This study argues that by mobilising ‘social resources’, communities in water-scarce, semi-arid areas can not only successfully sustain a livelihood, but they can also play an important role in the water budget of their semi-arid regions. The pastoralist communities in the Darfur region of west Sudan utilise the limited volumes of green – root-zone – water in the soil to rear livestock. They have for centuries developed and adopted a very adaptive management system that has enabled them to utilise the green water of the Nile Basin. The embedded green water in livestock totals more than Sudan's annual share – 18.5 km3 – of the Nile River flow allocated to it by the 1959 Nile Waters Agreement. This study has revealed that this embedded ‘virtual water’ amounts to 37.6 km3. Results show that this silent, unrecognised, green water has been providing a solution to the water requirements of the Nile economies. It has been suggested that if Western Sudan's livestock were to be produced using fresh/blue water from the Nile, the national water balance of the Sudan would be very seriously impacted and the economy would be much less secure than it has been for the past half century.

Introduction

The purpose of this study is to highlight the role of green water – otherwise known as soil water or effective rainfall – in Darfur in the Sudan. It will be argued that the green water of such regions are vast and in volume exceed the more evident blue water resources to which much attention and investment has been devoted. The adaptive practices of pastoralists has enabled the invisible green water to play an essential role in the livelihoods of local populations as well as have major impacts on national and regional economies. The volume of ‘virtual’ water embedded in livestock that ‘flows’ from Western Sudan is calculated. Virtual water is a term coined by Allan (2001). It referred originally to the water imbedded in food and other products, required to produce it.

Geography of Darfur

Darfur is the western region of the Sudan, and covers 549,000 square kilometres, an area the size of France. The climate of the region ranges from the completely arid Sahara desert in the north to the dense savanna woodland of the south, where rainfall may reach 1,000 millimetres per annum. The region is extremely water scarce in the north and is seasonally water scarce in the south. However, the extent of the area is so vast that overall it has substantial soil water resources, making the region more water abundant, albeit counter-intuitively, than the riverain tracts that play such a prominent role in the minds and priorities of the policy-makers in the country.

Western Sudan: water management efficiency in practice

Water Management options for a basin can be influenced by the water resources in the region and by waters outside and peripheral to the watershed itself. It will be argued that – despite being dry, with very little fresh surface or ground water and distant to the Nile River – Western Sudan has, counter-intuitively, been playing a very important role in the water balance of the Sudan and in the Nile River Basin as a whole. Its soil water supports very large populations of livestock, and the region produces vast quantities of meat products for consumption in other parts of the Basin – mainly in the Sudan and Egypt. Exports of livestock in normal years are also substantial. Such production would not be possible if it relied on the Sudan's share of the River Nile.

The Sudan is the only country in the Arab Region with a considerable surplus of livestock production. This surplus can meet some of the huge demand of the Middle East and the Arab World.

This study shows that solutions to water resource management problems are not only provided by the Nile River for the communities living in the vicinity of the river. It will also be shown that it is unhelpful to ignore these hidden water resources (green water) of Western Sudan. Both water resource professionals and policy-makers ignore them or are unaware of their significance in the water budget of the Sudan. In the Nile Basin of the Sudan, water use for livestock production is also largely ignored by decision-makers, despite the fact that the production of livestock is the single largest water consumer.

Livestock everywhere are a major water consumer: the production of one tonne of meat requires much more water than the production of one tonne of crops. Livestock in economies such as that of the Sudan utilise soil (or green) water. Green water is known as effective rainfall by hydrologists and agronomists (Allan, 2002). Soil profiles in semi-arid and savanna regions, such as Western Sudan, unlike in temperate and humid regions, have low soil water holding capacities. However, by mobilising the necessary ‘social adaptive capacity’ (Ohlsson, 1999) the people of Darfur and Kordofan have, for centuries, been coping with such water scarcity and at the same time have been producing surplus livestock products. The scarce soil waters in Western Sudan – many hundreds of kilometres from the Nile valley – have produced livestock for consumption in populous cities along the Nile valley in the Sudan and Egypt. Accordingly, it can be stated that if Western Sudan's livestock were to be produced using fresh water from the Nile, the national water balance of the Sudan would be very seriously impacted and the economy would be much less secure than it has been for the past half century.

