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IFPRI report

Irrigation technology and commercialization of rice in the Gambia


Effects on income and nutrition


Joachim von Braun, Detlev Puetz, and Patrick Webb


Editor's note

This study is part of a larger ongoing effort at IFPRI aimed at improving understanding of the effect of technological change and commercialization at the household level. Studies following a similar approach have been undertaken by IFPRI in Kenya, the Philippines, Rwanda, and Guatemala.


Technological change in African agriculture is usually necessary, but not always sufficient, to achieve sustained increases in production. How can technical progress in a crop-and the resulting local growth in marketed surpluses of that crop (that is, the commercialization of traditional agriculture)-be designed and complemented so as to improve the chances of African countries to (1) raise the aggregate output of crops, and (2) reduce poverty, improve food consumption, and advance nutrition, especially among vulnerable pre-schoolers?

This study examines such questions in the setting of a major technical improvement in rice production in a West African country. It asks: To what extent does technical change raise production? Does such change encourage the diversion of labour from other activities into modern rice or into leisure as income rises? If extra production does materialize, does it increase income and consumption? If so, do the poor benefit from this? Does any such extra consumption affect adult and child nutrition? The links between production, income, consumption, and nutrition are explicitly established in the analysis.

The study focuses on a new rice-irrigation project involving about 7,500 farmers in the Gambia. The study site was selected because households could be traced during and after the introduction of new rice production technology (mechanical-pump irrigation and improved drainage for rain-fed and tidal irrigation).

The empirical research is based on a detailed sample survey of 900 farmers in ten villages. This sample included both participants and non-participants in the irrigation project and covered the four major ethnic groups of the area, thereby providing a fair degree of representativeness for a wider part of the West African region, especially major parts of Senegal and Guinea. Account is taken of the complexity of production-consumption relationships in the large households that are typical of the region.

Production in the project takes place under fully water-controlled conditions (pump irrigation and drainage) that provide two crops per year, and also under partly water-controlled conditions (tidal irrigation or improved rain-fed cultivation and drainage) that provide only one crop (in the wet season). Wet season yields in the fully water-controlled perimeters were 6.6 metric tons per crop per hectare in 1984 but dropped to 5.2 tons in 1985. In the same two periods, the partly water-controlled rice yielded 2.2 and 2.8 tons respectively. Traditional rain-fed rice (predominantly a women's crop grown in swamps) yielded 1.3 tons. Great variation in costs and net returns is observed between the technologies and between individual farmers using the same technology.

Average and marginal labour productivities are assessed in the context of the production system for the major crops. Average labour productivity (net returns per labour day) was highest for rice under pump irrigation (US$2.45), followed by coarse grains (US$1.50), groundnuts (US$1.45), rice in the partly water-controlled project fields (US$1.23), and traditional swamp rice (US$0.95).

Most farmers at the project location grow both irrigated rice and upland crops. The expansion of modern irrigation has pulled labour away from the upland crops, causing a loss of 531 calories in other crops for every 1,000 calories gained in rice production-a net gain of 47%.

Men's overall labour input into agriculture is reduced when the household has more land in the project. Women's labour input, on the other hand, remains more or less constant. Hired labour accounts for 25% of the work in the pump-irrigated plots. Since hired labour played only a marginal role in rice production before the project, this reflects an increased use of hired labour in rice as a phenomenon associated with commercialization.

There was a specific attempt in this programme to ensure access to project land by women, the traditional rice producers. Formal land titles for plots were given to female farmers. Yet the results were not as planned. Women continue to control 91% of traditional swamp rice fields, and even 77% of the partly water-controlled fields, but they control only 10% of the pump-irrigated plots.

Less of the new rice crop is sold for cash than was expected-12%% of total production from pump irrigation and 7% from partly water-controlled land. This compares with women's traditionally grown swamp rice, of which 21% is sold. This pattern of women selling relatively more than men is explained by the different institutional arrangements under which the crops are grown. The high-technology rice in the project has largely become a communal food crop for the common household pot under the compound head's control, while women's traditional rice is a mixed private crop (partly grown for cash) and communal food crop.

Protecting and enhancing women's productive role in agriculture is an important objective in itself. It is also important as an indirect path toward nutritional improvement. The study finds, however, that this objective cannot be enforced through bureaucratic means (formal land titles), which have little relevance in the field.

