Global issues
The food price spike of 2008 was a warning of what is to come
A convergence of factors has made food security one of the most important global issues. An increasing population wants a more varied diet, but is trying to grow more food on less land with limited access to water, all the time facing increased costs for fertiliser, and fuel for storage and transport.
Video: Dr Giles Oldroyd describes global food issues
Duration: 0:00:55 - Video transcript
The world’s population is predicted to hit 9Bn by 2050, up from today’s total of nearly 6.8Bn, and with it food demand is predicted to increase substantially (ref 1).
The food price spike of 2008 was a warning of what is to come. Staple food prices rocketed – wheat up 130%; sorghum rose by 87% and rice 74% – and caused riots in 36 countries. The government of Haiti was toppled as people took to the streets (ref 2).
2008 saw civil unrest due to the price of food and fertiliser. Image: SFTHQ
2008 saw an extra $1.2Bn (£613M) in food aid pledged to help 75M people in 60 nations. But UN Secretary General Ban Ki-moon warned up to $20Bn (£10.2Bn) a year was needed to alleviate the crisis.
More people die each year from hunger and malnutrition than from AIDS, tuberculosis and malaria combined (ref 3), and the World Bank estimates that cereal production needs to increase by 50% and meat production by 85% between 2000 and 2030 to meet demand (ref 1).
In early 2009, food crises persisted in 32 countries (ref 6) from the 36 affected in 2008. And all at a time when global food reserves are at their lowest levels for 30 years (ref 4).
Put simply, the world needs to grow more food now.
Problems
There are many factors that affect food production. The post-war ‘second agricultural revolution’ in developed countries, and the ‘green revolution’ in developing nations in the mid-1960s transformed agricultural practices and raised crop yields dramatically, but the effect is levelling off and will not meet projected demand (ref 5).
Per capita increases in food production have stalled (click for enlarged image)
At the same time, many other factors are having severe impacts on food production: water stress and desertification is reducing the amount of arable land; many pests are becoming resistant to insecticides, but many of the most effective chemical agents are now banned under environmental regulations; underdeveloped infrastructure means that losses increase further during transport and storage; consumption patterns are changing and developing nations such as India and China have an increased appetite for meat, and climate change is bringing new microbial diseases to food-growing regions along with more extreme and unpredictable weather patterns.
Pestilence
Estimates vary, but around 25% of crops can be lost to pests and diseases, such as insects, fungi and other plant pathogens (ref 6).
New pest outbreaks can, and do, appear – they are not the stuff of Biblical legends – but the results are as devastating. In early 2009, a state of emergency was declared in Liberia after it was invaded by a new species of caterpillar. When the problem spread to neighbouring Guinea it sparked fears of a regional food crisis (ref 7).
The pest was at first misidentified as the African armyworm, Spodoptera exempta, which are ravenous feeders of the early stages of cereal crops such as corn, rice, wheat, millet and sorghum, as well as pasture grasses. Like Desert Locusts, the moth larvae change form when they aggregate to form a gregarious ‘marching army’ phase (hence the name).
African Armyworm outbreaks can devastate crops. Image: University of Lancaster
Armyworms are a serious pest in Kenya, Tanzania and surrounding countries in most years. In particularly bad years, such as 2005, larval densities exceeded 1000 per square metre and crops were destroyed in a matter of hours.
The caterpillars in Liberia struck 65 towns, and the Ministry of Agriculture reported that up to 20,000 people left their homes, the fields empty and markets devoid of food that had more than doubled cost in surrounding areas. The pest was later identified as Achaea catocaloides, another moth which occurs throughout West Africa and typically feed on the Dahoma tree but can develop in large numbers and attack agricultural crops (ref 8).
