Desertification in North Darfur State

1. 35
Desertification in North Darfur State
Salih Ahmedai Abdalla, Faculty of Environmental Sciences and Natural Resources
Al-Fashir University-Sudan
صالح احمداي عبدا لله
كلية علوم البيئة و الموارد الطبيعية – جامعة الفاشر
التصحر في ولاية شمال دارفور
مستخلص البحث
مناا ولاية االلاداا ولا شبهااحبلاواافي لالااالشي لاالاش اا ولايلا اا لاهن لاهقاا فيلاالاشلأجااءش لا
شلجنحبيااللايلاملاالأولاشلأمااا بلاش ياانح للا اا شي لالاباا لالا 011 لا–لا 011 لاملااولايان اابلاب باا لاالالا
- ك يللاااحولاشلأما بلايلا بج تلاشلحلشبفيلاش ينح للالمحااللاش ا واللالااولاش اا فيلالا 0531
9115 لاملاب لاإلىلاشةببا علالابمللأولانصفلا بجللامئح ل.لايعلأ لاش يك نلا 9.0 لامليحنلانيا للالا
ع ملا 9115 ملابمتح طلالا 01 لاوخصلا كللاكيلحم لاملبعلايلا تض عفلاش يك نلاكاللالا 93 لا
ااانل.لايش باااللابملياااللايرينياااللاب اااحبيللاالاوااا ب لاشلأي اااللايلابلك نياااللا.لا اااءبعلاش ااالأل لاالا
شلأبشضيلاش لمليللاييمثللاش غ ش لاش لئيسلا ليك نلايلامللأولاش تهاكلاش ال لام لاش غاولا 931 لا
كجااو / لاش يااانل.لالايمتح اااطلاإنت جياااللاش ااالأل لاالاش حة اااللا 01 لاكجااو / لا لاااالأشنلاهاا لاش اااا فيلا
9110 -0595 م،لايش بفيلا 911.1 كجو / 0551 لاملايلا حجالألالا - لا لالأشنلاه لاش اا فيلا 0590
91 %لا - نقصلاالاإنت جياللاشلمح لايللا.لايما لاشتتحعاعلا نلالابانخا لاإلانت جياللاشلمح لايللابا لالا 3
9191 م.لايلابقلأبلاش ثليفيلاشلحيحشنيللالابححش يلا 01 لامليحنلالاب س.لالالا - ه لاش ا فيلام 9111
بأثلتلاية للاد ولا شبهحبلاب لجا فلايش تصااللالامنا لابلأش اللاش يافيلين تلا تا لامنتصافلالا
ش ث نين تلام لاش قلنلاشت ضيلايبل عفيتلابللألاذ بلامحج تلام لاشلجاا فلا تا لاعا ملا 9111 ملا.لا
يبللضتلاش حة للا للأ لام لامحج تلاشلجا فلايشلمج ع تلالالاولاش ا فيلا 0500 - لا 9111 لام،
لايوااهلأتلاش حة االلا يبشتلاجااا فلامتفي عاالأفيلايش االللاشةنت اا بلالاااولالا 0509 - لا 0595 ملا،لا

