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A Sustainability Challenge: Food Security for All: Report of Two Workshops (2012)

Chapter: [Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES

« Previous: PART II: EXPLORING SUSTAINABLE SOLUTIONS FOR INCREASING GLOBAL FOOD SUPPLIES--INTRODUCTION
Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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1

ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES

The first segment of the second workshop focused on the challenges and opportunities for achieving sustainable food security. The session began with a summary from workshop one, examining the methodologies in use to measure food and nutritional security as well as to describe key natural resources essential for assuring the sustainability of global agricultural production. Subsequent speakers talked about the need for new agricultural paradigms; trends in agricultural productivity; and key natural resource constraints, including water, land and forests, biodiversity, and soils. There was also a session examining the likely impact of climate change on future food production and related risks and vulnerabilities. Each session was followed by a brief question and answer period.

CURRENT AND EXPECTED FUTURE FOOD AND NUTRITION SECURITY1

Hartwig de Haen, University of Göttingen

Summary Points from Workshop One

The first National Academies workshop (“Measuring Food Insecurity and Assessing the Sustainability of Global Food Systems”) discussed the various types of methodology currently in use to measure indicators of food and nutrition security. Most participants noted that the current methods do not provide fully satisfactory indicators. They often differ considerably with regard to magnitude, trends and geographical distribution of hunger in the world. de Haen noted that specific proposals were suggested for improvements of all three key methods, the Undernourishment indicator based on Food Balance Sheets (FBS), household consumption surveys and anthropometry.

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1 The presentation is available at http://sites.nationalacademies.org/PGA/sustainability/foodsecurity/PGA_062564, presentation by Hartwig de Haen (May 2, 2011).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Enough Is Known to Call for Urgent Action against Hunger

Although we may not know the numbers of food insecure and malnourished with a high degree of accuracy, it appears safe to characterize the current state of food and nutrition insecurity as follows:

  • Many developing countries are currently experiencing a nutrition transition. Lifestyles are becoming more urban and sedentary, with foods and drinks being more energy-dense and diets containing more processed foods, sugars, fats and animal products (Pinstrup-Andersen, 2010). The result is a triple burden of malnutrition: one part of the population is still undernourished; many also suffer from deficits of specific nutrients, in particular micronutrients; and others are overweight.
  • Close to a billion people are chronically undernourished. While subject to possible estimation errors, the FAO (Food and Agriculture Organization of the United Nations) indicator of 850 million undernourished persons in 2005/2007 seems to be a realistic order of magnitude. First, the estimate is still lower than the number of absolutely poor (people living on less than $1.25 per day), which the World Bank estimated at 1.4 billion in 2005 (Ravallion, 2011). Secondly, FAO’s estimates are compiled using rather low rates of intra-national inequality of food availability. Many household consumption surveys show significantly higher coefficients of variation.
  • More than 2 billion people are suffering from various forms of micronutrient deficiency. This estimate is again likely to be conservative as many people are deficient in more than one nutrient.
  • Almost 30 percent of children under five in developing countries are underweight. Underweight is a summary indicator combining acute and persistent causes of child malnutrition. The prevalence is high but has declined during the last decade, in particular in Asia and the Pacific (UNICEF). Malnutrition is directly or indirectly associated with almost half of the 9 million child deaths per year worldwide, with the highest rates in Sub-Saharan Africa.
  • According to WHO, 1.5 billion adults are overweight. Nearly 43 million children under five were overweight in 2010 (WHO, 2011). 65 percent of the world’s population live in countries where overweight and obesity kills more people than underweight (Uauy, 2011). These numbers underscore the fact that action is needed to fight undernourishment as well as overnourishment.
  • Unless decisive action is taken, the number of hungry may continue to increase with rising food prices and market volatility. Agricultural supply growth is not enough to bring hunger down (FAO, 2009). What matters is that the modalities of supply growth benefit the poor (“agriculture for development”) (World Bank, 2007).
Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

Addressing Future Problems of Food and Nutrition Security—A Double Goal

de Haen stated that there is now broad agreement among experts that to achieve the nutrition related Millennium Development Goals (MDGs) and ultimately food and nutrition security for all requires pursuing a double goal: (1) Alleviate hunger and malnutrition on a sustainable basis and (2) Create conditions for meeting the increasing demand of a growing world population.

Alleviating Hunger and Malnutrition

Addressing this first goal requires a strategy with three entry points:

(1) Giving the poor better access to income earning opportunities. The experience of successful countries shows that public investment in rural areas, in particular investments benefitting smallholder agriculture, generates greater reduction of poverty than does investment in non-agriculture sectors. The majority of the poor still lives in rural areas. With further urbanization, more action against hunger will be needed in cities as well.

(2) Social safety nets. There is now a wide array of practical experiences with social safety nets,2 which provide the neediest persons immediate access to vital social services, including food assistance, health and sanitation, education and training. In the absence of social protection, each reoccurrence of a crisis will force the poorest into unsustainable and often detrimental coping strategies.

(3) Targeted nutrition improvement measures. These may range from fortification of certain foods in some countries to training for life course approaches to address obesity risks in others.

Meeting the Growing Demand

de Haen explained that the second strategic goal requires ensuring future production growth to meet the demand of a growing and increasingly prosperous world population.3 Whether or not the world-wide food system will succeed in meeting that growing demand on a sustainable basis will depend on the effective interplay of a number of driving factors. The most important ones are listed below.

Population growth: According to the medium variant of the 2008 UN population projection, the world population is expected to reach 9.3 billion by the year 2050. More than two thirds of that population will be urban, compared with 50 percent today. Nearly the entire increase will occur in today’s developing countries, with the largest increase in Asia.

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2 See, for example, B. Guha-Khasnobis, S. S. Acharya, and B. Davis (Eds.) 2007. Food Insecurity, Vulnerability and Human Rights Failure. UNU-Wider.

3 Production growth is also needed to enable today’s almost one billion undernourished to increase consumption to the minimum requirements. Depending on the food gap to be filled, this would require between 30 and 50 million tons of grain equivalents, hence a small fraction of today’s total supplies.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Income growth: According to the World Bank, “In most developing countries, GDP has regained levels that would have prevailed had there been no boom-bust cycle” (World Bank, 2011). With this prospect, the developing countries, especially in Asia, but also in Central and Eastern Europe and in many countries of Sub-Saharan Africa, are expected to resume their strong economic growth.

Demand growth: The projected population and income growth are likely to translate into strong growth of per caput demand for agricultural products. However, some of the more populous countries like China and Brazil are moving towards saturation levels. Thus the gradual slowdown of overall demand growth is likely to continue. According to FAO’s projection to 2050, published in 2009, global demand for agricultural products is expected to grow by about 70 percent compared to 2005/2007.4

Resource constraints, climate change and sustainable intensification: The task ahead is daunting considering the multiple resource constraints. Until 2050, the area of agricultural crop land per person is likely to decline further; already today, 1.4 billion people are living in areas with declining ground water levels (World Bank, 2007), two thirds of the agricultural ecosystems are more or less degraded, the genetic resource base for future plant breeding is faced by various risks, and the burden of adjustment to climate change falls disproportionately on the rural areas of the southern hemisphere. In view of these resource constraints, about 80 percent of the projected supply growth will have to originate from sustainable intensification (i.e., productivity growth that minimizes negative environmental implications, contributes positive environmental services and is generally integrated into an ecosystems approach) (Bruinsma, 2009).

Reducing waste and losses: In the light of the constraints to natural resources, efforts to reduce waste and losses should be seriously considered. According to various sources, waste and spoilage causing useless input of land, water, feed and energy could be in the order of 30 to 40 percent of agricultural production world-wide.5

Trade and market structure: Even with high growth of their own production, the developing countries as a group will face a significant widening of their net trade deficit for basic food stuffs—enhancing export opportunities for agriculture of developed countries. This perspective will make it even more important that trade rules and market structures enable poorer countries to generate export surpluses in other goods and services, including tropical products.

