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Most of the growth in agricultural output in the last thirty years comes from increases in the efficiency with which both land and non-land inputs are used. Recent work calls for a better understanding of whether this efficiency, known as total factor productivity (TFP), contributes to a more sustainable food system. Key to this understanding is the documented phenomenon that, instead of saving lands, the introduction of technologies that improve agricultural productivity encourage cropland expansion. We extend the results of a recently published econometric model of cross-country cropland change and TFP growth to explore the extent to which improvements in technology were associated with lower greenhouse emissions from land conversion to agriculture as well as with lower land conversion pressures in biodiversity-rich biomes. We focus on the decade of 2001-2010, a period in which our sample of 70 countries ( 75% of global croplands) experienced net land contraction. Except in sub-Saharan Africa and South and East Asia, regional TFP growth was associated with regional land expansion, thus confirming the existence of Jevons paradox in most regions of the world. However, such expansion was more than offset by indirect land use effects stemming from increases in productivity somewhere else. These indirect effects are far from trivial. In the absence of TFP growth, our estimates suggest that 125 Mha would have been needed to satisfy demand, half of which are in the four most biodiverse biomes of the world; estimated land use emissions from the ensuing changes in land use range from a lower bound of 17 Gt CO2eq to an upper bound of 84 Gt CO2eq, depending on whether the expansion would have occurred on pasturelands or forest, in contrast to the 1 to 15 Gt CO2eq imputed to observed cropland expansion. Our projections of the land needed to satisfy projected growth in TFP per capita during 2018-2023 indicate that current rates of TFP growth are insufficient to prevent further land expansion, reversing in most cases the in-sample trends in land contraction observed during 2001-2010.

We estimate the effects of agricultural technological progress on cropland expansion at various geographical resolutions, from the country level to the world as a whole, while formally accounting for the international interdependence of national supply responses. Evidence for these effects has thus far been scant, contributing to polarized perceptions about the potential for improving agricultural technologies as a means to slow down deforestation. We find that, in most countries of the world, growth in total factor productivity (TFP) is either uncorrelated or is positively associated with cropland expansion. Yet worldwide TFP growth have been an important source of global land savings. The divergence between the country-level and the global results is explained by the changes in production patterns as countries interact in international markets. Our preferred point estimate of the elasticity of global cropland to global TFP growth is -0.34. Moreover, we estimate that satisfying food demand from 1991 to 2010 without observed TFP growth would have necessitated an additional 173 million hectares, or close to 10% of the area covered by tropical rain forests.

Zero-deforestation supply chain policies that leverage the market power of commodity buyers to change agricultural producer behavior can reduce forest clearing in regions with rapid commodity expansion and weak forest governance. Yet leakage—when deforestation is pushed to other regions—may dilute the global effectiveness of regionally successful policies. Here we show that domestic leakage offsets 43-50% of the avoided deforestation induced by existing and proposed zero-deforestation supply chain policies in Brazil’s soy sector. However, cross-border leakage is insignificant (<3%) because soybean production is displaced to existing U.S. farmland. Eliminating deforestation from the supply chains of all firms exporting Brazilian soy to the EU or China from 2011-2016 could have reduced net global deforestation by 2% and Brazilian deforestation by 9%. Thus, if major tropical commodity importers (e.g., the EU) require traders to eliminate deforestation from their supply chains, it could help bend the curve on global forest loss. This research quantifies the role of zero deforestation policies and potential leakages in Brazilian soybean production, the third major driver of deforestation globally. Here the authors provide the first estimates of net global avoided soy-driven deforestation from zero-deforestation import restrictions and find that such restrictions could help avoid ~40% of deforestation for soy cultivation in Brazil and ~2% of global deforestation.

International trade helps to smooth food price swings caused from seasonal imbalances between domestic supply and demand. Trade also increases the possibility of importing price volatility from abroad. This concern looms large in the face of increased crop yield variability associated with climate change. We assess the extent to which maize yield shocks in exporting countries exacerbate the intra-seasonal variability of maize prices in a cross section of 75 markets in Africa, Asia, and Latin American countries during 2000/01–2017/18. We find that extreme below-trend reductions in maize yields in exporting countries are associated with increased intra-annual maize price variability in the focus countries. In contrast, above-trend maize yields in exporting countries are associated with reduced variability.

