|Sustaining the Future: Economic, Social, and Environmental Change in Sub-Saharan Africa (UNU, 1996, 365 pages)|
|Part 1: Economy and society: development issues|
|Introduction to population, resources, and sustainable development in Sub-Saharan Africa|
Internal and international migration
Population, agricultural land, and food supply
Population, economy, and sustainable development
John O. Oucho
The demographic structure of Sub-Saharan Africa in all its complexity is a considerable subject. This paper will therefore focus mainly on the major subcontinental and regional features of Sub-Saharan Africa's demography and will provide a brief introduction to the subject to serve as a foundation on which other more detailed discussions of poverty, development, sustainability, and resource management may rest. Many of the topics relevant to demography, such as urbanization, urbanward migration, natural resources, and environmental sustainability, have specialized treatment elsewhere in this collection of conference papers, and will receive only preliminary or partial treatment here.
Amongst the major regions of the third world, Sub-Saharan Africa has one of the smaller populations in total, at an estimated 543 million in mid-1992 (World Bank 1994: 163), more than Latin America and the Caribbean but much less than either South Asia or East Asia and the Pacific. It shares with Latin America and the Caribbean a very low population density of only 22 per km2, compared with 229 in South Asia and 103 in East Asia and the Pacific. However, in contrast with Latin America and the Caribbean, there are few great urban concentrations and virtually no major industrial regions outside South Africa. A much higher proportion of its population is rural (71 against 27 per cent) and widely dispersed, a feature of considerable significance in its economic development. Sub-Saharan Africa's population is one of the poorest and depends in many of its subregions on fragile tropical environments, for whose sustainable management its peoples often lack the skills required to cope with current economic and technological changes. There is also the problem of increasing pressure on resources generated by the highest rate of population increase in the world apart from that of the Middle East and North Africa - 3.0 per cent per annum in 1980-1992 against 3.1 per cent (World Bank 1994: 211).
Population structure and characteristics and their relation to the resources for sustainable development will be examined largely at the subregional and national level. Table 4.1 shows some of the basic demographic data for Sub-Saharan Africa estimated in 1990 (Population Reference Bureau 1990). The largest population of the subregions was in western Africa, with 206 million or 39.8 per cent of the estimated total of 518 million. Eastern, central, and southern Africa had 38.4, 13.1, and 8.7 per cent respectively. Doubling time for most of the subregions was estimated to be 23 years. Projected populations for Sub-Saharan Africa were nearly 702 million with approximately the same subregional balance by the year 2000, and 1.2 billion by 2020. Some differential size changes will occur, mainly by countries, reflecting different rates of population growth - three of the four subregions recorded the same rate of natural increase and doubling time (table 4.1, columns 2-5). In western Africa, half the countries listed had annual natural increase rates of 3 per cent or more, as did more than two-thirds of eastern African countries (at 3.8, Kenya and Zambia had the highest rates in Sub-Saharan Africa), while in central and southern Africa rates tended to be lower. As might be expected, very high total fertility rates (TFR) are widespread, with 13 countries listed as having 7.0 or more births per woman. Rwanda has the remarkable figure of 8.3, one of the highest in the world. It should be noted that, although there is some variation in the country-level data between published sources, all agree that Sub-Saharan Africa currently has the highest rates. Although Sub-Saharan Africa succeeded in reducing its infant mortality rate (IMR) from 142 per 1,000 live births in 1970 to 99 in 1992, compared with a reduction from 97 to 60 in the world IMR (World Bank 1994: 215), most of the countries in table 4.1 had IMRs above 100 (column 8), putting some brake on population growth. Very high IMRs were recorded in Sierra Leone, Ethiopia, Guinea, the Gambia, the Central African Republic, and Mozambique.
