Man is both the cause and the victim of desertification, a process which is continuing or even accelerating in Africa, Asia and Latin America – in fact, everywhere, except in the temperate croplands of Mediterranean Europe, North America and Australia.
Desertification is a dynamic process not necessarily exclusive of any particular region. Erosion, salinization, waterlogging, etc, can and do occur in different places and on different types of land. The areas prone to desertification are said to include 27 million hectares of irrigated farmland, 173 million hectares of rainfed cropland and a little over 3 billion hectares of rangeland. Desertification is therefore a threat for mankind as a whole in that it reduces the sustainable base of society at large. Right now, however, desertification is already a disaster for those populations directly affected, living in the most deprived areas of the world. They have lost their livelihood and suffered a sharp deterioration in their nutritional and health status. Whole communities have also been deprived of their economic activities; their social institutions have been disrupted and their most productive members have had to migrate and seek relocation elsewhere.
Because the term desertification sounds like a natural and localized phenomenon the public and many decision makers have tended to regard it as an inherently ecological and physical problem affecting desertified regions only, especially in Africa. There is always an image of wind-struck sand dunes, barren and hostile expanses uninhabited but for a few nomadic groups.
Arid lands and deserts are expressions frequently used as synonymous to designate certain areas , and drought is seen as an inseparable element. Yet areas affected by desertification are neither un-productive nor empty. Furthermore, arid areas are not doomed to desertification, which is a symptom- probably the most dramatic symptom – of the lack of development of particular parts of the world.
But what are arid lands? The expression refers to areas with a very dry climate, including steppes in temperate zones and pampas and savannas in tropical and sub-tropical regions. According to experts, arid lands cover around 35% of the world’s land surface. Deserts are areas with an extremely arid climate, very irregular precipitation and excessive evaporation. In these areas, organic life is restricted to a very meagre fauna and flora. Desertification has been used to describe the spread of desert surface and the reduction of the potential productivity of the affected areas. It implies a widespread deterioration of ecosystems and destruction of their biological productivity, ultimately resulting in the absence of perennial life.
Drought is seen by the lay person as a problem of water shortage due to insufficient rainfall for a certain period of time. The absence or shortage of rain and the temporary character of the problem are the most visible elements. However, the problem is apparently more complex. In theory, water shortage can be the result of weather or climatic change and, in fact, scientists are accepting that drought must be viewed as a recurring and periodic phenomenon, to be examined also from its economic and social perspective and therefore not only in terms of the levels of precipitation in a given place. So a distinction has frequently been made between meteorological drought, which refers to the rains failing to reach a certain level over a particular period of time in a given area, and agricultural drought which refers to the fact that the combined effects of amounts and distribution of rainfall, soil water reserves and evaporation bring about a drastic reduction of agricultural yields and livestock leading to food scarcity and other associated problems.
At the United Nations Conference on Desertification (UNCOD) in 1977, desertification was defined as ‘the diminution or destruction of the biological potential of the land, which leads ultimately to desert-like conditions and is an aspect of the widespread deterioration of ecosystems under the combined pressure of adverse and fluctuating climate and excessive exploitation’.
This deterioration process affects different types of land: irrigated rainfed land and rangelands. Irrigated land deterioration is reflected in the spread and increasing accumulation of salt in the soil, a phenomenon known as salinization, increasing saturation of the soil with sodium, a phenomenon called alkalinization, overpumping of aquifers, waterlogging and wasteful loss of water through evaporation. All these phenomena reinforce each other and lead to the reduction of the productive capacity of soil. In drylands the deterioration is manifested basically by the increasing erosion of land, the reduction of the vegetative cover and consequently of organic material, the insufficient fallow period and the slow spread of sand into the fields.
Finally, the degeneration of rangelands is reflected in the thinning of the herbaceous cover, the spread of bush and non-fodder vegetable species, the increasingly ephemeral nature of herbaceous resources and the lengthening of recuperation after the ‘normal’ drought season.