Do food imports increase the variability of domestic food prices? The answer to this question depends on whether foreign production is more volatile than domestic production. If imports are likely to destabilize domestic prices, storing crops for future consumption may prove an appealing strategy to cope with the adverse supply effects of a more unstable climate. Unfortunately, public storage has proven to be unsustainable due to the high costs of carrying crop inventories over time and the inability of policy planners to correctly forecast changes in domestic supply. Therefore, understanding the roles of imports and stocks on domestic food price instability is important as domestic shortfalls in food production are likely to become more frequent as the world's climate becomes warmer. Using maize prices observed in 76 maize markets of 27 maize net importers across Africa, Asia and Latin America during 2000-2015, we find that, on average, a 1% increase in the ratio of imports to total consumption is correlated with a 0.29% reduction of the intra-annual coefficient of variation of maize prices; likewise a 1% increase in the amount of maize available in stocks at the beginning of the season is correlated with a 0.22% reduction in the said coefficient. We also find that climate-induced supply shocks toward mid-century may increase maize price variability in the focus countries by around 10%; these increases could be offset with similar increases in the ratio of imports to total consumption or in the stock-to-use ratio at the beginning of the crop marketing year. The fact that both imports and stocks help to stabilize domestic prices suggests that their uses should hinge on a careful cost-benefit analysis, including the risk of facing world production more variable than domestic production and the costs of carrying maize inventories over time.

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.

Global change drivers of land-use/cover change (LUCC) like population dynamics, economic development, and climate change are increasingly important to local sustainability studies, and can only be properly analyzed at fine-scales that capture local biophysical and socio-economic conditions. When sufficiently widespread, local feedback to stresses originating from global drivers can have regional, national, and even global impacts. A multiscale, global-to-local-to-global (GLG) framework is thus needed for comprehensive analyses of LUCC and leakage. The number of GLG-LUCC studies has grown substantially over the past years, but no reviews of this literature and their contributions have been completed so far. In fact, the largest body of literature pertains to global-to-local impacts exclusively, whereas research on local feedback to regional, national, and global spheres remain scarce, and are almost solely undertaken within large modeling institutes. As such, those are rarely readily accessible for modification and extension by outside contributors. This review of the recent GLG-LUCC studies calls for more open-source modeling and availability of data, arguing that the latter is the real constraint to more widespread analyses of GLG-LUCC impacts. Progress in this field will require contributions from hundreds of researchers around the world and from a wide variety of disciplines.

Despite substantial research and policy interest in pixel level cropland allocation data, few sources are available that span a large geographic area. The data used for much of this research are derived from complex modeling techniques that may include model simulation and other data processing. We develop a transparent econometric framework that uses pixel level biophysical measurements and aggregate cropland statistics to develop pixel level cropland allocation predictions. Such pixel level land use data can be used to investigate the impact of human activities on the environment. Validation exercises show that our approach is effective at downscaling cropland allocation to multiple levels of resolution.

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 law-yield, land-abundant regions are likely to experience further land expansion. Toward the future, empirical work understanding haw 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.

We investigate the potential impacts of technical change in oil palm on the forest frontier of Indonesia and Malaysia. Because this is a globally significant problem, we employ a model of the world economy with explicit regional land markets that allows us to capture the land supply response of other countries interacting with Indonesia and Malaysia in international markets. We use a recently available global analysis of yield gaps of major food crops (Fischer, Byerlee, and Edmeades 2012) to analyze two scenarios that represent different pathways of technological change. In our first scenario, oil palm yields in Indonesia and Malaysia experience growth rates that are about three times larger than the average of the last three decades. Such acceleration in yield growth is assumed to come from targeted investments that would close approximately 30% of current yield gaps in the region over a 25-year period. This length of time represents the time needed for new genetic materials to express increases in productivity as they replace older plantations. In this scenario, we assume that productivity in other crops within Indonesia and Malaysia as well as agriculture in the rest of the world remains stagnant. The objective of this scenario is to isolate the effects of regional technological change on the forest frontier of Indonesia and Malaysia. The second scenario is motivated by the notion that improvement of yields globally is an effective way to mitigate climate change (Burney, Davis, and Lobell 2010). Under this scenario we add to scenario 1 crop- and region-specific shocks to close the yield gaps of other oilseeds as well as the main cereals by 35%-a figure that was deemed feasible over the next 25 years, given that average farmer yields rarely exceed 70% of potential yields due to declining marginal returns on inputs and management and risk. Reprinted by permission of the American Agricultural Economics Association