Population, Agricultural Productivity and Environmental Degradation in Africa:

The cases of Rwanda and Zaire

by Jared Miller

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In some parts of Africa, increased agricultural production degrades the health of the environment. Although agricultural production and environmental quality are related in the long-run, the short-term effects of population pressure have separated the two temporarily; the costs of increased agricultural production, in terms of environmental degradation, have been postponed for future generations. Through extensification(the expansion of cropland) and intensification(the increase of farming on existing cropland), the current demand for food has been met by jeopardizing the future supply. This paper examines the context of the discourse surrounding the environmental degradation/population growth nexus, considers the general environmental effects of population growth, and illustrates the complexity of the issue in the cases of Zaire(Now the Democratic Republic of Congo) and Rwanda.

Although this paper states that population growth creates problems of long-term environmental degradation in Africa, other interpretations infer that population growth could increase environmental health. Rosenzweig et al., summarizes this opposing interpretation, made by E. Boserup. According to this stance, increased agricultural production boosts agricultural yields and promotes salubrious stewardship of land because:

1) It [increased agricultural productivity] reduces fallow periods 2) it increases investment in land; 3) it encourages the shift from hand-hoe cultivation to animal traction; 4) it encourages soil fertility maintenance via manuring; 5) it reduces the average cost of infrastructure; 6) it permits more specialization in production activities; 7) it induces a change from general to specific land rights; and 8) it reduces the per capita availability of common property resources(forest, bush, and/or grass fallows; communal pastures). (Rosenzweig et al., 1988 in Shapiro, 223)

In the context of Africa, her statements are still pertinent, yet flawed because they only address one time period in the population growth/environmental degradation relationship. Land extensification and agricultural intensification imply environmental problems that, if severe enough, will contradict Boserup’s statements in the long-run. In many circumstances, agricultural production is independent of the health of the environment in the short-run. There are numerous examples of how environmental degradation is caused by attempts to increase agricultural production. The following environmental implications of extended and intensified agriculture represent the most pressing environmental problems facing Rwanda and Zaire. Not surprisingly, many of these problems are occurring simultaneously and may be the cause and result of each other.

Deforestation

In Africa, the types of deforestation are regionally specific, but the consequences are universally severe. Geores and Bilsborrow(1991) outline the two principal types of deforestation important to the cases of Zaire and Rwanda: extension of agriculture onto marginal lands and the conversion of forests to fields(Shapiro, 225). Regardless of the category, deforestation almost exclusively takes place on lands of lower agricultural value. Furthermore, the act of deforesting destroys the natural habitat of flora and fauna, increasing scarcity of meat and fuel wood. Without proximate sources of fuel wood, agricultural workers have to travel farther to gather it and have less time to tend to the new fields(Shapiro, 225). Lastly, large-scale deforestation decreases productivity of cropland because it greatly accelerates erosion and the leaching of minerals. Today in Zaire and Rwanda, erosion is the scar of deforestation on the African landscape.

Shortening of Fallow Periods

Besides the harmful effects of deforestation, the shortening of fallow periods poses another threat to the natural environment. In both Rwanda and Zaire, fields that lay fallow for shorter periods of time suffer from reduced regeneration of minerals and decreased soil fertility. Not surprisingly, yields from the same lands will fall steeply over time if land is not allowed specific periods of rejuvenation(Shapiro, 232).

The shortened fallow period implies two related problems – growing demands on labor and crop specialization. Primarily, accelerated use of arable land in response to population pressure will result in less maintenance, such as weeding, and will deteriorate soil quality. Furthermore, the reaction to diminished soil quality is a change to monoculture. As overworked soils can support fewer types of crops, Cassava has become more prevalent because of its capacity to grow in deficient soils. However, Cassava may not be as nutritionally sound as other types of staple foods(Shapiro, 232). In summary, shortened fallow periods represent a generally available way to increase agricultural yields although the repercussions are already being felt.

Agricultural Technology

Boserup assumes that population growth will result in enhanced stewardship of scarce lands through technological innovation and manuring. In Africa, general manuring is not feasible because of the exorbitant cost of fertilizer for agricultural workers(May, 325). Indeed, many parts of tropical Sub-Saharan Africa do not have the requisite quality of soil humus to take advantage of such opportunities even if they were affordable(Shapiro, 224). Agricultural technologies, such as plows and tractors, are also prohibitively expensive and many areas lack the financial services that would make acquiring and implementing such technologies possible. However, even if agricultural technologies were made available, the cost of general maintenance may be more than many rural farmers can undertake(Shapiro, 226). So far, agricultural technologies have not answered the concern of population pressure in Rwanda and Zaire because most farmers do not have the money to pay for such innovations; yet, it is still unclear if existing arable land could even support such innovations.

Fragmentation of Land

Problems of intensification often stem from traditional rules about the division of agricultural lands. In some parts of Africa, Rwanda in particular, land is awarded through generational gifts(May, 326). Not surprisingly, each subdivided plot on familial land is worked harder to support a growing demand for food as fixed lands have to provide for growing populations. While intensification of agriculture is the direct effect of land division, extensification may be the indirect effect. For example, decreasing marginal returns due to over-cultivation may motivate rural workers to expand cultivated areas. Local population stress can encourage movements across space through the conversion of forests, mountainsides and savanna to cropland(May, 326 and 327).