Average annual per capita income in the study area was US$116 in 1985/86; agricultural income contributed 77.5%. Rice production in the project contributed 43.0% of income to the bottom income quartile (income per adult equivalent) versus 26.0 %% to the top quartile. The poor households thus benefited relatively more than did the upper-income groups in the area. At the sample average, the rice in the project increased real incomes by 13.0% per household.

An additional 10.0% of income leads to a 9.4% increase in food expenditures and a 4.8% increase in calorie consumption. The seasonal fluctuation in per capita calorie consumption is a problem of the poor and not of the total rural population. In the bottom income quartile, calorie consumption was 15.0% lower in the wet (hungry) season than in the dry season, but it remained constant and, indeed, sufficient in the top quartile. In the wet season, 49.0% of households in the bottom quartile consumed less than 80% of calorie requirements; only 2.0% of the top quartile fell below that level.

In the wet season, 35% of children under five years of age and 52% of those aged one to two years were found to be underweight. Lack of food, unclean water, and infectious diseases are identified as important determinants of nutritional status in multivariate analyses. Mothers' nutrition and health are considerably affected by seasonal work stress.

Household-level calorie consumption is a determining factor for differences in the nutritional status of children in the study area. A 10.0% increase in calorie availability per capita increases the weight-forage indicator of nutritional status by 2.4% at sample means. This calorie elasticity of nutritional improvement is even higher in households with higher calorie deficiencies. To the extent that the new technology has increased household income, and thereby calorie consumption, and to the extent that mothers' seasonal stress has been reduced, the nutritional status of children and women has improved.

The study implies a set of policy conclusions for improved technology utilization, food security, and nutrition. A more broad-based policy and programme emphasis on improvements in rural infrastructure, agricultural input delivery systems, and labour-saving technology for the peak season is called for rather than a focus on a single crop.

Rice irrigation shows promising potential in the study area, but the issues of technology choice and project design are complex. Specific suggestions related to choice of rice-production technologies demonstrate opportunities for cutting costs in the respective technologies.

Measures are proposed to protect and enhance women's productive role in agriculture; for example, women's role as cash croppers and their lack of credit require more attention.

From a food-security perspective, a wide distribution of small irrigated rice plots is needed across households and village communities in the area to reduce the adverse effects of seasonality and consecutive drought years on consumption. However, such scattered distribution of the highly productive irrigated land results in fluctuating yields, since in years of good rainfall labour is allocated more heavily to upland farming, while in drought years labour shifts more to the irrigated fields. Thus, good rainfall years appear bad for production in irrigated farming surrounded by upland farming, with large year-to-year fluctuations of labour productivity. In the absence of a well-developed rural financial market, the food security benefit of scattered land distribution (rather than creation of larger specialized rice farms) should be an important consideration despite the instability it induces in irrigation projects and the related project-management burdens.

Finally, the study suggests that efforts to solve the nutrition problem can be furthered through more effective rural health services and sanitation (that is, drinking water) at the community level. The interactions between food shortage and morbidity, which establish the high prevalence of malnutrition in this study area, cannot be dealt with effectively from the food supply side only. The nature of the nutrition problem requires a strong focus on women (mothers) rather than on young children alone.


Book reviews and notices

Women's role in food chain activities and the implications for nutrition. Gerd Holmboe-Ottesen, Ophelia Mascarenhas, and Margareta Wandel. ACC/SCN State-of-the-Art Series, Nutrition Policy Discussion Paper no. 4. ACC/SCN, Geneva, 1989. 110 pages.

This report was prepared for the symposium "Women and Nutrition" at the SCN's fifteenth session, in February 1989. Its main aim is to give an account of the state of the art of research related to women's role in food production and nutrition and to discuss the practical implications of these findings.

The report contains 11 chapters, which are written so that they can be read independently. It focuses on the constraints and potentialities for women in providing adequate nutrition and health care for their families, in catering to their own nutrition and other basic needs, and in areas of conflict and congruence between these facets of the women's role. An annotated bibliography contains 111 references related to women's roles and tasks in the food chain-which include food production, food processing, and food distribution-and their implications for household nutrition as well as women's own nutrition, health, and social status and the quality of their lives. The main emphasis in the report is on Africa and Asia although the bibliography includes some studies from other regions.