Perspectives for Reduction of Hunger and Malnutrition

Both main organizations with long term projections of world agriculture, FAO and IFPRI, include food security indicators in their projections. These are generated on the basis of certain assumptions regarding future changes in the intra-country inequality of access to food. While FAO’s projections use the same indicator (undernourishment) that is used to monitor past

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4 Provisional estimate made in mid-2009 (Bruinsma, 2009) indicated 70 percent. This was based on projections to 2050 made in 2003-2005 (FAO, 2006). Work in FAO underway for updating the projections.

5 According to sources cited by UNEP, even “57 percent of the potential edible crop harvest was lost during different stages of conversion from crop to food or as food waste” (UNEP Brief, undated, “Agriculture, a Catalyst for Shifting to a Green Economy”).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

food security, IFPRI uses child underweight as an indicator of malnutrition. According to FAO’s latest projection (Alexandratos, 2009), using one trajectory considered most realistic, undernourishment is expected to decline. The decline is rather slow, so that the target of halving the number of undernourished between 1990/1992 and 2015, set by the World Food Summit in 1996, will be achieved only just before 2050. IFPRI’s projections also indicate a decline in malnutrition. It shows in various scenarios the importance of economic development in reducing child malnutrition. In an optimistic scenario, the number of malnourished children in developing countries falls by almost 46 percent between 2010 and 2050. Child malnutrition would fall even under a pessimistic scenario, though by only 2 percent. These perspectives imply a reversal of the recent trend of rising chronic hunger. de Haen explained that none of the studies considers explicitly how alternative policies, including both production and consumption related policies, would be effective in changing that trend.

Conclusion—Main Challenges

Effective reduction of food and nutrition insecurity requires a deliberate double effort: One is action to improve the access to income earning opportunities for today’s hungry and to ensure social protection, including immediate access to food for the neediest. The other is investment in sustainable, longer-term agricultural growth and development. Action and behavioral change will be needed at all levels—individual, corporate, and public. Governments in all countries also have a key responsibility in establishing the enabling conditions for effective and sustainable improvements, within a framework of political stability and good governance. They must have the political will to change priorities, mobilize public investment and reform institutions in favor of sustainable food and nutrition security. de Haen stated that a guiding principle must be combining measures to reduce hunger with investment in sustainable growth of food supplies. In many countries, this will require a focus on rural smallholders, representing the majority of the poor, but it must increasingly also address urban food security problems.

AGRICULTURAL PRODUCTIVITY AND NATURAL RESOURCE ENDOWMENTS6

Philip Pardey, University of Minnesota

Philip Pardey opened this session of the workshop by raising a number of critical questions—what are past and prospective rates of agricultural productivity growth, how do these rates relate to changes in demand, how have natural resource endowments changed over time, and what are the links between the flows of natural input services to and from agriculture? He suggested that there were three key indicators associated with agricultural productivity—what is produced, where it is produced, and how it is produced. Moreover, the biological processes that

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6 The presentation is available at http://sites.nationalacademies.org/PGA/sustainability/foodsecurity/PGA_062564, presentation by Philip Pardey (May 2, 2011).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

underpin production agriculture underscore the need for a spatially sensitive view of production, given spatial variation in the natural inputs that are distinctively used in agriculture.

Pardey stressed the importance of understanding past and likely future trends in agricultural productivity relative to corresponding changes in the demand for agricultural outputs, since differential rates of supply (productivity) and demand growth will cause agricultural commodity prices to change over time, with direct hunger and poverty consequences. He also explained that if U.S. agricultural productivity had not increased substantially between 1900 and 2008, an area equivalent to the entire area east of the Mississippi would have had to be cultivated to reach the level of cereal production attained in 2008, with far reaching natural resource consequences.

Pardey noted two sets of important drivers of productivity change that are typically ignored by traditional productivity measurements: (1) natural inputs, such as weather, terrain, and soil types, and (2) pests and diseases. All of these natural inputs vary across time and space, making it difficult to identify the degree to which these factors account for measured variation in agricultural productivity vis-à-vis the effects of other factors, including differences in the scale (and structure) of production and unmeasured changes in the quality of conventional inputs (such as land, labor and capital). He also emphasized the important productivity consequences of technological changes arising from investments in public and private agricultural research and development (R&D). However, the agricultural productivity consequences of R&D and changes in the natural resource base play out over many decades, adding to the difficulty of attributing measured changes in productivity to either of these (or other) factors. For example, almost 60 years passed from the conception of hybrid corn to its commercial release.

There are alternative, conventional measures of productivity, be they partial-, total- or multi-factor measures.7 Consider crop yields, for example, as one seemingly straightforward and illustrative partial-factor productivity measure. Figure II 1-1 illustrates the difficulties in measuring and understanding differences among countries in average crop yields. The figure shows pixilated crop yields (on a five arc-minute grid) worldwide for four crops, with production areas stratified into yield deciles (1 being areas with the lowest 10 percent of yields worldwide, and 10 representing areas with the highest yields). The inset table indicates that in 2000 the United States accounted for 32 percent of the world’s corn pixels that fall in the three highest yielding deciles, while Africa accounts for only 2.5 percent of such high-yielding pixels.

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7 As Alston, Babcock and Pardey (2010, p. 452) observed, “Individual grain yield is an example of a partial factor productivity (PFP) measure. It is ‘‘partial’ in the sense that it only accounts for changes in the amount of land used in production. It does not account for changes in the quantities of other inputs—such as labor, capital, fertilizer, rainfall, or irrigation—that also affect production. Thus yield and other partial measures can be seen as partial with respect to their treatment of outputs as well as inputs. At the opposite end of the spectrum are measures of total factor productivity (TFP), the aggregate quantum of all outputs divided by the aggregate quantum of all of the inputs used to produce those outputs. TFP is a theoretical concept. All real-world measures omit at least some of the relevant outputs and some of the relevant inputs, and therefore it is more accurate to refer to the real-world measures as multifactor productivity (MFP) measures.”

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

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FIGURE II 1-1 Spatial Distribution of Crop Yields, 2000 (SPAM ver 3.0)

SOURCE: Presentation by Philip Pardey, University of Minnesota, May 2, 2011.

Each of these pixels is associated with a set of natural resource attributes (in terms of rainfall, soil nutrients and organic matter, temperature, sunlight, and so on), and to the extent that these natural attributes affect crop yields, differences in the spatial location of production within the United States versus Sub-Saharan Africa will also affect crop yields. But these natural attributes are rarely measured, thereby confounding our interpretation of the sources of productivity (yield) differences among countries. Thus, in this instance, to what extent do differences in (unmeasured) natural inputs between the United States and Sub-Saharan Africa account for differences in average corn yields versus differences, say, in the amount, nature and effectiveness of R&D in these two areas of the world? Moreover, to the extent that the location of production within a country changes over time (and thereby the implicit mix of natural inputs), the problem of disentangling the productivity consequences of natural inputs from other factors is made doubly difficult.

Meaningful advances in our state of understanding about the nexus between natural resources and agricultural productivity are likely to hinge on at least two fundamental factors. First is the need for a spatially explicit view of agricultural production processes given the spatial variation in the biological processes that define production agriculture. Second is the need to take a long-run perspective, likely decades rather than years, given the timeframes it typically takes for natural input cum agricultural productivity processes to play out.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

ARE NEW PARADIGMS NEEDED FOR SUSTAINABLE FOOD SECURITY IN THE FACE OF UNCERTAINTIES AND RISKS?8

Marco Ferroni, Syngenta Foundation for Sustainable Agriculture

The world’s food security is under threat because of the “double squeeze” on productive capacity, which stems from rapid demand growth and a deteriorating natural resource base, which is increasingly unpredictable due to climate change. The average annual rate of growth of cereal yields has declined from more than 3 percent in the 1980s to close to 1 percent in recent years, a level just below the rate of population growth. There is little room in this situation for the food system as a whole to absorb income growth-induced additions to demand or accommodate production shortfalls due to adverse weather. Prices had to (and did) rise, and they became more volatile as markets adjusted to such factors as changes in grain stocks relative to use, export restrictions, currency movements, fluctuations in the price of oil, financial speculation and subsidies for biofuels that added to the demand for commodities that competed with food for land and water. Globally speaking, agriculture is under stress. For this reason, many analysts and observers have remarked that, as we look to the future, “business as usual” in agriculture will not suffice.

