Aborigine (n.): a native of a country whose ancestors are considered to be the original population of a particular area. They are indigenous or native to the country ie. aborigines in Australia. Back

adaptation (adj.): an appropriate reaction by an individual or a population confronted by a change in environmental factors. Back

addax (n.m.) : an antelope found in Saharan Africa with spiral, ringed antlers. Back

aerosol (n.): droplets or microscopic particles suspended in the atmosphere or air. Back

Agenda 21: an action plan developed by world governments during the United Nations Conference on Development and Environment (Rio de Janeiro, June 1992). Agenda 21 alerts us to the urgent problems faced today and aims to prepare the world for the coming challenges of this century. It reflects a global agreement and growing political awareness at the highest level for co-operation in the domain of environment and development. It is primarily a role of government to effectively implement the action plans. Back

agro-forestry (n): method of food production combining tree and shrub plantations and the farming of low-lying herbaceous plants. Agro-forestry is often recommended to enhance the biodiversity of agricultural ecosystems and improve production while reducing land degradation. Back

alpaca (n.): a cud-chewing grazing mammal domesticated in South America and closely related to the llama. It possesses a long fleece of fine, long wool. The alpaca belongs to the family of Camelidae (camels, dromedaries, llamas etc.) Back

alternative energy (n.): the exploitation of naturally occurring energy sources such as solar energy, wind energy, hydraulic energy as a less polluting alternative to fossil fuels. The availability and possibilities of this form of energy are considerable. Back

amphibian (n.): a group of scaleless four-legged vertebrates of which the young (larvae) live in water while the adults live on land. They are made up of families of newts, salamanders, frogs and toads. Back

antelope (n.): a ruminant herbivorous mammal possessing hooves. They are particularly found in the steppes of Asia and Africa. Back

arable (adj.): land fit for ploughing or crop production. Back

arboretum (n.): a park designed to conserve a variety of local and exotic tree species. Back

arboriculture (n.): tree plantation for cultivation, particularly fruit trees. Back

arid (adj.): characterized by lack of rain. In scientific terms: rainfall is less than 200 mm/year thereby constituting an arid climate. Back

aridity (n.): climatic conditions marked by low rainfall (less than 200 mm/year). Back

atmosphere(n.): the gaseous envelope that surrounds the earth. Back

avalanche (n.): a mass of matter (snow, sand, earth) hurtling down a slope at high speed. Back


baobab (n.): a tree found in Africa and specially adapted to drought. Its swollen trunk stores water while the twisted branches are reduced in size. Almost all of the baobab can be used (trunk, fruits, leaves). Back

barley (n.): a flowering grass cultivated as a cereal for food and used in the production of beer. Back

biogaz (n.): domestic or commercial gas obtained by the conversion of organic waste into fertilizer and gas used to drive a generator. Back

biological diversity or biodiversity (n.): the variety and variability of living species (animals, plants, fungi, micro-organisms) that make up an ecosystem. Back

biosphere (n.): a limited space made up of air, earth and water and in which life is possible. Back

biosphere reserve (n.): a zone supporting terrestrial ecosystems, recognized internationally by UNESCO as a favoured site for research and the promotion of balanced interaction between man and nature. Back

Boschiman (n.): hunter-gatherers living in the semi-arid regions of the Cape, South Africa. Back

bunding (n.): the act of constructing a man-made embankment or dam (bund). Back


cactus (n.), cacti (pl.): family of plants found in the Americas with green fleshy stems in the form of columns containing water reserves. Their leaves are reduced to thorns to help conserve water. Back

capacity charge (n.): a theoretical value representing the load limits (animal population density, agricultural density…) that an ecosystem can support without becoming degraded, taking into account the resources available in the local environment. Back

cholera (n.): a bacteria responsible for a contagious disease acquired by ingesting food or water contaminated by the vibio cholerae bacteria. Back

