A critical question for agricultural production and food security is how water demand for staple crops will respond to climate and carbon dioxide (CO2) changes1, especially in light of the expected increases in extreme heat exposure2. To quantify the trade-offs between the effects of climate and CO2 on water demand, we use a ‘sink-strength’ model of demand3,4 which relies on the vapour-pressure deficit (VPD), incident radiation and the efficiencies of canopy-radiation use and canopy transpiration; the latter two are both dependent on CO2. This model is applied to a global data set of gridded monthly weather data over the cropping regions of maize, soybean, wheat and rice during the years 1948–2013. We find that this approach agrees well with Penman–Monteith potential evapotranspiration (PM) for the C3 crops of soybean, wheat and rice, where the competing CO2 effects largely cancel each other out, but that water demand in maize is significantly overstated by a demand measure that does not include CO2, such as the PM. We find the largest changes in wheat, for which water demand has increased since 1981 over 86% of the global cropping area and by 2.3–3.6 percentage points per decade in different regions.
Policies that promote biofuels in major agricultural economies raise important questions for food prices and food security at local to global scales. Global biofuel output rose from 38 billion liters to 131 billion liters between 2005 and 2015, boosting the demand for annual- and perennial-crop feedstocks such as maize, sugar, soy, rapeseed, and palm oil. Although ethanol volume was three times that of biodiesel in 2015, the share of biodiesel in total biofuel output rose from 10% to almost 25% over the course of the decade (EIA, n.d.; REN21, 2016). Biodiesel production increased 700% between 2005 and 2015 and is expected to rise by another 35% by 2025 (OECD/FAO, 2014). In this paper, we examine the linkages between biodiesel, oil crop, and energy markets, and ask: What are the food security implications of biodiesel policies in major agricultural economies? How do governments adjust biodiesel policies in response to international commodity prices, trade opportunities, and their changing economic and environmental priorities?
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Global Food Security
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Rosamond L. Naylor
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The rise in global biodiesel production: Implications for food security
Food security experts identify government support, policy implementation, private sector engagement and investment in smallholder farmers as keys to Africa’s agricultural future.
Food security experts from the Alliance for a Green Revolution in Africa (AGRA) gathered to discuss transforming food production in Africa at Stanford on Nov. 29. The symposium, hosted by the Center on Food Security and the Environment (FSE) examined the challenges, strategies, and possible solutions for catalyzing and sustaining an inclusive agriculture transformation in Africa.
Moderator Ertharin Cousin, FSE visiting fellow and previous World Food Programme director with more than 25 years of experience on hunger, food, and resilience strategies, launched the panel by outlining Africa’s plight. “Today some 100 million of the farmers across Sub-Saharan Africa farm less than 2 hectares of land. Some 80 percent of those living in rural areas are poor. More than 30 percent of the rural population is chronically hungry and 35 percent of the under-five-year-olds are stunted. By 2050, the bulk of the world's population growth will take place on the continent. In fact, some project that 1.3 billion will be added to the continent, and Nigeria’s [population] will grow larger than the size of the United States between now and 2050,” Cousin said
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While Africa continues to experience the highest occurrence of food insecurity worldwide, the continent also contains over 60 percent of the worlds uncultivated but fertile land. AGRA formed in 2006 to fulfill the vision that Africa can feed itself and the world. Panelists included Agnes Kalibata, AGRA President and former Minister of Agriculture and Animal Resources of Rwanda; Kanayo F. Nwanze, AGRA board member and immediate past president of the International Fund for Agricultural Development; Usha Barwale Zehr, AGRA board member and Director and Chief Technology Officer of Maharashtra Hybrid Seeds Company Private Limited; and Rajiv Shah, AGRA board member, Rockefeller Foundation President and former Administer of USAID.
Kanayo F. Nwanze stressed the importance of agricultural transformation for Africa’s future. “No country in the world ever transformed itself without going through an agrarian change. No country. Europe, 17th; Japan, 18th century; 19th century was the US, your country; China, 20th century. Why should they be different from Africa? So, first and foremost, we have to have total agricultural transformation,” Nwanze said.
