Rice provides 23 percent of all calories consumed globally. Traditionally, hundreds of varieties have been cultivated but growing urban populations and the green revolution mean that farmers now produce large quantities of a few high-yield varieties. This means cheap rice but it requires high-cost inputs. Inputs are one of the reasons why rice production has high environmental costs. What can be done to reduce the environmental impacts of rice without threatening food security?

Research from the WWF looks at global production patterns for rice. Rice production is divided into two main types, upland and lowland. Lowland rice is irrigated whereas upland rice relies on rainfall. The production techniques of the green revolution, which have led to dramatic increases in productivity, have mostly been applied to lowland, irrigated rice.

There is some uncertainty about whether modern rice production is sustainable. The price of high-input rice has been low for some time, but this will not last forever. Rice farmers are dependent on fertilizers and pesticides, and costs are increasing all the time.  The price of the labour is also going up, especially in Asia. Furthermore, green revolution irrigated rice is beginning to show declining yields – the main causes being  different forms of environmental degradation, including increased pests and diseases and the depletion of soil nutrients.

The research shows:

• Rice production is a monoculture activity, with several crops grown each year. This has significantly reduced biodiversity in the production system, from microbial life right up through the food chain.
• Fertilizer use in rice production has a negative effect on water quality. In some places, only 30 percent of the fertilizer applied to the crop is actually absorbed. The rest washes  into rivers and lakes, which has a major polluting effect.
• Rice production uses a vast range of pesticides which disrupt ecological processes and poison people. Studies in Thailand, for example, show that pesticide residues exist in 90 percent of samples of soil, river sediment, fish and shellfish.
• Rice production is a large and inefficient consumer of water. The impacts of water withdrawal for rice on biodiversity and ecosystem functions are not well understood, however.

There are many ways to reduce the environmental problems associated with different rice production systems, but each producer must decide which are the most important impacts to reduce, and the best way of achieving this.

• Rice can be irrigated and cultivated alongside other crops. New multi-crop (polyculture) technologies could eliminate the need for converting land for flood irrigation.
• Integrated pest management can reduce the use of pesticides whilst maintaining yields.
• There are several strategies for making fertilizer use more efficient. Two of the most important are to increase organic matter in the soil and reduce nutrient loss associated with water runoff.
• Rice fields can be managed as wildlife habitats if farmers are encouraged to pursue conservation strategies or if they understand the financial benefits.

Certain systems of rice cultivation are more productive than others and have fewer environmental impacts. Many of these are particularly appropriate for smaller producers.  They should be supported not only to protect the environment, but also to help to achieve food security and poverty reduction.

Source(s):
‘World Agriculture and the Environment: a commodity-by-commodity guide to impacts and practices’ Island Press and WWF-USA, by Jason Clay, 2004

Funded by: World Wildlife Fund; Ford, MacArthur, Avina and Packard Foundations, Pew Charitable Trusts, Interchurch Organisation for Development Co-operation, World Bank, Food and Agriculture Organisation, Inter-American Development Bank.

id21 Research Highlight: 1 February 2005

Further Information:
Jason Clay
Centre for Conservation Innovation
WWF-USA
2253 North Upton Street
Arlington, VA 22207
USA

Fax: +1-(0)-703-524-0471
Contact the contributor: jason.clay@wwfus.org

WWF

Other related links:
'Counting the cost of a cup of coffee'

'Searching for sustainable cotton production'

International Rice Research Institute

Rice Web