The mobility of the herders of Darfur and Kordofan, and their capacity to adapt to their environment is a very effective coping strategy that ensures their livelihoods, and enables them to make a significant contribution to the national economy. Livestock contributed more than 28% of the national gross domestic product in 1998. The Sudan is the only country in the region with a considerable surplus of livestock production. Darfur and Kordofan are the biggest livestock producers in the Sudan and the Nile Basin.

To ‘adapt’ to water scarcity in the region, people in Western Sudan use the little existing soil water for the livestock sector and for subsistence agriculture. To compensate for the limited soil water, and hence low vegetation cover in the pasture lands, livestock are moved north-south following the rainfall. It is the ‘adaptive capacity’ of the transhumant herders that has enabled them to cope with water scarcity and make a major contribution to the national economy.

Animals can be flexible in their consumption and are able to take advantage of the seasonal changes in the carrying capacity of the rangelands of Western Sudan. They are regarded as ‘assets on the hoof’, to be moved or sold at different stages of growth in times of environmental or political stress. They also provide economic services other than food, such as transport and labour. For pastoralist communities, the herd is more than just a livelihood; it is also the symbol of their wealth, survival, and identity.

The rains in the region decrease northwards, approaching zero in the desert in the north. These low rainfall levels provide little soil water and sustain low to medium density vegetation cover in the rainfed pastures. To compensate for the low rainfall levels, and hence the low soil water content in the region, herders move much of their livestock to follow the seasonal rains. In the wet season, herders move their livestock northward where rainfall is less and the soil water is just enough to support the livestock. By so doing, they avoid the harmful insects and muddy conditions that encourage diseases, such as hoof disease, among livestock in the seasonally wet southern areas. In the dry season – November to April – herders move their livestock back to southern areas. Every year, herders cover hundreds of kilometres seeking natural pastures. Figure 1 shows the main routes taken by livestock in their seasonal annual migration; they are shown as green lines (please refer to the online version of this paper to see this figure in colour: http://dx.doi.org/10.2166/wp.2015.130). As part of their adaptive strategy herders use bulls and cows for transport, and to carry luggage (see Figure 2).
Fig. 2.

Pastoralists in Darfur use bulls for transport and to carry necessary luggage (beds, etc.) during the migration seasons. Source: Wikipedia (2008) Messiria tribe. Accessible at: https://en.wikipedia.org/wiki/Messiria_tribe.

Fig. 2.

Pastoralists in Darfur use bulls for transport and to carry necessary luggage (beds, etc.) during the migration seasons. Source: Wikipedia (2008) Messiria tribe. Accessible at: https://en.wikipedia.org/wiki/Messiria_tribe.

Animal wealth in Western Sudan

Western Sudan (Darfur and Kordofan) is the most important livestock production region in the former Sudan, as well as in the Nile Basin countries. Estimates of livestock populations in the period 1999–2001 for Western, Northern, and Southern Sudan are shown in Table 1.

Table 1.

Livestock production in head in Western, Northern and Southern Sudan 1999–2001.

Region Cattle Sheep Goats Camels 
1999 
 Western Sudan 13,390,814 37 18,789,957 42 13,514,352 36 1,833,923 61 
 Northern Sudan 11,783,871 33 14,877,093 33 12,658,005 34 1,197,077 76 
 Southern Sudan 10,650,316 30 11,134,950 25 11,173,643 30 
 Sudan 35,825,001 100 44,802,000 100 37,346,000 100 3,031,000 100 
2000 
 Western Sudan 13,864,772 34 19,332,241 42 13,949,317 36 1,880,512 61 
 Northern Sudan 15,561,953 38 15,306,451 33 13,065,409 34 1,227,488 39 
 Southern Sudan 11,027,275 27 11,456,308 25 11,533,274 30 
 Sudan 40,454,000 100 46,095,000 100 38,548,000 100 3,108,000 100 
2001 
 Western Sudan 14,325,886 37 19,729,834 42 14,462,624 36 1,938,135 61 
 Northern Sudan 12,608,928 33 15,622,980 33 13,543,728 34 1,264,864 39 
 Southern Sudan 11,390,193 30 11,690,186 25 11,945,650 30 
 Sudan 38,325,007 100 47,043,000 100 39,952,002 100 3,202,999 100 
Region Cattle Sheep Goats Camels 
1999 
 Western Sudan 13,390,814 37 18,789,957 42 13,514,352 36 1,833,923 61 
 Northern Sudan 11,783,871 33 14,877,093 33 12,658,005 34 1,197,077 76 
 Southern Sudan 10,650,316 30 11,134,950 25 11,173,643 30 
 Sudan 35,825,001 100 44,802,000 100 37,346,000 100 3,031,000 100 
2000 
 Western Sudan 13,864,772 34 19,332,241 42 13,949,317 36 1,880,512 61 
 Northern Sudan 15,561,953 38 15,306,451 33 13,065,409 34 1,227,488 39 
 Southern Sudan 11,027,275 27 11,456,308 25 11,533,274 30 
 Sudan 40,454,000 100 46,095,000 100 38,548,000 100 3,108,000 100 
2001 
 Western Sudan 14,325,886 37 19,729,834 42 14,462,624 36 1,938,135 61 
 Northern Sudan 12,608,928 33 15,622,980 33 13,543,728 34 1,264,864 39 
 Southern Sudan 11,390,193 30 11,690,186 25 11,945,650 30 
 Sudan 38,325,007 100 47,043,000 100 39,952,002 100 3,202,999 100 