The world needs to grow more food, in addition to taking other measures such as the reduction of post-harvest losses and waste in the supply chain. This will require new models and approaches. Going forward, the production-based approach of the Green Revolution that sought cheap and abundant supplies of food is no longer comprehensive enough. The needed increases in food production must be brought about sustainably, using natural resources wisely to be able to “indefinitely meet the requirements for food, feed and fiber at socially acceptable economic and environmental cost” (Crosson, 1992). Increases in food production can come from agricultural intensification, the expansion of the agricultural frontier, or a combination of the two. Although there are untapped reserves of land and water, to be sure (mostly in Sub-Saharan Africa, Latin America, Eastern Europe and Central Asia), most of the required growth in global production is going to have to come from intensification, because land and water are finite assets already overused in many places.

Sustainable intensification can be defined as “producing more output from the same area of land while reducing the negative environmental impacts and at the same time increasing contributions to natural capital and the flow of environmental services” (Pretty, 2011). These are requirements with many implications, but the place to start is yield. Yield gaps are huge in many settings as shown in Figure II 1-2.9 They need to be reduced and closed as part of intensification. Reducing yield gaps will also raise the efficiency of water use.10 It has been shown that in grains and other field crops, the correlation between water use efficiency and yield per unit of land is high.

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8 The presentation is available at http://sites.nationalacademies.org/PGA/sustainability/foodsecurity/PGA_062564, presentation by Marco Ferroni (May 2, 2011).

9 Yield gap can be defined as the difference between realized productivity and the best that can be achieved with current genetic material and available technologies and management.

10 Liters of water used to produce a unit of grain.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

The literature on yield gaps is quite large, and reviewing it is beyond the scope of this presentation. One study that looked at yield gaps for major crops, and world regions recently defined five production constraints and invited a group of experts to assign weights to them to reflect their relative importance (Hengsdijk and Langeveld, 2009). The experts queried were experienced crop specialists from national and international research institutions. Figure II 1-2 shows the study’s estimates of the contribution of the five production constraints to the theoretical maximum yield gap for corn in different parts of the world. It is instructive to see for South Asia, for example, that the estimated yield gap is close to 8 t/ha and is thus very large, because of limited water availability, limited nutrient availability, inadequate protection of the crop from pests and diseases, insufficient or inadequate use of labor or mechanization, and knowledge deficits that result in poor crop management.

The authors acknowledge the difficulty of measuring and comparing yield potentials and actual yield across a range of conditions. Their results are indicative. But the relative contribution of the factors accounted for in Figure II 1-2 is telling, and, for example, the point about knowledge as a constraint on yield makes it quite clear that there is an unmet need for agricultural extension.

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FIGURE II 1-2 Maize yield gap by region and contribution of five production constraints

SOURCE: Hengsdijk and Langeveld, 2009

The task of reducing and closing yield gaps calls for appropriate farm systems management, inputs and technology, services and access to markets. Infrastructure, finance, weather data and risk insurance are among the critical components on the input side, as are functioning markets and distribution systems for seed, fertilizer, tools and appropriate mechanization. Science-based advances and technology are central, including soil testing, improved seed and varieties, seed treatment, new and improved fertilizer technology, micro-irrigation, precision farming and agricultural extension. Mobile phone based applications in

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

agriculture have begun to revolutionize the linkages and transactions between farmers and service providers of many kinds. They are the “up and coming” tool for scaling up extension and linking farmers to input and output markets.

Markets for food and agricultural commodities offer hitherto unseen opportunities for farmers, including small farmers in developing countries and emerging markets. Small farmers no longer want to be seen as subsistence farmers they are, or aspire to become, commercial producers. They are looking for ways to secure access to technology, services, infrastructure such as roads, and markets. Farmers’ organizations are serving an increasingly important role in providing access to these. Although the farmers’ share of the consumers’ dollar at retail tends to be small, organized growers who are working the land with the right kinds of inputs and support and selling into established markets can improve their livelihoods and invest in their future.11 There cannot be sustainability in agriculture without this. However, in many parts of the world, there remain serious barriers to expanding smallholder production: unhelpful governance and institutions, lack of public goods, inadequate services such as credit and extension services for farmers, and land fragmentation.

New paradigms are needed in global agriculture and are emerging: productivity and sustainability are inseparable, markets and consumers are driving change, and agriculture and farming remain important even as economies evolve. Approaches to the food security challenge that focus solely on production are inadequate. Intensification is called for as never before, but it must come about sustainably, heeding on-site and off-site environmental conservation and rehabilitation opportunities and needs; and adapting to, and working to mitigate, climate change. Intensification must take cues from the market and respond to the quantitative and qualitative changes in tastes and demand that are visible wherever one looks, complying with the product and safety standards that modern markets demand. Food safety, standards, and the power of consumers are part of the new reality to contend with—a reality that (together with the liberalization of markets) is shifting agriculture in developing countries and emerging markets from the grains- and staple-based subsistence focus of the past towards high-value, information-intensive, commercial farming. Many smallholders are participating in this trend successfully today; many more should be and—with the right kinds of services and support—can be brought into the process to help fill supply gaps, raise incomes and promote agricultural growth.

Agricultural growth and the adoption of technical progress by farmers are needed even as the sector’s share in countries’ GDP falls. The economic transformation whereby agricultural GDP declines rapidly relative to the total, and agricultural employment declines slowly, is in full swing. Sustainable progress and productivity growth in agriculture are needed for at least six good reasons in this context, all of which relate to and reinforce food security: food availability, conservation of natural resources, diversification of the rural economic space and rural non-farm employment, overall economic growth, poverty reduction, and income convergence between the agricultural and non-agricultural sectors of the economy. To get there, we need enlightened investment in agriculture. Farming first is a good maxim to go by, accepting sustainability and market-driven, science and technology-based modernization as two sides of the same coin.

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11 Reardon and Gulati offer an analysis of how the transformation of supply chains and marketing creates opportunities and challenges when it comes to linking farmers to markets. The organization of farmers becomes essential to lower transactions costs from buyers’ perspective and to raise farmers’ bargaining power. See Reardon, T. and A. Gulati. 2008. The Rise of Supermarkets and their Development Implications. IFPRI Discussion Paper 00752.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

GENERAL DISCUSSION

Participants raised a number of questions regarding productivity increases—what this might mean in terms of prices and ways to stimulate increased productivity. One participant asked whether farmers were likely to increase production to such an extent that food prices would fall. Marco Ferroni indicated that this could happen if productivity rose enough, because farmers are price responsive. He noted, however, that abundant global food supplies and falling prices are unlikely in the foreseeable future because increases in the demand for food are expected to be very large in many developing countries as their incomes grow while production prospects are challenged by natural resource degradation and the threat of climate change.

One speaker emphasized the importance of spillover effects, noting that managing such effects is critical to promoting the use of new agricultural technologies. In fact, he suggested that part of the success of the green revolution was due to the friendship between Norman Borlaug and the Indian minister of agriculture. Other speakers emphasized the importance of continuing support for R&D and mentioned that by reducing U.S. agricultural subsidies by 10 percent and shifting these funds to R&D, U.S. public R&D funding could be doubled. It was also noted that much of the private R&D funding is not directed at food crops but rather at ornamentals— flowers, houseplants and grasses.

Ferroni stressed the importance of political commitment to agriculture, private and public investment in agricultural R&D, and technical support to farmers (for example in the form of agricultural extension) to help raise yields and productivity sustainably. He cited the example of Gujarat, a relatively natural resource poor state, where agricultural production increased up to 10 percent a year because of dedicated government support.