Table 4.1 Demogruphic indicators: Estimates and projections for Sub-Saharan Africa by subregion and country, 1990
|Subregion/country||Population estimate, mid-1990 (million)||Birth rate (per '000 pop.)||Death rate (per '000 pop.)||Natural increase (annual, %)||Population"doubling time" in years (at current rate)||Population projected to 2000 (million)||Population projected to 2020 (million)|
All types of internal migration (rural-rural, rural-urban, urbanurban, and urban-rural) and international migration (permanent, labour, refugee, and undocumented/illegal) are represented in SubSaharan Africa, but only the broad outline of population movement can be discussed here.
The two dominant forms of internal migration are: the less studied but more diverse rural-rural migration and the more studied and pervasive rural-urban. Rural-rural migration consists of:
1. nomadism, especially in the Sahel, the Horn of Africa, northern Kenya, northern Tanzania, north-eastern Uganda, Botswana, and Namibia (Oucho and Gould 1992);
2. spontaneous migration for purposes of land colonization by farmers (e.g. in Kenya, Zimbabwe, and revolutionary Ethiopia, and in Tanzania during "uiamaa");
3. resettlement of peasants from densely occupied areas to marginal lands, and migration from areas of traditional agriculture to areas of modern agriculture or to mining areas.
Approximately 29 per cent of Sub-Saharan Africa's population was estimated to be urban in 1992 (World Bank 1994: 223), but the definition of "urban" varies between countries. African cities generally lack strong economic bases, often attract rural-urban migration in the face of widespread unemployment (Todaro 1969, 1976), lack decent housing (Ohadike and Teklu 1990), and have overburdened educational and health facilities (Gould 1990; for discussion of rural-urban links see Oucho 1985, 1988, 1990). Attempts by many Sub-Saharan governments to limit or control rural-urban migration have mostly failed. The nature and magnitude of internal migration and the problems of spatial distribution of population are demonstrated by the fact that in 1987, out of 45 countries, 28 perceived both to be inappropriate and 26 adopted policies to decelerate the processes involved (UN Department of International Economic and Social Affairs 1988).
International migration in Sub-Saharan Africa has two dominant forms: labour migration and refugee movements. In western Africa, labour migration mostly has a north to south alignment, particularly to Cote d'Ivoire, and a south to north flow outside the continent to Europe (Adepoju 1991) and the Gulf states. In Sub-Saharan Africa, migration has involved flows mainly from weaker to stronger economies, such as, in western Africa, to Cote d'Ivoire (where by 1975 some 22 per cent of the population were foreign born), Nigeria, Liberia (21 per cent foreign born in 1974), Equatorial Guinea, and Gabon, and, in central and southern Africa, mainly to Zambia and South Africa (Bohning 1981; UN Economic Commission for Africa 1988). In western Africa, labour migration has sometimes precipitated sour relations between some countries, e.g. between Ghana and Nigeria (Afolayan 1988), ending in the repatriation of between 0.5 and 1 million Ghanaians in 1983. Many of these were from Nigerian towns and were forced back into rural areas in Ghana.
Apart from economic refugees, as in Ghana, most Sub-Saharan refugees have been and are still being forced to move by civil war or by drought. Many millions in the Sudan, Ethiopia, Uganda, Rwanda, Liberia, Mozambique, Angola, and Namibia are still displaced. However, the refugee flows also include movements back home, as in Uganda, where rehabilitation programmes have been undertaken, in recently independent Namibia, and in Mozambique and Angola.
There are many different ways to classify natural resources. The classification used here is a simple ad hoc method related to the link between natural resources and population, beginning with land as the basic resource for agricultural production, which is the most important element in many Sub-Saharan economies.