Desertification is a socio-economic and natural process which reduces the fertility and biological productivity of the soil to the level which characterizes deserts. It is one of the clearest results of the close and increasing inter-relationships between social and natural systems. Though desertification affects mainly arid and semi-arid areas, it is also found elsewhere. It is the result of a long historical process through which natural phenomena and human activities reinforce each other in changing the characteristics of natural environments. Throughout the history of mankind, arid and semi-arid regions have provided a habitat for large communities which have developed institutional mechanisms, life styles and socio-economic patterns according to the constraints and potentialities of surrounding natural system s. During recent decades, concern has been increasing because desertification has accelerated with dramatic consequences for mankind, and in particular, for the 230 million people directly affected. These are located mainly in developing countries, where the process worsens an already serious socio-economic situation. Governments are confronted with increasing difficulties in their response because of slow development.
There is a serious dilemma: if sufficient resources are not provided immediately to cope with the present dramatic situation, many people may starve to death. But if the structural causes of the problem are not dealt with today, more resources will be needed tomorrow to alleviate the plight of an even greater mass of deprived people and not just to cope with increasing environmental deterioration. What makes things worse is the magnitude of the humanitarian issues at stake. There is a need for urgent action, but the affected countries simply do not have the resources for that. Nor has the international community been able to find them or channel an appropriate amount to those most in need. The difficult questions are: how to deal with the present without jeopardizing the future, how to harmonize the palliative action of today with the preventive and corrective strategies aiming at the root causes and how to devise mutually supportive short and long-term policies. There are therefore humanitarian aspects both in the short and in the long term. The most obvious humanitarian aspects of desertification are related to lack of resources, regressive income distribution, increasing poverty, hunger and malnutrition, poor health, extinction of communities, disruption of traditional life-styles and economic patterns, migration, marginalization.
The short-term humanitarian aspects are very visible and motivate international action mainly in the form of aid, to alleviate the affected population. However, in the long term, desertification is affecting the very process of development, because it reduces the natural system’s carrying capacity. At the same time, environmental deterioration is a main cause of social and economic in security, resulting in greater vulnerability to both natural and man-made hazards. Social and economic security can be achieved only by long-term integral and sustainable development.
It has been said that desertification is a long-term physical and pervasive phenomenon caused by human action over the natural environment and in particular in arid and semi arid lands. According to some experts, even if past history shows that the role of man in desertification is minor compared to that of nature, there is no doubt that the acceleration of the trend over the past century, and especially over the past fifty years, is associated with the land-use practices and changes which followed the integration of the societies of arid and semi-arid regions in the international system.
The opinion that desertification is basically a natural phenomenon is sustained among others by a recent report prepared by Dr F. El- Baz and Dr T. A. Maxwell for NASA. But even this approach should be examined carefully. In fact, in their study of the Dar el Arba Desert, it is said that: ‘it should be abundantly clear that the role of man in desertification is minor compared to that of natural change. In fact, except for the sensitive fringe areas and the cases where ground water is being overexploited, his role is insignificant. But these are the only inhabited areas of deserts, so, from a provincial point of view, the result of man’s activities can be disastrous.’ The second part of this quotation is important to the extent that it supports the approach adopted in the present Report which views natural phenomena in relation to their human dimension.
The changes in production patterns and related land – use practices of dryland societies following their increasing integration into the international economic system are underlying causes of the acceleration of desertification. The acceleration is also triggered or exacerbated by changes in the dynamics of the natural environment and societies, and specifically by natural recurrent phenomena like drought and by changes in population dynamics.
Since all the causal factors are mutually inter-dependent, they reinforce one another and have a feedback effect which accelerates the whole process.
Traditional societies in arid and semi-arid lands develop appropriate economic systems for their fragile and hostile natural environments. Both agricultural and livestock systems evolved practices like crop rotation, pastoral movement and agricultural-livestock combination which ensured a sustainable and renewable use of the environment as well as the recovery of the land’s biological productivity. Given the characteristics of the natural environment and the low level of technological development – and therefore of managerial skills – among local communities, the extremely precarious balance between society and nature is greatly affected by the increasing integration of populations in an international economic system which has failed to provide feasible development alternatives, thus bringing about a socio-economic and environmental crisis instead of development. Traditional agricultural practices gave way to overcultivation, livestock practices to overgrazing , the rational use of natural resources to woodland clearance, and so on.