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-0511 لا 0510 لاملا.لايبلتلاذ بلا ليلللام لاشلجا فلاشلمحلأي لاالاش اا فيلالا 0519 - لا 0515 لا
ملايشلأعحشملا 0551 ملايلا 0555 لاملا
ماا لاشلأ افي لاش لئييااللا لتصااللاش تح ااعلاالادبشعااللاش االأل لاالاشتناا ر لاعليلااللاشلأمااا بلا
يشله م يللايش تيلاشمتلأتلاد ةًلا ت لالطلاشلأما بلا 031 لاملو،لايعلأملاإبفي علاش لأيبفيلاش ءبشعياللالا
يش لعيلاشلج ئللايعاعلاشلأوج بلاش تيلا قلأبلابحح يلا 99 %لالااولاش اا فيلالا 9111 لا- 9113 م،لا
ي قلأبلامللأولاش اقلألايلاشلإدش للام لاجملللامي للاش غ با تلا 51 %لايلاشنحيالتلاشتنا ر لاش لعح اللالا
31 %لالايلاشنلالأمتلاشتلشعا لاالابلا لاشتنا ر لا.لالا لااا الاش اتغ شتلابالأم لالا - بححش يلا 91
يإبااا فيلا لغاااا لاش نفيااا بيلاينااااحتلاشلحيحشنااا تلايبلل اااللاش باااللالايد ااا فيلاك ياااللاش غفيااا بلاش لااا لا
يشلمج ع تلايشلهجلفيلايلانءي لاش يك نلاإ يلاشتن ر لاشلجنحبيللاي ه لاشلأي للايشلحلي لاش قفيليل.لالا
تك هاللاش تصاللاةلابلألام لايضعلاعلأفيلابلشمجلاب للام ليع تلاش ت ج لاشلحكحميلا
يش لبيلايإع فيلالابل لا اءشملاش صا الاش للب ايلايدبشعاللاش نخي اللايشلإبوا لايلاش تحعي اللايلاعي الالالالالالالالا ملا
م ليع تلاش تن يللاش ل ايللاشتتك ملللاي ص لاشتي ا.لالا
Abstract
The climate of North Darfur State is semi-desert and desert to the north. The rainfall in about 200-400 mm with a rainy season of 2 to 2.5 months. It had a population of 2.1 million according to 2003 census and the population growth rate is about 12% per year and the population density from 3 persons /km2 in 1956 to 18 persons / km2 in 2003.
Farmers practiced cultivations of millet, sorghum, sesame and groundnuts during the rainy season and they keep livestock. Cultivation of crops reached areas receiving 150 mm and crop rotation is reduced resulting in decrease of soil fertility and yields. The spread of rain-fed cultivation farmers used to cut the trees often fired the bush destroying most trees and seedlings. They used large amount of wood

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for fuel, constructions, tools and fencing. Subsistence needs are considered to be about 250 kg of cereals/person/year. Millet yields in North Darfur State about 60 kg/fed during the period 1973-2004 and for sorghum 111.6 kg/feddan during 1970-1990. Livestock number about 40 million. Average annual deforestation rate was 77% between 2000 -2005 and Darfur has lost more than 30% of forests since Sudan's independence and rapid deforestation is going.
The destruction of the vegetation through pearl millet cultivation, overgrazing and clearing of woodlands led to the loosening of the sandy soil and its exposure to the influence of strong winds. The dominant processes are wind and water erosion. The amount of the dust in air has increased. Sand accumulation is often regarded as the actual desert encroachment because the newly formed dunes encroach on settlements and fields.
1-Environmental setting
Greater Darfur consists of five states North, Central, East, South and West Darfur. North Darfur State lies between latitudes 12º N and 20º N and longitudes 21º 52¯ E and 27º 54¯ E and had a population of 2.1 million according to 2003 census. The climate of the state is semi- desert (a typical Sahel). In the Sahel zone three divisions are recognized. The sub-desert (200mm), the typical Sahel( 200-400) mm with a rainy season of 2 to 2.5 months, and the Sahel of Sudanese border (400-600) mm with a growing season of 3 months. The main features of the climate are a short rainy and highly variable season, between July and September with unpredictable droughts and 90% of

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the rainfall falls between July and September. The key features, which adversely affect agriculture, are the low and erratic rainfall. The economy of the state is based on traditional rain-fed farming, animal rearing and petty trading. The elevation of the state is about 600-900 m above sea level and the topography of the region is interspersed with various hills and mountains. Jebel Marra which is located between latitudes 12° 25 ′ N and 13°N and longitudes 24°10 ′ E and 24° 12 ′ E, constitutes a volcanic mountain range about 135 km long and 80 km wide with maximum elevation of 3042 m and covering an area of about 8000 km2 .
The region is situated in a transitional zone between the northern Sudan savannah and desert vegetation. The vegetation consists of annual grass and scattered bush steppe in the north, gradually merging in the savannah with perennial grasses and scattered trees (White, 1983). The vegetation classes based on structural type are: Woody grassland, with trees more widely spaced up to 15 m, and different species includes many broad-leaved types, which contains species such as Combretum , Terminalia, Baobab, anddifferent species of Acacia. The main types of grasses are Aristida. Ergrostis and Cenchrus. The trees are mostly including Acacia, Zizphus and Commiphora spp., Acacia Senegal is regarded as the characteristic tree in the sandy soils, in areas rainfall between 200 -450 mm, Aristida sieberana is dominated in clay soils, acacia mellifera is common. Semi-desert: on the margins of the desert, consist of Acacia,