Table 4.2 provides broad land-use categories, from which it can be seen that Sub-Saharan Africa is nearly 34 per cent pastoral, 30 per cent forest and woodland, and just under 7 per cent cropland (which also supports large numbers of trees) (World Resources Institute 1994: 284). Another 30 per cent is "other land" - a small part urban and roads, and the rest chiefly sand, rock, and poorly vegetated terrain. Because Africa as a whole has 16 per cent of its soil area without "serious limitations" (FAO 1980: 4) it would seem probable that the cropland area could be considerably expanded (of these soil limitations, the most serious in Africa was drought, affecting 44 per cent, followed by nutritional deficiency or chemical toxicity, affecting 18 per cent). However, the demand for cropland is highly variable and some countries have little room for expansion. The highest proportions of cropland and permanent pasture are in western and eastern Africa, and the highest percentages of cropland by country are in Burundi (52.3), Mauritius (52.2), Rwanda (46.9), Nigeria (35.4), and Uganda (33.7). These three countries, particularly Rwanda, have little scope for the expansion of agricultural production other than by intensification. It is worth noting that some of the countries with advanced commercial agriculture, e.g. Kenya and Zimbabwe, have only low to average proportions of cropland, although Kenya does have a considerable area with serious environmental limitations.
In many Afriean countries, small family farms are the basis of agricultural production and the amount of cropland per capita tends to be low. In 1991, Africa as a whole had an average of 0.27 hectares per capita - nearly twice the Asian figure and less than half that for North and Central Ameriea, but the same as for Europe. Botswana had most cropland per capita, with 1.10 ha, but very low figures were recorded in Kenya (0.10), Guinea and Somalia (0.12), Tanzania (0.13), and Liberia (0.14) (World Resources Institute 1994: 294-295). Pressure on land resources has led to increasing individual ownership of land in place of traditional use right systems and associated with the growing commercialization of agriculture (Migot-Adholla et al. 1991).
Apart from the southern subtropical extreme and the more temperate conditions of the high plateaux and mountain environments, especially in Ethiopia and elsewhere in eastern Africa, temperatures are high throughout Sub-Saharan Africa and winter as such is nonexistent. Climatic types range from hot-wet to hot-dry; i.e. the main seasonal variations concern rainfall and humidity. The regularly arranged climatic regions each side of the equator have been a factor in north-south population movements and constitute a major resource on which most productivity depends. Sub-Saharan Africa has abundant sunshine throughout the year and therefore has substantial solar energy, utilized so far mainly by indirect means, chiefly in agriculture and in biomass energy sources such as fuelwood or crop plant waste. Solar energy is the greatest potential source of renewable energy in the region, providing the technology for its use can be developed.
Table 4.2 Agricultural and forest/woodland land use in Sub-Saharan Africa, 1989-1991
|Regions/countriesa||Land area ('000 ha.)||Cropland (%)||Permanent pasture (%)||Forest/ woodland (%)|
|Central African Rep.||62,298||3.2||4.8||57.5|
Sources: Calculations of percenlages based on data from World Resources
284 285); FAO (1993).
a. Some island counlries included in table 4.1 have been omitted.
Although the more humid regions provide Sub-Saharan Africa's agricultural base and support most of its population, even they have been affected periodically by droughts that have brought severe livestock and crop losses, especially to the climatically marginal areas. Since the mid-1960s, Sub-Saharan Africa has been the major global region worst affected by drought, mainly in 1968-1971 in the Sahel, Ethiopia, the Sudan, and Somalia, in 1982-1985 in both the Sahel and southern Africa, and again in 1990.
Sub-Saharan Africa has about 10 per cent of the world's annual internal renewable water resources for 18 per cent of the world land area and about 10 per cent of the world population. Estimates for Africa as a whole suggest that 6,140 m3 per capita was available in 1992, of which 245 (4 per cent) was withdrawn, mainly for agriculture (World Resources Institute 1994: 346). However, data are provided by only 17 Sub-Saharan countries and the rest have to be estimated from other related information. Some countries are mainly riparian users of water from external sources over which they have little or no control and for which they compete. Only 45 per cent of Sub-Saharan Africa's population has access to safe water (UNDP 1994: 133) - the worst figures are for the Central African Republic (12 per cent), Uganda (15 per cent), and Congo (21 per cent). The prospects of increased water scarcity are considerable, given the evidence of poorer precipitation in the past three decades and the reduction in volume of several water bodies, associated with some evidence of worsening vegetation conditions or "desertification."
