98 results match your criteria: "Center on Food Security and the Environment[Affiliation]"

Increase in crop losses to insect pests in a warming climate.

Science

August 2018

Department of Earth System Science and the Center on Food Security and the Environment, Stanford University, Stanford, CA 94305, USA.

Insect pests substantially reduce yields of three staple grains-rice, maize, and wheat-but models assessing the agricultural impacts of global warming rarely consider crop losses to insects. We use established relationships between temperature and the population growth and metabolic rates of insects to estimate how and where climate warming will augment losses of rice, maize, and wheat to insects. Global yield losses of these grains are projected to increase by 10 to 25% per degree of global mean surface warming.

View Article and Find Full Text PDF

Background: Rising atmospheric carbon dioxide concentrations are anticipated to decrease the zinc and iron concentrations of crops. The associated disease burden and optimal mitigation strategies remain unknown. We sought to understand where and to what extent increasing carbon dioxide concentrations may increase the global burden of nutritional deficiencies through changes in crop nutrient concentrations, and the effects of potential mitigation strategies.

View Article and Find Full Text PDF

Poor air quality is thought to be an important mortality risk factor globally, but there is little direct evidence from the developing world on how mortality risk varies with changing exposure to ambient particulate matter. Current global estimates apply exposure-response relationships that have been derived mostly from wealthy, mid-latitude countries to spatial population data, and these estimates remain unvalidated across large portions of the globe. Here we combine household survey-based information on the location and timing of nearly 1 million births across sub-Saharan Africa with satellite-based estimates of exposure to ambient respirable particulate matter with an aerodynamic diameter less than 2.

View Article and Find Full Text PDF

The important but weakening maize yield benefit of grain filling prolongation in the US Midwest.

Glob Chang Biol

October 2018

Department of Earth System Science, Center on Food Security and the Environment, Stanford University, Stanford, California.

A better understanding of recent crop yield trends is necessary for improving the yield and maintaining food security. Several possible mechanisms have been investigated recently in order to explain the steady growth in maize yield over the US Corn-Belt, but a substantial fraction of the increasing trend remains elusive. In this study, trends in grain filling period (GFP) were identified and their relations with maize yield increase were further analyzed.

View Article and Find Full Text PDF

Meeting the global food demand of roughly 10 billion people by the middle of the 21st century will become increasingly challenging as the Earth's climate continues to warm. Earlier studies suggest that once the optimum growing temperature is exceeded, mean crop yields decline and the variability of yield increases even if interannual climate variability remains unchanged. Here, we use global datasets of maize production and climate variability combined with future temperature projections to quantify how yield variability will change in the world's major maize-producing and -exporting countries under 2 °C and 4 °C of global warming.

View Article and Find Full Text PDF

International climate change agreements typically specify global warming thresholds as policy targets , but the relative economic benefits of achieving these temperature targets remain poorly understood. Uncertainties include the spatial pattern of temperature change, how global and regional economic output will respond to these changes in temperature, and the willingness of societies to trade present for future consumption. Here we combine historical evidence with national-level climate and socioeconomic projections to quantify the economic damages associated with the United Nations (UN) targets of 1.

View Article and Find Full Text PDF

Aquaculture is anticipated to play an increasingly important role in global food security because it may represent one of the best opportunities to increase the availability of healthy animal protein in the context of resource and environmental constraints. However, the growth and sustainability of the aquaculture industry faces important bottlenecks with respect to feed resources, which may be derived from diverse sources. Here, using a small but representative subset of potential aquafeed inputs (which we selected to highlight a range of relevant attributes), we review a core suite of considerations that need to be accommodated in concert in order to overcome key bottlenecks to the continued development and expansion of the aquaculture industry.

View Article and Find Full Text PDF

Increasing drought and diminishing benefits of elevated carbon dioxide for soybean yields across the US Midwest.

Glob Chang Biol

February 2018

Department of Earth System Science, Center on Food Security and the Environment, Stanford University, Stanford, CA, USA.

Elevated atmospheric CO concentrations ([CO ]) are expected to increase C3 crop yield through the CO fertilization effect (CFE) by stimulating photosynthesis and by reducing stomatal conductance and transpiration. The latter effect is widely believed to lead to greater benefits in dry rather than wet conditions, although some recent experimental evidence challenges this view. Here we used a process-based crop model, the Agricultural Production Systems sIMulator (APSIM), to quantify the contemporary and future CFE on soybean in one of its primary production area of the US Midwest.

