Sudan Agricultural Markets Performance under Climate Change ELGALI, M. B. 1 and MUSTAFA, R. H. 2

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1 Sudan Agrcultural Markets Performance under Clmate Change ELGALI, M. B. 1 and MUSTAFA, R. H. 2 1 Unversty of Gezra. Madan. Sudan 2 Unversty of Gezra. Madan. Sudan Corrospodance: Mohamed Babekr Elgal. Tel: , Emal: melgal@yahoo.com Abstract Prevous studes showed that clmate change undermnng the economes and prosperty of the countres wthn the Greater Horn of Afrca (GHA) and ther people. The economc performance of the Sudan, partcularly agrculture; depends on weather condtons, especally ranfall the major clmatc varable. In the last forty years; summer ranfall pattern across the country has been decreasng by 15 to 20 percent, whle temperatures have recorded an ncreasng trend. The purpose of ths paper s to examne the man agrculture markets performance under clmate change, ncludng ther supply, demand, trade and food securty varables. The study has developed a stochastc mult-market model for nne major agrcultural markets; the model comprses mportant characterstcs of agrculture n Sudan ncludng the dependency of agrcultural supply on ranfall and temperature. The markets have been smulated by calbratng supply and demand functons; the clmate scenaro smulates these markets under clmate change of decreasng ranfall and ncreasng temperatures trends. The model has ntroduced prces and ranfall as stochastc varables; t has also ncorporated natonal food securty ndcators lke self-suffcency rato and the rato of total export to food mports, whch are drectly affected by the agrculture performance. The uncertan (Stochastc) varables n the model are presented n ther cumulatve dstrbuton functons (CDF) by the help of BestFt; a software wthn program based on annual observatons from The fnal results are graphed n the form of cumulatve dstrbuton functon (CDF). The model scenaro smulatons revealed that, the mpact of the decreasng trend of ranfall and the ncreasng temperature trend would overall lead to consderable losses to markets supples and hence a deteroraton n the country s external sector and food securty stuaton. Keywords: Clmate change, Stochastc Mult-market model, Sudan 1 1. INTRODUCTION

2 Sudan populaton s around 36.2 mllon nhabtants n The country has a poltcal system wth three levels: federal, state and local. It s dvded nto 17 states and 133 dstrcts. About 70% of the populaton s rural. Agrculture s the man economc sector contrbutng 27% to the GDP and employng about 80% of the workforce (Bank of Sudan, 2015). Prmary resources are agrcultural, ncludng sorghum, mllet, wheat, maze, rce sesame, groundnuts, sunflower, cotton and tomato. The man croppng systems are rrgated farmng schemes and ran-fed farmng. Major agrcultural exports are cotton, sesame, Arabc gum and lvestock. Gran sorghum s the prncpal food crop, and wheat s grown for domestc consumpton. Table (1): GDP economc sectors share ( ) Agrculture Industry Servces Total GDP Years Share % Growth % Share % Growth % Share % Growth % Growth % The agrcultural sector share n the GDP has a declnng trend through the perod (table1), ths was attrbuted to the low nvestment n agrculture, prvatzaton polces and the growng servces sector. The man sectors of agrculture n Sudan are the rrgated sector, ran-fed mechanzed, tradtonal ran fed and lvestock sectors. The rrgated agrculture sector area s about 2 mllon hectares out of about 84 mllon hectares that are potentally arable. About 93 per cent of the rrgated area was n government projects; the remanng 7 per cent belonged to prvate owners. The area under ran fed mechanzed system covers about 6 mllon hectares n the state of Gedaref, Blue Nle, Upper Nle, Snnar and Southern Kordofan. Mechanzed farms are usually well over 420 hectares, n ths sector Land preparaton, seedng, and most threshng on these farms are mechanzed, whereas, weedng, harvestng, and some threshng are done manually by seasonal labor. The tradtonal ran-fed farmng system ncludes, nomadc, transhumant (movng wth anmals and growng short-maturty subsstence crops), and sedentary farmng system whch also ncludes a sgnfcant 2