Sub-Saharan Africa has substantial mineral fuel resources, including oil, coal, and uranium. Nigeria is the biggest oil producer and exporter, with about 27 per cent of production in 1991. South Africa has over 90 per cent of the coal production and reserves and two-thirds of the recoverable uranium. There are also extensive renewable resources, including fuelwood and hydroelectric power. Locally, fuelwood is often the cheapest form of heat for cooking and readily available for the dispersed rural population. Where market and supply systems are well developed, kerosene can now be cheaper, apart from the capital cost of buying an oil stove. Hydropower is the greatest most readily available renewable energy resource, but, apart from very small schemes, can involve considerable capital costs, force the resettlement of rural communities, and cause the loss of agricultural land. It is not very economic for the supply of power to a largely dispersed rural population. Greatest hydro-power potential is in Zaire and Zambia, which also have the greatest installed capacity.
The biggest producer and consumer of energy in Sub-Saharan Africa is South Africa, which is the richest in developed commercial energy resources. Gabon, Zimbabwe, and Botswana come next. Some countries, such as Zambia and Kenya, saw a steep decline in energy use in the 1980s owing to rising fuel costs and falling demand.
Natural vegetation and deforestation
The extent of forest and woodland in tropical Africa is difficult to estimate owing to differences in classification and measurement techniques. The estimates for 1990 published by the Food and Agriculture Organization (FAO 1993) and the World Resources Institute (1994: 308) suggest that of the forested area of tropical Africa, including the tropical islands, 47.6 per cent is moist deciduous forest (mainly moist savanna woodland with 1,000-2,000 mm annual rainfall), 16.4 per cent is rain forest, with over 2,OOO mm, and 17.5 per cent is dry deciduous, with 500-1,000 mm. The rest (18.5 per cent) is very dry deciduous and desert, with less than 500 mm, and hill and montane forest (500 mm with about a three-month rainy season is marginal for tropical agriculture dependent on rainfall). More or less 80 per cent of the forest and woodland area, occupying rather less than a quarter of the area of Sub-Saharan Africa, is moist enough and with large enough trees to be threatened by agricultural clearance (subject to soil limitations), logging, and fuelwood cutting, apart from protected areas occupying less than 5 per cent of the Sub-Saharan land area.
Tropical rain forest, savanna woodlands, and subtropical forests are being depleted in Sub-Saharan Africa at a rate that many observers find alarming. The highest subregional rate of deforestation (percentage annual reduction) estimated for 1981-1990 was for western Africa at 1.0 and the lowest was for central Africa at 0.5 (World Resources Institute 1994: 308, using the WRI regional classification).
Other primary resources
In minerals, Sub-Saharan Africa provides one of the world's greatest resources in both production and potential. Southern Africa is a particularly rich metalliferous zone, with gold, diamonds, iron, nickel, lead, chromium, vanadium, and manganese, but central Africa is one of the world's greatest sources of copper and cobalt and western Africa of bauxite and iron. Mining has played a major role in developing African economies and, including the production of mineral fuels, has provided the chief basic financial resource for the richest African economies. It has attracted large numbers of migrant labourers and has produced the largest concentrations of urban and industrial population in Sub-Saharan Africa.
Wildlife resources are more important in Africa than in any other comparable global region. Apart from experiments in farming wildlife, aimed at a higher production of meat per unit area than from conventional livestock, wild animals are a valuable genetic resource and one of the most important elements in African tourism, especially in eastern Africa.
There is widespread agreement that a country's most important resource is its people. Simon (1981) called people the ultimate resource, requiring improved education, health care, and nutrition. Population growth can thus be regarded as an asset to development, depending nevertheless on its rate in relation to the rate of production growth.
Sub-Saharan Africa had the lowest percentages amongst the major global regions of the appropriate age group enrolled in primary, secondary, and tertiary education in 1990 and 1991 (UNDP 1994: 156159; World Bank 1994: 216-219). Primary enrolments are particularly low in Ethiopia, the Niger, Burkina Faso, Mali, and Guinea. Senegal, Mauritania, the Sudan, and Sierra Leone are also below the SubSaharan average, i.e. there is a marked concentration of low levels of primary education enrolment in the part-Sahelien countries for a variety of reasons, including problems of accessibility and warfare (Chad is an exception, with only just below-average enrolment). Most Sub-Saharan countries show a sex differential in favour of males, but the difference has in most cases been considerably reduced over the past two decades.