Table 1 demonstrates that on average more than a third of the cattle population, and almost half of the sheep population in the Sudan are produced in Western Sudan. The vast pasture lands of Western Sudan rely only on rainfed soil water. Cattle are the biggest water consumers of all livestock types, with high volumes of water in fodder and for drinking water consumption. A single cattle livestock unit consumes more than 20 times the water consumed by a sheep (Hunting Technical Services Limited et al., 1979).

Western Sudan's livestock, on the other hand, are generally consumed in Sudan's major cities and large population centres along the Nile valley, or are exported to Egypt and Gulf states. Cattle and sheep are reserved for sale in Nyala, and are also sent from there to Omdurman market in the capital, Khartoum.

Omdurman is the biggest livestock market in the Sudan. It is the hub of the livestock marketing system in the Sudan (Hunting Technical Services Limited & MacDonald, 1976). It is endowed with the financial and organisational facilities to operate nationally and internationally. Figure 3 shows the contribution of Western Sudan cattle to Omdurman market.
Fig. 3.

Source of cattle reaching Omdurman-Khartoum, 1974–1975. Data source:Hunting Technical Services Limited & MacDonald (1976).

Fig. 3.

Source of cattle reaching Omdurman-Khartoum, 1974–1975. Data source:Hunting Technical Services Limited & MacDonald (1976).

Figure 3 shows that 82% of the cattle are raised using the unaccounted green water in the soil profiles of Western Sudan, while 8% or more consume valuable Nile waters.

Western Sudan: virtual water in livestock

Livestock products contain 5 to 20 times more virtual water per kg than crop products’ (Hoekstra & Chapagain, 2003).

A study carried out by Hoekstra & Chapagain (2003) estimated the amount of virtual water contained in different types of products in different countries. Table 2 shows what Hoekstra & Chapagain (2003) estimated to be the water embedded in a live animal (m3/tonne) in the Sudan. They concede that these estimates are based on average numbers and these cannot be applied satisfactorily to all the different ecological zones and livestock types. However, these estimates were the best they could identify in the global study which they carried out.

Table 2.

Sudan's virtual water content of live animals (m3/tonne).

Live animal Beef cattle Dairy cows Swine Sheep Goats Fowls/poultry Laying hens Horses 
Water Content (m3/tonne) 13,265 187,055 6,548 6,248 5,689 13,072 65,367 5,783 
Live animal Beef cattle Dairy cows Swine Sheep Goats Fowls/poultry Laying hens Horses 
Water Content (m3/tonne) 13,265 187,055 6,548 6,248 5,689 13,072 65,367 5,783 

Virtual water content in Western Sudan's live cattle

To assess the amount of virtual water in live animals in Western Sudan, results from other studies carried out by professionals and experts in the field, are used as additional inputs. For instance, Hoekstra & Chapagain's (2003) calculations of virtual water content of live cattle in the Sudan are used. Also, the average weight of cattle has been taken from different studies and sources (Hunting Technical Services Limited & MacDonald, 1976; Hunting Technical Services Limited et al., 1979; Mahir, 2001; Elgaili, 2006).