In short, the socio-economic causes of desertification are related to such inadequate land-use practices as over cultivation, overgrazing, woodland clearance and mis management of water resources.
Because of their increasing foreign currency needs, developing countries devote more land to cash crops, shorten fallow times and expand irrigation schemes. More land for cash crops has meant encroaching on marginal land and expelling their traditional users – grazing animals. Such areas were traditionally used only by pastoralists because of their lower productivity. The extension of cash crops has led to crop homogenization or monoculture, of which the best example in arid and semi-arid areas is groundnut mono culture which has had a negative impact on soil productivity. It is reported that in Senegal productivity has fallen from 1 tonne per acre in 1940 to 0.4 tonne per acre in 1980. Moreover, because of unfavourable groundnut prices on international markets, producers striving to maintain their level of income have had to cultivate larger areas, use more marginal lands, thus reducing the area used for food crops and fallow time and increasing soil deterioration.
The expulsion of pastoralists from previous marginal grazing areas changed grazing and nomadic patterns. Basically, more animals graze more frequently on less extensive pastures. Why more animals? First, because pastoralists regard livestock as a resource base and as a safeguard for bad years, and because the demand for meat in many areas adjacent to arid and semi-arid lands has increased. This has also led to the development of ranching for meat production. Ranching schemes have of course followed the Western model.
These ranching schemes failed to take into account the specific conditions of tropical drylands, their relatively lower productivity, and the time needed for the regeneration of pastures. Moreover, they were meat-oriented whereas the traditional economy had always been milk-oriented. Ranching has been introduced in most cases as an enclave with no relation to the local pastoralists who were in fact expelled. Nor was it suited to the environment or the existing socio-economic system.
The deforestation of arid lands is an additional cause of desertification. According to the FAO, deforestation of arid lands affects 4 million hectares per year, of which 2.7 million are in Africa, and is due partly to the reduction of pastures and partly to the increasing demand for fuelwood which has been accelerated by urban expansion. Woodland clearance for charcoal production is indeed one of the main causes of dryland deforestation. Wood, charcoal and agricultural waste meet almost 100% of household energy needs in the Sahel; indeed 82% of the total energy used by the eight Sahel countries comes from wood. According to the FAO, the present shortage of fuelwood in arid regions is equivalent to the production of 25.8 million hectares of intensive cultivation of fast-growing fuelwood plantations, and if present trends are not reversed, this shortage will more than double by the year 2000. The shortage affects mainly the Sahel, Sudan, Ethiopia, Kenya, Somalia, India, Pakistan and North-East Brazil. Deforestation in turn contributes to soil deterioration and water scarcity. The denuded arid areas are directly exposed to solar radiation, to the winds and rains, and therefore to increased erosion. Deforestation of watersheds reduces the water retention capacity of the soil which, together with erosion, increases silt deposits and reduces the effectiveness of irrigation schemes and water reservoirs. Things get worse when irrigation schemes do not match dryland conditions. Poor management and water logging also accelerate soil degradation.
The combined effects of deforestation, water- logging, erosion, etc, finally lead to a fall in the water table and to salinization problems. The misuse of wells – frequent where nomads are resettled – also compounds difficulties.
Where these additional factors are not present, destructive practices are frequently concealed in the short and medium term and only become apparent over a longer period of time. But a natural disaster or social change quickly brings them to light. Drought and demographic change are the usual triggers.
Eroded, over-exploited, over-grazed and deforested arid lands are more vulnerable to drought. Long and recurrent rain failures cause additional soil erosion, thus accelerating the ongoing process of desertification.