In health care, too, Sub-Saharan Africa had the worst ratios of population per doctor or per physician in 1990 ("doctor," the term used by the United Nations Development Programme, is evidently much broader than "physician," as used by the World Bank: UNDP 1994: 150-153; World Bank 1994: 214-215). Infant mortality and under-5 mortality rates were also the worst, and several African countries had high rates of malnutrition amongst children under 5 for 1987-1992, although the worst figures recorded were in India and Bangladesh. The data suggest that health-care problems are particularly severe in Burkina Faso, Malawi, Rwanda, the Niger, and Ethiopia.
Women are arguably the most wasted human resource in SubSaharan Africa. Their access to credit, technology, and production resources in agriculture - especially land - is constrained by social and legal barriers. With certain exceptions, notably the trading women of southern Nigeria and Ghana, their earning capacity is much poorer than that of men, and most women spend their lives chiefly in rearing children, household maintenance, headloading water and fuelwood, pounding grain, and cultivating certain crops, usually of lower value - the "women's crops." They are mostly less educated than men and less well nourished, although the proportion of educated women has improved in the past two decades.
Tables 4.1 and 4.2 suggest that population growth may well be a threat to land-carrying capacity in several of the Sub-Saharan countries. As the population totals have increased (and even rural populations have increased, despite urbanward migration and expansion of the agricultural area), so landholdings have tended to decrease in size and the fallow area, still important for restoring fertility, has been reduced.
Dependence on agriculture will involve greater pressures and a more precarious food situation in future, possibly entailing greater dependence on food imports and food aid, combined with more intensive production using improved agricultural technology and innovations. Much of the agricultural base is widely dispersed, with long distances to market and high transport costs plus poor market information. Imported food is more centrally marketed, often cheaper than locally produced food for the urban consumer, and easier to subsidize in order to support the poor or keep down urban wages. In some cases food imports are not the effect of low agricultural productivity but, at least in part, the cause.
In Sub-Saharan Africa one can contrast the poorest countries such as Ethiopia, where high population growth and poor productivity mean that people have to struggle even to provide basic needs, with more productive countries such as Kenya, where high population growth constrains the development effort. Population growth is not the cause, even the main cause, of poverty and decline in Sub-Saharan Africa, but it does mean that high rates of growth in productivity must be achieved in order for the economy to do more than stand still. The World Bank argues that economies need to grow by at least 4-5 per cent a year. The target for agricultural production should be 4 per cent to meet food requirements and generate the foreign exchange needed for development, and for industrial production 5-8 per cent, with a rapid expansion of jobs to reduce unemployment (World Bank 1989: 4).
Unfortunately, the World Bank devoted all too little space in its 1989 study of Sub-Saharan Africa to the implications for, and the costs of sustaining, the natural environmental base, although in looking at the case for increasing agricultural production it did point out that agricultural expansion cannot be adequate to meet needs without adverse environmental consequences and that there was a need to reverse "the degradation of natural resources that threatens long-term production" (World Bank 1989: 8-9, 89-91, 100-103). However, more recently the Bank has shown increasing environmental concern by proposing to assist in national environmental assessments (see below). In 1991 the Bank set up the Global Environmental Facility to invest in green projects of global importance by paying for research and for the incremental cost of protecting the environment above that which is in the interests of the developing countries themselves (Reed 1993; World Resources Institute 1994: 229-231). Although clearly an advance in Bank policy, nevertheless the Facility has met with criticism for its financial limitations.