An assumption has been made regarding the average weight of cattle. The average cattle weight quoted in the studies mentioned above ranges between 240 and 300 kg with an average of 270 kg for a fully-grown cattle unit. To account for calves and cattle which are not fully grown in the calculations, an average calf weight of 100 kg is used. The average cattle unit weight is calculated as: (270 + 100)/2 = 185 kg. This assumes that there are an equal number of calves and fully-grown cattle.

From Table 1 the average cattle production in Western Sudan (1999–2001) is estimated to have been 13,860,491 head.

The average weight of live cattle in the Sudan is: 185 kg (0.185 tonne) 
formula
Therefore: 
formula
 
formula
 
formula
 
formula

The calculations of Hoekstra & Chapagain (2003) assume the composition/consumption of irrigated fodder crops such as wheat, sorghum, oats, barley, etc. However, livestock in Western Sudan rely mainly on natural pastures. In these circumstances much less water is involved in the production of livestock.

The numbers estimated in the above calculations imply that if the cattle of Western Sudan were to be produced by irrigation from the Nile fresh waters, more than 30 km3 of water would be required every year. Allan (2001, 2013) has pointed out that the virtual water ‘content’ in a commodity can be estimated by the producer and by the importer/consumer. The virtual water is also valued differently by the producer and by the importer/consumer. In the case of livestock production in Western Sudan it is more efficient in terms of returns to water to produce livestock on the pastures of Darfur and Kordofan than with fodder grown on the irrigated tracts in the Nile lowlands (Allan, 2007; Zeitoun et al., 2010).

The figures calculated for the virtual water content of the cattle production in Darfur are based on the consumption of irrigated fodder. This approach is consistent with the intent of this study, which is to identify the amount of ‘surface/blue’ Nile water that is required to produce these livestock.

Western Sudan's live sheep population and its virtual water content

Using the same approach as for cattle the virtual water content for sheep is calculated as follows: 
formula
 
formula
 
formula
 
formula
 
formula
As for goats, the virtual water content, using the model, is found to be 1.2 km3.

Therefore, the total virtual water content in livestock (cattle, sheep and goats) in Western Sudan is 37.6 km3.

This volume of virtual water embedded in livestock in Western Sudan is very significant. It is more than twice the Sudan's 1959 share of the Nile water of 18.5 km3, and just less than 45% of the total Nile flow at Aswan of 84 km3. It is this vast quantity of soil water that maintains the Sudan's water balance. Green water in the soil profiles is not taken into account officially, not least because it is not easily measurable. The livestock production and trade associated with the vegetation derived from soil water plays a very significant role in the economy of the Sudan when normal levels of conflict are in evidence (Morton, 2005).

Water required to fatten livestock along the Nile valley

To assess and quantify the importance of Western Sudan's huge livestock production to the Nile water balance, evidence of livestock water consumption along the Nile will now be examined. Unfortunately recent data and research are lacking and it is necessary to use results from a study published in 1979. It is suggested that these results are still valid as no significant changes in livestock rearing practices, nor in irrigation fodder production, nor in the pastures and crops themselves, have taken place since the 1979 study was carried out.

The study was a joint study carried out by a group of consulting companies, headed by Hunting Technical Services. The study examined the feasibility of commercial livestock enterprises that used Nile water to irrigate fodder on production schemes. Although the objective of the schemes was to irrigate fodder crops to feed cattle and sheep so as to fatten them for slaughter, the study also provided a review of livestock water consumption along the Nile. In the study a model of hypothetical schemes in Wad Medani, 100 km south of Khartoum, based on proposals that had already been put forward, was developed. It was proposed to feed herds of cattle and sheep for 100 days to fatten them for sale and export.

Crop water requirements for irrigated fodder were calculated for 10 years between 1962 and 1973. The calculations were based on the main fodder crops grown in the region: first, lucerne, which requires water all year around; second, dura, which requires water from July to early November; third, abu Sabien, which requires water from February to November; and fourth, maize, which requires water from October to March. The average annual water requirement for 10,000 feddans was estimated as 48.51 million cubic metres with a range of 42.11 to 55.57 million cubic metres. It was estimated that the area could support 10,400 cattle and 160,000 sheep. That is equivalent to 18,400 cattle in terms of water consumption (taking the 1:20 cattle/sheep consumption ratio), or 368,000 sheep.

These estimates suggest that the amount of fresh Nile water required to fatten 1 head of cattle in 100 days is: 48,510,000 (cubic metres)/18,400 = 2,636.4 cubic metres.