View Article and Find Full Text PDF

The growth of finfish in global open-ocean aquaculture under climate change.

Proc Biol Sci

October 2017

Department of Ecology and Evolutionary Biology, Princeton University, 106A Guyot Hall, Princeton, NJ, USA.

Aquaculture production is projected to expand from land-based operations to the open ocean as demand for seafood grows and competition increases for inputs to land-based aquaculture, such as freshwater and suitable land. In contrast to land-based production, open-ocean aquaculture is constrained by oceanographic factors, such as current speeds and seawater temperature, which are dynamic in time and space, and cannot easily be controlled. As such, the potential for offshore aquaculture to increase seafood production is tied to the physical state of the oceans.

View Article and Find Full Text PDF

Temperature increase reduces global yields of major crops in four independent estimates.

Proc Natl Acad Sci U S A

August 2017

Agricultural and Biological Engineering Department, University of Florida, Gainesville, FL 32611;

Article Synopsis
  • Wheat, rice, maize, and soybean together account for two-thirds of human caloric intake, making their production crucial for global food supply.
  • Different studies have shown varying effects of rising global temperatures on these crops, prompting a comprehensive assessment of their yield impacts.
  • Analysis revealed that without CO2 fertilization and effective adaptation, a one-degree increase in global temperature could lower crop yields significantly: wheat by 6.0%, rice by 3.2%, maize by 7.4%, and soybean by 3.1%, highlighting the need for tailored strategies to ensure food security.
View Article and Find Full Text PDF

Satellite-based assessment of yield variation and its determinants in smallholder African systems.

Proc Natl Acad Sci U S A

February 2017

Department of Earth System Science, Stanford University, Stanford CA 94305.

The emergence of satellite sensors that can routinely observe millions of individual smallholder farms raises possibilities for monitoring and understanding agricultural productivity in many regions of the world. Here we demonstrate the potential to track smallholder maize yield variation in western Kenya, using a combination of 1-m Terra Bella imagery and intensive field sampling on thousands of fields over 2 y. We find that agreement between satellite-based and traditional field survey-based yield estimates depends significantly on the quality of the field-based measures, with agreement highest ([Formula: see text] up to 0.

View Article and Find Full Text PDF

It has been suggested that climate change impacts on the electric sector will account for the majority of global economic damages by the end of the current century and beyond [Rose S, et al. (2014) ]. The empirical literature has shown significant increases in climate-driven impacts on overall consumption, yet has not focused on the cost implications of the increased intensity and frequency of extreme events driving peak demand, which is the highest load observed in a period.

View Article and Find Full Text PDF

Opportunity for marine fisheries reform in China.

Proc Natl Acad Sci U S A

January 2017

Center on Food Security and the Environment, Stanford University, Stanford, CA 94305;

China's 13th Five-Year Plan, launched in March 2016, provides a sound policy platform for the protection of marine ecosystems and the restoration of capture fisheries within China's exclusive economic zone. What distinguishes China among many other countries striving for marine fisheries reform is its size-accounting for almost one-fifth of global catch volume-and the unique cultural context of its economic and resource management. In this paper, we trace the history of Chinese government priorities, policies, and outcomes related to marine fisheries since the 1978 Economic Reform, and examine how the current leadership's agenda for "ecological civilization" could successfully transform marine resource management in the coming years.

View Article and Find Full Text PDF

Many of the irrigated spring wheat regions in the world are also regions with high poverty. The impacts of temperature increase on wheat yield in regions of high poverty are uncertain. A grain yield-temperature response function combined with a quantification of model uncertainty was constructed using a multimodel ensemble from two key irrigated spring wheat areas (India and Sudan) and applied to all irrigated spring wheat regions in the world.

View Article and Find Full Text PDF

Sources of variation in under-5 mortality across sub-Saharan Africa: a spatial analysis.

Lancet Glob Health

December 2016

Division of General Medical Disciplines, Center for Health Policy, Stanford University, Stanford, CA, USA; Center for Primary Care and Outcomes Research, Stanford University, Stanford, CA, USA. Electronic address:

Background: Detailed spatial understanding of levels and trends in under-5 mortality is needed to improve the targeting of interventions to the areas of highest need, and to understand the sources of variation in mortality. To improve this understanding, we analysed local-level information on child mortality across sub-Saharan Africa between 1980-2010.