Information on the ACC/SCN State-of-the-Art Series, as well as copies of papers, can be obtained from the ACC/SCN Secretariat. Inquiries should be addressed to: Dr. John B. Mason, Technical Secretary, ACC/SCN, c/o World Health Organization, 20, Avenue Appia, CH-1211 Geneva 27, Switzerland.

Requirements of vitamin A, iron, folate, and vitamin B12. Report of a joint FAO/WHO Expert Consultation. FAO Food and Nutrition Series, no. 23. FAO, Rome, 1988. 107 pages.

In 1965 the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) convened an expert group to review human requirements for vitamin A, thiamine, riboflavin, and niacin. In 1969 the two organizations convened another expert group on the requirements for ascorbic acid, vitamin D, vitamin B12, folate, and iron. The reports from these two groups stressed that sufficient information was not always available to make it possible to specify exact nutrient requirements under diverse physiological and environmental conditions or to answer other questions unequivocally. It was realized that the recommendations could only be tentative and would be subject to revision in the future.

During the past two decades a wealth of new information has become available, both on the requirements for these nutrients and on interpretations and applications of recommended intakes. FAO and WHO therefore convened another expert consultation to review vitamin-A, iron, folate, and vitamin-B12 requirements in consideration of their importance for public health, as evidenced by the high prevalence of vitamin-A deficiency and resulting xerophthalmia, and of nutritional anaemia, especially in the developing world. The meeting was held in Geneva, 1322 March 1985.

This report argues for major changes in the estimation and interpretation of human requirements for vitamin A, iron, folic acid, and vitamin B12. It may be some time before the full import of these changes is recognized. The new estimates of requirements for all of the nutrients except iron and vitamin A in the case of children tend to be lower, sometimes significantly lower, than those in the earlier reports. This is in keeping with the trend seen in many national dietary standards. Undoubtedly it reflects an improved data base for the estimation of requirements and, with that, a move to eliminate the "margin of safety" embodied in earlier reports, when the tendency had been to increase the requirement estimate if there was doubt.

Three major developments in the description and interpretation of requirements are reflected in the present report that are essentially absent in the earlier reports. The first is the attempt to describe different levels of requirement and different needs. The second is the increased emphasis on the distribution of requirements rather than a single point arbitrarily defined as the recommended or safe level. These have major implications for the interpretation of requirements. Finally, although not specifically addressed in the present report, the approach to comparison of recommended intakes with per capita intakes or supplies has been abandoned. The relevant sections of the previous reports are now seen as seriously flawed in the light of concepts presented in the introductory sections of the present report.

The establishment of multiple levels of requirement, as presented in this report, also provides the user with the opportunity to decide on the "health" goal to be achieved in either individual counselling or programme planning. For example, in dealing with iron, the opportunity is provided to consider iron needs for the control of anaemia or for the satiation of all known body functions requiring iron. The levels of intake required to achieve these two goals are different. So too are the potential logistic and cost implications. The onus is now placed on the user, rather than the expert consultant, to make choices appropriate to the situation.

New seeds and poor people. Michael Lipton, with Richard Longhurst. Johns Hopkins University Press, Baltimore, Md., USA, 1989.473 pages. US$35.00

The impact study reported in this book was designed to assess how far the work of the fourteen International Agricultural Research Centres (IARCs), which concentrate almost entirely on food production, have been appropriate, technically and socio-economically, for improving the position of farmers, workers, and consumers in less-developed countries. In practice the study could not distinguish between the impact of the international centres and of the national agricultural research centres with which they interact.

The main life-saving effects of the introduction of modern varieties of crops by the international and national centres have come from the additional employment provided for poor workers and the restraining effect of the new varieties on the price of food to poor households. The book concludes, however, that the benefits have been relatively small and that the modern varieties have seldom overcome the institutional obstacles that direct their benefits to the better off. Despite the introduction of modern varieties, the living standards of the poor in South Asia have been virtually stagnant, and the varieties have been slow to spread among the poor despite their deepening poverty.

Among the reasons identified for their slow adoption by the poor are lack of access to controlled water, the planners' deep ignorance of smallholder's food farming practices and constraints, unreliable data on food production and imports, lack of infrastructure for food exchange, land scarcity, varieties poorly adapted for poor farmers' needs and opportunities, lack of national commitment to a sound agricultural policy. Much has been achieved by agricultural researchers who have developed these new varieties. The persistence of mass poverty in some developing countries-whether with or without the adoption of modern varieties of crops-should be blamed on socio-economic structures and associated policy, not on the agricultural researchers. However, in many instances the research could have been better targeted to the needs of the poor.