3 number of lvestock. Lvestock ncludes cattle, sheep, goats and camels. The estmates of anmal resources are around 104 mllon heads n 2013 and contrbute to 45% of total agrculture sector GDP (BANK of SUDAN, 2014). Summer s the man rany season n Sudan; t s extendng from May to October, wth precptaton rangng between less than 50 mm n the extreme north to more than 600 mm n the extreme south. Ran fall s characterzed by sgnfcant varatons n dstrbuton as well as n tmng and locaton. Prevous studes showed that clmate change undermnng the economes and prosperty of the countres wthn the Greater Horn of Afrca (GHA) and ther people. The economc performance of the Sudan, partcularly agrculture; depends on weather condtons, especally ranfall the major clmatc varable. In the last forty years; summer ranfall pattern across the country has been decreasng by 15 to 20 percent, whle temperatures have recorded an ncreasng trend (IFAD, 2010). Temperature n mddle and eastern Sudan has recorded sgnfcant ncreases n wnter and autumn mnmum temperatures and maxmum temperatures durng the perod , where the average maxmum temperature has ncreased up to 38 C, (Ibrahm, 2015). Future projectons tll 2050 suggest that the mnmum change wll be durng February by an ncrease of 1 C, whle the maxmum change wll occur n November by an ncrease n of 3 C, whle the maxmum change wll occur n November by an ncrease n of 3 C. The mean annual change n temperature wll ncrease by 2.7 C (IFAD, 2011). Clmate change s suggested sgnfcantly mpact agrculture by ncreasng water demand; lmtng crop productvty and producton and reducng water avalablty n sectors where rrgaton s most needed. Consderable attenton has been gven to clmate change and ts mpacts. Agrculture s consdered to be one of the sectors most vulnerable to clmate change, and also represents a key sector for nternatonal trade. In low-lattude regons, where most developng countres are located, reductons of about 5 to 10 per cent n the yelds of major cereal crops are projected (UNEP and WTO, 2009). Sudan has been assessed to be at rsk from the effects of clmate change on agrculture (World Bank, 2010), the declnng agrcultural producton n Sudan s worrsome and a 3

4 real challenge for a government wth a populaton of approxmately 30 mllon to feed. The am of ths paper s to assess the mpact of clmate change on food securty and trade n Sudan. The rest of the paper s organzed as follows; the next secton presents the methodology of stochastc mult-market model wth clmate varables. Secton three dscusses research fndngs. Secton four concludes. 2. METHODOLOGY A stochastc mult-market model has been developed to smulate Sudanese man agrcultural markets and clmate change. In the model the nteracton between supply and demand functons descrbes the behavor of producers and consumers n the market. The model starts by formulatng supply and demand functons where prces, ranfall and temperature are assumed to play a major role n the model; they work as determnaton varables of supply and demand equatons for the market commodtes. Domestc prces are assumed to be lnked to world market prces whch n turn are determned by the world demand and supply. The model assumes the homogenety of the products and the perfect competton on the market. The fnal result depends on the elastctes n the model whch are taken as exogenous and constant. The supply and demand equatons are represented by soelastc (Cobb-Douglas) functons n whch the prce and ncome elastctes are constant (Krschke and Jechltschka, 2002). The supply of each commodty s assumed to be uncertan (stochastc) and represented by the quantty produced whch s functon of ts own prce and the prces of the competng commodtes n addton to ranfall and temperature as clmate elements. In the supply functon, quanttes, prces ranfall and temperature are consdered as stochastc varables and represented n the model by ther dstrbutonal functonal form. On the other hand, the demand (consumpton) quantty of a commodty s set to depend on ts own prce, the prces of close consumpton substtutes or complementary commodtes and the consumer per capta ncome. Demand quanttes and prces are also calculated n ther dstrbutonal functonal form. 2.1 The Supply Equatons In the model there are nne major commodtes. The supply of each s assumed to be uncertan and represented by the quantty produced whch s functon of ts own prce and the prces of the competng commodtes n addton to ranfall and temperature. 4

5 Quanttes, prces, ranfall and temperature are consdered as uncertan varables. The product supply equatons represented as follows: q s c * ( p s j j s j r k ) * ( p ) *( R ) *( F ),, j 1,..., 9 Where s q s the amount of the th commodty suppled c s p s p j r R F j k r j s the supply calbraton coeffcent of the th commodty s the supply prce of the th commodty s the supply prce of the j th product s amount of ranfall Temperature s the supply prce elastcty of the th product s the supply cross prce elastcty of the j th products that are competng the th product ranfall elastcty temperature elastcty s the set of relevant product that compete wth the th product. 2.2 The Demand Equatons On the other hand, the demand (consumpton) quantty of a commodty s set to depend on ts own prce, the prces of close consumpton substtutes or complementary commodtes and the consumer per capta ncome. Demand and prces are consdered as uncertan varables. So, the system of the demand functon can be expressed as follows: Where d q b c p q d b * (p c ) η * j (p c j ) η j * I,,j 1, s the amount of the th commodty demanded s the demand calbraton coeffcent of the th commodty s the demand prce of the th commodty μ (2) 5