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Commiphora, Hymphaene ,Salvadora persica (Harrison and Jackson, 1958).
Soil surveys carried out by Hunting Technical Services (HTS, 1976) divided Darfur region into six main soil classes: desert soils, stabilized dune sand, cracking clays, riverine soils, Nagga and alternating non-cracking clay soils. The two main soils in North Darfur State are the sandy soils and the dark clay soils. The sandy soils are mainly stabilized sand dunes known as qoz lands. They are deep and often uniform over vast areas forming the different dunes. Some dunes are quite pronounced, while others are heavily eroded and almost flat and having red, yellow and white. The dunes lie in one main direction, like the recent ergs or they may have a circular form without any specific orientation. They consist of 60% coarse fine sand and less than 10% clay. Soils developed on the recent erg have a coarser texture than those developed on materials deposited later. Plants can satisfactorily grow there but those with shallow root network dry up at the end of rains. Erosion by wind or water is high where the vegetation has been consumed or destroyed by livestock around watering places and nomads encampments. Large quantities of water can infiltrate at the collection points, contributing to growth of trees or feeding reservoirs. The landscape is generally flat and the dune slope between 1-3 % in various directions. These soils have been subjected to inappropriate management, leading to wind and water erosion (Brown and Hall, 1991). This was followed by organic matter and nutrient losses, which in turn affected soil physical, chemical and

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thermal properties. The main causes of land degradation are inappropriate land use, mainly unsustainable agricultural practices such as clearing of agricultural lands, especially mechanized clearing, over-grazing, fuel wood extraction, building of settlements and bush burning. These wide spread effects on both cover and composition of vegetation. The intensification of these events due to human and ruminant's population has led to shortening of fallow periods, thereby limiting the regenerative capacity of soil flora and fauna. Also, the shortening of fallow periods under intensive cropping weakens the natural ability of soil to recover its fertility leading to land degradation, lower crop productivity and reduce income (Clunies- Ross and Hildyard, 1992). The main on-site effect of land degradation is the decline in yield which can amount to more than 50% or an increased need for inputs to maintain yields (Olaitan and Lombin, 1984). Moreover, the addition of fertilizers alone cannot compensate for all the nutrients lost when top soil is eroded (FAO, 1983).Where degradation is serious the plots may either be abandoned temporarily or permanently or converted to grazing land or left to shrubs. Yield reduction due to soil erosion may range from2-40% with a mean loss of 8.2%. If accelerated erosion continues unabated, yield reduction by 2020 may reach 16.7% (lal, 1995). Recent studies indicated that the storms were 34 and 51 incidents for2002 and 2003 in Al-Fashir (Ayoub,1999). Soil particles analysis showed that, soil samples of Khartoum State were medium textured including 20 sandy clay loam and 16 sandy loam, while North Darfur State were coarse textured

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soil including15 sand,10 loamy sand and 6 sandy loam. For the wind erodibility indices, the range for Khartoum State and North Darfur State samples range from 0.0 to 259.3 and from 25 to 695 ton/ha, respectively (Medani, 2004)
Farmers practiced cultivations of millet, sorghum, sesame and groundnuts during the rainy season and they keep livestock. The dominant grass species in the range land are panicum furgidum and Aristida hordeocea. The northern parts of the state is poor in forage trees and in the dry season supports only relatively small number of animals. Trees such as Acacia ehrenbergions , Salvadosa persidea and Acacia raddiana are very rare, scattered and they are small in size. Dry season range land: good grazing is found and cover large areas sometimes late until March. The common species are Commiphara Africa, Aristida mutabililis and Aristida funiculate.
2- Land Degradation and desertification
Desertification is combinations of drought processes which result in more or less irreversible of the vegetation cover leading to the extension of new desert landscapes to areas which were formally not desert. The increasing destruction has influence through reduction of food production and loss of genetic resources of plants and animals. Desertification can be defined as: "the land degradation in arid and semi- arid and dry sub-humid areas resulting from various factors including human activities and climatically variations (UNCCD, 2001) ".