Then there are firmly established pests like the African Witchweed menace, also known as Striga. The weed produces more than 50,000 seeds which lie viable in the soil for up to 20 years, competing with crops for nutrients when they germinate. In Africa, 100M hectares of land are infested with Striga seed and yield losses of 40-100% are common. Striga causes annual losses in excess of $7Bn and adversely affects food security for more than 100M people; in fact there is a near perfect overlap between areas of Striga infestation and subsistence agriculture where hunger prevails (ref 9).
Around the world and particularly in Asia, ‘rust’ fungal diseases of rice and wheat are constant threats. In 1999, a strain of wheat rust emerged in Uganda which is resistant to the three genes that confer rust resistance in the majority of the world’s wheat crops (ref 10). The strain first spread to Ethiopia, Kenya and Somalia, and then across the Red Sea into Yemen and Iran. If it spreads further into Pakistan, a major cereal producing nation, a global food crisis could result (ref 11).
Video: Professor John Lucas, Rothamsted Research, describes wheat rust
Duration: 0:00:24 - Video transcript
Waste
Pests may consume large quantities of crops once they are grown, or prevent them growing at all, but in the developing world up to 37% of food harvested can be lost before it is consumed owing to insufficient processing, storage and transport. Estimates vary, but figures for rice losses include 5-23% in China and 10-25% in Vietnam (ref 12).
Every day 4.4M apples, 5.1M potatoes, 2.8M tomatoes and 1.6M bananas are binned
Even after food is grown, stored and transported, serious losses can occur, and in developing nations where ‘plentiful’ food is wasted. A review of food waste in the US calculated that 43Bn kg of food, just over a quarter of the amount available to consume, was lost from retailing onwards (ref 12).
And when 20% of food is lost it’s not just the food that is wasted – it’s 20% of the land, water, labour, seed, pesticide and fertiliser – so a financial and environmental loss too.
Similar losses are echoed in the UK. Every day 4.4M apples, 5.1M potatoes, 2.8M tomatoes and 1.6M bananas are binned (ref 13). 2009 figures from WRAP, government's anti-waste arm, reveals that including liquid food the UK throws away 8.3M tonnes every year: £12Bn, or around £680 for the average family (ref 14).
Water
Farming accounts for 70% of the world’s use of fresh water that is globally extracted for human use (ref 15) and the UN predicts that irrigation demands will increase by 50-100% by 2025. 2.8Bn people currently live in areas of water stress, a figure predicted to rise to 3.9Bn by 2030 (ref 16).
More than 30 countries have been involved in ‘water wars’ and 145 countries share lakes and river basins, the use of which is governed by more than 300 cooperative agreements between nations. In Africa, a quarter of the population already lives with chronic water stress and water is increasingly being seen as a source of potential conflict between nations eager to secure their future harvests (ref 16).
It’s no surprise then, that access to water is becoming a major issue when on a global scale, the amount of fresh water available per person is falling rapidly (ref 17).
Countries are keen to divert water to irrigate land on large scales, for example by building large hydroelectric dams and mega-canal projects, because relying on rainfall can adversely affect an entire continent. In South America, the 2008 wheat production was halved by drought in Argentina, and persistent dry weather is adversely affecting prospects for the 2009 coarse grains in the sub-region.
Irrigation has drained the Aral Sea. Image: NordNordWest (click for enlarged image)
Areas of potential tension include the Mekong Delta (China plans 8 dams that will divert water from Myanmar, Thailand, Laos, Cambodia and Vietnam); between Bangladesh and India (54 rivers flow between the countries, but India had plans to divert water from the Ganges to its water-poor south); and in the Middle East, Turkey and Syria have both dammed the Euphrates, which puts water stress on downstream Iraq. Furthermore, the River Jordan, which supplies water to Israel, Syria, Jordan and the Palestinian territories, could shrink by up to 80% by the end of the century, sparking tensions in an already volatile region.
