By Robert L. Thompson – Gardner Endowed Chair in Agricultural Policy Emeritus, University of Illinois in Urbana-Champaign, USA; member, Nestlé CSV Advisory Board
Global challenges and opportunities
The world demand for food is expected to double in the first half of the 21st century – with half of that growth coming from population growth (from 6 billion to 9 billion people) and half from growth in purchasing power of low-income consumers.1 The world population is projected to grow between now and 2050 by 2.6 billion people. The current population of China is 1.3 billion, so the world’s farmers are being asked to increase their production over the next 40 years by enough to feed two more “Chinas”.
Table 1: Projected population growth (in millions)
|East & Southeast Asia
|South Central Asia
|North Africa & West Asia
Source: Population Reference Bureau. 2010 World Population Data Sheet.
About 40% of the world’s population – 2.6 billion people – live on less than USD 2.00 per day, with 1.4 billion of them living on less than USD 1.25 per day2. About 925 million people lack sufficient purchasing power to access even enough calories to sustain a medium level of physical activity. Most hunger in the world is associated with lack of purchasing power. The rich in no country go hungry except in times of war, natural disaster or politically imposed famine.
Table 2: Incidence of extreme poverty, 2005
||Less than USD 1.25/day (%)
||Less than USD 2.00/day (%)
|East Asia and Pacific
|Eastern Europe & Central Asia
|Latin America & Caribbean
|Middle East & North Africa
Source: World Bank
ROBERT L. THOMPSON: Gardner Endowed Chair in Agricultural Policy Emeritus, University of Illinois at Urbana-Champaign, USA; member, Nestlé CSV Advisory Board
Those on very low incomes spend a large percentage of their meagre incomes on food.3 When their incomes start to rise, they spend most of the first increments on food – first to access enough calories to overcome hunger and then to upgrade the quality of their diets, including more fruit, vegetables, animal protein and edible oils. Successful poverty reduction has the double effect of achieving the humanitarian goal of reducing hunger but, at the same time, unleashing a disproportionately large increase in consumption of agricultural products.
Urbanisation also leads to changes in people’s diets, which add to per capita consumption of agricultural products. In 2009, for the first time in the history of humanity, more than half of the world’s population lived in cities. The share of the population living in cities is projected to reach 60% by 2030 and 70% by 2050.
The combined effects of population growth, broad-based poverty reduction and urbanisation are likely to cause global demand for food to double in the first half of this century. Will the world’s farmers be able to double production to feed the world’s larger population better than today at reasonable cost without damaging the environment?
Increasing agricultural production
There are only two ways to expand agricultural production: increase the area planted or increase the production per unit of land, which may, where the climate permits, entail growing more than one crop on the same land each year. Farmers could double the number of hectares of land in production; however, there is only about 10% more potentially arable land that is not forested, highly erodible or subject to desertification.4 Expansion beyond this would involve massive destruction of forests and, with them, wildlife habitat, biodiversity and carbon sequestration capacity, which would accelerate global warming. Most of the potentially arable land is inferior to that already in production and is located in remote areas of sub-Saharan Africa and South America where infrastructure is minimal. To sustainably double agricultural production will require that most of the expansion come from increasing the production per unit of land already in use.
The availability of fresh water to agriculture may be an even greater constraint to doubling production than the availability of land. Farmers use about 70% of the world’s fresh water. With more than half of the world’s population now living in cities, there is no way the world’s farmers will have access to 70% of the fresh water. Cities will outbid farmers for available water. Whereas farmers may have to double the average productivity of the land already in agricultural production, they may have to triple the “crop per drop”, the output per unit of fresh water they use.5
Figure 1. Distribution of world population and arable land
East and South Asia have more than twice as much of the world’s population than their proportion of arable land, and while the Middle East and North Africa has similar proportions, it lacks water for agricultural production. The population and income of these three regions are projected to grow significantly, placing greater demands on the world food system. Sub-Saharan Africa, with the fastest growing population, has similar proportions of arable land and population, and its relative abundance of land is one reason the land-scarce countries of Asia and water-scarce countries of the Middle East are interested in acquiring land there.
Source: World Bank. World Development Indicators.
Map 1. Croplands of the Earth
Most of the world’s principal crop production regions (darker shading) lie in the northern hemisphere. South Asia, with the largest total population and the largest number of extremely low-income people, has some of the darkest shading, as do the densely populated regions of East and South-East Asia. In these regions, as well as in North America and Eastern Europe – two of the world’s great grain baskets – most of the arable land is already in crop production. South America and Sub-Saharan Africa have most of the additional land that could be brought into production.
Source: SAGE, University of Wisconsin, Madison, Wisconsin, USA.
Map 2. Climatic constraints on land in crop production
Low temperatures and insufficient moisture constrain the land in crop production. Long-term climate change projections suggest that the average temperature will increase more in the high latitudes of the Northern Hemisphere than at the Equator. This should shift the margin of crop production further north into Canada, Russia and Alaska, expanding the area of potentially arable land in those countries. Long-term changes in the volume and timing of precipitation will also affect the extent and location of arable land in the future; however, the various climate projection models differ more on future trends in precipitation than in temperature.