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Land degradation is the reduction of the current and potential productive capacity of the land. Vegetation degradation is the quantitative and /or qualitative reduction of the vegetation cover resulting from various factors including human induced activities and severe prolonged droughts under poor land resource management Mustafa,2007). Despite adverse and fragile initial conditions of most tropical soils, human activities significantly contribute to land degradation, either directly or indirectly.
2-1 Causes of desertification
a--Climatic variation
Droughts have frequently happened as a natural disaster and unavoidable phenomena in wide areas of the world. The rural poor in dry areas will suffer the most from this phenomenon and will require a range of coping strategies to help them adapt to changing climates. Drought is an insidious hazard of nature and originates from a deficiency of precipitation over an extended period of time, usually one season or more. During the period 1961-2000, droughts of varying in severity occurred in the state. This period witnessed two widespread droughts during 1967-1973 and1980-1984. The same period witnessed a series of droughts during the years1987, 1989 and1990.
In the semi-arid zone of sub-Saharan Africa, especially the rural savannah zone, poverty and food insecurity are interlinked and widespread and strongly linked to the natural resources endowment (water, soils and vegetation). Land and water degradation, overgrazing

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and slash burn agricultural production practices have led to significant environment degradation and food shortages. The capacity of most areas to combat desertification is limited, due to the widespread poverty, recurring droughts, inequitable land distribution and the dependence on rain-fed agricultural (Mc Cartly et al., 2001). In comparison to all other regions of the world, the agricultural productivity per unit of water (“crop per drop " ) in the semi-arid zones is the lowest worldwide (Rockst-on, et al., 2004). The increasing vulnerability of societies and ecosystems leads to a downward spiral of ecological and social degradation and consequently to an increase to disasters(Table1,Fig.1).
Table1. Long-term rainfall reduction in Darfur
Location
Average annual rainfall (mm)
Average annual rainfall (mm)
Reduction (-)
(mm)
%
1946-1975
1976-2005
AlFashir
272.4
178.9
93.5
-34
Nyala
448.7
376.5
72.2
-16
AlGeneina
564.2
427.7
136.5
-24

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Fig 1. Distribution of annual rainfall (10 years) in Al-Fashir during the period 1946-2000
A climate study was conducted in western Sudan using rainfall and temperature data for the period 1961 – 1990 and modeled to predict changes in temperature and rainfall from the baseline to the years 2030 and 2060. The climate model results indicated a 0.5 to 1.5 C rise in the average annual temperature and an approximate 5% drop in rainfall. The findings were then used to project the scale of potential changes in crop yields for sorghum, millet and gum Arabic. Sorghum production will drop by 70% from 495 Kg to 150 Kg/hectare. The model which focused on changes in the growing season, predicted that in the state, the growing seasons would be shorter and the percentage of failed harvests would increase.
0501001502002503003501946-19551956-19651966-19751976-19851986-19951996-2005 Rainfall (mm) years

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b- Human activities
i- Population growth
North Darfur State had a population of 1.3, 2.1 million according to 1993 and 2008 census, respectively. In Darfur region statistics indicated a regional population linear growth rate of 12% per annum, from 3 persons /km2 in 1956 to 18 persons / km2 in 2003 ( Fadul, 2004).The displacement of the people from the north Darfur due to desertification (Table 2). The population is concentrated in a belt between 11◦ and 14◦ N. North of this belt, towards 16◦ N the decreasing annual rainfall reduces the importance of agricultural activities and nomadic pastoralism. The population consists of different ethnic groups; some are specialized in crop cultivation, others in cattle rearing and camel herders.
Table 2. Population growth in Darfur region during the period 1956-2003
Year
Population (1000)
Population density (person/ km2
1956
1080
3
1973
1340
4
1983
3500
10
1993
5600
15
2003
6480
18
ii - Crop cultivation
People practice cultivation of sorghum, millet, sesame and groundnuts during the rainy season and they keep livestock.

