Desertification Research Paper

1.1 History And Definitions

The ‘Agenda 21’ document of the 1992 United Nations Conference on Environment and Development (UNCED) defined desertification as ‘land degradation in arid, semi-arid, and dry, subhumid areas resulting from various factors, including climatic variations and human activities.’ The processes of degradation were said to be soil erosion, nutrient depletion, crust formation, salinization, reduction in pasture and agricultural productivity, loss of biodiversity, and reduction in vegetation cover in susceptible drylands. Of course, uncertainties abound, the circumstances fostering reversible or irreversible change, the resiliency of different semi-arid environments, the different roles of natural and anthropogenic driving forces, and the synergies among these elements.

Scientists were exercised as early as the 1920s with the ‘the advance and spread of the desert’ in Africa. It was then that France began the first studies of the process in West Africa, finding evidence of mobile sand dunes, human fossil remains in now-dry areas, and declining annual rainfall. It was concluded that the Sahara had grown, and was still growing, owing to poor land management, which had worsened under the colonial regime.

These early judgments preceded what environmental historians are now discovering to have been a much more traumatic event, the American ‘Dust Bowl’ of the 1930s. Sears’ Deserts on the March (1949) evoked accusations of widespread anthropogenic degradation. He, and others, believed they had evidence of widespread environmental degradation in the drylands of the Old World, whose cause, as in the mid-western states, was also thought to be mismanagement. With these narratives very much in mind, E. P. Stebbing, a forester, identified the causes of degradation in British West Africa to be shortened agricultural fallow periods, shifting agriculture, and overgrazing (Stebbing 1935). An Anglo–French Forestry Commission toured the Niger–Nigeria border in 1936–7, and their conclusions were far more circumspect. They saw degradation as place-specific and treatable. Yet a member of this Commission, the influential French botanist Auguste Aubreville, held to the ‘desert advance’ hypothesis, and first used the term ‘desertification’ in 1949 (Warren 1996).

In dryland Africa, severe drought and famine in the 1970s, following decades of good rainfall, again revived the desertification debate, with depressing reports of desert advance appearing in scientific publications and the media. This alarm stoked the United Nations Conference on Desertification (UNCOD), held in Nairobi in 1977. UNCOD, and the National Plans of Action agreed to at that meeting, still viewed people as the main agents of desertification.

1.2 Current Research

Research into the links between climate, management and degradation has taught us a great deal since the 1970s. Since then, many detailed studies of human— environment interactions on the local scale have been carried out in the drylands, spurred on by advances in climatology, soil science, botany, geoinformatics, agronomy, and the social sciences.

This research, conducted by numerous scholars from the natural and social sciences, offers a longer-term view of what happens as rainfall fluctuates, or when soils are lost and gained. More generally it has examined the complexity of the linkage between resources and people in the drylands, and the role of adaptive local resource management. Above all, it is now possible to challenge notions about an equilibrium state or ‘carrying capacity’ in these environments and from there to challenge the desertification narrative with better, if still imperfect evidence. Yet laying the desertification discourse to rest is difficult. At least six themes remain essential elements of the desertification debate.

1.2.1 Advance Of Desert. Large-scale Saharan expansion has not been proven within the period of the historical record. Desert advance in the Sudan has been asserted since the 1930s, but Hellden (1991) found no such evidence from satellite imagery, settlement histories, sand movements, and degradation conditions around boreholes. The current view is that the Sahara expands and contracts periodically as rainfall varies. Desert advance (as in the severe drought of 1984), and localized degradation, is usually short-term (Tucker et al. 1991, Nicholson et al. 1998).

1.2.2 Resilience Of Dryland Ecosystems And Land-Use Systems. Degradation is, therefore, usually localized and ephemeral, largely a function of the complexity of relationships that exist between humans and natural systems. Semi-arid ecosystems, far from being fragile, exist in a range of semi-permanent ‘states’ dictated by disturbance, drought, fire or insect attack; they are well adapted to these forces. Similarly many indigenous management systems redistribute nutrients, plants, grazing pressure and water to create ‘enriched’ patches in the landscape.