CILSS: Permanent Interstates Committee for Drought Control in the Sahel (Comité permanent inter-états de lutte contre la sécheresse dans le Sahel). Created in response to the Great Drought of 1968-1993, its mission is to invest in research and food security and to combat the effects of drought and desertification. The CILSS brings together nine countries in West Africa: Burkina Faso, Cape-Verde, Chad, Gambia, Guinea-Bissau, Mali, Mauritania, Niger and Senegal. Back

clearing(s) (n.): the act of removing trees or vegetation from a natural ecosystem, such as a forest or woodland, to render it fit for cultivation. Back

clearings ( an area that has been cleared by removing trees or vegetation present in a natural ecosystem, such as a forest or woodland, to render it fit for cultivation. Back

cochineal (n.): a small flattened insect that feeds on the sap of several plant species, notably the prickly pear. It gives its name to a dark red substance used as a colouring for foodstuffs extracted from the insect. Back

colonization (n.): a phenomenon by which a small portion of a plant or animal population is introduced to a new ecosystem and settles until it becomes omnipresent, found almost everywhere. Back

compost (n.): natural fertilizer made from organic plant and animal waste used to fertilise crops. Back

condensation (n.): the transformation of water vapour (gas) into water (liquid). Back

Conference of the Parties (n.): It is the highest decision-making body as established by the Convention. It brings together the representatives of all the governments having ratified the Convention (UNCCD) and administers its application. Back

continental climate (n.): weather conditions or patterns characterised by very cold winters and very hot summers, the transition seasons being brief. Regions characterised by a continental climate are generally distant from the sea and ocean. Back

contour lines (n. pl.): imaginary lines that follow the same altitude or height above sea level. They can define the edges of terraces in terrace farming. Back


deforestation (n.): the process whereby people destroy forest ecosystems by activities such as bush and forest fires that clear areas for cultivation and the over-exploitation of wood for energy needs. Back

delta (n.): the zone that divides a river in two or more branches before it flows into the sea. Back

desiccate (vb.): to dry up or to become dry. Back

dike (n.): a man-made trench or ditch or a raised mound formed to prevent flooding. Back

dromedary (n.): a plant-eating mammal, possessing a hump on its back, adapted to drought conditions. They belong to the family of Camelidae (alpacas, camels, llamas etc.). Back

dry sub-humid (adj.): characterized by heavy seasonal rainfall and rainfall variations of less than 25% from one year to the next. Back

dysentery (n.): an intestinal infection caused by germs or amoebae (micro-organisms of ever-changing shape). Back


ecological monitoring (n.): the control and follow-up of changes occurring between the natural and physical environment of an ecosystem and their interaction. Back

ecology (n.): a study of inter-relationships between living organisms and their environment and the mechanisms that explain their distribution, numbers and behaviour. Back

ecosystem (n.): a group of living organisms interacting with their physical and chemical environment in which they evolve. Back

encroachment (of the desert) (n.): the advancement of the desert fringe towards arable lands

environmental education (n.): teaching relating to knowledge on topics such as ecology, desertification, climatic change, sustainable development etc. Back

erosion (n.): the removal of topsoil and the breakdown of rocks due to the action of the wind (wind erosion) or water (hydraulic erosion). Back

euphorbia (n.): herbaceous plant of the tropics, often tree-like, they ressemble cacti of Latin America. Back

evaporation (n.): the transformation of liquid water into water vapour in the atmosphere without being absorbed by living organisms. Back

evapo-transpiration (n.): the return of water into the atmosphere as vapour, by evaporation from soil or water bodies, and emissions of plant transpiration. Back

evolution (n.): the cumulative change in the characteristics of a population of organisms over succeding generations resulting in the adaptation of populations to variations in environmental factors. Back

exotic species (n.): foreign species found in a given biogeographical region that has been accidentally or voluntarily introduced by humans. Back

extensive cropping (n.): a method of crop production that enlarges agricultural areas to increase productivity. Extensive cropping is often accompanied by deforestation and clearings that increase arable lands. Back


fallow (n.): the practice of voluntarily interrupting farming activities on the land for a period of two years or more so as to allow the natural vegetation cover to restore the soil when it has been exhausted by a succession of crop production or overgrazing. Back