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Traditionally farmers practiced a type of rotating fallow agriculture which left portion of the land with some ground cover. There is an increase in encroachment of cultivation into pastoral area. Subsistence needs are considered to be about 250 kg of cereals/person/year. Decrease in yields and increase in population that mean more land should be cultivated. Cultivation of crops reached areas receiving 150 mm and cop rotation is reduced resulting in decrease of soil fertility and yields (Tble3, 4).
Pearl millet (Pennisetum glacum (L.) R.Br) is one of the most drought resistant grains and appears to be more tolerant of sandy and acidic soils. It is deep rooted and can use residual nitrogen, phosphorus and potassium. Pearl millet needs a cultivation period of about 100 days and seven favorably rainfalls. The border of relatively dense pearl millet cultivation fields about 250 mm isohyets. This border lies about 200 km north of the area of sufficient humidity for cultivation. On sandy soil 500 mm isohyets seem to be an appropriate border while on the clayey soil the 600 mm isohyets is more reasonable (Ibrahim, 1986). For pearl millet cultivation, the peasant cuts down all the trees and clears the land completely of all weeds , often uses fire killing most trees and seedlings and grasses to secure every drop of water for the millet plants. Repeating these practices leads to the ultimate destruction of the natural vegetation cover, which enhances the deflation of the top soil. People consume large amount of wood for fuel, construction, tools and fencing. Expanding population and extensive rain-fed cultivation combined to bring under cultivation

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more arable land in the state. A simulation of cropping boundaries for the year 2050 implies that large areas at the margins of current arable lands will no longer be suitable for cropping (Thornton,et al., 2002). It was reported that about 65% of sub-Saharan Africa's populations in rural areas are mostly dependent on rain–fed agriculture. Their need to improve food security and livelihoods become a matter of utmost importance and urgency. The current level of dependency on irrigated land is very low (less than 2% of the cultivated land), therefore rain- fed agriculture increasingly plays central role in sustaining rural livelihoods and meeting food requirement.
Table 3.Millet production in North Darfur State during 1970 – 2005
Year
Area cultivated (1000 fed)
Area harvested
(1000 fed)
Product
(1000 MTS)
Yield
(kg/fed)
year
Area cultivated (1000 fed)
Area harvested
(1000 fed)
Product
(1000 MTS)
Yield
(kg/fed)
1970/ 71
480
360
62
583
1986/ 87
1262
757
35
171
1971/ 72
676
345
54
511
1987/ 88
925
555
15
132
1972/ 73
678
366
51
139
1988/ 89
951
713
45
215
1973/ 74
633
342
32
267
1989/ 90
905
516
12
95
1974/ 75
631
473
58
362
1990/ 91
559
318
13
41
1975/ 76
944
510
51
325
1991/ 92
1290
662
58
88
1976/ 77
845
507
53
387
1992/ 93
1548
1032
82
215
1977/ 78
1072
643
60
93
1993/ 94
1720
542
36
66

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1978/ 79
1065
639
65
417
1994/ 95
2400
1800
180
100
1979/ 80
944
538
41
303
1995/ 96
2074
1058
16
15
1980/ 81
1003
602
66
445
1996/ 97
1720
528
23
44
1981/ 82
1003
602
73
384
1997/ 98
2014
1037
75
72
1982/ 83
1118
559
29
52
1998/ 99
2200
1861
251
135
1983/ 84
2110
654
46
70
1999/ 00
1493
979
80
82
1984/ 85
1748
542
25
46
03/2004
2230
1050
83
79
1985/ 86
1218
731
48
227
04/2005
2380
1322
79
60
Source: Ministry of Agriculture and forestry- Khartoum – Sudan (2002)
Table 3.Sorghum production in North Darfur State during 1974 – 1990
Year
Area cultivated (1000 fed)
Product
(1000 MTS)
Yield
(kg/fed)
Year
Area cultivated (1000 fed)
Product
(1000 MTS)
Yield
(kg/fed)
1973/74
228
7
236
1982/83
65
10
154
1974/75
50
13
250
1983/84
42
1
30
1975/76
55
12
212
1984/85
45
1
22
1976/77
43
5
103
1985/86
115
21
180
1977/78
52
7
134
1986/87
100
7
70
1978/79
52
10
192
1987/88
175
5
30
1979/80
41
2
46
1988/89
210
37
175
1980/81
50
7
140
1989/90
200
8
40
1981/82
55
12
218
-
-
-
-
Source: Ministry of Agriculture and forestry- Khartoum – Sudan (2002)