6 I j s per capta ncome s the demand prce elastcty s the demand prce elastcty of the th commodtes that are complementary or substtutes for the th commodtes. s the ncome elastcty of the th commodty. The term represents the per capta ncome of the consumer whch s calculated n the model as the outcome of the Gross Domestc Product over the number of total populaton. Ths term could also provde the possblty of explorng future developments that may happen n the demand sde (Abdel KARIM, 2002). 2.3 Food securty ndcators Self-suffcency rato (SSR) Sorghum s the major staple food for the populaton used as the food securty component n the model; whereas, sesame s a cash exportable crop. Self-suffcency rato (SSR) s used as food avalablty ndcator. SSR q s d / q 1,2, Per Capta Consumpton (PPC) (4) PPC q d / N 1,2,3 (5) Where, N denotes the populaton number. 2.4 Trade ndcators Total Exports, Total mports Total agrcultural exports, mports and balance of trade are calculated n the model as TEx = (q s q d ) p w =1,., 9 (6) TIm = (q d q s ) p w =1,...9 (7) Where, TEx and TIm n the model are the agrcultural export and mport values. q s and q d supply and demand of the commodtes p w world market prce Export/mport coverage 6

7 Ths ndex s an alternatve to the normalzed trade balance. It tells whether or not a country s mports are fully pad for by exports n a gven year. In general, economsts expect that the trade balance wll be zero n the long run, thus mports are fnanced by exports, but t may vary consderably over shorter perods. The values for ths ndex range from 0 when there are no exports to + when there are no mports. A rato of 1 sgnals full coverage of mports wth exports (trade balance). Export/Import Coverage = X M j (8) Where, X j The blateral total s export flow, and M The blateral total mport flow. 2.5 The model scenaros Two scenaros have been developed n order to smulate the mpact of clmate change. The frst scenaro (base scenaro) smulates the past perod of supply, demand, and envronment, and used as base to compare to other smulatons. The second scenaro (clmate change scenaro) smulates the nne major commodty markets under clmate change of 20% decreasng ranfall and 10% ncrease n temperature. In each scenaro, quanttes, prces, ranfall and temperature were presented n ther stochastc form. All scenaros were run smultaneously usng 1000 random samples from each of the stochastc varable dstrbutons. The BestFt dstrbuton-fttng software program that s bundled was used to estmate smooth cumulatve dstrbuton functons (CDF) for each scenaro based on annual observatons from A tme seres data for the perod were collected from secondary sources manly Bank of Sudan annual reports, FAO database, and the World Bank clmate knowledge portal. Elastctes of prces and crop yeld have been compled from secondary sources and some regresson analyss. Projected ncrease n per capta ncome and populaton has been consdered n the model. In the frst step, the dstrbuton of the stochastc varables of supply, demand, prces, ran fall and temperature have been determned wth the help program. In 7