WATER FOR A FOOD-SECURE WORLD12 David Molden, IWMI

David Molden began the session by describing the link between water and food. Estimates place the need for additional food production at about 70 to 100 percent more than we produce now. More food requires more water. Agriculture now takes 70 percent of global water withdrawals. If we continue producing food the way we do now, up to twice as much would go into food production in the form of evapo-transpiration through 2050. Given that we have water scarcity now; that we have reached or surpassed limits already with groundwater decline, shrinking rivers and threatened fisheries; and that climate change brings more risk and uncertainty; we must change the way we think and act about water.

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12 The presentation is available at http://sites.nationalacademies.org/PGA/sustainability/foodsecurity/PGA_062564, presentation by David Molden (May 2, 2011).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

The 2007, the Comprehensive Assessment (CA) defined two types of scarcity, physical and economic (Molden, 2007). Both are related to problems of access. In regions of physical water scarcity, water is fully allocated or over-allocated to cities, agriculture and industry, leaving little or nothing for the environment. In economically water scarce regions, water is available for use, but access is difficult because of limited investment in water infrastructure or limited human capacity to develop and manage water. In both cases, lack of access to water is a threat to future food production, but in very different ways (see Figure II 1-3).

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FIGURE II 1-3 Water Scarcity 2000.

NOTE: 1/3 of the world’s population live in basins that have to deal with water scarcity.

SOURCE: Presentation by David Molden, IWMI, May 2, 2011.

Other limits have already been reached or breached in important food producing regions in ways that compound water scarcity. For example, groundwater levels are declining rapidly in several major breadbasket and rice bowl regions such as the North China Plains, the Indian Punjab, the Ogallala in Western USA (Giordano and Villholth, 2007; Shah, 2007). Rampant land degradation and nutrient depletion limits productivity gains (Bossio and Geheb, 2008). Demand for aquaculture products like fish and shrimp continues to rise (Dugan et al., 2007), which means more demand for freshwater resources to produce these products. Similarly, most of the additional animal-based food products from livestock and poultry will be grain fed, thus requiring more water, as we approach the limits to production on grazing land.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

Climate change will shift patterns of water availability, increase demand from increasing temperatures, and represent a challenge to water managers with increasing variability of rainfall and stream flows.

Economic water scarcity poses a different set of problems with a different set of solutions. In these regions spread across much of Sub-Saharan Africa, South and South-East Asia, and pockets of Latin America, there is limited water access, but high scope to use more water for food production, both directly from rain and irrigation sources. A little additional water for crops at the right time can increase water productivity of water and land. This is most likely to be true in areas of high poverty, so there are poverty and productivity gains to be made (Rockstrom et al., 2007), particularly within rainfed systems (Wani et al., 2009). Hence, it is surprising how little attention is given to water across Sub-Saharan Africa. In semi-arid areas, there is enough seasonal rain available, but short, unpredictable dry spells make farming a risky business. This variability is likely to increase with climate change. The secret to getting through dry spells is adding a little water at the right time. It has been well demonstrated that providing the basics (water, fertilizers, seeds, and good farm practices) can readily lead to double or triple yields where grain yields are one ton per hectare. A reliable water supply reduces risk and encourages investment in the basic inputs.

However, the ways the water is developed and managed will be much different than the designs that served us well for the green revolution. There is a range of options that includes large-scale gravity irrigation, provision of supplemental irrigation, use of groundwater and water harvesting techniques. Increased water storage, utilizing small and large reservoirs, groundwater, wetlands, and soil moisture, is critical to providing water access and is a key climate-change adaptation measure. In fact, the division between rainfed and irrigated agriculture is academic. It would help to think of rain as the ultimate source of water and to consider agricultural water management options that include soil moisture storage, small and large irrigation, and drainage.

A set of new trends will temper water and food actions in the future. First, in some river basins such as the Mekong and the Nile Rivers, there is a marked increase in large dam construction. Related to this is the role of China in development efforts, and in particular water development efforts. Although there are efforts to increase cooperation for transboundary water management, it is not apparent that China is a major player in these discussions. There is a lot of discussion about the sudden growth in land acquisition (“land grabs”) for agriculture. In fact, these are often natural resource grabs as well, as the land is rarely so valuable without the water. Recently, the private sector is becoming increasingly interested in water, recognizing the business risks arising from water scarcity, as well as the opportunities from better water management. Finally there is a silent growth in an informal water sector, especially amongst the poor. People who do not receive water services from formal or government sources figure out how to do it themselves. Much of the groundwater use today is from that informal water economy.

There are only a few basic pathways to grow more food with the Earth’s water: continue to expand rainfed and irrigated land and water use, increase productivity of water resources, encourage trade in food commodities, and modify our food and fiber consumption practices. Large-scale land expansion for agriculture is no longer a viable solution because of ecological limitations. Although there is very limited scope for mobilizing more water in many parts of the physically water scarce world, there is scope for additional water use to intensify agriculture in economically scarce regions, especially in Sub-Saharan Africa, where irrigation is only 5 percent of its potential. Trade has potential to reduce global demand for water for food production if

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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trade is made between areas of high water productivity to areas of low water productivity. However, water is not a key factor in influencing trade policy, and it is also difficult to imagine that poor countries could afford to purchase food to solve a global water problem. There is scope to substantially reduce future water requirements by reducing food waste and by reducing overconsumption of food. Improving water productivity will be the key where water is limited, as it will be for new water developments.

Will there be enough water to grow enough food? The answer is that it is possible to grow the food needed with the water we have, but it is likely that we will do it in ways that cause more degradation and do not address poverty if we stay on the present course. It is also possible that by judiciously applying strategies tailored to local conditions for safeguarding water access, improving productivity of water, through trade, and watching our food consumption patterns, we can limit the amount of additional water needed and can meet poverty and food security goals. These measures are necessary but not sufficient. A focus on improving water management in areas of high poverty will yield the greatest gains in water productivity, where increases in yield also translate to growing more per unit of water. This is in contrast to highly productive areas where yield gains require more water to be transpired. Managing water as an integral part of ecosystems will make our food production systems more resilient and more sustainable. Only if we change the way we think, act and govern water and food will we be able to adequately address the severe water, food, and ecosystem challenges of today and tomorrow.

LAND DEGRADATION AND SUSTAINABLE FOOD PRODUCTION: SUB-SAHARAN AFRICA13

Paul L.G. Vlek, University of Bonn

The state of our lands, both natural and men-appropriated, is difficult to track. That has not stopped numerous agencies from making estimates based largely on expert assessments. The most recent compilation of these assessments was made during the Millennium Ecosystem Assessment (MEA, 2005). It is estimated that around 70 percent of our land has seen degradation in some form or another, whereas 20 percent of the soils are degraded. However, the lack of a sound baseline or any ground truthing and the lack of experts, particularly in Africa, lend limited credence to these estimates.

The state of our forests areas is monitored relatively closely due to the efforts by FAO. Conversion rates are reported by national governments, and the introduction of satellite imagery has allowed verification of these statistics over the past 15-20 years (FAO, 2010). It is clear that deforestation and forest degradation will likely proceed unchecked and with losses at an annual rate of around 16 million hectares of natural forests and tree cover. In the process, livelihoods and ecosystem services that underpin agricultural productivity are lost.

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13 The presentation is available at http://sites.nationalacademies.org/PGA/sustainability/foodsecurity/PGA_062564, presentation by Paul Vlek (May 2, 2011).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

image

FIGURE II 1-4 Change in three classes of land use 1960-2000

SOURCE: Presentation by Paul Vlek, University of Bonn, May 2, 2011.

Deforestation severely disturbs the hydrological cycle and exposes soil to the threat of erosion. It also diminishes the carbon pool and biodiversity, thus contributing to climate change and a loss of services such as pollination. Deforestation is largely due to the pursuit of ecosystem goods through agricultural expansion and overexploitation for timber and fuel. Unsustainable logging removes the most valuable tree species and gives farmers access to complete the conversion process. The real cost of the lost ecosystem services to society is immense and is never reflected in the price of the products. In many cases, the livelihoods of the individual producers taking the land is secured through the mining of the natural resource base.