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iii - Overgrazing
Livestock rearing is categorized into three types, pure nomadic based largely on the herding of camels, sheep and goats, semi- nomadic combing the herding of cattle and some sheep with a form of cultivation in the seasonal wadis and sedentary system, where cattle and small livestock are reared in close proximity to village. Seasonal migration is often practiced by nomads and they face the problem of overgrazing and the excessive use of water holes. The result is that the surrounding grazing is destroyed and the grazing areas become bushy. Methods of estimating livestock numbers showed there are large numbers of animals in the state. Pastoral cattle herds show low milk productivity and low slaughter off take as compared with other herds and these breads are highly suitable for extreme climate. Marketing of the cattle faces great difficulties including long transport distances, price and processing.
iv- Deforestation
Forests and trees are the main sources of energy and provide timber for roofing and building. The extensive benefits derived from forests include grazing, hunting, shade, forest foods in the form of tree leaves, wild fruits, nuts, tubers and herbs, tree bark for purposes, and non- wood products such as honey and gum Arabic. This valuable resource is threatened by deforestation driven principally by energy needs and clearing land for cultivation. The types of forests and vegetation found in state are: desert and semi- desert trees and shrubs

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and low rainfall woodland savannah. Most trees in North Darfur State grow in open to semi –closed woodland with numerous grasses and shrubs. Desert vegetation is limited to xerophytes shrubs such as Acacia ehrenbergion, Salvadosa preside, Acacia raddiana ,Commipharea fricana , Aristida mutabililis and Aristida funiculate.
Deforestation is an overall and effectively permanent reduction in the extent of tree cover. The removal of trees has a range of very negative impacts, including increased land and water resource degradation, and the loss of the livelihoods from forest ecosystem service. There are several causes of deforestation: fuel wood and charcoal extraction; mechanized agriculture; traditional rain-fed and shifting cultivation; drought and climate change; over browsing and fires and conflict impacts. The reductions in rangelands has caused problems for the pastoralist mobility but have kept their annual herd migrations to well- defined routes. Their general pattern is to move from north and south to optimize grazing conditions and minimizes pest problems. Similar pattern of migration, though over shorter distances, occurs in the hilly regions, where village’s areas are grazed mainly in the dry season and high rangeland mainly in the wet season. The major reduction in the amount, quality and accessibility of grazing land is considered to be a root cause of conflict between pastoralist and the village farmers.
c- Climate change
African dry lands are affected by climate change. It was confirmed that most published climate change scenarios indicate temperature

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increases for most of Africa, while expected rainfall trends vary (IPCC, 2007). There is a general consensus that climate variability will increase leading to an increase in drought and floods and to growing uncertainty about the onset of the rainy season. Climate change thus affects the hydrological cycle, water resources, agriculture and ecosystem performance and services.
The climate variability in Sub-Sahara Africa has shown a marked decline in rainfall leading to decrease in discharge of some watercourses (Nissae et al . 2004) .In the second half of the last century, mean annual temperatures in Africa rose approximately half a centigrade with some areas worming faster than others . This gradual heating means more warm spells (days) and fewer cold days across the continent. IPCC (2007) reported that a warming in Africa may be higher than the global average and that may be persisting throughout all seasons. Further, it was reported that annual mean surface temperatures are expected to increase between 3 -4 oC by 2009 which is 1.5 times the average global temperatures rises. On regional variations it was concluded that warming is likely to be greatest over the interior of the semi-arid margins of the Sahara and central southern Africa. In East Africa increasing temperatures due to the climate change will increase rainfall by 5 -20% from December to February, and decrease rainfall by5–10% from June to August by 2050 and Al-Fashir meteorological station showed the same trend. The long- term (30 years) average precipitation for Al–Fashir has declined from 300 mm per annum to approximately 200 mm during

18. 91
the period1961-2000, while before 1953 the annual rainfall exceeded 400 mm (Table 1, Fig1).
2-2- Socioeconomic impact
The reduction in rainfall has turned million of hectares of already marginal semi- desert grazing land into desert. The impact of climate change is considered to be directly related to the conflict in the region and desertification added significantly to the stress on the livelihoods. Fighting in Darfur has occurred intermittently for at least thirty years. Until 2003, it was mostly confined to series of tribal and local conflicts. The ongoing conflict is characterized by a ' scorched earth' campaign carried out by militias over large areas, resulting in a significant number of displacements of people into camps for protection, food and water and over two million people are displaced since the beginning of the war(UNEP/FAO/ICRAF ,2006).
3-Combating desertification
Desertification is the destruction of the biological potential of the land and leads to deserts like conditions. The most identical causes are human mismanagement of soil, water, energy. Land degradation occurs due to overgrazing, farming marginal lands, population growth and drought. Natural arid ecosystems are able to withstand prolonged drought without significant loss and when rains return, such community’s spring back into vigorous function.
Desertification/degradation reduce the productivity of the land, which are exacerbated through non-sustainable use. Combating

