Drought and desertification have an impact on all aspects of life, which shows the extent to which the environment and means of subsistence are interdependent. There are several different types of consequences of drought and desertification, which fall into several categories:
Human consequences
Desertification and drought exacerbate poverty and therefore political instability. In addition to being an important factor contributing o the scarcity of water, drought and desertification lead to the interior displacement or migration of populations, and to social ruptures. This can be a major cause of social instability, resulting in tensions between bordering countries, and even in armed conflict. It is becoming increasingly evident that there is often a close relationship between social conflicts and environmental problems, such as desertification.
More than 500,000 sub-Saharan Africans are currently gathered on the coast of Mauritania in the hope of being able to reach the Canary Islands. Yet this is only the tip of the iceberg since, according to the United Nations, nearly sixty million people will have left the sub-Saharan arid regions for North Africa and Europe by 2020 as a result of desertification.
Go to 5.1 for more information on human consequences
Socio-economic consequences
Degradation of land as a consequence of drought, desertification and climate change affects a significant share of the planet’s arable lands and has a direct impact on standards of living and the economic development of countries. It entails economic losses for farmers, disturbs local and regional food markets and is a source of a social and political instability.
Soil impoverishment caused by drought and desertification perpetuates poverty and socio-cultural breakdown. It can be seen as a relaxation or transformation of traditional structures due to the effects of the market economy (BEDRANI, BESSAOUD, 2006).
The first evaluations carried out on the consequences of drought in France, for example, suggest a figure of one billion euros worth of damage caused to agriculture and another 1.6 billion euros for the damage caused by fires. The impact of these events on cultural heritage and nature remains to be assessed. (Press release, first assessment of drought consequences, reported by the French Council of Ministers).
In North Africa, the annual costs of desertification vary from 1.36% of GDP (Algeria) to 0.4% of GDP (Morocco). In the sub-Saharan countries, they range between 1 and 10% of the agricultural GDP. However, these costs are certainly under-estimated as they only take into account the direct costs of desertification (i.e. only agricultural losses) and not secondary costs.
On a socio-economic level, desertification considerably reduces economic resources. According to recent research by the World Bank, the loss of natural resources of a country in the Sahel corresponds to 20% of its annual GDP. It is estimated that, on a worldwide scale, the shortfall of the zones directly affected by desertification amounts to approximately 42 billion dollars per annum. Economic costs and indirect social costs outside the affected regions, including the surge of “ecological refugees” and a loss in national food production levels, are almost certainly higher.
Go to 5.2 for more information on socio-economic consequences
Environmental Consequences
Since arid zones are prone to desertification, vegetation in these areas has diminished from millions of hectares to just hundreds of hectares, and the fine upper layers of the soil are carried away by the wind. This fine layer, reduced to dust, has drastically increased since the 1980s.
Each year, the Sahara injects nearly a billion tonnes of dust into the atmosphere. More than 100 million tonnes of this dust is carried towards Europe. Dust constitutes a real problem for public health in southern Europe, for example in Spain, because a high concentration of these fine particles degrades the quality of the air that we breathe.
Go to 5.3 for more information on environmental consequences
Cultural inheritance
Many communities that live in deserts or in arid neighbourhoods live in perfect harmony with nature, thanks to their unique knowledge and the upholding of traditions. This harmony is jeopardized by increasing economic pressures and environmental problems due to drought, desertification and climate change.
Yet it is clear that if any community is forced to give up its culture or adopt a new mode of life in order to survive, an invaluable example of world heritage will be lost.
A striking example is that of oasis agriculture, which is considered as cultural heritage in Algeria and across the Maghreb region. Oasis agriculture is facing a multiplicity of environmental threats to its balance and even to its existence.
In these environments the greatest threat is siltation (an extreme stage of desertification). This threatens up to 60% of all urban areas, agricultural land and palm plantations, around 30 km of irrigation canals and 10 km of road.
Consequences on health (Human, animal and vegetal)
Drought and desertification (climate changes impacts) disturb the ecosystem and support the propagation of certain harmful insects and diseases of humans, plants and animals. According to the research results, higher average temperatures will increase the fertility rate and of growth of the devastating insects and the frequency of epidemics, and will allow insects, diseases and adventitious to gain new geographical surfaces.
Human health
Drought and desertification (climate changes impacts) are generally accompanied by a qualitative and quantitative degradation of water resources, and often of the development of epidemics (cholera, malaria etc).
Winds are also, at the time of the sandstorms, vector of ophthalmologic diseases (conjunctivitis).
