By the year 2010, the population of the planet is expected to swell to around 7 billion, almost double what it had beer' just 40 years earlier. If present trends continue, nearly one person in 10, or some 680 million people, will skill suffer from chronic undernutntion. Reversing these trends without clearing and plowing vast areas of marginal lands and irreplaceable natural habitats will require rapid and sustainable gains in agricultural production - a new green revolution.
IN THE REGIONS inhabited by the majority of humanity, most land suitable for agriculture is already being farmed. Significant areas that could be opened up for agriculture do exist in Africa and Latin America. But most are covered by forest. Converting them for agriculture would take a heavy toll on indigenous forest dwellers, as well as on forest and savannah vegetation and biological diversity.
As food production must increase more than 75 percent over the next 30 years, most of the gains will have to be achieved by obtaining higher yields from land that is already being farmed.
Achieving gains of that magnitude will require widespread adoption of the technologies that today allow research stations to reap twice as much as farmers average. But steps must also be taken to avoid the social and environmental damage caused by a wholesale shift to monoculture production. A new green revolution will need to combine modern technology, traditional knowledge and an emphasis on farming, social and agro-ecological systems as well as yields.
Sources of grains in agricultural production
in developing countries 1988/90-2010
BEGINNING in the 1960s, improved, high-yielding varieties of wheat spread quickly across Asia, soon followed by new strains of rice. Within 20 years, almost half the wheat and rice land in developing countries was being sown with the new varieties. In Asia, where the impact of the green revolution was greatest, almost 90 percent of wheat fields were planted with modern varieties and plantings of high-yielding rice had increased from 12 to 67 percent.
In order to reap the potential of the new seeds, farmers also rapidly increased their use of mineral fertilizers, pesticides and irrigation. Between 1970 and 1990, fertilizer applications in developing countries shot up by 360 percent while pesticide use increased by 7 to 8 percent per year. The amount of land under irrigation increased by one-third. The gains in production were dramatic: world cereal yields jumped from 1.4 tonnes per hectare in the early 1 960s to 2.7 tonnes per hectare in 1989-91. Over the past 30 years, the volume of world agricultural production has doubled and world agricultural trade has increased threefold.
These rapid gains helped avert a major food crisis in Asia and provided the springboard for rapid economic growth in China, Southeast Asia and South Asia.
Cereal yield in kilograms per hectare
The green revolution of the 1960s and 1970s depended on applications of fertilizers, pesticides and irrigation to create conditions in which high-yielding modern varieties could thrive. It provided the basis for a quantum leap forward in food production. But it also taught scientists and policy-makers some important lessons for the future.
Reliance on seeds that have to be bought rather than saved from year to year and that require expensive inputs may exclude many poor farmers from the benefits of a green revolution.
In many areas, water is being pumped out of the ground for irrigation faster than it can be replenished. Up to 60 percent of the water withdrawn for irrigation may never reach the crop. Poorly managed irrigation causes waterlogging and salt buildup that can turn fertile fields into a wasteland. Salinity now affects more than 20 percent of the irrigated land in China and Pakistan.
Widespread use of just a few high-yielding varieties of wheat and rice may lead to the Loss of traditional varieties and increase vulnerability to pests and diseases. By the end of this century, as few as 12 varieties of rice may cover 75 percent of the fields in India.
The environmental damage caused by misuse of fertilizers and pesticides sometimes outweighs their advantages. Experts estimate that only about half of the fertilizer used may actually benefit the crops; the remainder is lost from the soil by leaching, run-offend volatilization. Similarly, a large percentage of pesticides may not reach target pests. Instead, they contaminate people, land, water and air, and foster the emergence of resistant strains of pests.
To achieve sustainable advances and minimize negative side effects, a new green revolution must also invest in education, farm management, information and training.
Countries that have achieved greater national and household food security generally have a track record of strong support to agriculture, careful considerations of economic incentives for agricultural production, and human and economic investments in research, extension and training. To spark a new green revolution, national governments will need to work with civil society and the private sector in several key areas, including:
THE NEW green revolution draws on the best of the technologies that have doubled production over the past 30 years. At the same time, it emphasizes alternative approaches and improved farm management and information systems in order to minimize environmental damage from external inputs and benefit poor farmers and marginal areas bypassed by the original green revolution.
Examples of such approaches include:
Increasing food production in the better endowed areas can reduce pressures for expansion into marginal and more easily degraded lands.
Much attention must also be given to less fertile areas, where many of the poor and undernourished live. Here, a new green revolution must create more productive farming systems, including mixed crop-livestock systems that blend farmers' traditional techniques with new knowledge in crop and animal husbandry.
TYPICALLY dryland farmers obtain less than half the yields that research stations can achieve under similar conditions. In Andra Pradesh, India, for example, research scientists have achieved impressive gains by double cropping grain and pulses (see diagram below).
Some rice farmers in South-East Asia have recently neared research station yields. But further scientific advances could push yields higher. The International Rice Institute aims to achieve annual yields of 15 tonnes per hectare, compared with the current world average of 3.5 tonnes.
Yield gaps in the field - an example
Substantial gains could also be achieved in livestock and aquaculture production. In tropical aquaculture, genetic improvements in carp and tilapia have led to yield gains of up to SO percent at the farm level over the past five years, offering hope for available and affordable protein.
If average annual farm yields per hectare could approach two-thirds of research station yields under comparable climatic conditions, enough food would be available to feed the hungry millions of tomorrow.
Farmer's yields as a percentage
of research station yields
For further information, please contact:
Food and Agriculture Organization of the United Nations
Viale delle Terme di Caracalla, 00100 Rome, Italy
Information Division, Tel: (39-6) 5225-3276/5225-4781/5225-4243
Sustainable Development Department, Tel: (39-6) 5225-3363
Internet, http://www.fao.org or gopher.fao.org