FAO: Food and Agricultural Organization of the United Nations contributes to improving agricultural productivity, food security and the living standards of rural populations. Back

fennec (n.): a small African desert fox with large ears. Back

fertility (n.): in the case of land, it is the ability of the soil to support and sustain life. A fertile soil contains enough organic matter and minerals to assure plant development and growth. Back

fertility rate (n.): number of infants born to a woman of child-bearing age; if she gave birth to the number of infants corresponding to the estimated age-specific fertility rate during the given period. Back

fodder (n.): grass, straw and hay that comprise food for cattle. Plants upon which animals can forage can be used as fodder. Back

foggara (n.): an underground gallery that taps underground water reserves (or aquifers) from which it drains water towards the fields to be irrigated. Back


GDP (gross domestic product): an indicator of income levels. The sum of products and services produced by a country during a period of one year and calculated before the deduction of economic expenditure. Back

GIS: a computer operated Geographic Information System producing maps, pictures and virtual images that help better define a situation or problem. Back

gravity (n.): force of attraction exercised by one body upon another ie. a body that is strongly attracted and moves towards the earth. Back

groundwater (reserves) (n. pl.): layer of underground water, these so-called aquifers can be found at varying depths according to its source. The groundwater reserves play an important role in the drylands where they are the major source of water. Back

gullies ( channels worn (shaped) by running water. Back


habitat (n.): a place where living plants, animals and humans are found. Back

halophyte (n.): a plant adapted to salt-rich soils, often termed salt-tolerant plants. Back

harmattan (n.): a dry, dusty wind from the desert in West Africa. Back

herbicide (n.): a chemical product that acts as a weed killer. Back

horticulture (n.): the cultivation of fruits, vegetables and ornamental species. Back

humus (n.): a brown coloured layer at the soil surface made up of decomposed vegetation rich in organic matter and nutritive elements that enrich the soil. Back


IGAD: the Intergovernmental Authority on Development, which aims to support regional efforts to combat the effects of drought and desertification. The members of State are: Djibouti, Eritrea, Ethiopia, Kenya, Uganda, Somalia and Sudan. Back

impluvium (n.): in Roman dwellings, it was the basin placed below the open space in the roof to receive rainwater. Back

infant mortality rate (n.): the number of deaths of infants and children under the age of one year old, in a year, out of 1000 births in the same year. Back

intensive agriculture (n.): a method of food production based on crop farming and cattle rearing in a way that maximizes production in areas of reduced size in the short term. Intensive agriculture often leads to overgrazing, monoculture and the end of fallow periods that exhausts the land and reduces fertility and production in the long term. Back

intensive cropping (n.): crop production to increase the productivity of small agricultural plots. Intensive cropping generally leads to land degradation. (See intensive agriculture). Back

irrigation (n.): a technique used to collect and distribute water in the drylands by various methods. Back


jerboa (n.): a desert rodent with long hind legs and a long tail that helps it balance for jumping. Back


land degradation (n.): a process leading to a loss of soil fertility that can be linked to a drop in the concentration of organic matter in the soil, an accumulation of minerals and/or a change in the soil structure by desiccation or erosion. Back

lichen (n.): a plant composed of a fungus and an algae. It is often used as an indicator of pollution-free environments. Back

live fences (n. pl.): barriers formed using live trees or shrubs to counter the effects of wind and erosion while protecting crops. They can be constructed as cattle enclosures and provide fodder to the animals. Back

local species (n.): species adapted to the local biogeographic region, called indigenous species of the region. Back


malaria (n.): a serious illness caused by a parasite and transmitted by the mosquito, Anopheles maculipennis. Malaria occurs pratically throughout the world’s tropical zones and affects several hundred million people. It can be fatal if not treated. Back

mallee (n.): any tree belonging to the genus Eucalyptus. Also mallee scrub, an area where mallee forms the predominant vegetation. Back

malnutrition (n.): the result of insufficient and ill-adapted food, in other words an inadequate diet that can lead to sickness. Back