Climate change
Climate change associated with agriculture is also a global issue. Agriculture is a significant contributor to greenhouse gases and is estimated to account for 10-12% of total greenhouse gas (GHG) emissions (ref 1). Some estimates are much higher when land-use changes, such as deforestation for farming, are taken into account – up to 30% of 2004 human-induced GHG can be from agriculture and land use (ref 18).
Climate change is predicted to increase desertification.
Image: Tomas Castelazo
It should be noted that climate change will benefit agriculture is some ways: extra CO2 in the atmosphere will lead to plants fixing more carbon, and global warming will also lead to huge swathes of land, particularly in Siberia and Canada, becoming suitable for industrial-scale farming.
However, a warming world will increase the amount of desert in the world, increase localised drought in areas such as North America, Africa and Australia, and may exacerbate problems such as flooding in Indonesia and South America. The increased temperature will also increase activity in insects – the principal pests of food – which may mitigate any yield benefits.
Climate change will be good and bad for food production, but it’s the pace of change that makes it a problem. If the world can’t establish new agricultural zones as fast as others are lost – as is predicted – the net result will be negative.
Sustainability
Food production produces significant quantities of GHGs, and there are concerns that meeting the food security challenge must be achieved sustainably.
More food is being grown now than in any other time in human history (ref 6). The FAO estimated in 2007 that crops would be 4.9% higher in 2008 at a record 2,232M tonnes and 2008 was indeed a record for crop production.
But critics of the modern agricultural practices argue that the improvements are not sustainable because the increased yields are tied to intensive application of oil-based fertilisers the cost of which is closely tied to the price of oil (and natural gas) which also peaked in 2008. The application of agrochemicals and irrigation systems also require large inputs of energy.
Total fertiliser use has risen five-fold since 1960 (click for enlarged image)
Putting aside the issues of soil erosion, loss of fertility and reduced biodiversity associated with modern farming, they say the real problem is that meeting the food security agenda using current techniques cannot be achieved without serious degradation to the environment and will act as a catalyst to human-induced climate change.
As National Farmer’s Union (NFU) President Peter Kendall remarked at their 2009 conference: “We are in an era when we must produce more, and at the same time impact on the environment less.”
The holy grail of a second, sustainable green revolution has been called the ‘evergreen revolution’ by some, including the ‘father of the Indian green revolution’, Mankombu Swaminathan.
Swaminathan has invested in a research foundation to trial modern, sustainable practices in new biovillages. They use the leguminous nitrogen-fixing plant Sesbania prostrate to fertilise soil, together sometimes with mineral fertilizers and chemical pesticides, in a way that he claims can maintain both environmental and social sustainability and economic viability (ref 19).
These methods have yet to be proven on large scales, but proponents make a case that such approaches have a place in research alongside other scientific endeavours like crop breeding and pest management.
Many of the issues highlighted are global problems. Meeting the world’s food security challenge will require a multi-national, collaborative effort to integrate the best research from science, engineering and socioeconomics so that technological advances can bring benefits where they are most needed.
References
Further materials are available in the resource centre.
- Cabinet Office: Food Matters: Towards a Strategy for the 21st Century
- BBC Special Report: the cost of food
- World Food Programme: Winning the war on hunger
- Bayer Cropscience: The second green revolution
- FAO: How to feed the world in 2050
- FAO Crop prospects and food situation 2009 (PDF)
- BBC Q&A: Caterpillars ravage Liberia
- Nature: Halting the African armyworm
- Julie Scholes’ presentation at workshop: Food security and sustainability – can we avert a food crisis?
- FAO Wheat Rust Disease Global Programme
- Cornell University: Rust Resistance in Wheat
- Disappearing food: How big are postharvest losses? (PDF)
- WRAP Down the drain (PDF)
- WRAP Household food and rink waste in the UK
- UN Water in a changing world (PDF)
- Water wars, Eureka #2, The Times
- UNEP Global Environment Outlook 3
- Andrew Dorward presentation at workshop: Food security and sustainability – can we avert a food crisis?
- Now for the evergreen revolution
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