Tracking the state of our agro-ecosystems is more complex, and data are scarce. Nowadays this problem is partially overcome by the availability of space observation information in the public domain. Global coverage of satellite imagery over a two-decade time slice has spurred new efforts to quantify land degradation. The assumption in this type of analysis is that a declining biomass production can be measured as a decrease in NDVI, a blue/green-spectrum index serving as a proxy for the standing vegetation. If the NDVI monitored from space is showing a decline over the years, the underlying degradation processes on agricultural land must indeed be rather severe. In an analysis of SSA, Vlek et al. (2008) estimated that around 8 percent of the agricultural land and 15 percent of the forest/cropland area exhibited declining NDVIs between 1982 and 2003. Though this may seem modest, once added to the 10 percent that was already claimed to be severely degraded in the late eighties by the expert assessment (GLASOD), the agricultural land resources of Africa are indeed dwindling fast.

However, from a glance at the NDVI map of SSA (Vlek et al., 2008), it is immediately evident that as much land area is degrading as is increasing in NDVI, reflecting biomass accrual. This is particularly evident in regions with little or no human influence and is ascribed to atmospheric fertilization of CO2 and NOx (Vlek et al., 2010). As this phenomenon is ubiquitous, it will have masked land degradation by compensating for degradation processes such as soil erosion or soil mining. Thus, when atmospheric fertilization is taken into account, the agricultural region in SSA impacted by human activity increases from 8 and 15 percent to nearly

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

30 percent for both agricultural and forest/cropland. Additionally, land degradation may be ongoing at micro-scale (patches) that it is not captured as significant in an 8 x 8 km pixel on the satellite image used. As time series of higher-resolution satellites become available, more detailed analysis on a country by country basis should better inform about the state of our land and our soils. In the absence of alternative instruments for monitoring the rate of land degradation in SSA on the ground, satellite-based systems offer the best hope for tracking the state of this vital natural resource on this vast continent. A systematic research effort should be made to verify the accuracy of the findings reported by Vlek et al. and to refine the analytical tool and interpretation of the results. Such an effort certainly would have to include ground truthing and an important assessment on agricultural productivity.

The human impact on the productive capacity of agricultural land in SSA is largely related to unsustainable soil management such as eliminating fallows, removal and burning of crop residues, produce exports and shifts to more demanding crops. The consequences are soil acidification, loss of soil organic matter and nutrients, and soil erosion. Around one million square kilometers (km2) appear affected, 40 percent of which comprises land with inherently good soil and terrain conditions in the most productive areas of Sub-Saharan Africa, threatening food production in the long run. Approximately two-third of this unsustainable land management goes unnoticed as atmospheric fertilization (CO2 and NOx) is making up for some of the depleting processes, so that the actual decline in NDVI signal on agricultural land is noticeable only on 260,000 km2 (Vlek et al., 2008).

Finally, it should be noted that land degradation in Sub-Saharan Africa is happening against a background of increasing population and deteriorating climate conditions in a food-insecure part of the world. It is also the only part of the world where fertilizer use has been stagnant over the past quarter century, stuck at below 10 kg ha-1 yr-1. The persistent decline of biomass productivity induced by mismanagement of agricultural activities against the background of steady growth of Sub-Saharan population (about 2.3 percent annually) is increasing pressure on agricultural land, posing an increasing threat to an already tenuous food security (Vlek et al., 2010).

GLOBAL SEAFOOD—FISHERIES AND AQUACULTURE14

Jason Clay, World Wildlife Fund

Overview

In 2000, seafood represented 0.9 percent of caloric intake. By 2050, the portion of calories from seafood is expected to rise slightly, to 1 percent. By 2010, aquaculture accounted for more human edible seafood (e.g., excluding fish that are used to make fishmeal and fish oil) than did wild caught seafood. Going forward, any increases in global seafood production, at least

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14 The presentation is available at http://sites.nationalacademies.org/PGA/sustainability/foodsecurity/PGA_062564, presentation by Jason Clay (May 2, 2011).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

for the foreseeable future, are expected to come from aquaculture. By 2010, Europe, Asia and North America led the world in total seafood consumption, measured by total weight. However, seafood is also a very important source of protein and calories for many coastal areas in developing countries around the world. In terms of overall trade, seafood production is increasing in developing countries where fisheries have been less depleted, thanks to improved commercial fishing efforts; cheaper labor; and, in the case of aquaculture, temperatures that allow for growing year round. In the case of aquaculture, more than 90 percent of production is in developing countries, though a smaller percentage is actually consumed there.

The Status of Marine Fisheries

Most global fisheries are overexploited or fully exploited. In 1974, 9 percent of global fisheries were overexploited, and 51 percent were fully exploited. By 2006, 25 percent were overexploited, and 52 percent were fully exploited. By contrast, 40 percent of global fisheries were underexploited in 1974 compared to only 23 percent in 2006. Since the early 1990s, total catch of wild caught seafood has been stagnant or even declining slightly. And, total catch levels have been maintained as small, pelagic fish have been caught in increasing numbers to use as ingredients in animal feed, initially in pork and poultry production but increasingly in aquaculture production. Today, more than half of all fishmeal and more than 80 percent of all fish oil are used in aquaculture feed.

The most important species produced globally is the anchoveta, which is used primarily to make fishmeal and fish oil. The Alaska pollock is the most productive of the wild caught fisheries for direct human consumption.

Aquaculture

For the past 30 years, aquaculture production has increased globally at an average rate of 7-10 percent per year. Today more than 400 species are cultured. The most important aquaculture products globally by weight are carps, seaweed, and bi-valves (e.g., oysters, clams, mussels, scallops). The most valuable in terms of international trade are shrimp, salmon, tilapia and pangasius. China is the largest producer of aquaculture products, with nearly 70 percent of the global total. Asia as a whole accounts for nearly 90 percent of all production. While a few species are exceptions, the bulk of aquaculture production is consumed in the country of production.

Aquaculture production is largely a developing country industry with the exception of salmon, some bi-valve species, trout, catfish and striped bass. For the most part, regulatory requirements, zoning issues and the cost of labor push aquaculture production to developing countries.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

Seafood Demand Going Forward

China is the largest player in the global seafood market, with 36 percent of the global market share. Seafood represents 1.5 million jobs and one-third of all animal protein consumed in the country. China produces as much carp as poultry. China is not just the manufacturer for the world; it is also an important food processor. It processes some 50 percent of all white fish globally. Finally, China consumes about one-third of all forage fish and fishmeal and fish oil globally.

Going forward, some animal protein analysts suggest that globally, whitefish from aquaculture (e.g., tilapia, pangasius and catfish) will equal poultry by 2050 and surpass it thereafter. It takes less than half as much feed to produce a kilo of whitefish as a kilo of poultry. The key issues that might affect global aquaculture production are the dependence on pelagic fish as feed sources (by contrast, the three species of whitefish identified above are net fishmeal and fish oil producers, meaning they produce more fishmeal when processed than they consume as a feed ingredient). Other key variables are the availability of water for freshwater species and point source pollution, given that many harvest practices currently involve draining ponds. Still, we don’t, by and large, continue to hunt for red meat. Similarly, going forward, seafood is likely to come increasingly from aquaculture. And Asia will come to dominate not only seafood production but also consumption as their economies strengthen.

