What is a desert?
A desert is a desolate stretch of barren or arid land mass of great spread, with little or no vegetative cover, mainly covered in sand, gravels or pebbles or a mixture of these, with practically no form of surface water, having minimal or no significant annual rainfall.
What is Desertification?
Desertification can be defined as land degradation in arid, semi-arid and dry sub-humid areas, resulting from various factors including climatic variations and human activities. It is one of the most serious problems facing the world today. One-third of the Earth's land areas and as many as 850 million of the world's poorest people are potentially at risk. It is a global phenomenon, affecting both developed and developing nations. About 350 million hectares of land is affected by desertification. The most serious environmental problems facing the northern part of Nigeria are desertification and persistent droughts, with dire economic consequences on the entire nation.
Main Causes of Desertification
The main causes of desertification are poor land management and environmental pressure. Dry land soils, because of their inherently low fertility, are particularly susceptible to erosion, especially when their vegetative cover has been removed or degraded. The country is presently losing about 350,000 square meters of its land mass to desert condition, which is advancing southwardly at an estimated rate of 0.6 kilometres a year. Increased population and livestock pressure on marginal lands have accelerated desertification. In some areas, Nomads moving to less arid areas disrupt the local ecosystem and increase the rate of erosion of the land. Ironically, Nomads try to escape the desert, but with their land use practices, ignorantly set off another process of desertification in their new settlement. They will have to move soon taking with them their land use practices, leaving a trail of desert behind, and the chain goes on. Contrary to general conception, desertification is not caused by droughts. Droughts are common in arid and semiarid lands. Well-managed lands can recover from drought when the rains return. Continued land abuse during droughts, however, increases land degradation
Effects of Desertification
Desertification does not only affect dry land areas, tropical forests are equally affected and are fast disappearing. These include jungle, rain forest, mangrove forest, swamp and cloud forest. The rate at which tropical forests are being destroyed is estimated at 21.5 hectares a minute. This is unfortunate, in that trees are vital for life and provide rural population with firewood, medicines, fodder for livestock, timber, ropes, fruits, nuts, dyes, honey and so on.
Trees also have stabilizing effect on environment. When upland watersheds are left bare, heavy rains wash the soil with any crop planted on it into the valleys below. This fills up the riverbeds with silt and floodwaters. In the dry areas, trees provide fertility to the soil and protect it from water and wind erosions. When the rural populace exhausts the supply of firewood, the use of crop residues is resorted to. These residues are important in that they protect the soil by reducing water runoff thereby encouraging percolation. Where the water runs off quickly, soil erosion is accelerated and water levels drop underground causing wells to dry.
Desert encroachment can threaten the livelihood of communities and the survival of a nation. Forty percent of African countries on the fringes of the Sahara Desert are under the threat of drought and desertification. This environmental menace has devastated lands and destroyed many homes. The drought that happened in 1973, as a result of desertification, had claimed more than 100,000 human lives and 12 million livestock.
Desertification and land degradation are the major causes of poverty, hunger, social ills, and loss of bio-diversity as well as natural resources in the affected regions in Nigeria. In July 2008, the Central Bank of Nigeria released the following statistics on poverty in the Northern States of Nigeria:
» The three northern regions have an average poverty incidence of 70% compared to 34% for the three southern regions;
» All the ten states with the highest incidence of poverty are from the north; Jigawa (95%;), Kebbi (89.7%), Kogi (88.6%), Bauchi (86.3%), Kwara (85.2%), Yobe (83.3%,), Zamfara (80.9%,), Gombe (77%), Sokoto (76.8%) and Adamawa (71.7%). As compared to Bayelsa (20%), Anambra (20.1%), Abia (22.3%), Oyo (24.1%), Imo (27.4%), Rivers (29.1%), Enugu (31.1%), Ogun (31.7%), Osun (32%) and Edo (33.1%).As compared to:
» By this statistics, 70% of the people in the north live below $1 (N129) per day. This means that they are earning not more than N 3,870 per month. In terms of number of people, the statistics means that 52.5 million northerners are poor (using 2006 census estimate).
Desertification leads to conflicts amongst communities competing for farmlands. These conflicts can sometimes lead to clashes and eventual loss of lives and properties. The problem also leads to migration from the rural areas to the urban centres.
Within the period of fifteen (15) years, 1960 to 1975, African countries in desert-prone areas had suffered damages from desert encroachment and drought worth US $15 billion. The ground water level put at 10 metres in the 1960's, has dropped to 150 metres as at 2004. Consequently, it has become impossible for some areas to get water from their wells.