Population Pressure and the Environment: the cases of Zaire and Rwanda

Both Zaire and Rwanda recognize the pressure of growing populations on their fixed territories. To date, food supply has almost always kept pace with demand for food. However, the cases of Rwanda and Zaire show that political policies and the demographic character of certain areas dictate the relationship population growth and the environment.

Population and the Environment: Rwanda

Rwanda’s governmental population policies, in addition to its acute problems of overpopulation, define the relationship of population and the environment. Rwanda already has the highest population density in continental Sub-Saharan Africa. Furthermore, it grows by approximately 3.2% every year. The demand for land increases with population growth considering that 97% of the economically active population works in agriculture(May, 322). However, the stresses imparted upon Rwanda’s environment, dissimilar to the experiences in other countries, are compounded by governmental policies that increase the pressure on eroding lands.

May describes the two distinct thrusts of Rwandan population policy as "adapting to the effects of policy growth" and "decreasing the population growth itself(328)." To adapt to population growth, the Rwandan government has attempted to increase both emigration to neighboring countries and agricultural production. To decrease population growth the policy makers created a national family planning initiative and, more recently and less successfully, a policy aimed at broadly integrating national population programs to decrease fertility. However, both programs have contributed to the population problem.

Although the results of the emigration plan are unclear, increasing food production through extensification and intensification has had the broadest impact of the "adaptive" policies. Such policies, starting in the 1960’s, encouraged extensification and intensification and wrought havoc on Rwanda’s natural environment. Furthermore, Clay and Johnson, suggest that governmental interference may have compounded the problem by actually encouraging higher fertility levels. As evidence, they identify a direct relationship between farm size in Rwanda and fertility rates(Clay and Johnson in May, 329). The Rwandan government’s attempt to provide food security for its citizens resulted in the deterioration of existing lands and increased population growth rates. Above all other policies, the "adaptive" policies have shaped the character of Rwanda’s environmental conundrum.

To decrease population growth, the Rwandan government wisely launched a population program in 1981 and a national population policy in 1990. However, their late implementation has reduced their potential for success. The first policy has been somewhat successful in reducing population growth; contraceptive use has increased and total fertility rates have decreased to 6.2 children per woman(May, 330). The second policy primarily aimed to reduce the propensity for early marriage. As of 1995, the second program had not brought "tangible results(May, 330)."

On the whole, Rwandan policy makers have aggravated the problems they were attempting to solve in their "adaptive" policies. On the other hand, the results of their commitment to decrease population growth have been moderately successful, but have not succeeded in bringing population growth down to more manageable levels. As a result, the decaying natural environment will undergo more severe degradation and its capacity to feed the population will be reduced if sustainable and inexpensive agricultural technologies, or food imports, do not arrive in the coming years.

Population and the Environment: Zaire

Unlike Rwanda, Zaire’s urban character is the principal source of environmental degradation. More specifically, rapidly increasing population growth in the cities – 80% of Zaire’s total population growth – has made demand for food independent of supply(Shapiro, 228). The consumers are not involved in agriculture and are thus forced to rely on domestic food supply from rural areas or international food imports. The demands placed on rural areas by the urban population of Zaire, causes environmental decay that, although ignorable in the short-term, will likely have serious repercussions in the future.

Like in Rwanda, population growth in Zaire is based upon a tenuous situation of agricultural intensification and extensification that, to date, has managed to keep the general populations fed. The price has been enormous however; only Brazil and Sudan lost more open forest in the 1980’s(Bilsborrow, 1992 in Shapiro, 231). As tropical forest quickly loses nutrients, the postponed consequences will most likely have an impact on prices and scarcity of foods in the near future(Shapiro, 232).

Similar to the situation in Rwanda, intensification efforts have simultaneously been seen as another solution to problems of food availability for the growing populations. Areas with access to markets have seen the most significant drop in fallow periods. Today in Zaire, fallow periods are merely ¼ to ½ of the required period for full soil regeneration(Shapiro, 230).

The supply of food from rural areas for the cities will most likely diminish in the future. Because of the urban character of Zaire’s demography, urban population growth is independent of environmental quality of rural lands. Until food prices increase, there will be no economic incentive for reduced fertility. There need to be more creative and sustainable ways to harvest on eroded soils to keep pace with Zaire’s population. If new agricultural technologies do not arrive, the urban centers will face food crises. Of course, Zaire also needs policies that focus on reducing the demand for food – strategies to decrease population pressure.

In conclusion, the threat to the environment posed by population growth is a vicious cycle. The effects of land degradation, in terms of extensification and intensification, are both the cause and result of attempts to increase agricultural production. Specifically, the problems emerge because of the dichotomy separating food supply and demand in the short-run. Primarily, artificial and unsustainable equilibriums of supply and demand are caused by the time lag between increased agricultural production and environmental degradation. Rwanda faces an especially problematic future because of its flawed reaction to population pressures. On the other hand, Zaire’s population pressures are compounded by the explosive growth of an urban population in disregard for domestic agricultural production capacity in the long-run. Unless new sustainable agricultural practices are instituted soon, or unless population pressure decreases, Zaire and Rwanda may face severe food security problems in the future.

References

Shapiro, David. 1995. "Population Growth, Changing Agricultural Practices, and Environmental Degradation in Zaire. " Population and Environment. v16:no3.