The equivalent amount of water for 1 sheep is: 2,636.4/20 = 131.8 cubic metres.

In Table 1 the average number of cattle in Western Sudan was 13,860,491 in 1999–2001.

The average number of sheep in Western Sudan was 19,284,011.

These estimates imply that the water required to feed the cattle of Western Sudan to fatten them for just 100 days is: 
formula
That required to feed the sheep of Western Sudan to fatten them for just 100 days is: 
formula
Based on the 1979 study by Hunting Technical Services Limited et al., the total amount of water estimated to be needed to fatten the cattle and sheep of Western Sudan for 100 days is 39 km3.

These calculations confirm the high levels of fresh water that would be required to raise livestock in the Nile region, and the great significance of soil or green water from Western Sudan embedded in the livestock production and exports of the region.

Taddese's virtual water calculation

The results obtained in this study carried out on the virtual water content of livestock can be compared with the only other known study addressing this topic in the Nile Basin. This study was carried out by Taddese et al. (2005) on Ethiopian livestock by researchers at the International Livestock Research Institute. The study uses 2002 livestock data, and the results of Taddese's study are shown in Table 3.

Table 3.

Virtual water content (km3) per livestock produced in the Nile River Basin countries, 2002.

Country Dairy milk Beef Poultry meat Pig meat Eggs 
Burundi 0.036 1.093 0.01 0.017 0.01 
Congo DR 0.01 1.579 0.035 0.138 0.024 
Egypt 3.802 30.615 1.078 0.01 0.757 
Eritrea 0.099 2.065 0.004 – 0.007 
Ethiopia 1.847 36.204 0.146 0.003 0.262 
Kenya 3.427 35.232 0.106 0.041 0.21 
Rwanda 0.162 2.308 0.002 0.01 0.007 
Tanzania 1.361 27.335 0.081 0.045 0.217 
The Sudan 5.849 44.587 0.059 – 0.158 
Uganda 0.973 11.785 0.081 0.268 0.069 
Country Dairy milk Beef Poultry meat Pig meat Eggs 
Burundi 0.036 1.093 0.01 0.017 0.01 
Congo DR 0.01 1.579 0.035 0.138 0.024 
Egypt 3.802 30.615 1.078 0.01 0.757 
Eritrea 0.099 2.065 0.004 – 0.007 
Ethiopia 1.847 36.204 0.146 0.003 0.262 
Kenya 3.427 35.232 0.106 0.041 0.21 
Rwanda 0.162 2.308 0.002 0.01 0.007 
Tanzania 1.361 27.335 0.081 0.045 0.217 
The Sudan 5.849 44.587 0.059 – 0.158 
Uganda 0.973 11.785 0.081 0.268 0.069 

In Table 3, Taddese et al. (2005) estimate the virtual water embedded in beef – not live cattle – to be 44 km3/yr for the whole of the Sudan. This estimation is in the range of the estimates of virtual water in cattle calculated for Darfur and Western Sudan earlier in this study. The total virtual water in live cattle in the Sudan, according to the figures and methodology used in this study, totalled 93 km3/yr (for about 38 million cattle on average). If it is estimated that meat constitutes about 45% of the live cattle (Mahir, 2001), then the virtual water in beef calculated by the method used in this study would be about 42 km3/yr. This estimate is consistent with the Taddese metrics considering the unavoidable imprecision of the methodologies.

The Sudan: virtual water embedded in red meat consumed locally

The amount of red meat consumed locally in the Sudan is increasing every year. This increase in consumption is attributed to population increase, and to changing patterns of life. The urbanisation of rural areas and the ever increasing migration to urban centres along the Nile has resulted in changing diets and consumption patterns. Higher incomes and access to electricity and refrigerators for storing meat are some of the many factors that have enabled those living in the cities to consume much more meat than people in the rural areas. This increase in consumption requires increased levels of livestock production, which puts more pressure on the water resources of the country. Table 4 and Figure 4 show trends in red meat consumption in the Sudan.
Table 4.

Red meat consumption in the Sudan in tonnes (2000–2004).