AGRA president, Agnes Kalibata, also spoke to the need for policy implementation and government support in helping drive change. “AGRA as an institution can only do so much. But these governments have the potential and the capacity to reach every corner of their countries. The problem is they are challenged by capacity to do that, by capacity to design proper programs, and by capacity to implement these programs,” Kalibata said.
Expanding on governments' ability to impact and drive change, Usha Barwale Zehr highlighted Asia’s success, specifically with strategic partnerships. “…we've done a lot of talking about public/private partnership. Not so much on the ground on implementing it in a manner, which happened in Asia, for instance, where there was policy, and, most importantly, government will. The government was willing to do whatever it took to make sure that agriculture was transformed at the end of it,” Zehr said.
Beyond government and policy support the panelists also addressed the need for innovation and access to seed technologies. “Why is it that the African farmer and the Indian farmer should not have access to what the American farmer has access to today and reaps benefit from it? …So it's the hybrids, the varieties, the GM technology. Tomorrow it'll be the gene-edited products. And after that we will talk about the satellite-based imaging data that we will use for developing drought-tolerant crops for that very, very small micro environment that existed in the one district in Nigeria,” Zehr said.
"By 2050, who is going to feed Africa? … It's the youth of today. But they're not going to be using the same technologies that exist today. Just think of what IT can do, aggregation, organization of farmer's groups. So, the elements are there. I see the agriculture of tomorrow meeting the challenge – for Africa meeting that challenge is Africa being at the forefront of feeding the world. Africa has to be able to feed itself first. And we have all the opportunities there,” Nwanze said.
This is the first installment of the Global Food Security Symposium series hosted by Stanford University's Center on Food Security and the Environment and generously supported by Zach Nelson and Elizabeth Horn. FSE is a joint initiative of the Stanford Woods Institute for the Environment and the Freeman Spogli Institute for International Studies.
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Panel members at the Global Food Security Symposium, Nov. 29 2017.
Stanford’s Center on Food Security and the Environment launches new symposium series focused on global food security with panel exploring Africa’s agricultural potential.
Organized by the Center on Food Security and the Environment (FSE), the Nov. 29 symposium is the first in the center’s new Global Food Security Symposium series. Panel members include visiting AGRA board members, who will examine the challenges, strategies, and possible solutions for catalyzing and sustaining an inclusive agriculture transformation in Africa. This symposium marks the third series established by FSE convening thought leaders addressing global food security issues.
Afflicted by conflict, political upheaval, and extreme weather patterns Africa continues to experience the highest occurrence of food insecurity. However, with over 60 percent of the worlds uncultivated but fertile land, there is significant room for improvement. AGRA formed in 2006 to fulfill the vision that Africa can feed itself and the world. As an alliance led by Africans with roots in farming communities across the continent, they work to understand the unique needs of farmers and offer sustainable solutions designed to boost production.
In a region with 27.4 percent of the population currently experiencing food insecurity, creating a sustainable agricultural revolution remains a key solution to improving food security across the area. Moderated by Ertharin Cousin, previous World Food Programme director, with 25 years of experience on hunger, food, and resilience strategies, the panel will explore how an agricultural transformation in Africa can sustain a growing population, relieve hunger, generate jobs, improve social cohesion, and create global exports.
Panel members include: Ertharin Cousin (moderator), Payne Distinguished Lecturer at the Freeman Spogli Institute for International Studies and Visiting Fellow at the Center on Food Security and the Environment, former US Ambassador to the UN Agencies for Food and Agriculture in Rome.
Agnes Kalibata, the President of AGRA and former Minister of Agriculture and Animal Resources of Rwanda.
Kanayo F. Nwanze, the immediate past president of the International Fund for Agricultural Development (IFAD), winner of the Africa Food Prize in 2016, AGRA board member.
Rajiv Shah, Rockefeller Foundation President, former Administer of USAID (2010-15) where he led bipartisan reform and expansion of US efforts combating global food insecurity. During his previous work at the Gates Foundation he helped launched AGRA.
