35

Desertification in North Darfur State Salih Ahmedai Abdalla, Faculty of Environmental Sciences and Natural

Resources

Al-Fashir University-Sudan

عبدا هلل يصالح احمدا

جامعة الفاشر – كلية علوم البيئة و الموارد الطبيعية

التصحر في والية شمال دارفور

مستخلص البحث

شألجااءش الن الهقاا يفالاالهمناا والية االالداا وال شبهااحبالواايف اللااالشي الاالش اا واليال اا الالالالالال

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-0531ك يلالااحوالشألما باليال بج تالشحللشبيفالش ينح لالحملاالالش ا والاللااوالش اا يفالالالالال

مليحنالنيا لالالال9.0يعأل الش يك نال.المالب الإىلالشةببا عالالمبلألوالنصفال بجلالمئح لال9115

ال93لالكيلحم الملبعاليال تض عفالش يك نالكالالالوخصال كال01مالمبتح طالال9115ع مال

اااءبعالش اااألل الاال.اليش بااالالبمليااالاليرينيااالالب اااحبيلالاالوااا ب الشألي ااالاليالبلك نيااالال.ال ااانل

ال931شألبشضيالش لمليلاليميثلالش غ ش الش لئيسال ليك ناليالملألوالش تهاكالش ال الم الش غاوال

يفال لااااألشنالهااا الش ااااال/كجاااوال01يمتح اااطالإنت جيااالالش اااألل الاالش حة ااالال.الالش يااانلال/كجاااو

ماليال حجاألالالال0551-0590 لاألشناله الش اا يفالالال/كجو911.1م،اليش بيفال0595-9110

%ال91-3نت جيالالشحمل لايلالبا الالالاليما الشتتحعاعال نالالبانخا الإالالال.الإنت جيالالشحمل لايلالالالنقصالا

.الالالمليحنالالب سال01يالبقألبالش ثلييفالشحليحشنيلالالحبحش يال.الم9191-9111ه الش ا يفالم

منا البألش الالش يايفلين تال تا المنتصافالالالالالالالبأثلتالية لالد وال شبهحبالب جلا فاليش تصاالال

.المال9111ش ث نين تالم الش قلنالشت ضياليبل عيفتالبلألالذ بالمحج تالم الشجلاا فال تا العا مالالالال

م،ال9111ال-0500يبللضتالش حة لال لأل الم المحج تالشجلا فاليشجمل ع تالاللاوالش ا يفال

مال،ال0595ال-0509يوااهألتالش حة االال يبشتالجااا فالمتيف عااأليفاليش االلالشةنت اا باللاااوالالالالالالالال

30

ال0515ال-0519يبلتالذ بال ليللالم الشجلا فالشحملألي الاالش اا يفالال.المالال0510ال-0511

المال0555ماليال0551ماليشألعحشمال

اايف الش لئيياالال لتصااالالش تح ااعالاالدبشعاالالش ااألل الاالشتناا ر العليلاالالشألمااا بالألماا الش

ملو،اليعألمالإبيف عالش أليبيفالش ءبشعيالالالال031يشهل م يلاليش يتالشمتألتالد ًةال ت اللطالشألما بال

م،ال9113-ال9111لااوالش اا يفالالال%ال99وج بالش يتال قألبالحبح يالعالشأليش لعيالشجل ئلاليعا

يالشحنيالتالشتنا ر الش لعح الالالالال%ال51ي قألبالملألوالش اقألاليالشإلدش لالم المجللالمي لالش غ با تالال

لا الاا االش اتغ شتالباألم الالالالال.اليالشنلاألمتالشتلشعا الاالبلا الشتنا ر الالالال%الال31-91حبحش يال

يد ااا يفالك يااالالش غيفااا بالش لااا الاللغاااا الش نيفااا بيالينااااحتالشحليحشنااا تاليبلل ااالالش بااالال يإبااا يفال

ال.اليشجمل ع تاليشهلجليفاليالنءي الش يك نالإ يالشتن ر الشجلنحبيلالي ه الشألي لاليشحللي الش قيفليل

تك هالالش تصالالةالبألالم اليضعالعأليفالبلشمجالب لالم ليع تالش ت ج الشحلكحميال

ماليش ليباليإع يفالالبل ال اءشمالش صا االش للباياليدبشعالالش نخيالاليشإلبوا اليالش تحعيالاليالعيا الالالالالالالال

ال.الم ليع تالش تن يلالش ل ايلالشتتك مللالي ص الشتي ا

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

33

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 20

º

N and longitudes 21º 52

¯ E and 27

º 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

30

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,

39

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

31

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

35

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) ".

01

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

00

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

09

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.

0

50

100

150

200

250

300

350

1946-1955 1956-1965 1966-1975 1976-1985 1986-1995 1996-2005

Rain

fall

(m

m)

years

05

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.

00

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

03

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

cultivat

ed

(1000

fed)

Area

harvest

ed

(1000

fed)

Produ

ct

(1000

MTS)

Yield

(kg/fe

d)

year Area

cultivat

ed

(1000

fed)

Area

harvest

ed

(1000

fed)

Produ

ct

(1000

MTS)

Yield

(kg/fe

d)

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

00

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 03/20

04

2230 1050 83 79

1985/

86

1218 731 48 227 04/20

05

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)

09

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

01

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

05

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

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

90

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

99

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

95

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

90

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.

93

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