During a drought, the wind erodes the denuded and deteriorated soil. When the rains finally do come, the water runs off quickly from a soil that has lost its retention capacity, taking with it organic material and topsoil, and causing floods, with considerable material damage and loss of life.
A report commissioned by the Ethiopian government blamed that country’s 1972-74 famine not on ‘a drought of unprecedented severity’ but on ‘a combination of long continued bad land use and steadily increased human and stock populations over decades, rendering a greater number of people and their animals vulnerable when drought struck’.1 The same is true of Ethiopia’s latest drought, all the more so as areas affected by severe desertification are slow to recover, especially if the time span between two periods of drought is short.
The relation between drought and desertification is illustrated by the two following examples.
The Masol Plains of Northwestern Kenya have been largely unoccupied since 1974 when Pokot pastoralists were forced to abandon the area because of raids by neighbouring groups. The plains are a ‘zone of insecurity’ and act as a buffer between hostile peoples. Droughts have struck the area since 1973, but the lack of rainfall has had no demonstrable effect on the land and no desertification has occurred. In fact, a study of the area concluded that 1973- 1978 was a period of generally decreasing rainfall, but acacia bush doubled from 24% to almost 50% of ground cover because herders no longer used the area. The study showed that the vegetation biomass of an area can actually increase during a period of drought.
For the same period, 1973- 19 78, the situation in Turkana only 150 km north of the Masol Plains was very different. The drought resulted in high levels of stock loss, large displacements of the Turkana population, the impoverishment of tens of thousands of people and a large-scale famine relief effort.
As the biological potential of Turkana land dropped with the drought, animals were forced to eat every available scrap of edible vegetation they could find. Man helped in this process by lopping off leaf-bearing branches and even by chopping down entire trees. The well-known cycle of soil denudation and erosion then set in and countless tonnes of soil were lost. Many of the dispossessed have gone into charcoal production to make a living, further degrading the land.
During the same period of time under the same climatic conditions of drought, two adjacent areas have therefore experienced completely different types of environmental change. One area increased in vegetation cover, the other suffered increased desertification which resulted in great human suffering. The difference was due to differing land use practices and population densities in the two areas. Desertification was accelerated by drought in Turkana, but it had no adverse effect on the Masol Plains.
In some cases, defensive measures to mitigate the effects of drought can lead in the long run to the acceleration of desertification. For example during a drought, deep boreholes attract herders and their herds. Because the water supply at boreholes can be relatively permanent herds over-graze the area for many kilometers around the well site. Here again it is a case of short-term versus long-term action. Short-term responses, e.g., a quick water supply, may in the long term have adverse effects on the environment. Decision-makers are under pressure to supply water during a drought; but they are often unable to control its use.
The impact of demographic factors on desertification should be examined both from the point of view of density and dynamics.
The population density in arid lands is relatively low compared to that of countries or regions as a whole. It has been shown that there is no direct causal link between growing population density and pressure on drylands.
Although there can be very localized cases of population over-concentration, this should not lead to the hasty conclusion that over-population is a major dryland problem. It has been reported that, out of 24 countries whose population grew by an average of 3% or more between 1970 and 1978, 15 were suffering from desertification and that every year the combined population of the six main Sahelian countries – Senegal, Mauritania, Mali, Burkina Faso, Niger and Chad – increases by 1.4 million. But these figures should be examined carefully. Indeed the average increase fails to reflect the specific situation of arid and semi-arid areas. In fact, scientific research has shown that fertility is lower in most of the Sahelian countries than in the coastal areas of West Africa, in particular among nomadic people. This has been attributed to a number of reasons. Nomads are aware of the effects of rapid population growth for the rather critical balance between society and the environment. Sexual abstinence is reported in countries like Somalia where marriage takes place later in life, dowries are heavy, and long periods of marital separation common. Another factor frequently mentioned is the high level of disease-induced infertility among nomadic Fulani.