1.2.3 Influence Of Grazing And Livestock. The UNEP Atlas of Desertification (1992) asserted that 58 percent of soil erosion in dryland Africa was the result of overgrazing by livestock, lending support to Garret Hardin’s ‘tragedy of the commons’ hypothesis. Such figures gave way to more conservative estimates in the latest version of this Atlas (Middleton and Thomas, 1997). There is now greater confidence about the heterogeneity and patch dynamics of pastoralist grazing strategies so critical to many drylands. Less vegetation is not necessarily worse vegetation. It is difficult to overgraze in a dynamic nonequilibrium system, dominated by annual grasses, where the external forces such as drought are more powerful than the internal ones such as animal numbers.

1.2.4 Effects Of Increased Population In Rainfed, Dryland Agricultural Systems. No necessary Malthusian link exists between elevated population levels and resource degradation. Indeed, because there is often an incentive for rural people to invest in anti-degradation measures in these circumstances, more people (and labor) may mean less erosion, and the initiation of compensatory risk management strategies.

1.2.5 Soil Erosion And Fertility Decline. Although topsoil erosion does occur in drylands and soil is blown or washed away, these processes do not themselves necessarily result in degraded landscapes. Soils are often replaceable or may be very deep, and can accumulate down-slope or down-wind where they may be more valuable to local people. Indigenous dryland soil conservation systems are impressive. Yet even after decades of research, soil erosion and the values placed upon it by society are very difficult to measure.

1.2.6 Climate Change. There are two issues here. Charney and Stone (1975) suggested that devegetation might induce regional drought—bare soils are cooler because they reflect more solar energy and cool surfaces discourage rainfall. This hypothesis remains disputed. Current research provides strong evidence that changes in surface characteristics, including vegetation, affect local and regional rainfall patterns significantly. Some climatologists however, find little evidence in this claim as registered in the coarser scale climate record (Williams and Balling, 1996). In addition, potential global warming and the El Nino-Southern Oscillation will have differential, and as yet uncertain effects on certain drylands, with the majority of current models suggesting increased rainfall and temperature variability in Africa.

2. Desertification Policies

Research, policymaking and interventions are strongly linked. For example, when scientists pinpointed advancing deserts, the policy response, was ‘plant green belts’! Roosevelt commissioned a study of a massive belt between Texas and North Dakota after the Dust Bowl. Stebbing (1935) recommended much the same for Africa, and UNCOD proposed a circum-Sahara green belt. The Algerian Government actually began planting trees, employing conscripts to do so. Where scientists believed that herdsmen or farmers were irrationally causing degradation, policy-makers and government officials prohibited goats, tree cutting or grass burning, and destocked herds, or, on a much more massive scale, they enforced soil conservation programs.

Antidesertification measures have been international in scope. A suite of international institutions materialized after the great Sahelian drought of the late 1960s and early 1970s. First, the UN SudanoSahelian Office (UNSO) was charged with combating drought, later taking on desertification issues. It was later joined by the UN Environment Programme and the FAO (Food and Agricultural Organisation) in these roles. Scientific panels and advisors produced a ‘veritable sandstorm of literature’ (Mortimore 1998) on the complexities of drylands. In general, the prognosis was gloomy: 10 percent of the earth’s surface was human-made desert; and the process would continue. Desertification became enshrined in international policy.

African states absorbed some of UNCOD’s recommendations from the late 1970s, although they were held back by poor funding. Projects were initiated, most designed to arrest soil erosion. Some were implemented without adequate local consultation or participation. Many, like the GERES project in Burkina Faso where bulldozers were used to create earthen bunds across many slopes, actually increased erosion rates. Fuelwood supply projects and the drastic destocking of indigenous pastures failed for the lack of local complicity.