8 the second step of the analyss all stochastc varables are appled to the mult-market model and the determned scenaros. 3. RESULTS AND DISCUSSION 3.1 The supply effects Fgures (1), (2) and (3) show the smulaton results of clmate change scenaro on the supply of cereals of wheat, sorghum and mllet whch consttute the man food securty commodtes n Sudan. In general the change n clmate of decreasng ran fall ncreasng temperature trends would lead to substantal fall n the supply of cereals. Wheat s grown n wnter under permanent rrgaton and affected only by temperature ncrease, the smulaton results fgure (1), explan a shft n the CDF curve to the left ndcatng a fall n wheat supply, that the supply under clmate change wll reduce to 286,910 tons or less at cumulatve probablty of 0.6 n compare to 319,332 tons at the same level of probablty n the basc scenaro. Wheat yelds are low due to the unfavorable weather condtons that affect productvty, where relatvely hgh temperatures preval n Sudan durng wnter. Wheat yelds have vared consderably, sometmes below 1 MT/ha but more often well above 2 MT/ha, especally n recent years. Nevertheless, they are below the average for developng countres as a whole by 25-30%. (Konardeas, 2009). Sorghum s the man staple food n Sudan partcularly n rural areas, t s a summer crop mostly grown under ran fed sector. Therefore, t s affected by both clmate varables of ran fall and temperature. The total effect of ran fall and temperature on sorghum supply s shown n fgure (2 ), the CDF functon explan that mean supply of 3.4 mllon tons or less could be attaned at cumulatve probablty of 0.61n the base scenaro, whle the CDF sorghum mean supply under clmate scenaro falls to 1.2 mllon tons or less at the same level of cumulatve probablty. Sorghum producton s qute volatle from year to year as ts producton follows ran fall fluctuatons, the country produces surplus n good ran seasons and some years fall short (El-Dukher, 2011).The mpact on sorghum wll affect the country food securty as a whole snce t was the major component of food securty. 8

9 Mllet s produced and consumed locally, t s also affected by both ran fall and temperature snce t s totally produced under the ran fed sector. The CDF smulated mean of mllet supply under the base scenaro s 573 thousand tons attaned at cumulatve probablty of 0.62 wth hgher standard devaton. Whle, under clmate scenaro the CDF supply mean s around 446 thousand tons at the same cumulatve probablty level. Fgure (1): The CDF dstrbuton of wheat supply, under the two scenaros 9

10 Fgure (2): The CDF dstrbuton of sorghum supply, under the two scenaros Fgure (3): The CDF dstrbuton of mllet supply, under the two scenaros Sesame and groundnuts are the most mportant ol seed crops and consdered as cash commodtes. Sesame s the major exported crop n Sudan. It s entrely produced under ran fed sector. The CDF smulaton results (fgure, 4) shows that sesame supples under the clmate scenaro amounted to 225,995 tons or less at 0.61cumulatve probablty; n compare to 313,991 tons or less at the same level of probablty n the base scenaro. Temperature and the amount and dstrbuton of ran fall play an mportant role n sesame producton. Groundnut s another mportant ol exported crop. It s produced under both the rrgated and ran fed sectors. The CDF dstrbuton graph of groundnuts supply shows that the mean supply could be amounted to 839,199 tons or less at 0.6 cumulatve probablty n the base scenaro, compared to 688,762 tons at the same probablty level n the clmate change scenaro (fgure, 5). 10

11 Fgure (4): The CDF dstrbuton of sesame supply, under the two scenaros Fgure (5): The CDF dstrbuton of groundnuts supply, under the two scenaros Cotton s one of the most mportant commodtes n the export lst, although ts relatve share n foregn exchange declned recently. It s affected by temperature, snce t s grown under the permanent rrgated sector. In fgure (6), the CDF dstrbuton of cotton supply shows a slght decrease n the clmate scenaro that at probablty level of 0.6 wth mean supply was 130,092 bales or less wth regard to 144,968 bales or less at the same probablty level. The margnal possble reducton n supply s attrbuted to the low temperature elastcty. 11

12 Fgure (6): The CDF dstrbuton of cotton supply, under the two scenaros Sugar producton s operated by publc companes under permanent rrgated sector; t s also affected by possble temperature rse. Sugar consumpton has ncreased sgnfcantly n Sudan. Hstorcally, Sudan has mported the bulk of hs requrements; however, the country s self-suffcent n some years as a result of mprovement n producton effcency and ratonal consumpton. Sugar supply CDF dstrbuton under clmate scenaro show a consderable fall to 2624,904 tones or less at 0.6 cumulatve probablty n compare to 694,349 tons or less at the same probablty level n the base scenaro (fgure, 7). 12

13 Fgure (7): The CDF dstrbuton of sugar supply, under the two scenaros Arabc gum s a non-wood forest product, plays an mportant role n foregn trade of Sudan. The country s a leadng producer of Arabc gum; supplyng around two thrd of the total world tradng. Fgure (8) provdes nformaton about the smulaton of possble CDF dstrbuton of clmate scenaros, Arabc gum supples wll be affected drectly by ran fall and temperature to fall to 26,264 tons at 0.6 cumulatve probablty from 29,565 tons at the same level n the base scenaro. Fgure (8): The CDF dstrbuton of Arabc gum supply, under the two scenaros 13