The sustainability of seafood is an ongoing concern. The United States has shown that it is possible to bring back many fisheries once they are depleted. It is likely that other countries will attempt to follow the same path. It is difficult to bring back large fisheries that extend across multiple countries. To date, we do not have good examples of major fisheries that have bounced back—at least quickly—from overfishing. Similarly, aquaculture has had significant impacts in the past. To put it in context, aquaculture has been on a very steep learning curve. Agriculture and livestock production have had thousands of years to improve. Global aquaculture, by contrast, has had only a few decades. However, aquaculture has made tremendous strides in reducing the key impacts to more acceptable levels even as production has increased significantly. Waste in aquaculture means not just pollution, but also lost profits, so there are real incentives to improve performance. By contrast, many wild caught fisheries are subsidized and by contrast have fewer direct incentives to improve.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

PRODUCING MORE FOOD AND MORE BIODIVERSITY: IS THERE POTENTIAL FOR BOTH?15

TG Benton, Leeds University

The Food Security Challenge

Global demand for food will grow at a greater rate than the population, and although there are uncertainties, the most widely cited prediction is the FAO estimate that 70 percent more food will be required by 2050 (Bruinsma, 2009). Despite the potential for decreasing post-harvest losses, it is likely that global food production will need to continue increasing at rates similar to those of the last two decades (UK Foresight Programme, 2011). There is some space to expand the global land area under agriculture (Fischer et al., 2002), but this is necessarily limited. First, some of the potential land is forest, and as deforestation is the second major driver of GHG (Smith et al., 2010), using this land in agriculture is counterproductive, as it would increase the rate of climate change. Secondly, productive land is typically the first to be used for agriculture, suggesting diminishing returns if cultivation expands into marginal areas. Thirdly, non-cropped land supplies many other services (from habitation to tourism to carbon storage) (TEEB, 2010), creating strong competition limiting the growth of the global agricultural landbank.

At the same time, as global demand is increasing, there is also growing recognition that agriculture needs to become more environmentally “sustainable” (in the sense that degrading services should not impact on future generations (WCED, 1987)). The value of the ecological services provided in agricultural landscapes is only just beginning to be recognized (Costanza et al., 1997; TEEB, 2010), but there are clear indications that ecology has a direct value in production systems (as well as its cultural values) and may become more important in future agriculture, especially when chemical inputs and mechanization may be restricted by carbon costs.

Benton noted biodiversity conservation can be seen as a positive that will ultimately increase yields rather than the typical “either/or” choice. Natural systems provide a broad range of ecological services, including provisioning services (such as biodiversity producing a range of provisions to fulfill the needs for nutritional security, fiber and fuel), supporting services (such as pollination, natural enemy services, soil fertility, carbon storage, soil protection, flood protection, etc.) and cultural services (creating the market for ecotourism, etc.). The value of the ecological services is gaining recognition (Costanza et al., 1997; TEEB, 2010), with some services assisting a farmer’s yield and others providing more disbursed services of value to society in general. For example, 15-20 percent of total crop production arises from plant species that are wholly or partially animal pollinated (Klein et al., 2007), amounting to a direct contribution of about 10 percent of all food production at an annual value of $153 billion (Gallai et al., 2009). Similarly, “natural enemy” services provided by a range of insects and arachnids, such as small wasps, beetles and spiders, suppress pest outbreaks.

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15 The presentation is available at http://sites.nationalacademies.org/PGA/sustainability/foodsecurity/PGA_062564, presentation by TG Benton (May 2, 2011).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

To explore the tension between production and conservation, it is useful to think of agricultural landscapes as systems that produce two sorts of products: food (and other economic goods like fuel, fiber, etc.) and ecosystem services (which may relate to biodiversity, water, carbon storage or environmental health). In a very simplistic sense, there are two basic land management strategies: land can be (1) farmed extensively over the farmable area, thereby producing less food but more ecosystem services on the same land (“land sharing”), or (2) farmed intensively over a smaller area, and the remaining land can be “saved” to be managed exclusively for ecosystem services (“land sparing”) (Green et al., 2005).

Reaching for Solutions

Value Ecosystem Services (ES) and internalize this value to land managers

The services provided by biodiversity are often underappreciated. Furthermore, provision of services is seen as a common good provided by nature, and therefore external to the system. In production landscapes, recognizing the value of pollination and natural enemy services should help land managers value the management of non-crop areas that act as a reservoir. In the developing world, a variety of community-based approaches are happening to ensure that appropriate action is taken at the community level to preserve the services that aid livelihoods.

Value ES and internalize this value into global markets

Internalizing the values into production costs is also key for many services that have little direct value to landholders. For example, carbon storage (in soils or in non-cropped forests) may be a negative value for landholders, although positive to society at large.

Recognize the range of local-to-distant impacts and value them appropriately

Local actions can have distant impacts, and only through valuing both the near and far impacts will people be able to make informed choices. Again, this requires more sophisticated knowledge and valuation than hitherto. For example, how does environmental protection within the EU trade-off against an increased need to import produce from the developing world?

Incentivize landscape design

Governance is a key to conservation and agro-ecology because ecology is in some sense external to humanity’s typical reasons for owning and governing land. In production landscapes, land managers are often seen as independent actors (both independent of each other and of the landscape context in which they act). There are many “easy gains” to be made from designing appropriate networks of non-cropped land and incentivizing local land managers to work towards realizing them.

Incentivize appropriate consumption patterns

In the developed world (and increasingly in parts of the developing world), the abundance of food at a low relative cost creates an “all you can eat” culture. Reducing demand through encouraging lifestyle change will create many positive effects, from health to environment.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

Changing food culture is a key route towards reducing the pressure on agricultural systems and therefore enhancing conservation (Clay, 2011; Godfray et al., 2010).

Incentivize “sustainable intensification”

It is clear that per-area agricultural productivity needs to be maintained where it is already close to optimal, or increased in the large proportion of the world where it is suboptimal. The challenge is to grow productivity globally whilst protecting the value of the environment. The solution requires (1) thinking at multiple scales, enabling smallholder farmers to raise production whilst minimizing impacts via agro-ecological farming; (2) finding ways of maximizing productivity whilst reducing environmental impacts in production landscapes; and (3) devising ways to value local vs. distant impacts.

SOIL QUALITY OF TROPICAL AFRICA: AN ESSENTIAL ELEMENT OF IMPROVED AGRICULTURAL PRODUCTIVITY16

Uzo Mokwunye, Development Strategy Consultant

The majority of the 800 million people who inhabit Sub-Saharan Africa (SSA) live in rural areas and depend on agriculture for employment and livelihood. But the past three decades have witnessed a stagnant or declining growth in agriculture. Thus, as at 2009, the Food and Agriculture Organization of the United Nations (FAO) recorded that more than 265 million people in Sub-Saharan Africa were hungry and malnourished and that the region remains the only part of the world where the absolute number of the poor and people facing hunger and malnutrition is increasing. To begin to understand why the agriculture sector has underperformed, it is vital to understand the nature of the soil quality of tropical Africa.

Soils of tropical Africa were formed from rocks of Pre-Cambrian origin. These rocks are made up of granites, quartz and quartzite-like materials. Soils formed from these materials are typically sandy. They are dominated by low activity clays that have very limited capacity to hold on to the exchangeable bases such as calcium and magnesium that are required as food by plants. We can therefore say that these soils have inherent low fertility. This situation has not been helped by the high temperatures and heavy rainfalls that are characteristic of the region. The high temperatures and heavy rainfall promote weathering of the rocks and the leaching of the nutrients released during the weathering process to zones where they cannot be utilized by growing plants. Although the high temperatures and heavy rainfalls encourage the growth of vegetation, these same forces promote the rapid decay of dead organic materials. The result is that the soils have very low amounts of organic matter. Soil organic matter is crucial, as it is the main source of nitrogen, a key nutrient for plants. Soil organic matter is also important for maintaining the buffering capacity of the soil. A soil with high buffering capacity reacts more slowly to changes brought about by management practices such as the addition of inorganic fertilizers.

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16 The presentation is available at http://sites.nationalacademies.org/PGA/sustainability/foodsecurity/PGA_062564, presentation by Uzo Mokwunye (May 2, 2011).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

Having been dealt a difficult hand by Mother Nature, how was the tropical African farmer able to grow food for the family? The farmer was keenly aware of the fragile nature of the soils that she/he worked and adopted a system described as “shifting cultivation” for the management. This practice enabled the farmer to cultivate a piece of land for one or two years. The piece of land was then left to fallow for upwards of fifteen to twenty years to regenerate its fertility. This practice worked as long as the population was small. With increased and increasing population, farmers have been forced to stay on the same piece of land. This intensive cultivation has resulted in massive losses of plant nutrients, a process now described as “nutrient mining.” It has been determined that by 2002, 132 million tons of nitrogen, 15 million tons of phosphorus and 90 million tons of potassium had been lost from 37 tropical African soils in 30 years.