As for Nigeria, research findings have indicated that the desert occupies between 35% and 40% of the land mass of the frontline States of Borno, Yobe, Jigawa, Kano, Katsina, Zamfara, Sokoto and Kebbi. The African Institute for Applied Economics, AIAE, had estimated that in 2005 Nigeria had lost about N180 billion annually to deforestation. The AIAE hinged the destructive trend to crop land expansion and the felling of trees for fuel. Real wood fuel prices had doubled in the last two decades in the country due to woodland destruction resulting in an estimated loss of between N45 to N60 billion annually.
Where is the Sahara Desert?
This is the largest, hottest desert in the world, covering around 9,000,000 square kilometres, stretching from the Atlantic in the west to the Red Sea in the east, and bounded by the Mediterranean in the north and the valleys of the River Niger in the south.
What is the temperature regime like in the Sahara?
In the summer, temperatures in the Sahara can get into excess of 50oC in the day and as low as 18oC at night. In the winter months, day temperatures can get as high as 35oC and dip to below freezing at night.
Does it rain in the Sahara Desert?
Yes, annual rainfall can be witnessed in some regions of this vast land area. Total rainfall can be less than 1mm in some regions and up to 15mm or more in others.
How does the sand storm form?
The landforms in the desert change often due to the direction of the prevailing winds and occasional rainfalls. The Sahara Desert has some of the highest sand dunes in the world, some measuring as high as 189 metres. Sand storms occur when fierce winds with speeds in excess of 100km per hour sweep across the desert surface, whip up and carry away tons of sand grains in the process. With neither vegetative cover nor trees to break the storm, the sands in a moving cloud of dust can be transported for tens of kilometres over the desert air, before being dumped only when the wind loses its strength. Sand storms in the Sahara can occur at anytime, but it is typical in the months of April to August.
Is the Sahara Desert expanding?
Observations made with the help of satellite photos show that the desert is growing in size, mostly southwards. This is due to sand storms, prolonged drought, and global warming.
Are there lives in the Sahara Desert?
Yes, both plants and animals can be found in the desert. Plants consist of mostly ephemeral plants known locally as Acheb. Vegetation is found only in places where the ground water reaches the surface, mostly around oasis, Nile Valley, and the Niger Valley. On the other hand, animal species found in the desert include the domesticated camels and goats. Others are Sahara cheetah, sand vipers, scorpions, and monitor lizards.
Can you find water in the desert?
Yes, one can find water in the few oases that are available, the Nile Valley to the east and the Niger valley to the south.
Who are the people of the desert?
There are many nomadic groups in the desert. They move from place to place in search of water and food. They include the Tuaregs, Bedouins, Fulanis, and Nubians. They all wear headgears called the Howli to keep away sands and insects. They are mainly traders and hunters.
Can the people of the desert farm?
Yes. Farming is practiced in certain areas of the desert using drought resistant plants.
Can the desert be tamed?
Yes. Some areas of the desert have been transformed in order to prevent soil erosion.
Activities of Fight Against Desert Encroachment (FADE)
There is no doubt that the Federal, State and Local Governments of Nigeria have been putting concerted efforts in the control of desert encroachment. Over the decades, all the three tiers of government have been involved in annual tree planting campaigns; usually held in July of each year.
At these annual ceremonies, people are given tree seedlings free of charge to go and plant in their homes and on their farms to stop the encroachment of the desert. Colossal sums of money are spent annually. An Arid Zone Afforestation Project (AZAP) was instituted by the Federal Government in 1976 to tackle the problems of desertification through the establishment of woodlots, shelterbelts and windbreaks.
Over 10 million seedlings were raised annually between 1978 and 1984. About 150 kilometres of shelterbelts, 3,680 hectares of woodlots, 24 boreholes, 70 tree nurseries, and Forestry Vocational Schools were established.
Unfortunately, the impact is not significantly felt due to the following reasons:
» The public are not sufficiently educated on the menace of desert to their lives.
» They are not taught how to nurture the seedlings.
» The programme, in most cases, does not include economic trees. Consequently, at the end of the annual "rituals", one finds a lot of tree seedlings thrown away along the streets in the villages.
The ones that got eventually planted are not looked after, resulting in very low survival rate. It is against this background that FADE Africa, in a bid to supplement efforts by the three-tiers of government, decided to involve school children, rural women and youths in the fight against desert encroachment and educational development. FADE's slogan is, "Plant and Own a Tree Today." The idea is to ensure that whoever plants the tree looks after it up to maturity stage. The love for trees is inculcated in the minds of the school children who, in turn, are encouraged to educate their parents on the benefits of planting and caring for trees.
The following programmes have been developed with a view to achieving:
› Control of desert encroachment
› Poverty reduction
› Economic empowerment of women and youths
› Improvement in educational infrastructure, teaching and learning aids.