More recently, the declining birth rate in arid lands has also been attributed to temporary female infertility because of malnutrition and absence of spouses. Migration seems to have increased considerably in recent years. The long-lasting drought combining with the long-term desertification process has resulted in massive migration. A World Bank report indicates that the response to the desertification process in Burkina Faso has been a massive migration of almost one million men and women (one-sixth of the national population) which reduced population growth by 40%. Similarly, it has been reported from Niger that the number of children born has been reduced by one-third by migration.
Additional factors mentioned in relation to the rate of population growth in arid lands refer to high mortality rates which do not necessarily take place during drought but rather during the rains after the end of the drought and as consequences of diseases like pneumonia, malaria and tuberculosis.
In general, there would seem to be a connection between the lower rates of natural growth among pastoralists and higher rates of migration. The growth of the pastoral population is slower than overall national population growth. For example, while the population of Kenya was growing at a rate of 3.4% a year, its pastoral population growth was reportedly only 2%. Population increase would therefore be only one cause of desertification among many others. Population dynamics as a cause of desertification should be examined in connection with other factors affecting land-use procedures and the changes induced by the creation of new economic links at national, regional and international levels, which finally result in new patterns of nutrition and new habits and technologies.
The current analysis is that human beings are both the cause and the victims of desertification. Yet most analysis has concentrated on the first aspect. There has been a tendency to overlook the effects of desertification on people and social systems unless a major crisis is given television coverage.
Dryland societies have developed economic and social systems which take into account the constraints and potentialities of their natural environments. Their relation ship with the environment is precarious because of the characteristics of the environment and also because of the relatively low technological development which reduces the ability to respond to change and to adopt alternative solutions. These societies tend to adapt to the natural environment rather than to dominate it. Desertification stems from the failure of societies in search of alternative development paths in arid lands. This failure finally destroys society’s hold on the natural system. As Eckholm pointed out, people are forced by circumstances to undercut the ecological base of their future welfare in their struggle for survival. The fight against mismanagement of the land can succeed only as part of a more general onslaught against underdevelopment.
The immediate consequence of desertification is to increase the threat to health and well-being.
Lower productivity of the natural system means that the land is no longer capable of sustaining the livelihood of the population. The immediate consequences are a deteriorating nutritional status and increased morbidity and mortality, especially among the more vulnerable groups such as children and the elderly.
Ghana, like other African countries, has reported higher infant mortality in the drylands than in the rest of the country, which is all the more serious as Africa already has the highest rates of child mortality in the world. Above average mortality has also been reported among young and old people on the Ethiopia-Kenya border. In Brazil, life expectancy in the drylands was 10 years below the national average in 1970 and 14 years below average in 1980, a clear indication that the fight against mortality has been waged mostly outside the drylands. African data show that life expectancy is lower in arid countries than in the rest of the continent. In Sahelian countries, as well as Ethiopia and Somali a, life expectancy at birth is 43 years or less, as against 50 for Africa and 56 for developing countries as a whole. Obviously these indicators do not establish a direct causal effect between aridity and mortality since these countries are also among the least developed in the world. But it does appear that lack of development and a more hostile environment are connected with higher rates of mortality.
The declining productivity of the natural base and its consequences make societies more vulnerable. They have to cope with an extremely uncertain future and they respond to that uncertainty according to their limited capabilities.
For example, for social, cultural and economic reasons, families want at least one son to survive until the average life expectancy age. In the Sahelian countries in the last decade, to have a 95% chance of keeping one such surviving son, a family needed to have five male live births or ten children. In Rajasthan the figure is a little lower – three sons or six children.
The ultimate response to desertification is migration. The consequences of migration and especially its humanitarian aspects should be viewed both from the point of view of the abandoned area and of the receiving area.
In the abandoned area, migration implies the destruction of family patterns. This disrupts population dynamics but also entails the loss of the more innovative individuals. Declining land productivity, increasing labour shortage caused by migration, and the fact that those who stay behind – women, especially – have to devote more time to survival activities (e.g. fetching water and firewood) cause a further fall in agricultural productivity and in overall economic activity. In certain countries such as Mali and Burkina Faso, one-sixth of the population has been uprooted as a result of desertification.