In addition, as migratory movements empty rural areas, cities fill under often disastrous sanitary arrangements, for lack of infrastructures of cleansing of waste water, of liquid waste processing, management of waste; in these cases the prevention and the medical departments will be largely insufficient.
Drought and desertification (climate changes impacts) disturb the ecosystem and support the propagation of certain harmful insects and diseases of humans, plants and animals. According to the research results, higher average temperatures will increase the fertility rate and of growth of the devastating insects and the frequency of epidemics, and will allow insects, diseases and adventitious to gain new geographical surfaces…
Animal and vegetable health
Drought and desertification (climate changes impacts) cause the decimation of herds for lack of grass. New diseases appear. For example, in countries of the Sahel (for periods of hot summer days), cows generally die at the time when they put low, often calves are premature. The veterinary surgeons as of these areas bound these new diseases to climate change.
The modification of the mode of winds is likely to change the diffusion of insects as well as bacteria and mushrooms vectors of plants diseases. The rise in the winter temperatures will support the multiplication of bee moths drilling machines in the rice systems for example.
Studies reveal that the number of parasitoids – insects such as wasps and flies which lay their eggs on /or inside the caterpillars – falls in the event of irregular rains. However, these parasitoids are very useful in the biological fight against ravagers of many tropical cultures.
The World Health Organization established a clear bond between the strong rains which have affected the major part of the East Africa at the beginning of 2008 and the recrudescence of malaria. Dengue for example, grave disease caused by a virus transmitted by the mosquitoes, reached catastrophic epidemic levels in the Caribbean.
Appearance of mildew in certain areas of potato growing, a disease which is spread under the hotter and wet conditions.
Consequences on soil and biodiversity:
On soil
- Reduction of soils thickness;
- Reduction in the organic matter of soils;
- Reduction in the fertility of the soils;
- Formation of a crust/soils compaction;
- Appearance/growth of the frequency/intensity of winds of dust/formation and movements of dunes;
- Saltiness/alkalization;
- Reduction in quantity and quality of surface and/or underground water ;
- Effects on the pluvial agriculture which occupies an important surface of countries for example Africa (the Sahel and the Maghreb);
- Irrigated agriculture is also affected; water restrictions can be pertaining to irrigation of crops, the domestic uses of water, such as gardens watering or industrial sampling, tourist etc;
- Increase in the sources arid up and the small watercourses;
Deterioration of the relative reflectance of grounds (change of the albedo).
Figure -7-: Map of the geography of water dominant problems in the world (MARGAT, 1990)
On biodiversity
- Reduction in the cover;
- Decrease of air biomass;
- Decrease of production;
- Modification of distribution and frequency of key species;
- Deterioration of the reproduction of key species.
- Firewood is more current and more important (loss of forest and animal species);
On animal (breeding)
- Modification of distribution and frequency of key species.
- Change of composition of herds.
- Decline of the production of cattle.
- the productivity of the cattle.
Global consequences on the human stabilization
Drought and desertification are unquestionable threats for the food security of the 9 billion individuals who will have to be nourished in the middle of the 21st century. Their healthy food would be likely to triple production capacities food from here 2050. Nevertheless, paradoxically, arable surfaces decline. It is provided that the developed countries will have seen passing their arable surfaces from 0.65 to 0.4 hectares through anybody between 1990 and 2010.
Then, desertification and drought exacerbate poverty and thus political instability. It contributes in an important way to the scarcity of water, with interior displacements of populations, the migrations and social ruptures. That can be a major cause of social instability, tensions between bordering countries, even of armed conflicts. It appears more and more clearly that there is often a close relationship between disorders and social conflicts, on the one hand, and environmental problems, like desertification, on the other hand.
Socio-economic consequences
The impact is essentially on:
- The agricultural systems (falls of returns, the quality is affected…)
- Declines of agricultural income: this situation is more marked at the level of countries on agricultural economic base.
The lands degradation of consequence of drought, desertification and change of climate, affects a significant share of arable lands of the planet and has a direct impact on the standard of living of populations and the economic development of countries. It involves economic losses for farmers, it disturbs the local and regional food markets and it is source of a social and political instability.
The soil impoverishment by the effect of drought and desertification is carrying poverty and socio-cultural erosion. It is a relaxation of traditional structures and their transformation under effects of the market economy (BEDRANI, BESSAOUD, 2006).
The first assessments carried out on consequences of drought in France for example, advance the figure of a billion Euros of damage for agriculture and 1.6 billion Euros for the damage caused by fires. It still remains to evaluate the impact of these events on cultural heritage and naturalness.
(Press release, first assessment of drought consequences, reported by the French Council of Ministers).