Unforeseen ramifications followed in the post-UNCOD, post-Sahelian drought era. In Niger, proposals for green belts resorted to authoritarian measures for implementation, for in local eyes, as in the eyes of scientists today, they were deeply irrational. In similar vein the military rulers of Mali banned burning, counter to local know-how about the enriching powers of fire on pastures. In many countries, the cutting of fuel-wood was unnecessarily proscribed. Most disturbingly, the characterization of African pastures as ‘overgrazed’ came to infest writing about them. At- tempts were thus made to reduce the numbers of livestock, to privatize grazing lands, and even to replace herding the commons with systems based on European and North American models (Warren 1996). The desertification threat was used to justify authoritarian control over natural resources and land-use practices.

A broadened, perhaps softened conception of desertification suggests a new range of policies that, given sensitive application, may prove more successful because they are more trusting of dryland populations and more aware of ecological diversity. New initiatives are based on a better understanding of the three main issues in dryland management: drought, desiccation and degradation. Drought is common currency among dryland folk. It may not be welcome, but people clearly have a portfolio of coping strategies to deal with it, and reflexive management that constantly adapts to an ever-changing situation. These indigenous systems are now being supported, rather than replaced or obstructed. Desiccation is known to have been frequent in the history of human occupation of drylands. Large-scale shifts in livelihood practices occur under progressive aridity, but Sahelian drought illustrates that relief, restocking and resettlement are necessary when this happens. Degradation requires a range of responses. Rich repertoires of conserving indigenous techniques exist, some—like permeable contour bunds—already improved through hybrid experimentation between farmers and scientists. Drylands and dryland peoples and their economies are heterogeneous. Policies increasingly aim to protect this diversity, rather than erase it. Greater clarity of land tenure security is needed, and rangeland areas require special forms of collective management. In brief, livelihood security is essential to good conservation.

3. The Convention To Combat Desertification

UNCED, held in Rio in 1992, breathed new life into the moribund desertification concept. Fortunately, Chapter 12 of UNCED’s Agenda 21 document is far less alarmist in its tone than UNCOD’s recommendations of 15 years earlier, adopting some of the findings and views of the new research reported above. For example, climate change is now seen as a major contributor to desertification, and drought preparedness, education, and strong local participation are now stressed.

The CCD came into force on December 26, 1996. Although there was skepticism about this new international effort, nongovernment organizations and other actors from developing countries had a relatively strong involvement in drawing up the Convention. The various CCD components are legally binding on the parties, and include annexes for Africa, Asia, Latin America, the Caribbean, and the northern Mediterranean. Almost 160 countries had ratified the Convention by September 1999. The focus has moved to implementation, despite significant questions about who pays, coordinates, and monitors the activities. By late-1999 National Action Plans were drawn up by most dryland nations, but progress is hampered since there is no international CCD implementation fund available.

4. Conclusion

In the absence of well-adapted technologies, life in drylands is harsh. That degradation of these lands follows from social and climatic processes is not in dispute. That degradation amounting to desertification of the magnitude assumed in the early debates, or even in the recent Convention, has been strongly challenged by the research and other communities. Nonetheless, desertification remains a powerful narrative that has captured the imagination of certain policy makers, governments, and scientists, and it has persisted with peaks and troughs of interest since the 1930s. Its power is problematic, since ‘the search for accuracy appears to be vulnerable to generalization, over-simplification and distortion for political or funding purposes’ (Mortimore 1998). Desertification has certainly served specific constituencies quite well, including national governments seeking to extend their control, international bureaucracies seeking legitimacy, and scientists seeking research funding.

Tackling the various processes that the term desertification subsumes is a major challenge, given that dryland populations suffer the impacts of droughts and desiccation, and need to exploit land, water, and timber resources in ways which often result in degradation. As an explanatory term, however, desertification has been used too broadly and too loosely, and this has been counterproductive.

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