Usha Barwale Zehr, Director and Chief Technology Officer at Maharashtra – one of India’s largest and most successful multinational seed companies – and AGRA board member.
This is the first installment of the Global Food Security Symposium series hosted by Stanford University's Center on Food Security and the Environment and generously supported by Zach Nelson and Elizabeth Horn. FSE is a joint initiative of the Stanford Woods Institute for the Environment and the Freeman Spogli Institute for International Studies.
Elevated atmospheric CO2 concentrations ([CO2]) are expected to increase C3 crop yield through the CO2 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. APSIM accurately reproduced experimental data from the Soybean Free-Air CO2 Enrichment site showing that the CFE declined with increasing drought stress. This resulted from greater radiation use efficiency (RUE) and above-ground biomass production at elevated [CO2] that outpaced gains in transpiration efficiency (TE). Using an ensemble of eight climate model projections, we found that drought frequency in the US Midwest is projected to increase from once every 5 years currently to once every other year by 2050. In addition to directly driving yield loss, greater drought also significantly limited the benefit from rising [CO2]. This study provides a link between localized experiments and regional-scale modeling to highlight that increased drought frequency and severity pose a formidable challenge to maintaining soybean yield progress that is not offset by rising [CO2] as previously anticipated. Evaluating the relative sensitivity of RUE and TE to elevated [CO2] will be an important target for future modeling and experimental studies of climate change impacts and adaptation in C3 crops.
Food security will be increasingly challenged by climate change, natural resource degradation, and population growth. Wheat yields, in particular, have already stagnated in many regions and will be further affected by warming temperatures. Despite these challenges, wheat yields can be increased by improving management practices in regions with existing yield gaps. To identify the magnitude and causes of current yield gaps in India, one of the largest wheat producers globally, we produced 30 meter resolution yield maps from 2001 to 2015 across the Indo-Gangetic Plains (IGP), the nation's main wheat belt. Yield maps were derived using a new method that translates satellite vegetation indices to yield estimates using crop model simulations, bypassing the need for ground calibration data. This is one of the first attempts to apply this method to a smallholder agriculture system, where ground calibration data are rarely available. We find that yields can be increased by 11% on average and up to 32% in the eastern IGP by improving management to current best practices within a given district. Additionally, if current best practices from the highest-yielding state of Punjab are implemented in the eastern IGP, yields could increase by almost 110%. Considering the factors that most influence yields, later sow dates and warmer temperatures are most associated with low yields across the IGP. This suggests that strategies to reduce the negative effects of heat stress, like earlier sowing and planting heat-tolerant wheat varieties, are critical to increasing wheat yields in this globally-important agricultural region.
Although development organizations agree that reliable access to energy and energy services—one of the 17 Sustainable Development Goals—is likely to have profound and perhaps disproportionate impacts on women, few studies have directly empirically estimated the impact of energy access on women's empowerment. This is a result of both a relative dearth of energy access evaluations in general and a lack of clarity on how to quantify gender impacts of development projects. Here we present an evaluation of the impacts of the Solar Market Garden—a distributed photovoltaic irrigation project—on the level and structure of women's empowerment in Benin, West Africa. We use a quasi-experimental design (matched-pair villages) to estimate changes in empowerment for project beneficiaries after one year of Solar Market Garden production relative to non-beneficiaries in both treatment and comparison villages (n = 771). To create an empowerment metric, we constructed a set of general questions based on existing theories of empowerment, and then used latent variable analysis to understand the underlying structure of empowerment locally. We repeated this analysis at follow-up to understand whether the structure of empowerment had changed over time, and then measured changes in both the levels and likelihood of empowerment over time. We show that the Solar Market Garden significantly positively impacted women's empowerment, particularly through the domain of economic independence. In addition to providing rigorous evidence for the impact of a rural renewable energy project on women's empowerment, our work lays out a methodology that can be used in the future to benchmark the gender impacts of energy projects.