Mesopotamia (n.): a once fertile region of Central Asia situated between the Tigris and Euphrates valleys. Often marshy, Mesopotamia was irrigated since antiquity. The fertility of the region established the foundations of future civilizations. Their contributions include the wheel, glass, the alphabet, calendars, bronze, iron, poetry, farming and irrigation. Back

metabolism (n.): the sum total of the physiological and biochemical processes in an organism. Back

microclimate (n.): the climate of a small or restricted area whose climate is different and distinct from the surrounding area. Back

micro-organism (n.): a plant or animal that is invisible to the naked eye and can only be seen through a microscope. Back

migration (n.): seasonal displacement of an animal from one region to another in order to reproduce, search for food, or seek a better climate or living conditions. Human populations are also said to migrate for economic or political reasons. Back

millet (n.): a grass cultivated as a cereal or foraging plant. Back

minerals (n. pl.): solid inorganic particles that make up rocks of the terrestrial crust. Back

monoculture (n.): the growing of only one type of crop, or a large area over which it is grown. Back

moufflon (n.): a big-horned wild sheep. Back

mulch (n.): a loose material such as dung mixed with straw, laid on the soil around plants to protect roots, retain moisture and control weeds. It often has a nutritional function for the soil and therefore the plants. Back


Neolithic (n. and adj.): a prehistoric period corresponding to the Stone Age between 5000BC and 2500BC and the beginning of agriculture and cattle rearing. Back

NGO (n.): a non-profit non-governmental organisation whose work is carried out independently from governments. Back

nitrates (n. pl.): minerals salts of nitric acid, they are nutritive mineral elements for plants. In zones of intensive agriculture the use of nitrate based fertilizer can frequently lead to pollution of surface and underground water tables. Back

noria (n.): a long chain of buckets or receptacles on a wheel used for raising water form a stream into irrigation channels. Back

nursery (n.): an area reserved for the cultivation of trees. Back

nutrients ( a term that includes various nutritional minerals vital to the well-being of organisms. The major nutrients for terrestrial green plants are phosphates, nitrates, potassium and mineral salts. Back


oasis (n.): plural form: oases. A fertile ecosystem situated in a desert zone around a watering hole or in depressions where groundwater reserves are close to the surface. Back

oilseed (n.): an oil-rich plant from which oil is extracted for consumption. Back

orchard (n.): an area reserved for the cultivation of fruit trees. Back

organic (adj.): that comes from living organisms. Back

organic matter (n.): substance originating from living organisms. Back

ornamental species ( a plant species that is intended to be decorative and not serve as a foodstuff. Back

ostrich (n.): the largest bird in the world found, it is found in the desert savannah of Africa. It is flightless but is remarkable for its speed in running and can be domesticated. Back

over-exploitation (n.): improper and excessive use leading to the degradation of that which is used (land, water, vegetation). Back

overgrazing (n.): excess feeding or foraging of domestic animals leading to the degradation of vegetation cover. Back


pastoralism (n.): a method of farming based on cattle rearing, it depicts a nomadic, rural lifestyle. Back

percolation (n.): penetration and filtration of water through pores of rock or earth. Back

perennial (n. or adj.): a plant that lives for more than two years, or simply, coming back year after year. Back

permeability (n.): the ability to have water, liquid or air pass through or penetrate a barrier like the soil through its pores. Back

pesticide (n.): a dangerous chemical product intended to eliminate pests usually animals (insects) that damage crop harvests and are therefore considered a nuisance. Pesticides are a major contributor to pollution. Back

piezometer (n.): an instrument usd to measure the water level in groundwater reserves. Back