In North Africa, for instance the annual costs of desertification included are between 1.36% from the PIB (Algeria) and 0.4% (Morocco). In the sub-Saharan countries, they range between 1 and 10 % of the agricultural PIB. These costs are under-estimated altogether. They take into account, indeed, only the direct costs of desertification (only agricultural losses).
On the socio-economic level, desertification reduces economic resources considerably. According to a new research of the World Bank, the loss of natural resources of a country of the Sahel corresponds to 20% of its annual (PIB) gross domestic product. It is estimated that on a worldwide scale, the shortfall of zones immediately affected by desertification amounts to 42 billion dollars per annum approximately. Economic costs and social indirect undergone apart from the Affected areas, including the surge of “ecological refugees” and the national food production loss, could be definitely higher.
The infringement of the systems of production leads to an indisputable poverty, where from a threat of famine. To escape it, men, women and children make appeal to the exodus towards lands more favorable to the life.
The case most illustrating is of that of the migrants en masse from the desert regions of Sahel towards Spain.
It is worth noting that the FAO plans before 2020, a migratory flow about 60 million persons of the desert regions of sub-Saharan Africa towards North Africa and Europe with all that it leads to socioeconomic pressure and thus, political on the territories of reception.
Since zones died desert are subject to the processes more and more accelerated by desertification, the vegetation disappeared on hundreds of million hectares, of new grounds (fine cover) were taken by the wind. By the effect of the wind erosion more and more increased in the weather.
More than 100 million tons of these dusts take the path of Europe in the indisputable consequences both for the health and the environment generally.
Perpetually for a better living environment in development of indigenous knowledge.
Drought and desertification cause sometimes irreversible risks on biodiversity, on the soil and vegetation impoverishment. They involve a modification of floristic composition, a reduction in the covering of the produced biomass and capacities of growth and reproduction of vegetation.
The most alarming consequences with respect to biodiversity appear on:
- The wildlife and domestic fauna, whose management conditions are bad;
- Flora, where certain species are jeopardized;
- Certain waterways, formerly permanent and which became intermittent and upsetting biotopes of many species;
- Migratory birds which constitute a world heritage and which find in the Sahel of the increasingly precarious habitats in residual wetlands.
- Degradation pertaining to an overexploitation of grounds until exhaustion, the overexploitation and the bad use of grounds in arid regions caused a change of climate at the global level which is accelerated by climate changes.
- Degradation pertaining to the overgrazing destroying the vegetable cover which protects grounds against erosion
The soil impoverishment pertaining to the bad practices as regards irrigation involve an increase in salinity, and drain sometimes the waterways that feed the big lakes.
- The deforestation destroys trees which protect the ground against hydrous and wind erosion. Wood is the domestic independent source of energy (lighting, cooking) in many rural areas.
Risks of grasshoppers invasions in the catastrophic consequences on environment and agricultural economics.
Where a risk can activate another one.
The communities which live in deserts or in neighborhoods live in perfect harmony with nature and maintain traditions and single knowledge, these receipts are jeopardized by economic pressures and increasing environmental problems due to drought, desertification and climate change.
Though, it is obvious, that if men are obliged to give up their culture to survive or adopt a new mode of life, a world patrimony of a priceless value will be lost.
The alive example is the one of the oasis ecosystem where the oasis agriculture which is considered as a cultural heritage in Algeria, even in all the Maghreb knows environmental requirements linked mainly to the blocking with sand which compromises in the long term the durability of these ecological entities of human but ingenious conception (ancestral knowledge in: water management, the ground, the local bio-resources and the built).
In these areas, the most important threat is the silting up (extreme stage of the desertification). He threatens, the towns, Ksours, farmlands, palm groves, roads….
So, we attend a threat of preservation of the natural, historical and cultural sites such as: ksour, of a big patrimonial wealth, is also threatened by the blocking with sand, Saoura, Gourara, Touat and Tidikelt in the southwest of Algeria. Ksar de Taghit is considered as a famous historic and tourist site of rupestral engravings).
Their conception allows to emphasize indigenous knowledge, exploited could establish an experience to ease and better manage the impacts of the global warming.
Recapitulation on the process drought / desertification and climate changes:
Having reviewed, all the triggering factors and partial consequences which ensue from it we cannot omit to make the synthesis of the various interactions amplifying the impacts of the risks object of the BE SAFE NET, through the plan illustrating the enchainment and the interdependence of the risks in the deeply moving consequences of the systems of production and socioeconomic organization. As an example, the droughts which raged in 1972/73 in Sahel forced the breeders to settle and the farmers to reduce their food-producing plots of land. The consequences were heavy and amounted to 200 000 deaths for only year of 1973.