The traditional institutional and social fabric has been destroyed by environmental deterioration and desertification. The precarious balance between people and nature has been upset. In developed countries, a reduction in the agricultural area or the area of cultivable land could be offset by more technological inputs (more intensive culture, greater use of fertilisers). In arid lands the penetration of technology associated with economic schemes ill-suited to the region has contributed to further environmental deterioration and social disruption. In this context, the lack of Research and Development (R & D) for drylands is particularly striking. Humanitarian problems also arise in the recipient areas.
Many people from Burkina Faso and Mali moved to Senegal and Ivory Coast, bringing increasing pressure to bear on poorly equipped services and intensifying marginalization. The same thing happened in Mexico and Brazil. In India, the rapid influx of Hindu settlers into the mainly Sikh state of Punjab from surrounding states affected by desertification helped to inflame Sikh separatist feelings. Refugees from desertification and related disasters often flock to the major cities. In 1974, 20% of Mauritania’s population – 250,000 people – had moved to towns and were completely destitute. The slums and shantytowns of Brazilian cities are full of nordestinos who left the huge drought-stricken region of Northeast Brazil, an area the size of Western Europe.
Increased urbanization also indirectly contributes to desertification. African and Asian city dwellers cook and heat themselves with charcoal and therefore put pressure on local wood resources. The acacia woodlands which used to surround Khartoum in 1955 have been completely eliminated and only isolated woodlots can be found within 90 km of the city. The woodlands around Nouakchott, in Mauritania, have dwindled as a result of an annual 15.8% growth in urban population. Woodland clearance favours sand-dune encroachment and dust storms, which in turn give rise to additional environmental and health problems.
Increasing urbanization also forces governments to adopt food pricing policies with a distinct urban bias, which penalize rural producers depriving them of all incentive to increase or improve production. Urban political power also results in the concentration of investment in urban areas, with the rural areas affected by desertification left out in the cold.
Roughly 50% of the people most directly threatened by desertification live in the Sahel. Because of the attention given to this problem in the Sahel – and the fact that the best data often come from that region – one tends to forget that other parts of the world are also threatened, not all of them low – lying, sub-tropical areas. Particularly at risk are the Andean areas of South America, Brazil, Mexico, and parts of Western Asia and the Indian Subcontinent.
In the Peruvian Sierra, the cold desert is now rapidly gaining ground. The natural forests which once covered this area have virtually disappeared, and the only remaining wood cover is along steep stream banks and other inaccessible areas. Even this is now being rapidly cut. As a result, rivers are heavily loaded with sediment, water flow is erratic, floods and droughts more common, and nearly all the wildlife – previously an important source of protein – has disappeared.
The area supports about six million people – most of Peru’s rural population – who now live in dire poverty.5 Throughout the region, it is nearly always impossible to meet basic needs for housing, food, drinking water and energy. Annual income ranges from $50 to $200. The cold desert in the Peruvian Sierra means that people now spend one day a week gathering fuelwood; 1.3 million people now use llama- or cow-dung as fuel thus depriving soil of fertiliser, as has already happened in India; houses are heated only when food is being cooked; fuel shortage also means that only an average of 1.3 meals per day are cooked; hot water is no longer used for washing clothes and bathing babies. Similar problems exist in many other parts of the Andes.
Wherever it occurs, desertification affects the poorest among the poor, those who are least able to cope. The victims of desertification are those with little or no land, no political power and tiny incomes. Most depend on their ability to scratch some kind of living from land which is already impoverished. For them, survival depends critically on the crops, animals and trees which provide their basic needs. Hunger and disease arrive quickly in the wake of any external disturbance, such as a drought.
As desertification erodes the few resources to which these people have access, social inequalities are magnified. The poor get poorer – forced, for example, to sell their crops or cattle for almost nothing. In Burkina Faso in 1982, traders were able to buy the harvest at a price of30 CFA a kilo. At the height of the dry season, seven months later, they sold it for 120 CFA a kilo.