It is becoming increasingly difficult in Sub-Saharan Africa to provide adequate educational and health facilities as productivity falls or remains stagnant and the need to repair or improve deteriorating and inadequate infrastructures grows. In almost all the Sub-Saharan countries, structural adjustment and stabilization programmes, mostly advised or managed by the World Bank and the International Monetary Fund, have become necessary in attempts to cope with enormous international debt and debt service payments, to deal with external trade deficiencies, and to resolve internal debt problems, overspending, fiscal imbalances, inflation, and productive decline. In many cases these programmes have led to a worsening of the more adverse social effects, including reduced availability of health services and education as rising costs have forced up charges.
On the basis of gross national product, the World Bank classifies 27 Sub-Saharan countries as low-income economies, 5 as middleincome, and 4 as upper-middle-income. Low income per capita leaves little room for savings and investment or for the finance required to support an adequate infrastructure and services. The United Nations Development Programme employs a "Human Development Index" (HDI), from which Sub-Saharan Africa's situation emerges just as bleakly (UNDP 1994: 130-131). In 1992 only six Sub-Saharan countries had HDIs over 0.5 and two of these were island groups; the mainland countries, in descending order of HDI, were Botswana, South Africa, Gabon, and Swaziland. Outside southern Africa only small, mineral-rich Gabon showed any promise.
Sub-Saharan Africa also has low and declining levels of foreign investment, partly because of doubts about future political stability, despite the spread of greater democracy, and some evidence of capital flight. External factors, such as the demise of communism in Central and Eastern Europe and the former USSR and the economic boom in East and South-East Asia, have encouraged major investment flows to poorer countries to go elsewhere. However, more aid flows into Sub-Saharan Africa than into any other major global region - more than one-third of the official development assistance to the less developed countries in 1991. In nine Sub-Saharan countries it provided more than one-fifth of the gross national product (World Bank 1994: 19B-199). It has been argued that the Sub-Saharan countries will need a greater measure of self-reliance in the face of falling terms of trade, mounting debt, and low levels of investment (Ikoku 1980). Greater self-reliance, with the implication of more independent policies and greater self-sufficiency, may well be necessary in some of the Sub-Saharan countries, but such a policy should not neglect comparative advantage in production and trade or the need to build a more productive export industry to fund the new inputs needed for development.
Clearly the sustained use of natural resources is likely to be increasingly difficult in the face of the economic and social pressures listed and the natural inclination of poor people and poor countries to seek short-term solutions to their problems, which at least offer immediate survival, combined where possible with rapid growth, even at the cost of some environmental damage. For the poor, growth has been claimed to be not an option but an imperative (Husain 1994: 163). In part some of the "short termism" implicit in structural adjustment policies may have encouraged environmental degradation by quick "solutions," coupled with considerable pressure to raise export performance and increase local food production, although some environmental degradation has a long history, often linked to institutional distortions (Husain 1994: 163). Currently it is not so much increasing productivity that is the problem but the speed with which it has to be undertaken to offset rapid decline and rapidly increasing population. Incentives are needed for improved resource use, but these are affected by both price-related and institutional factors.
One of the most hopeful signs has been the introduction of National Environmental Action Plans (NEAPs) incorporating a holistic approach. These were in effect suggested in 1987 in an offer by the president of the World Bank of the Bank's assistance in nationwide environmental assessments. They were pioneered in Madagascar, Lesotho, and Mauritius. Other countries engaged in similar national environmental planning include Ghana, Burkina Faso, Rwanda, and the Seychelles (Falloux and Talbot 1993). There are some external resources to support NEAPs, but they are limited. Many of the developed countries were reluctant to sign the Biodiversity Treaty at the Earth Summit in Rio de Janeiro and some never signed it. Undoubtedly this was discouraging to the developing countries, most of which have been left to provide a large part of the funding required by their environmental management programmes. Yet without such funding and management, limited as it is at present, growth can hardly be sustained without undermining the environmental basis. Probably more commercial considerations will have to be taken into account in future conservation initiatives, or the costs of conservation will be seen as an immediate drain on very limited and even decreasing resources, despite the essential long-term advantages (Moyo, O'Keefe, and Sill 1993: 4).
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