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desertification aims to restore this loss through sustainable land use systems that increase soil organic matter, prevent soil erosion, improve soil structure, increase infiltration, decrease rain drop impact, decrease runoff, promote salt-leaching and protect soil from the accumulation of toxic substances. The general projects include promoting public environmental awareness, policies, legislation and land tenure, community services e.g. marketing, monitoring and evaluation, food production and research and technology transfer. Specific projects include reforestation, sand dune fixation, restocking of gum arabic trees,firelines.village perimeters, increasing food productivity, rainwater harvesting techniques and wildlife reserve (Mustafa, 2008).
The range and water should be effectively owned by definite groups. The range must be used in a rotational pattern using different grazing techniques and impartation off by fire breaks and marketing facilities should be provided. From estimation it was found that fires usually remove 80 million tons of forage from dry savannah range resources equivalent to 9 months diet of 25 million cattle. Shortage of forage can be balanced especially in the low land depressions and the natural water spreading areas where production of forage exceeds the livestock consumption capacity for dry periods(Glantz, 1977).
Water management includes water harvesting techniques e.g. natural impervious surface, land alternation, chemical soil treatment, utilization of periodic stream flows for water spreading, maintaining

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water where it falls (in situ),modifying the vegetation on water shed areas to improve yields, erosion and evaporation control(Abdalla,2008). The management of the state is to control population growth, emigration and proper land use. The guides for development should be based on a realistic acceptance of the ecological factors: low rainfall, unpredictable recurrence of periodic drought, uncertain and irregular production, low potential per unit land area and unstable ecosystems (Goodall, et al.1979).
4-Discussion
Desertification results in the creep of desert like conditions into areas where they should not climatologically exist. It is due to the increasing pressure of man and his animals in unstable semi-arid regions. Desertification is discontinuous whereas it may be more or less halted during a series of heavy rainy seasons.
Biological recovery of degraded ecosystem should include increase of biological activity, biomass, plant cover, organic matter and soil micro and macro organisms. It is also includes higher soil fertility, better water intake and lower evaporation and runoff. It attained through natural and semi-natural conditions. Natural biological improvement of ecosystems is achieved through protection from man and his animals such as fenced areas where animals not be allowed to enter. Natural ecosystems development allow to increase development of producers and then consumers which leads to production of organic matter and increases biological activity thereby improving soil structure, permeability and water intake. Natural system is slower

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when the climate is more arid and it is excellent in enclosures (Goodall,et al.1979). Semi-natural may be speeded up by artificial measures such as pitting, counter terracing, over sowing, water spreading techniques and fertilization. It also includes planting drought resistant of woody species for fuel, sand dune stabilization, wind breaks, shelter belts and reclamation of saline and alkaline land.
Conclusion
Desertification is partly manmade phenomenon aggravated by climate circumstances and any measure for stopping loss of land productivity and to increase degraded land productivity must nesserialy interfere with human behavior and land use management. Natural recovery should include increase of biological activity, biomass, plant cover, organic matter and soil micro and macro organisms. Range must be used in a rotational pattern using different grazing techniques and impartation of by fire breaks and marketing facilities should be provided. Shortage of forage can be balanced especially in the low land depressions and the natural water spreading areas where production of forage exceeds the livestock consumption capacity for dry periods.
Recommendation
It was suggested that in order to reduce desertification some steps should be taken by the government. These steps will include reducing the dependency of rural society on agricultural income, use of advanced weather forecasting tools, cultivation of resistance crop varieties, crop diversification and adaptation of new water harvesting

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techniques especially use of supplementary irrigation systems. One should differentiate between true climate deserts and the man made deserts which occur in arid regions.
The strategy for the countries at risk is to use their natural resources in a sustainable manner and to check population growth. These should be on increase in projects concern with conservation of ecosystems such as planting shelter belts on huge scale, range management and water management (Goodall, et al.1979). Maximum advantage can be gained by control of livestock levels, rain-fed cultivation and soil cover is desirable to conserve soil nutrients which enable the surface plant cover to spring back into a high productivity.

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