The most efficient way to improve the soil fertility is through the use of fertilizers, primarily inorganic fertilizers. However, data from the International Fertilizer Industry Association (IFA) shows that tropical Africa is not a significant producer of inorganic fertilizers. Therefore, if agricultural production must be boosted through the use of inorganic fertilizers, such products must be imported. However, because many countries in tropical Africa have no access to ports and because of poor transportation infrastructure, fertilizer prices are very high. For example, 1 metric tonne of urea costing USD 90 in Europe would cost USD 400 in Mombasa or Beira on the East African coast, USD 500 in Western Kenya and USD 700 in Lilongwe (Malawi). At these prices, most smallholder farmers cannot afford to buy the fertilizers needed to improve the fertility of the soils (see Figure II 1-5).

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FIGURE II 1-5

SOURCE: Presentation by Uzo Mokwunye, May 2, 2011

At the beginning of the new Century, African Heads of States and Governments adopted the Comprehensive Africa Agricultural Development Programme (CAADP)17 as the framework for the development of the overall economy of Africa. The African leaders committed themselves to allocate a minimum of 10 percent of national budget to development in four priority areas known as Pillars. Pillar 2 expressly addressees the improvement of rural

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17 This program is carried out under the New Partnership for Africa’s Development (NEPAD). See http://www.nepad-caadp.net (accessed on October 6, 2011).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

infrastructure and trade-related capacities for access to markets. In 2006, the heads of state and governments met at Abuja at the Africa Fertilizer Summit and declared fertilizer as a “strategic commodity without borders.” Africa’s political leadership is thus well aware of the importance of providing adequate support to agriculture. Africa’s friends and development partners must hasten to the aid of the governments as they struggle to implement CAADP.

GENERAL DISCUSSION

Several participants raised questions about the link between conservation of biodiversity and agriculture. Laurian Unnevehr began the discussion by talking about a potential conflict in the Salinas Valley with pressure to clear away grasses and other vegetation from fields and water conveyances as a way of assuring the safety of livestock products. Tim Benton suggested that the need to make such tradeoffs is relatively common. He noted that if the ecosystem services being provided by these resources is limited, then the benefits of increased food safety could easily outweigh the biodiversity benefits. The need to value ecosystem services and balance these services against other factors was prominent in the discussion with Benton, emphasizing the need to educate farmers, especially in developing countries, about the values obtained from biodiversity such as pollination, flood protection, and soil fertility, as well as fuel and fiber.

Other participants raised questions about organic farming and whether or not organic farming was likely to be a major contributor to meeting world food needs. Most participants suggested that organic farming was a useful model of good farming practices that could be more widely adopted but that its contribution to providing needed increases in food crops was very limited. One participant in fact noted that if the United States and the EU moved to exclusively organic system farming, more than twice the amount of land currently under cultivation would be required, with its attendant environmental costs.

A number of participants talked about the role and importance of international trade in agricultural commodities as a way to meet the needs of food-deficit countries. Though many stated that this was important, others emphasized that poor people can not afford imported food and also that in many countries expanding agricultural production is a key ingredient for long term economic growth.

FOOD SECURITY, FARMING AND CLIMATE CHANGE TO 2050 SCENARIOS: RESULTS AND POLICY OPTIONS18

Gerald C. (Jerry) Nelson, IFPRI

Jerry Nelson set the stage for his presentation on climate change and food security by reminding participants that today’s food security challenges are unprecedented. World population is expected to increase by 50 percent between 2000 and 2050, with almost all of the increase in developing countries. At the same time, income growth in developing countries will

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18 The presentation is available at http://sites.nationalacademies.org/PGA/sustainability/foodsecurity/PGA_062564, presentation by Jerry Nelson (May 2, 2011).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

increase demand for high value foods such as meat, fish, fruits, and vegetables. And climate change will be a “threat multiplier,” affecting cropping systems worldwide.

Nelson’s presentation focused on three major themes: the current state of knowledge about climate change; the impact of climate change on crop yields, supply, demand and trade; and the assessment of the challenge of long term food security with and without climate change.

Basing his discussion on direct climate change effects on a suite of four possible climate futures, Nelson stated that average temperatures would likely increase substantially—especially after 2050—and that major changes in precipitation patterns are possible. He also said that there will be increased variability in temperature and precipitation patterns. He pointed out that there are big differences among model outcomes in terms of the location and magnitude of these changes. Nelson noted that the combined effects of higher temperatures and more varied precipitation were likely to have widespread negative consequences for agricultural yields. Average increases in temperature alone would have some impact on productivity, but if temperatures spike during critical growth periods, crop yields would be much more seriously affected than average temperature increases would suggest.

Important outputs of the scenarios are estimates of future changes in precipitation. Interestingly, the two models, one from the Australian Commonwealth Scientific and Industrial Research Organization (CSIRO) and the other from the University of Tokyo’s Center for Climate System Research (MIROC), yield very different outcomes. The CSIRO model has smaller and more evenly distributed increases in precipitation, whereas the MIROC model has larger average increases with decreased rainfall predicted in important world agricultural regions. See slides below (Figures II 1-6; 1-7):

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FIGURE II 1-6 Change in average annual precipitation, 2000-2050 CSIRO GCM, A1B (mm)

SOURCE: Presentation by Jerry Nelson, IFPRI, May 2, 2011.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

image

FIGURE II 1-7 Change in average annual precipitation, 2000-2050 MIROC GCM, A1B (mm)

SOURCE: Presentation by Jerry Nelson, IFPRI, May 2, 2011.

See the slide below (Figure II 1-8), which displays changes in maize yields with the MIROC model outputs.

image

FIGURE II 1-8 Yield Effects, Irrigated Rice, MIROC A1B (percent change between 2000 and 2050 climate)

SOURCE: Presentation by Jerry Nelson, IFPRI, May 2, 2011.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

Nelson described a set of plausible scenarios developed by IFPRI based on three overall income/population scenarios and five climate scenarios for a total of 15 plausible futures. World prices are an important indicator of the combined effects of income, population and climate. The slide below shows both the mean price increases with and without climate change as well as the range of increases that arise with different climate scenarios, holding income and population growth patterns constant.

image

FIGURE 1-9 Climate Change Scenario Effects Differ (The vertical axis represents price increase [percent], 2010-2050, baseline economy and demography)

SOURCE: Presentation by Jerry Nelson, IFPRI, May 2, 2011.

In order to increase food security and resilience to climate change, Nelson suggested that three specific objectives must be met: broad based economic growth, investments targeted to increase agricultural productivity, and strengthened international trade agreements. He emphasized the need to raise poor people’s incomes to achieve food security and increase climate change resilience. The scenarios described above suggest that the benefits of broad-based economic growth are greatest in middle income countries where there could be as much as a 50 percent decline in the number of malnourished children under an optimistic scenario. A pessimistic scenario results in a decline in the number of malnourished children of only about 10 percent on average, with a 20 percent increase in low-income developing countries.

Nelson said that although it is still possible to expand the amount of land under cultivation, most productivity increases are likely to result from increasing investment in existing agricultural lands. Such investments should focus on expanding irrigation and improved irrigation efficiency, biological research, and the expansion of rural roads.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

He concluded that future climate variability will likely stimulate expanded trade flows from countries experiencing expanded agricultural production levels to those with contracting levels of production. Trade should help reduce some of the human suffering likely to occur from food shortages.

RISKS AND VULNERABILITIES FROM CLIMATE CHANGE19 David Lobell, Stanford University

This presentation focused on the risks that climate change poses to global food production. David Lobell noted that the emphasis on global scale should not detract from the fact that different regions could be affected differently, or that different uncertainties may be more relevant at some scales than at others. Below is a brief summary of the main points of the presentation.

Climate change represents a significant challenge to maintaining productivity growth rates in global agriculture.