pilot project (n.): a leading experimental programme whose goal is to measure results so that further action can be planned, thereby applying the knowledge acquired over the initial testing stage. Back

plant succession (n.): the progressive pattern of different forms of vegetation cover that dominate a given ecosystem. It has been observed that pioneer species, small annual plants, initially colonize virgin lands. They are then succeeded by herbaceous species then by shrubs and finally by trees. Back

planting out (n.): the transfer or transplantation of young healthy plants as seedlings from small pots into the soil, often in a nursery. Back

ploughing (n.): the act of turning up the soil to make furrows or ridges that aerate the soil and prepare it for sowing. Back

poliomyelitis (n.): an infectious and contagious viral disease that can lead to paralysis. Back

polyculture (n.): the simultaneous production of several different crops and types of livestock in one region. Back

population growth rate (n.): increase or decrease of a population. Population growth = (birth rate – mortality rate) + (rate of immigration – rate of emigration) Back

potable (adj.): fit for consumption. Potable water should be clean and not endanger the health of those who drink it. Back

pulses (n. pl.): protein-rich plants capable of growing on poor soils due to their ability to fix nitrogen present in the atmosphere. Acacias, lentils, soy and peas are all examples of pulses. Back


rain-fed agriculture (n.): a method of crop production that relies on natural rainfall without the need for artificial irrigation systems. Back

reforestation (n.): tree replanting activity particularly in an area previously forested or woody. Back

rehabilitation (n.): to restore the state of something into its original form. For example, the rehabilitation of degraded lands by reforestation helps the fragile ecosystem to regenerate. Back

run-off (n.): to cause to flow out, usually relates to surface water flow from rainfall. Back


SADC: Southern African Development Community. This organization aims to achieve development and economic growth and enhance the standard and quality of life of the peoples of Southern Africa. The member States are: Angola, Botswana, Democratic Republic of Congo, Lesotho, Malawi, Mauritius, Mozambique, Namibia, South Africa, Seychelles, Swaziland, Tanzania, The Zambia and Zimbabwe. Back

Sahara and Sahel Observatory (OSS): Its primary objective is to promote the development and the optimisation of data intended for desertification control. Its members are: Algeria, Burkina Faso, Cape Verde, Chad, Djibouti, Egypt, Eritrea, Ethiopia, Gambia, Guinea Bissau, Kenya, Libya, Mali, Mauritania, Morocco, Niger, Uganda, Somalia, Sudan, Senegal and Tunisia. Back

Sahel (adj./n.): the group of countries located south of the Sahara desert, generally between the desert and the Savannah regions. Back

Sahelian (adj.): concerning the countries south of the Sahara desert, generally between the desert and the Savannah regions. Back

salinity (n.): mineral salt concentrations in the soil or water. A high salinity results in the loss of fertility and pollutes underground reserves. Back

satellite (n.): a man-made device launched into space and revolving around the planet. It can receive and send information, take photographs, measure temperature, magnetism etc. Back

scirroco (n.): a hot, dry, dusty wind blowing from North Africa to the North Meditteranean coast. Back

self-help (n.): doing things for oneself without assistance from others. Back

self-management (n.): administration and organization of an enterprise or activity by the very workers involved. Back

semi-arid (adj.): characterized by rainfall not exceeding 500 mm/year (winter rains) or 800 mm/year (summer rains) giving rise to a semi-arid climate. Back

senecio (n.): any plant from the genus Senecio, distributed throughout most parts of the world. Back

shelterbelt (n.): fence of planted trees and shrubs that create a barrier against outside influences (fire, sand, wind, animal invasions etc.) (See the case study from China). Back

slash and burn (n.): a crop farming method that consists of setting fire to a wooded area to transform it into agricultural land. Back

sorghum (n.): a drought-resistant plant cultivated for human food consumption and found in Africa and Asia. Back

steppes (n.): a dry grassy ecosystem that is generally treeless due to low levels of rainfall. This type of landscape is found in Central Europe and Asia. Back

sub-humid (adj.): characterized by rainfall whose total equals at least half the evaporation rate but less than the total loss by evaporation resulting in a sub-humid climate. Back

subsistence (n.): a subsistence activity or subsistence living implies production methods that barely produce enough to meet the basic needs of the farmer or worker. There is no surplus that can be sold and no profits are made. Back

sub-tropical (adj.): situated close to the tropics. The sub-tropical climate is characterised by hot temperatures and the long dry season. Back

succession (n.): the colonisation of a physical environment by a series of vegetation or plant communities until equilibrium is reached. Back