Large-scale crop monitoring and yield estimation are important for both scientific research and practical applications. Satellite remote sensing provides an effective means for regional and global cropland monitoring, particularly in data-sparse regions that lack reliable ground observations and reporting. The conventional approach of using visible and near-infrared based vegetation index (VI) observations has prevailed for decades since the onset of the global satellite era. However, other satellite data encompass diverse spectral ranges that may contain complementary information on crop growth and yield, but have been largely understudied and underused. Here we conducted one of the first attempts at synergizing multiple satellite data spanning a diverse spectral range, including visible, near-infrared, thermal and microwave, into one framework to estimate crop yield for the U.S. Corn Belt, one of the world's most important food baskets. Overall, using satellite data from various spectral bands significantly improves regional crop yield predictions. The additional use of ancillary climate data (e.g. precipitation and temperature) further improves model skill, in part because the crop reproductive stage related to harvest index is highly sensitive to environmental stresses but they are not fully captured by the satellite data used in our study. We conclude that using satellite data across various spectral ranges can improve monitoring of large-scale crop growth and yield beyond what can be achieved from individual sensors. These results also inform the synergistic use and development of current and next generation satellite missions, including NASA ECOSTRESS, SMAP, and OCO-2, for agricultural applications.
Casey Maue, a PhD student in the Emmett Interdisciplinary Program in Environment and Resources alogn with Woods Institute Senior Fellow, Erica Plambeck, spent time this spring examining the oil palm supply chain in Ghana. Casey is a 3rd year PhD student and is advised by FSE Director Roz Naylor and FSE Senior Fellow Marshall Burke. Casey's research focuses on the economic dimensions of agricultural development in Sub-Saharan Africa, and the economic impacts of climate change on the agricultural sector. In his dissertation chapter focused on development in the oil palm industry in Ghana, Casey is examining how the provision of informal financial services (such as access to trade credit or informal savings) by different buyers (processors) in the oil palm supply chain determines farmers' output-market decisions, and how relational contracts between farmers and processors that provide access to these informal services can be leveraged to increase supply chain productivity, and the welfare of smallholder oil palm farmers.
Casey and Erica traveled to the municipality of Juaben, located in the Ashanti region of central Ghana, and conducted focus group discussions and in-person interviews with numerous stakeholders working in oil palm. They visited with oil palm farmers and buyers of their fruit – palm oil processors. There are two kinds of palm oil processors in the Ghanaian supply chain, small-scale artisanal mills and larger industrial mills, which compete with each other for the fruit produced by smallholder oil palm farmers. Through this research, Casey and Erica sought to better understand the economic forces that affect a farmer’s decision to sell their fruit to an industrial versus an artisanal mill. Doing so will provide insights that processors can use to design more effective incentives for their suppliers that will increase the quantity and reliability of fruit delivered to them. Fostering more consistent, and trusting relationships between farmers and processors is key to increasing the productivity and profitability of enterprises all along the supply chain, to increasing food security for poor oil palm farmers, and to promoting effective private governance of oil palm’s environmental impacts.
Since the 1960s, India’s groundwater irrigation has increased dramatically, playing an important role in its economy and people’s lives — supporting livelihoods of over 26 crore farmers and agricultural labourers who grow over a third of India’s foodgrains. These benefits, however, have come at the cost of increased pressure on groundwater reserves.
India is the world’s largest user of groundwater and, since the 1980s, its groundwater levels have been dropping. The severity of the problem is particularly acute in the northwest, where levels have plunged from 8m below ground to 16m, so that water needs to be pumped from even greater depths. Worse yet, much of this is non-renewable since recharge rates are less than extraction rates and replenishing this resource can take thousands of years.
This won’t last
Using up such “fossil” groundwater is unsustainable. Moreover, the future of monsoon rainfall remains uncertain; while some climate models predict an increase, others forecast a weakening monsoon, although changes in monsoon variability are already underway and will continue into the future. Historical records show the number of dry spells and the intensity of wet spells have risen over the past 50 years. As climate change alters the monsoon, the large stresses on India’s groundwater resources may increase.