Early work on this topic suggested that the benefits of higher CO2 should more than compensate for any climate-related losses in global productivity until 2-3°C of global mean temperature increase. These assessments predicted that climate change would hurt developing countries before that time, but that gains in higher latitudes would buffer the global impacts. More recent work has painted a slightly more challenging picture, for two main reasons. First is that the harmful effects of warming appear stronger than initially thought, in particular for the effects of extreme heat on crop production. Early model results often suggested that adopting longer maturing varieties or earlier plantings would be an effective adaptation, but the fact that extreme heat is damaging and not included in most models challenges this view. In particular, there is little evidence for greater tolerance of extreme heat for corn grown in hot vs. cool locations.

Second is that the beneficial effects of CO2 as measured in chamber or greenhouse experiments seem to be higher than what has been observed in field experiments. This appears to reflect the fact that moisture conditions in enclosed experiments were generally lower, which led to strong effects on water use efficiency, which were misinterpreted as photosynthesis effects. Although some modelers have claimed that the values used in past model assessments agree with field experiment results, it appears that the modeled responses that include water use efficiency effects are indeed much stronger than observed.

In addition to CO2 and temperature, changes in drought frequency are likely throughout much of the tropics and subtropics, and increases in pest and disease pressures will likely be more severe in several regions. Moreover, floods are increasingly common and will likely

____________

19 The presentation is available at http://sites.nationalacademies.org/PGA/sustainability/foodsecurity/PGA_062564, presentation by David Lobell (May 2011).

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

continue to be so, and ozone damage (which is in part facilitated by higher temperatures) is substantial. The effects of all of these changes are still poorly quantified at the global scale, but in sum they are likely to represent a significant challenge to maintaining productivity growth.

Adapting to climate change is likely to be one of the handful of key factors going forward (along with increasing input use and efficiency, maintaining rust and disease resistance…).

Given the above considerations, our ability to adapt to climate change is one of the major uncertainties in future food supply. It is equally or more important to increase input use in Africa, to increase the efficiency of input use globally, and to improve resistance to major rusts and diseases. All of these, including climate adaptation, are of course linked to an underlying challenge—the declining investments in agriculture and the long time lags in the system (as emphasized by Pardey’s talk20).

The clearest risk (estimation) is from extreme heat, the main opportunity is higher CO2.

Despite much attention and concern about changes in precipitation, and the significant role that rainfall changes might play at regional scales, the global challenges result mainly from increased temperatures. Note that this does not diminish the importance of drought tolerance, because trends in drought are often driven by greater evaporation rates associated with warming. Targeting crop development to higher CO2 environments represents an untapped strategy that could more fully exploit the benefits of higher CO2.

The clearest problem crops are wheat and maize (assuming that rice continues to have water, and that roots/tubers benefit a lot from CO2).

Although maize is typically thought of as a heat tolerant crop, it is already grown in some of the harshest environments where further warming will be detrimental. Wheat is a cool season crop, which is hurt in most places from warming. A possible exception is where warming allows one to switch from spring to winter wheat varieties. Rice appears less sensitive, although it is still affected. In particular, rice is damaged from high day temperatures during flowering, which can cause spikelet sterility. Tuber crops appear in experiments to benefit the most from higher CO2, although their sensitivity to temperature and moisture changes are less well known.

____________

20 See Agricultural Productivity and Natural Resource Endowments by Philip Pardey.

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

The public sector can play an important role in adapting, particularly in regard to genetic conservation, heat stress and CO2 responsiveness.

The private sector will obviously play an important role in innovation, in particular for developed countries and for crop traits that are already considered important for yields (such as drought, which is increasingly the target of seed companies). But for crops without a large private sector, and for traits without much interest in current climate, there is a need for sustained public investment. This is especially true given the lags in return on research investments, which means that crops being developed today will likely reach farmers in a significantly warmer world, and one with higher CO2.

There are very likely already sizable losses being incurred from climate change, which at a time of biofuel mandates and high prices, translates to ~$50 billion per year.

The results of a recent analysis were presented, which examined effects of changes to date. Although climate change is often thought of as a risk to future production, many regions have already experienced significant shifts. The analysis revealed a few important points: (i) The warming rates are such that net negative impacts at the global scale are apparent. (ii) Even with positive effects of higher CO2, the sum of climate and CO2 trends has been negative. This is not exactly analogous to the studies mentioned in the first point above, because we examined actual climate trends, not the component of climate trends forced by higher greenhouse gas concentrations. (iii) There are important differences between crops, with maize and wheat showing losses (see the fourth point above), but rice and soybean less so; (iv) There are important regional differences, with North America less affected than other regions. Whether or not these same regional differences persist will depend on better understanding the causes of recent regional climate trends. Overall, the impact of warming could be affecting productivity enough to alter conclusions from analysis of trends in multi-factor productivity discussed by Pardey and others, and also represents a likely minor but non-trivial cause of the increase in food prices over the past decade. The results suggest that the added stress from warming since 1980 leads to roughly $200 billion in lost productivity, representing a big payoff for effective adaptation. Gains from higher CO2 likely offset about three-fourths of this loss. Although $50 billion per year can be viewed as a small fraction of overall agricultural value, the impacts are likely to grow with time, as illustrated in the previous talk. Lobell stated that the fact that we already see sizable effects means that adaptation efforts are useful not only for the future, but also for today.

GENERAL DISCUSSION

The discussion following the climate change presentations focused largely on the models used in the analysis—the elements included in the models and the extent to which potential impacts were not assessed. One speaker noted that an important effect of climate change is dramatic changes in the length and timing of the growing season. He noted that these changes

Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
×

may require farmers to shift from traditional crops to other crops that are easily adapted to changes in the growing season as well as changes in the length of the rainy season. Other speakers noted that the IFPRI model assumes that the supply of land is very inelastic—that large price changes in crop prices will not cause much change in net agricultural land. Other models discussed by Gerry Nelson assume the land supply is more elastic, and this is a major reason for differences in results from various models of long run changes in global agricultural output growth.

Several questions were raised about the potential impacts on agriculture of increased CO2 levels. David Lobell said that these increases could decrease the amount of water consumed in forested areas, making more runoff available for agricultural crops. But he noted that higher projected temperatures and evaporation rates could reduce this effect. In addition, he noted that increased CO2 helps most when crops have sufficient nitrogen. But in many cases, African soils have limited nitrogen, and the costs of nitrogen based fertilizers are high, so the increased CO2 is not likely to spur productivity increases in Africa. Another issue not generally included in the climate models is the potential increase in ozone levels, which tend to decrease agricultural yields.

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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Suggested Citation:"[Part II]: 1 ACHIEVING SUSTAINABLE FOOD SECURITY: CHALLENGES AND OPPORTUNITIES." National Research Council. 2012. A Sustainability Challenge: Food Security for All: Report of Two Workshops. Washington, DC: The National Academies Press. doi: 10.17226/13378.
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Next: [Part II]: 2 APPROACHES TO ACHIEVING SUSTAINABLE FOOD SECURITY »
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The National Research Council's Science and Technology for Sustainability Program hosted two workshops in 2011 addressing the sustainability challenges associated with food security for all. The first workshop, Measuring Food Insecurity and Assessing the Sustainability of Global Food Systems, explored the availability and quality of commonly used indicators for food security and malnutrition; poverty; and natural resources and agricultural productivity. It was organized around the three broad dimensions of sustainable food security: (1) availability, (2) access, and (3) utilization. The workshop reviewed the existing data to encourage action and identify knowledge gaps. The second workshop, Exploring Sustainable Solutions for Increasing Global Food Supplies, focused specifically on assuring the availability of adequate food supplies. How can food production be increased to meet the needs of a population expected to reach over 9 billion by 2050? Workshop objectives included identifying the major challenges and opportunities associated with achieving sustainable food security and identifying needed policy, science, and governance interventions. Workshop participants discussed long term natural resource constraints, specifically water, land and forests, soils, biodiversity and fisheries. They also examined the role of knowledge, technology, modern production practices, and infrastructure in supporting expanded agricultural production and the significant risks to future productivity posed by climate change. This is a report of two workshops.

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