A brief review cannot capture the complexity of the problems of poor agriculturalists in developing countries as they relate to the successes and failures of the Green Revolution. The book does an admirable job of identifying the issues and dissecting them critically. Its conclusions are bound to disappoint those agencies supporting both this study and the international centres, but they also point the way to making the Green Revolution more effective in helping the poor of developing countries.

The poor in Latin America during adjustment: A case study of Peru. Paul Glewwe and Dennis de Tray. Living Standards Measurement Study Working Paper no. 56. The World Bank, Washington, D.C., 1989. 46 pages. US$5.95

This is a working paper published informally by the World Bank at a time when many of the world's poorest countries are being forced to undergo structural adjustments in order to satisfy the demands of the international lending agencies and banks. The impact of adjustment policies has been particularly severe in Peru and several other Latin American countries.

The analysis suggests that correcting economic distortions may have little direct effect on the poor in either rural or urban environments. The important finding is that government programmes and policies can be changed in ways that would benefit the poor and, in some cases, reduce overall public-sector expenditures.

It is available through the Publications Sales Unit, Department F, The World Bank, 1818 H Street, N.W., Washington, DC 20433, USA; or 66, avenue d'Ična, 75116 Paris, France.

Improving young child feeding in eastern and southern Africa: Household-level food technology. Proceedings of a workshop held in Nairobi, Kenya. International Development Research Centre, Ottawa, Ont., Canada, 1988. 380 pages.

Food scientists, nutritionists, and health planners working in Africa and South Asia met to examine household-level food technologies that hold promise for improving the nutrition of infants and young children in the region. By the end of the second year of life, one-third of children in eastern and southern Africa are chronically malnourished. The workshop reviewed current knowledge of breast-feeding practices in eastern and southern Africa and the use of fermented food and germinated flour in weaning diets, both to improve nutrient intake by young children and to decrease the risk of food contamination.

The book has five sections, dealing respectively with issues involved in improving child feeding, current weaning practices and needed change, the use of fermented food in child feeding, food contamination, and experiences with child feeding in the region. It contains valuable information for anyone concerned with the feeding of the weanling child under conditions prevailing for the poor in developing countries.

Copies in either English or French can be obtained without charge by writing to the International Development Research Centre (IDRC), P.O. Box 8500, Ottawa, ON K1G 3H9, Canada.

Safe food handling: A training guide for managers of food service establishments. M. Jacob. World Health Organization, 1211 Geneva 27, Switzerland, 1989. 48 pages. SwF 25; US $20. (Available in English. French and Spanish editions in preparation.)

This book provides a point-by-point guide to measures that can be used in the food-service industry to prevent food contamination and protect consumers from food-borne disease. Addressed to managers and supervisors in hotels restaurants, and other catering establishments, the book responds to scientific knowledge indicating that most outbreaks of food-borne disease can be traced to well-defined errors in food preparation and storage. With this in mind, the book concentrates on facts and advice that can be used to teach food handlers both the principles and the specifics of good hygienic practice. Readers are also reminded of the high costs of food-borne illness, including lost clientele and damage to tourism, and of the protection achieved when food handlers are taught to avoid common errors. The book concludes with advice on using the guide in planning and conducting training sessions for staff.

Public health nutrition, and other bulletins of the International Children's Centre, Paris.

The International Children's Centre (Centre International de l'Enfance) publishes a series of bibliographic bulletins on a variety of specialized themes, containing abstracts that provide accessible, rapidly usable information. The bulletins include:

Two issues of each bulletin appear yearly.

The bulletin on public health nutrition has been published since 1976, with approximately 100 abstracts per issue. It contains a subject index, a geographic index, and a list of the periodicals reviewed. As is true for all of the bulletins, the abstracts deal with the main methodological points, findings, and conclusions of the articles, and the original documents can be obtained by written request to the centre.

The centre also has a computerized information base (BIRD), which can be consulted on the premises or by correspondence. BIRD is based on key words, contains 90,000 references, and is growing by about 5,000 references per year.

Requests for information or to be placed on the mailing list for any of the bulletins should be addressed to: Centre International de l'Enfance, Chateau de Longchamp, Bois de Boulogne, F-75016 Paris, France.

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