The case of the women of Burkina Faso who have to walk 6 hours three times a week to fetch firewood has been largely used to illustrate the magnitude of the ecological deterioration and desertification of the Ouagadougou hinterland.
Yet little has been said about the fact that this reflects the social disruption caused by desertification. Disruption affects the individual, the family and society as a whole. At the individual level, there are two main implications, one concerning people’s nutritional and health situation and a second, their economic activities and social roles.
The scarcity of energy to satisfy basic needs results in additional heavy and time-consuming work, as well as changes in nutritional patterns. More effort goes into producing less food. Families only have one cooked meal a day and a number of traditional staples which take longer to cook – and require more fuel – are often replaced by food of lower energy and protein value. Beans are one staple in the process of being replaced. Things are made worse by the lack of adequate substitutes in drylands. Less nourishing food leads to malnutrition which in turn increases the vulnerability of people to different diseases and finally reduces their productive capacity. The penetration of foreign foods or nutritional habits dependent on irregular supplies of imported commodities is often a further problem.
The diversion of women’s activities to the collection of wood and water means a reduction in the productive labour force. This affects agricultural activities – it has been shown that up to 95% of agricultural work in Africa is done by women – food processing (e.g. milk products, salting, grinding etc.), care of domestic animals (goats, sheep) , etc. And on top of their economic activities, women take care of the children and the house. The African woman certainly has no time for social and educational activities, let alone rest, during the day.
The reduction of female productive activities is made worse by the emigration of men or complete families, a new cause of decreasing food production. For the family, ma le migration brings about a structural change as women take on the new role of head of the family. Recent studies show that the trend is increasing in several countries and that in most cases affected families are living below the li ne of absolute poverty.
Changes at the individual and family level tend to cause changes in society as a whole which also has to contend with the penetration of new habits and new technology in the form of such schemes as ranching, cash crops etc. For example, the mechanization of activities traditionally undertaken by women leads to their replacement by male workers .
These changes associated with long-term ecological deterioration and the occasional drought or other disasters deal a death blow to the institutional and control mechanisms developed over the centuries or at any rate make them useless. For example, dryland people have developed long-standing mechanisms for livestock management (nomadism), or for coping with such natural hazards as drought, or birth control mechanisms. These mechanisms are destroyed and replaced by new ones which are not accepted by the local population, require special conditions that do not exist or simply do not work in the specific conditions of dryland societies.
Because of the international causes, dynamics and consequences of desertification, any action to cope must also involve international action.
From the purely physical point of view, it is possible to start from the fact that arid and semi-arid areas are particular ecosystems whose limits are not determined by any national boundaries or international agreements. Areas affected by desertification transcend national boundaries. Moreover, the causality link also has an international dimension: actions undertaken in a particular place have natural and socio-economic effects in different and larger areas.
Even if desertification is a local process, it is also caused or accelerated by the interaction of large-scale dynamic processes in the atmosphere and global weather changes with local characteristics, and also by man’s action on natural physical processes. An understanding of the overall interaction of the macro-climate with local phenomena is also essential. The scale of the problem is such that it can only be tackled globally.
The international character arises also out of the increasing integration of the different areas of the world and their greater interdependence, which determines how land is used, for what purpose, as well as the type of technology applied.
This is illustrated by the increasing reliance on cash crops at the expense of traditional food crops, in order to supply world markets. This trend has serious effects on drylands. The adoption of agriculture and livestock schemes with the incorporation of technologies often ill-suited to local conditions is another harmful development.
Desertification causes demographic changes which are not restricted to a specific country. Thus, people expelled from their natural habitat by desertification frequently move to less affected neighbouring countries or to states which offer economic or survival alternatives.
Finally, the consequences of desertification that in the short term appear purely local, tend to acquire in the long run a global dimension in terms of increases in atmospheric dust, changes in the hydrological system, climatic change, loss of important genetic varieties, loss of production, and a general reduction of the productive base of society. The increasing vulnerability of those directly affected causes social and political instability, contributes to greater inequality in wealth distribution and delays development.