Year Cattle Sheep Goats Camel Total 
2000 653,000 138,000 115,000 19,000 930,000 
2001 701,000 142,000 115,000 19,000 977,000 
2002 746,000 154,000 116,000 19,000 1,035,000 
2003 858,000 222,000 128,000 46,000 1,254,000 
2004 860,000 225,000 129,000 35,000 1,249,000 
Year Cattle Sheep Goats Camel Total 
2000 653,000 138,000 115,000 19,000 930,000 
2001 701,000 142,000 115,000 19,000 977,000 
2002 746,000 154,000 116,000 19,000 1,035,000 
2003 858,000 222,000 128,000 46,000 1,254,000 
2004 860,000 225,000 129,000 35,000 1,249,000 
Fig. 4.

Total red meat consumption in the Sudan (×1000 tonne), 2000–2004.

Fig. 4.

Total red meat consumption in the Sudan (×1000 tonne), 2000–2004.

To calculate the amount of virtual water in red meat consumed in the Sudan, the 2004 statistics in Table 4 are used. The live weight of the cattle consumed is:

860,000 × (100/45) = 1,911,111 tonnes (as meat forms 45% of the animal weight) (Mahir, 2001).

Therefore the total virtual water in the cattle slaughtered for local use is: 
formula

That is 25.4 km3/yr.

For the sheep consumed locally, the total water is calculated as follows: 
formula
The total water used to produce livestock for local consumption in the Sudan is 28.5 km3 per year, which is more than the Sudan's Nile water share of 18.5 km3 per year.

Results obtained from this calculation send a strong message to all Nile Basin riparians and the Nile Basin Initiative (NBI) officials, that livestock and its movement in the Basin are as important as crop production in terms of water consumption. In addition, the rapid increase in the demand for livestock will put enormous pressure on green water resources in the Nile Basin in the future.

Furthermore, the silent, unrecognised, soil water has been providing a solution to the water requirements of the Eastern Nile economies. In the Sudan, the livestock production in Darfur and Kordofan is of major strategic economic significance. Unfortunately, the use of these natural pastures, and the soil water that supports them, has been disrupted by the war in Darfur.

Conclusion

This study shows that by mobilising the necessary ‘social resources’, communities in water scarce semi-arid areas can play an important role in the water budget and economies of their regions. The case study presented here of the Darfur region of west Sudan demonstrates that pastoralist communities there utilise the limited volumes of green – root-zone – water in the soil to rear livestock. They have for centuries developed and adopted a very adaptive management system that has enabled them to utilise the green water, of the Nile Basin, as a result of the low rainfall. The embedded green water in livestock totals more than Sudan's annual share – 18.5 km3 – of the Nile River flow allocated to it by the 1959 Nile Waters Agreement. This study has revealed that this embedded ‘virtual water’ amounts to 37.6 km3.

The study has highlighted the role of green water in livestock production in the region. It has been shown that the livestock herders of Darfur in normal political circumstances mobilise a huge proportion of the water resources of the Sudan – as green water.

It has also been shown that solutions to water resource management problems are not limited to the central valley or to the vicinity of the Nile and its tributaries. It has been argued that these hidden water resources (green water) of Western Sudan are ignored. In the Nile Basin of the Sudan, water used for livestock production is also ignored by decision-makers, despite the fact that livestock are the single largest water consumers. The total water used to produce livestock for local consumption in the Sudan is very significant – 28.5 km3 per year, which is also more than the Sudan's Nile water share.

Results obtained in the study send a strong message to all Nile Basin riparians and the NBI officials, namely that livestock and its movement in the Basin is as important as crop production in terms of water consumption. In addition, the rapid increase in the demand for livestock, due to population increase, will put enormous pressure on green water resources in the Nile Basin in the future.

In the Sudan, the livestock production in Darfur is of major strategic economic significance. It has for example been suggested that if Western Sudan's livestock were to be produced using fresh water from the Nile, the national water balance of the Sudan would be very seriously impacted and the economy would be much less secure than it has been for the past half century. With no oil revenue since the secession of South Sudan, the Sudan needs to utilise all of its available resources efficiently and effectively to revive its economy. Unfortunately, politicians and policy-makers in the country have adopted policies that disrupt the use of the natural pastures, and the soil water that supports them, in launching and sustaining the war in Darfur, since 2003. The consequences of impairing the mobilisation of the very strategically significant soil water of Western Sudan are, as yet, not fully recorded. This study recommends a thorough study on the impact of the war in Darfur on the livestock production of the region.

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