Previous estimates of the land area available for future cropland expansion relied on global-scale climate, soil and terrain data. They did not include a range of constraints and tradeoffs associated with land conversion. As a result, estimates of the global land reserve have been high. Here we adjust these estimates for the aforementioned constraints and tradeoffs.
The water and agriculture glass in Africa is half-empty: Africa has failed to develop its massive water resources and failed to achieve agricultural growth. But the glass is half full, too, as Africa is making a start in building its needed infrastructure and in attracting managerial and knowledge assistance which can help start the needed transformation.
The lost decades for China in the 1950s, 1960s and 1970s look remarkably like the lost decades of Africa in the 1980s and 1990s. Poor land rights, weak incentives, incomplete markets and inappropriate investment portfolios. However, China burst out of its stagnation in the 1980s and has enjoyed three decades of remarkable growth. In this paper we examine the record of the development of China’s food economy and identify the policies that helped generate the growth and transformation of agriculture.
Latin America (LA) has many social indicators similar to those of highly developed economies but most frequently falls midway between least developed countries and industrialized regions. To move forward, LA must address uncontrolled urbanization, agricultural production, social inequity, and destruction of natural resources. We discuss these interrelated challenges in terms of human impact on the nitrogen (N) cycle. Human activity has caused unprecedented changes to the global N cycle; in the past century; total global fixation of reactive N (Nr) has at least doubled.
Although weather data are widely acknowledged to contain measurement errors, the implications of these errors for models that relate weather to yields have not been adequately examined. From statistical theory and applications in many other fields, it is clear that measurement error in a single predictor variable can lead to bias in estimating the effects of that variable, as well as any other correlated predictors.
Statistical studies of rainfed maize yields in the United States and elsewhere have indicated two clear features: a strong negative yield response to accumulation of temperatures above 30 °C (or extreme degree days (EDD)), and a relatively weak response to seasonal rainfall. Here we show that the process-based Agricultural Production Systems Simulator (APSIM) is able to reproduce both of these relationships in the Midwestern United States and provide insight into underlying mechanisms.
Sugarcane area is currently expanding in Brazil, largely in response to domestic and international demand for sugar-based ethanol. To investigate the potential hydroclimatic impacts of future expansion, a regional climate model is used to simulate 5 years of a scenario in which cerrado and cropland areas (~1.1E6 km2) within south-central Brazil are converted to sugarcane. Results indicate a cooling of up to ~1.0°C during the peak of the growing season, mainly as a result of increased albedo of sugarcane relative to the previous landscape.
Field experiments and simulation models are useful tools for understanding crop yield gaps, but scaling up these approaches to understand entire regions over time has remained a considerable challenge. Satellite data have repeatedly been shown to provide information that, by themselves or in combination with other data and models, can accurately measure crop yields in farmers’ fields. The resulting yield maps provide a unique opportunity to overcome both spatial and temporal scaling challenges and thus improve understanding of crop yield gaps.
Successful adaptation of agriculture to ongoing climate changes would help to maintain productivity growth and thereby reduce pressure to bring new lands into agriculture. In this paper we investigate the potential co-benefits of adaptation in terms of the avoided emissions from land use change. A model of global agricultural trade and land use, called SIMPLE, is utilized to link adaptation investments, yield growth rates, land conversion rates, and land use emissions.
Rapid population growth, urbanization and rising incomes will present an unprecedented opportunity for growth of commercial agriculture and agribusiness in coming years. The value of food consumed in urban areas is set to expand by four times to 2030, but given evidence of a continuing decline in competitiveness much of this could be sourced from imports even in countries with an apparent comparative advantage in agriculture.
For decades, earnings from farming in many developing countries, including in Sub-Saharan Africa, have been depressed by a pro-urban and anti-trade bias in own-country policies, as well as by governments of richer countries favoring their farmers with import barriers and subsidies. Both sets of policies reduced global economic welfare and agricultural trade, and almost certainly added to global inequality and poverty and to food insecurity in many low-income countries.
Evaluating the contribution of weather and its individual components to recent yield trends can be useful to predict the response of crop production to future climate change, but different modeling approaches can yield diverging results. We used two common approaches to evaluate the effect of weather trends on maize (Zea mays L.) and wheat (Triticum aestivum L.) production in 12 U.S. counties, and investigate sources of disparities between the two methods.
Currently, more than two-thirds of the population in Africa must leave their home to fetch water for drinking and domestic use. The time burden of water fetching has been suggested to influence the volume of water collected by households as well as time spent on income generating activities and child care. However, little is known about the potential health benefits of reducing water fetching distances.
Genetic improvements in heat tolerance of wheat provide a potential adaptation response to long-term warming trends, and may also boost yields in wheat-growing areas already subject to heat stress. Yet there have been few assessments of recent progress in breeding wheat for hot environments.
Wheat is a staple crop throughout much of India, but in many areas it is commonly sown past the optimum window for yields. Recent technologies, such as adoption of no-till practices or earlier maturing cotton and rice varieties, have enabled some farmers to sow wheat earlier, but repeatable and publicly available measurements of sow date trends are lacking. Here we utilize satellite measurements since 2000 to estimate sow dates over a decade throughout wheat growing areas in India.
Eran Bendavid, Assistant Professor of Medicine at Stanford University provides commentary on nutrition and food policy expert Per Pinstrup-Andersen's presentation and paper on "Food systems and human health and nutrition". The symposium and paper are part of the Center on Food Security and the Environment's Global Food Policy and Food Security Symposium series.
Freshwater scarcity has been cited as the major crisis of the 21st century, but it is surprisingly hard to describe the nature of the global water crisis. We conducted a meta- analysis of 22 coupled human–water system case studies, using qualitative comparison analysis (QCA) to identify water resource system outcomes and the factors that drive them.
Soybean production has become a significant force for economic development in Brazil. It has also received considerable attention from environmental and social non-governmental organizations as a driver of deforestation and land consolidation. While many researchers have examined the impacts of soybean production on human and environmental landscapes, there has been little investigation into the economic and institutional context of Brazilian soybean production or the relationship between soy yields and planted area.
Aquaculture is currently the fastest growing animal food production sector and will soon supply more than half of the world’s seafood for human consumption. Continued growth in aquaculture production is likely to come from intensification of fish, shellfish, and algae production. Intensification is often accompanied by a range of resource and environmental problems. We review several potential solutions to these problems, including novel culture systems, alternative feed strategies, and species choices.
The American Midwest is suffering through the driest summer in decades, and Stanford economist Walter Falcon is watching the corn wither in his fields. He writes how the drought is affecting crops, prices and the livelihoods of his fellow farmers in Iowa.