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close this bookReversing the Spiral - The Population, Agriculture, and Environment Nexus in Sub-Saharan Africa (WB, 1994, 320 p.)
close this folder4. The Nexus of population growth, agricultural stagnation, and environmental degradation
View the documentThe main linkages
View the documentTraditional crop cultivation and livestock husbandry methods
View the documentLand and tree tenure systems and the Nexus
View the documentDeforestation, fuelwood, and the Nexus
View the documentLogging
View the documentNotes
View the documentAppendix to chapter 4

The main linkages

The preceding chapter cited evidence suggesting that agricultural stagnation and environmental degradation, combined with customary land tenure systems and the traditional roles of rural women, may contribute to maintaining high fertility rates. These systems and practices appear to create demand for child labor as a means to ensure family survival. The difficulties faced in analyzing these relationships are rooted in the multiplicity of factors that affect the rate of population growth, environmental degradation, and the pace and direction of agricultural development in Sub-Saharan Africa In addition, there are important variations across countries. This chapter pursues the analysis of multiple and synergetic links between rapid population growth, poor agricultural performance, and environmental degradation. The role of women in rural production systems, a major link in this nexus, is discussed separately in Chapter 5.

The complexity of these linkages and the seeming ambiguity of the analysis result primarily from Boserup's finding that agricultural intensification occurs as population density on agricultural land increases (Boserup 1965). Others have published more recent materiel confirming the applicability of the Boserup hypothesis to many developing country situations, including in Sub-Saharan Africa (for example, Binswanger and Pingali 1984,1988; Pingali, Bigot and Binswanger 1987; Lele and Stone 1989). It should not be surprising that this phenomenon has been observed so widely Farmers are unlikely to have an incentive to intensify their agricultural production (i.e., to generate more output per unit land area) unless there is a constraint on land If there is no land constraint, and land is free or very cheap, it makes sense from the fanner's perspective to extend the use of land and minimize the use of other inputs, including capital and labor. Shifting cultivation and pastoral livestock raising are perhaps the best illustrations of this situation. They have predominated in most of Sub-Saharan Africa.

Box 4-1 Ukara Island, Lake Victoria (Tanzania): Agricultural Intensification under Population Pressure

An extreme example of agricultural intensification underpopulation pressure is that of Ukara island in Lake Victoria. Faced with considerable population pressure and soils of low fertility, the island's inhabitants, the Kara (or Wakara), had developed, prior to European contact, a highly refined intensive farming system, which included erosion control, crop rotation with intercropping and green manuring with legumes, fodder cultivation, stabling of cattle, and fertilizing of fields (farmyard manure, leaf manure, household ash). The tenure system was based on private property, with inheritance and sale of land. The system has, however, reached its limits. The island's population has numbered about 16,000 since the beginning of the century; population density is about 500 per km², and the average family holding amounts to 1 hectare of arable land. There has been little, if any, population growth, whereas there has been substantial population growth in the rest of the Lake area where shifting cultivation is still practiced. Excess population moves to the mainland, where labor-intensive techniques are quickly abandoned because the returns to labor are far higher with the extensive systems still possible on the mainland (Ludwig 1968; Kocher 1973, Ruthenberg 1980:158-160; Netting 1993:52-53).

Consistent with Boserup's findings, these customary extensive farming and livestock systems change when populations become more dense This can be seen in the Kenya highlands, Burundi, Rwanda, the Kivu Plateau in eastern Zaire, and in parts of Nigeria. In Rwanda in particular, intensive traditional agricultural systems exist, brought about by the scarcity of land relative to the population dependent on it. In most of Sub-Saharan Africa, however, land has been abundant until recently, and in some countries it still is.

Traditional crop production and animal husbandry methods. traditional land tenure systems and land use practices, traditional methods of obtaining woodfuels and building materials, and traditional responsibilities of women in rural production and household maintenance worked well and could evolve slowly when population densities were low and populations were growing only slowly The hypothesis is that rapidly increasing population pressure in the past twenty to thirty years has, in most of SubSaharan Africa, overwhelmed the only slowly evolving rural traditions of farming, livestock raising, fueIwood provision, land allocation and utilization, and gender-specific responsibilities in household maintenance and rural production systems This has led to an accelerated degradation of natural resources. And this in turn has contributed to the low rate of growth of agriculture. In those few places where agricultural intensification has occurred most rapidly, there has been very riffle, if any, degradation of natural resources.

Box 4-2 The Kofyar in Nigeria: Extensive Farming When the land Frontier Opens

The Kofyar initially lived as subsistence farmers on the Jos Plateau in northcentral Nigeria. As population density on the escarpment increased, they intensified their farming system, with increasing reliance on agroforestry, terracing, and manuring. When population growth on the plateau outpaced the ability of their farming system to sustain the increased numbers, the Kofyar obtained permission from tribes in the Benue River plains to clear low-land forests and farm there. The migrants abandoned the intensive farming techniques they had practiced on the plateau and adopted instead an extensive forest-fallow farming system focused on cash cropping and market-oriented animal production. The subsistence farms on the Jos Plateau had averaged about 15 acres, while the new farms in the cleared forests were 4 to 5 times that size (Netting 1968; Stone 1984). However, over a period of about thirty years, as population density in the newly developed lowlands increased, the settlers gradually intensified their farming methods again (Netting 1993).

The complexity of these multiple interrelationships is further increased by interaction with the economic policy environment characterizing many African countries since the mid-1960s. Exchange rate, tax, trade, and agricultural price policies in many African countries have often combined to render agriculture unprofitable. The mechanisms for developing and trsnsmitting improved agricultural technology are severely inadequate throughout Sub-Saharan Africa. Excessive government control of agricultural marketing and processing has either squeezed out the private sector or forced it to operate clandestinely, yet public sector marketing; and processing enterprises have performed poorly Farmers have not usually been permitted to associate freely in farmer-managed cooperatives, nor to market freely their products Throughout Sub-Saharan Africa, this lack of empowerment of farmers has discouraged them from investing To break out of the trap of rapid population growth, low agricultural growth, and environmental degradation, these policy constraints must be overcome. The World Bank's 1989 long-term perspective study on Sub-Saharan Africa suggested how this might be done (World Bank 1989d). Reversing the Spiral contends that measures will also be needed to overcome the constraints imposed by increasing population pressure on traditional cultivation, fuel provision, and tenure systems, and by the roles customarily assigned to women in rural societies. Appropriate policy reforms will make the more rapid evolution of these traditional systems easier.