impact of removing the gains in cereal productivity attributed to the widespread adoption of improved varieties in developing countries. Here, several different effects—higher yields, lower prices, higher land rents, and trade effects—have been incorporated in a single model of the impact of Green Revolution research (and subsequent advances in yields from crop germplasm improvement) on land-cover change. Our results generally support the Borlaug hypothesis that increases in cereal yields as a result of widespread adoption of improved crop germplasm have saved natural ecosystems from being converted to agriculture. However, this relationship is complex, and the net effect is of a much smaller magnitude than Borlaug proposed. We estimate that the total crop area in 2004 would have been between 17.9 and 26.7 million hectares larger in a world that had not benefited from crop germplasm improvement since 1965. Of these hectares, 12.0–17.7 million would have been in developing countries, displacing pastures and resulting in an estimated 2 million hectares of additional deforestation. However, the negative impacts of higher food prices on poverty and hunger under this scenario would likely have dwarfed the welfare effects of agricultural expansion.

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This article investigates the relationship between international trade patterns and the global distribution of coarse grain production responses to market developments in the United States. Our null hypothesis is that world markets are fully integrated, rendering the geographic persistence of bilateral trade flows irrelevant in the global production response to a change in U.S. prices. The alternative hypothesis allows price transmission to vary along with the intensity of competition among countries in specific markets. Using data from 1975 to 2002, we reject the null hypothesis. Our work has direct implications for the analysis of the global land use impacts of biofuel mandates.

Increasing agricultural yields seem an obvious way to satisfy increasing demands for food and fuel while minimizing expansion of agriculture into forest areas; however, an influential literature worries that promoting agricultural innovation could enhance agriculture's profitability thereby encouraging deforestation. Clarifying the effects of agricultural technological progress on deforestation is therefore crucial for designing effective policy responses to the challenges faced by global agriculture. In this article we review the empirical evidence on these effects and synthesize estimates of future global cropland expansion. Our main insights are that: (i) the empirical evidence on a positive link between regional technological progress and deforestation is much weaker than what seems generally accepted; (ii) at a global level, most analysts expect broad based technological progress to be land saving; however, composition effects are important as low‐yield, land‐abundant regions are likely to experience further land expansion. Toward the future, empirical work understanding how localized technological progress in agriculture transmits through international trade and commodity markets will help to bridge the gap between the findings of local, econometric, studies on the one hand and global, model based, studies on the other.