Methods: We used data from 82 Demographic and Health Surveys in 28 sub-Saharan African countries, including the location and timing of 3·24 million childbirths and 393 685 deaths, to develop high-resolution spatial maps of under-5 mortality in the 1980s, 1990s, and 2000s.

View Article and Find Full Text PDF

Reliable data on economic livelihoods remain scarce in the developing world, hampering efforts to study these outcomes and to design policies that improve them. Here we demonstrate an accurate, inexpensive, and scalable method for estimating consumption expenditure and asset wealth from high-resolution satellite imagery. Using survey and satellite data from five African countries--Nigeria, Tanzania, Uganda, Malawi, and Rwanda--we show how a convolutional neural network can be trained to identify image features that can explain up to 75% of the variation in local-level economic outcomes.

View Article and Find Full Text PDF

Climate change can reduce crop yields and thereby threaten food security. The current measures used to adapt to climate change involve avoiding crops yield decrease, however, the limitations of such measures due to water and other resources scarcity have not been well understood. Here, we quantify how the sensitivity of maize to water availability has increased because of the shift toward longer-maturing varieties during last three decades in the Chinese Maize Belt (CMB).

View Article and Find Full Text PDF

Growing evidence demonstrates that climatic conditions can have a profound impact on the functioning of modern human societies, but effects on economic activity appear inconsistent. Fundamental productive elements of modern economies, such as workers and crops, exhibit highly non-linear responses to local temperature even in wealthy countries. In contrast, aggregate macroeconomic productivity of entire wealthy countries is reported not to respond to temperature, while poor countries respond only linearly.

View Article and Find Full Text PDF

Large-scale monitoring of crop growth and yield has important value for forecasting food production and prices and ensuring regional food security. A newly emerging satellite retrieval, solar-induced fluorescence (SIF) of chlorophyll, provides for the first time a direct measurement related to plant photosynthetic activity (i.e.

View Article and Find Full Text PDF

The shifting influence of drought and heat stress for crops in northeast Australia.

Glob Chang Biol

November 2015

CSIRO Agriculture Flagship, Queensland Bioscience Precinct, St Lucia, QLD, 4067, Australia.

Characterization of drought environment types (ETs) has proven useful for breeding crops for drought-prone regions. Here, we consider how changes in climate and atmospheric carbon dioxide (CO2 ) concentrations will affect drought ET frequencies in sorghum and wheat systems of northeast Australia. We also modify APSIM (the Agricultural Production Systems Simulator) to incorporate extreme heat effects on grain number and weight, and then evaluate changes in the occurrence of heat-induced yield losses of more than 10%, as well as the co-occurrence of drought and heat.

View Article and Find Full Text PDF

Does aquaculture add resilience to the global food system?

Proc Natl Acad Sci U S A

September 2014

Center for Economic Research and Tilburg Sustainability Center, Tilburg University, 5000 LE, Tilburg, The Netherlands.

Aquaculture is the fastest growing food sector and continues to expand alongside terrestrial crop and livestock production. Using portfolio theory as a conceptual framework, we explore how current interconnections between the aquaculture, crop, livestock, and fisheries sectors act as an impediment to, or an opportunity for, enhanced resilience in the global food system given increased resource scarcity and climate change. Aquaculture can potentially enhance resilience through improved resource use efficiencies and increased diversification of farmed species, locales of production, and feeding strategies.

View Article and Find Full Text PDF

Greater sensitivity to drought accompanies maize yield increase in the U.S. Midwest.

Science

May 2014

Department of Environmental Earth System Science and Center on Food Security and the Environment, Stanford University, Stanford, CA 94305, USA.

A key question for climate change adaptation is whether existing cropping systems can become less sensitive to climate variations. We use a field-level data set on maize and soybean yields in the central United States for 1995 through 2012 to examine changes in drought sensitivity. Although yields have increased in absolute value under all levels of stress for both crops, the sensitivity of maize yields to drought stress associated with high vapor pressure deficits has increased.

View Article and Find Full Text PDF

The influence of climate change on global crop productivity.

Plant Physiol

December 2012

Department of Environmental Earth System Science and Center on Food Security and the Environment, Stanford University, Stanford, California 94305, USA.

View Article and Find Full Text PDF