Sudano-sahelian climate (adj.): the predominant climate prevailing in the Sahel, the southern regions between Senegal and the Sahara. It is characterized by a long dry season and one very brief rainy season. Back

sustainable agriculture (n.): method of food production based on crop cultivation and cattle rearing that uses natural resources in a way that maintain and replenish (renew) them over time without jeopardizing the future of coming generations. (See sustainable development) Back

sustainable development (n.): a means of progress that takes the environment into consideration by its wise and rational use, based on the reasonable and moderate exploitation of nature and its resources to ensure the continued maintenance of biological productivity in the biosphere. Back


topography (n.): the detailed study of, or description of the features of an area. Back

traditional knowledge (n.): the wisdom and experience base which represents the accumulated know-how of ancestors of a given population and is transmitted from one generation to another. Back

transhumance (n.): periodic migration of cattle following changes in the seasons, from summer to winter or from winter to summer pastures. They are often led by nomadic populations. Back

transpiration (n.): a phenomenon in which liquid water is absorbed by an organism and is released into the atmosphere in the form of water vapor. Back

troglodytic (n.): a cave dwelling either formed naturally or artificially carved out from the rock. The cave dweller is known as a troglodyte. Back

Tuareg (n.): a nomadic people of the Sahara in Africa. Back

tumulus (n.): a structure formed by the accumulation of earth or stones above a tomb during the Bronze Age

typhoid (n.): an infectious disease, often occuring in epidemic proportions characterized by high fever, loss of concentration and serious digestive disorders. Back


UMA: Union maghrébine Arabe. Member States are: Algeria, Libyan Arab Jamahiriya, Morocco, Mauritania and Tunisia. Back

UNDP: United Nations Development Programme. Implements projects for social and economic progress and the alleviation of poverty. The organization annually measures the indices (GDP, HDI) on the development of every country in the world. Back

UNEP: United Nations Environment Programme. Encourages the application of environmentally friendly activities around the world. Back

UNESCO: scientific programmes contribute to combat desertification, notably the Man and the Biosphere Programme (MAB), the International Hydrological Programme (IHP) and the International Geological Correlation Programme (IGCP). Back

urbanization (n.): the development of cities and towns and their infrastructure leading to the concentration of the population in these areas. Back


vegetation cover (n.): the collective term for vegetation (especially low growing plants) covering the ground. Back

vegetative (adj.): concerning the growth process and maintenance of plant and animals. Back

vertebrate (n.): an animal possessing a spinal chord, including fishes, amphibians, reptiles, birds and mammals. Back

viticulture (n.): the cultivation of the vine (grape). Back


wall chart (n.): updated information presented in the form of a poster that is available for all to read. Back

water tribunal or assembly (n.): set up by the local community, it reunites the local population to make collective decisions on the istribution of water according to the specific needs of the community. A water ‘agent’ is appointed who calculates and measures the quantity of water required daily by the locals for washing and drinking etc. Back

WMO: World Meteorological Organization, a United Nations agency. Encourages scientific research, climate change analysis and promotes the world exchange of meteorological data. Back

World Heritage (n.): natural and cultural sites listed by the UNESCO World Heritage Convention for their exceptional features of scientific, cultural or aesthetic importance so that they can be preserved for humanity. Back


zebu (n.): a type of humped domestic ox, originating in India, it is found in China, the east coast of Africa and Madagascar. Back