Source: International Institute for Applied Systems Analysis, Laxenburg, Austria.
Map 3. Inherent land quality in regions without severe climate constraints
The inherent quality of the soil in regions without severe climatic constraints is categorised into performance (fertility) and resilience (resistance to erosion). The green areas – representing the soils with the highest performance and resilience – are seen in the Midwest of the United States, the Pampa of Argentina and the region north of the Black Sea. In the savannah region of Brazil (cerrado), where cropland was recently expanded, the soils have low–medium performance and medium–high resilience. They can be made very productive with purchased inputs, but have a higher unit cost of production. Most of the 10–12% “potentially arable” land is found in South America and sub-Saharan Africa.
Source: Natural Resources Conservation Service, U.S. Department of Agriculture, Washington, DC, USA.
Variations in crop yield
There are great differences among regions of the world in crop yields (agricultural production per unit of land) with the highest cereal grain yields in Western Europe, East Asia and the Midwest of the United States; yields of about the world average in South America, Central Europe, Southeast Asia and Australia; and low yields in sub-Saharan Africa, South and Central Asia, north-eastern Brazil and Central America. The wide differences in yield suggest that it should be possible to significantly increase productivity per unit of land. With their low yields, many low-income countries’ farm sectors are contributing less to their national food supply and global food security than they could.
Map 4. Cereal grain production per hectare
Illustrating the differences in the average yield of cereal grain production (in tonnes per hectare) across the world, regions range from very low per-hectare yields (dark blue) to the highest (dark red). The global average yields of the three main cereal grains – wheat, maize and rice – are 3.0, 5.0 and 4.25 tonnes per hectare, respectively, all of which fall in the green range of the colour spectrum. The yellow "mid-range" of the spectrum is approximately double the world average yields of principal cereal grains.
Source: SAGE, University of Wisconsin, Madison, Wisconsin, USA.
The large differences among regions in grain yields reflect differences in genetic potential embodied in the seeds planted; availability of water in the root zone of the plants from precipitation or irrigation; the adequacy of the nutrition available to the plants from the soil or fertilizer (organic or inorganic); and the effectiveness of control of weeds, insects, birds and disease that reduce productivity.
It is, of course, the farmer who orchestrates this whole process – after choosing what varieties of what crops to grow, attempting to achieve as much of the genetic potential embodied in the seeds as possible under the unpredictable weather conditions and pest infestations of each growing season. Farming is an inherently risky business with volatile agricultural commodity prices and crop yields. Farm revenue is the product of two random variables not under the farmers’ control: price multiplied by yield.
Low household incomes
Most of the world’s agricultural production is conducted on family farms on which members of the farm household provide most of the labour. In addition to providing part of the family’s annual food supply, farming provides the household cash income – receipts from selling its products less what it has to pay for production inputs and hired labour.
Most of the world’s farm households earn significantly less than households whose income comes from other economic activities. According to the World Bank, 75% of the extreme poverty and associated hunger in the world is in rural areas, and according to the UN Special Rapporteur on the Right to Food, 80% of the world’s hungry are involved in food production. Low income is only one aspect of poverty. The World Bank’s Voices of the Poor characterises poverty as “deprivation in well-being... To be poor is to be hungry, to lack shelter and clothing, to be sick and not cared for, to be illiterate and not schooled... Poor people are particularly vulnerable to adverse events outside their control.” The majority live in remote rural areas, far from roads, markets, schools and health services.
The comments on this page are the author’s independent opinions and are not necessarily shared by Nestlé.
1. Already a decade into the 21st century, global food demand is projected to grow 70-80% by 2050. When the growing demand for agricultural commodities as industrial raw materials (including biofuels) is added to this, the world’s farmers will likely need to double agricultural production in the next 40 years.
2. Per capita incomes of USD 1.25 and USD 2.00 are in purchasing-power adjusted dollars. They are corrected for differences in the cost of living in different countries, the largest component of which is food in the case of the poor.
3. The food consumed by those on low incomes tends to be mostly raw agricultural products with little value added between the farm where it was produced and the consumer. After one’s income reaches a certain level, further increments to income add little to demand for raw agricultural products. After that point, what is spent on food from increments to income is spent on value-added after the raw product leaves the farm, eg convenience, packaging, processing and eating out in restaurants.
4. There are vast grasslands in regions of the world which are too dry for annual crop production, but which make a significant contribution to the world food supply in the form of meat and milk from ruminant livestock (cattle, goats and sheep).
5. Most of the world’s farmers pay nothing for the water they use, so they have little incentive to adopt water-saving technologies. It is politically difficult to start charging a positive price for water in a country where farmers have never had to pay anything for water, however this may become necessary in the future to achieve a tripling in the agricultural output per unit of water used.