Grainger (1990) likens the role of climate to that of a catalyst in a chemical reaction. Thus drought creates the conditions whereby human impact on the land increases, and the capacity of the land to tolerate it decreases. In this instance, drought is the indirect cause, whilst poor land use is the direct cause. However, poor land use can also be the result of poverty, ignorance, greed, or socio-economic change. So whilst natural and man-made factors catalyse each other, similarly social change, upset, or an unjust market system can exacerbate the problem. Of major concern, is the role of desertification in famine. Conventional wisdom states that desertification does directly lead to famine.
Mortimore (1987) believes that endemic societies have developed forms of insurance to reduce the risk of famine, which cope adequately on the whole, but which have been steadily eroded by societal and economic changes. Olsson (1993) believes that the link between famine and desertification is weak, being superseded by a greater importance played by the malfunctioning Sahelian market system and unjust credit and shiel systems. Thus a severe rainfall deficit of 1984 triggered speculation in food, which pushed prices out of the reach of rural budgets. Mortimore (1987) recognises the harsh role played by economics during such times. At the village level, the price of grain is as exogenous as the rainfall, and the mechanisms of its variability as impossible to control . Thus where food was available nationally, the rural dwellers couldn t afford it, and the internal redistributive mechanisms were poor. Such an idea alludes to Sen s notion of inadequate entitlements to resources
A brief, final note of controversy is that of the permanence of damage to drylands. Earlier commentators such as Stebbing believed in the complete irreversibility of land which had been lost to the desert. Much trouble in the present day, stems from our inability to show long-term impacts, that would confirm the time-scale over which desertification could be mediated. As both Hellden and Tucker et al noted from their studies of 10 to 30 years, such time-scales are insufficient to substantiate the desertification phenomenon. Olsson (1993) believes that we are ignorant to the inherent resilience of dryland ecosystems, which has been gravely underestimated . Therefore, what we may see as desertification, may be a temporary condition resulting from the annual climate variation. In many of the above examples, recovery of the ecosystem has not been long to follow dry years, emphasising this resilience. However, in the case of Oursi in northern Burkina Faso (Lindqvist + Tengberg, 1993), spatial discontinuities are shown between areas of recovery, and those without. Despite the increased rainfall (1985+), the lack of recovery suggests a deterioration of this ground resilience. Nevertheless, the high variability of productivity in time and space demonstrated by many other authors may still prove to mitigate the role of desertification.
It is evident that there is no issue within the framework of desertification that is free from controversy. An inadequacy of detailed, in-depth data and long-term observations continues to hamper the attribution and detection of causal factors in any greater detail than we have at present. The only way to eradicate these problems is to continue research and debate, and to this end, present controversy may be good for our understanding of desertification, as it forces us to examine aspects in greater detail. Without this increased knowledge, we are unable to substantiate either side of the debate; desertification reality or myth, human or physical? Accompanying the changing definitions, have been changing methodological approaches to the way in which such degradation might be managed. These seem to have changed from an environmental to a social point of view, alongside the growing recognition of the impacts of humans, and their social, political, and economic environment. However, even given an unambiguous definition, distinct causality and long-lasting effects, one is still left to ponder the different, and highly varying, temporal and spatial scales on which these factors operate.
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