The theory of degradation

In the preceding three chapters I have located the primary source of the instability (disequilibrium) of dryland environments in the variability of the rainfall, and followed the implications of this instability (or disequilibrium) into two areas: the management of the rangelands for grazing livestock; and the management of cropping and technological systems by farmers. I have suggested that containing and insuring against such risk must be among the primary objectives of all dryland households; furthermore, that other sources of risk originating in the economy may amplify its impact. Since most dryland households (though not all) are primarily dependent on the use of natural resources, it follows that risk management must form a necessary part of their strategy.

Much of the debate about the degradation of natural resources in dryland environments ignores this fact. This, I suggest, is because the theoretical assumptions that underlie statements about degradation are not those of instability but of stability, not those of disequilibrium, but of equilibrium as being the natural order of things.

As stated by Holling (1973: 17), the difference between stability and instability is as follows:

The title of this book is intended to communicate hope, which is the spiritual diet of farmers, and for none so much as those who live in the drylands. Smallholders are themselves like roots in the soil. They shoot in good times, but when times are hard, they search deeper (or wider) for the moisture and the nutrients they need to sustain themselves. They die back to the basics, and surprise us with their resilience when the rain returns. Small farmers and livestock producers are the roots of African economies, and the basis for their development.

For too long it has been the convention either to dismiss smallholders as anachronistic survivors, certain to disappear in the rush to modernisation, or as quite malignant in their treatment of the African environment. This condescension, as is now recognised, was more a product of ignorance than any rational understanding. Only now, when so many foreign transplants have wilted or died in the hard earth of Africa, is the value of indigenous resources openly acknowledged. Given an enabling policy environment and unobstructed access to new ideas or markets, the resources of dryland communities can be mobilised in sustainable systems for managing natural resources.

The evidence for these assertions is found in a heterogeneous corpus of fieldbased studies whose published reports are widely distributed.

Farming, like pastoralism, has suffered from negative stereotypes whose roots lie in colonial incomprehension of the ecological and economic constraints under which it must operate. Aubréville's caricature of agricultural land use in the savannas of West Africa (chapter 2) contains two of the main elements of the stereotype: first, shifting cultivation, with its partner in crime, bush-burning; and second overcultivation, exposing the soil to erosion by wind and water, thus depleting its nutrients. A third element was the practice of interplanting in crop mixtures, long thought to be inefficient in terms of labour use, technology and yields.

In this chapter the nature of risk in dryland farming is explored, in order to answer the question: can the concept of instability, or disequilibrium, be usefully applied to understanding semi-arid farming systems?

Rainfall variability

Rainfall variability – within seasons between seasons and over several years – plays as important a part in defining risk for the farmer as it does in managing the rangelands. The coefficient of variability of the rainfall tends to decrease as the average amount received each year increases. The regimes under which farmers operate are therefore subject to less extreme variability than those of the arid rangelands. However, it does not follow from this that the risk to their livelihoods is diminished, more especially as dryland farmers are not able to choose less risky environments in which to work.

The limitations of an equilibrial view of dryland ecosystems (chapter 4) are now recognised. The concept of instability, or disequilibrium, offers an alternative basis for understanding their short-term dynamics. What of long-term changes? As soon as we extend the timeframe of our analysis, it becomes apparent that many dryland ecosystems are in transition between one state and another, or always have been intransition, driven by climate change, the progressive development of soil formations, erosion cycles, and episodic natural events like volcanic eruptions, droughts and floods. Indeed, when the timeframe is lengthened, all ecosystems may be vulnerable to extreme or ‘surprise’ events, whether they emanate from outside or from within the system, as ‘accidents waiting to happen’ (Holling 1987).

For policy purposes, the timescale is important. Because of their frequency, extreme events in the drylands offer a challenging laboratory for working out an appropriate interface between technology and nature. Two main management modes are available (ibid.). The ‘technological–industrial’ mode seeks to control variability and reduce diversity – as in livestock ranching systems. It thereby increases the vulnerability of both ecosystems and production systems (unless financial institutions protect the latter). On the other hand, a ‘low technology’ mode of management – as used by indigenous dryland peoples – seeks to adapt to variability and to exploit diversity. It thereby strengthens the resilience of both the ecosystem and the production system.

The ‘crisis of sustainability’

In the previous chapter, it was argued that the crisis of sustainability is often represented in terms of negative feedback loops in an equilibrial system, disturbed by ‘external’ factors, such as the growth of the human (and livestock) populations, drought, or the market. For neo-classical economic analysts, population growth is uppermost; in socialist critiques, the market; while technical appraisals emphasise the role of rainfall and bioproductivity constraints. In this chapter, the hypotheses that population growth, rainfall variability and monetisation cause increased environmental degradation will be put to empirical test by means of a comparison of two farming systems in which these parameters vary.

Conservation has different meanings for different people. For some it implies the exclusion of humans from protected natural reserves, and for others, the protection of threatened species or habitats in ecosystems that are already occupied or exploited by human populations. The impracticability, as well as the controversial ethics, of giving human needs second place to those of ‘nature’, has suggested to some writers the need for a multi-purpose strategy which not merely reconciles the sometimes contradictory demands of humans and nature conservation, but goes further to integrate the economic and conservationary management of the same habitats. In urbanised and industrialised Europe, such ideas have far-reaching implications (Adams 1996).

In dryland Africa, conservation thinking has two tributary traditions. The first is the demand, emanating from conservation lobbies in northern countries and tourism ministries of African governments, for protected reserves – protected, that is, from Africans. The drylands contain most of Africa's best known tourist game parks, and tourism is a major earner of foreign exchange in several national economies. The second is the soil conservation movement, which, having its historical roots in the USA in the 1920s and 1930s, became influential in colonial governments in the 1940s and 1950s (Anderson 1984; Huxley 1937; Stocking 1996). The thrust of soil conservation propaganda, particularly in its early years, was that African smallholders were recklessly destroying their natural resources by inappropriate land use practices.