14 Lvestock subsector plays basc role n the economy of Sudan. The sector accounts percent of the GDP (Bank of Sudan, 2014). It satsfes all domestc consumpton of anmal products and contrbutes sgnfcantly for foregn exchange earnngs through exports of lfe anmal. Fgure (9) gve an overvew of the lvestock CDF supply dstrbuton of the model scenaros. Under clmate scenaro the supply mean would sgnfcantly decrease to 39, 580,320 heads or less at 0.7 cumulatve probablty where as n the base scenaro the possble supply s 45,728,535 at the same probablty level. The consderable declne n the supply numbers of lvestock s manly because of that lvestock reles on natural pasture n ts feedng whch n turn depends on ran fall ntensty and varablty, coupled wth temperature effect makes lvestock hghly responsve to clmate change. Fgure (9): The CDF dstrbuton of lvestock supply, under the two scenaros 14

15 3.2 Food Securty effects Self-suffcency rato (SSR) In the model, the SSR rato reflects self suffcency from food securty cereals commodtes of wheat, sorghum and mllet. Fgure (10) shows the smulaton results of the CDF graph of the base and clmate scenaros. In the base scenaro, the rato could possbly reach 71% or less at 0.48 cumulatve probablty levels. Sudan s not a selfsuffcent of cereals, where, startng from the begnnng of the 1980s, the country became a net mporter of wheat (Fak, 1996). Sudan's wheat supply and consumpton drectons have resulted n a contnuous and varable defct between domestc needs and local producton. Whle, the country s normally self- suffcent of sorghum and mllet except n low ran seasons and drought tmes. Under the clmate scenaro the selfsuffcency could possbly go down to 59% or less at 0.48 probablty level as shown by the CDF graph n fgure (10). The possble fall n the SSR reflects the expected reducton n wheat, sorghum and mllet supples due to the ran fall decrease and temperature rse n the clmate scenaro. Under ths scenaro the country wll be oblged to cover ts defct through mportng sorghum and mllet besde wheat normal mports to secure food avalablty Per capta consumpton (PCC) Per capta consumpton reflects the annual average share of populaton from domestcally produced food securty cereals of wheat, sorghum and mllet. Fgure (11) show the smulated dstrbuton CDF for food per capta consumpton ndcator for the two scenaros. In the base scenaro; the CDF graph shows that the cumulatve probablty of attanng PPC mean of 199 kg/person/year or less s 0.48, whch s hghly above east Afrcan countres average of 72 kg/person/year (Mkumbwa, 2011). In the clmate scenaro the PCC mean wll decrease to 154 kg/person/year or less at the same level of probablty. The reducton PPC n the clmate scenaro s attrbuted to the decrease n cereals producton resulted from clmate change coupled wth ncrease n consumpton by the projected ncrease n populaton numbers. In total, self-suffcency rato and per capta consumpton are ndcators for food avalablty n the country whch are expected to face consderable shortages under clmate change. 15

16 Fgure (10): The effect on SSR of wheat, sorghum and mllet Fgure (11): The effect on PPC of wheat, sorghum and mllet 16

17 3.3 Trade effect Total exports Total exports n the basc scenaro are the export value of sorghum, sesame, ground nut, cotton, Arabc Gum and lvestock. Whle, n the clmate change scenaro the lst of exports only ncludes sesame and cotton, the other commodtes would shft to the mport lst because of the notceable supply fall n these crops. Fgure (12) outlays the smulaton results total export value n the two scenaros. The total value of exports wll decrease to US $ mllon or less at cumulatve probablty of 0.6, compared to US $ or less mllon n the base scenaro at the same level of probablty. In general, the value of total exports would decrease sgnfcantly because of the decrease n exported quanttes however; t could be partally compensated from the possble ncrease n world food prces Total Imports Wheat s major food mport substtute. There s an ncreasng trend of wheat mports and consumpton n Sudan. That was attrbuted to rapd urbanzaton and the ncrease n per capta ncome (Elgal, 2017). In the base scenaro the mport commodty lst consst of wheat and sugar. However, under the clmate change scenaro the lst of mports has extended to nclude sorghum, mllet, ground nut and lvestock. Lookng at the fgure (13), the total value of mports n the clmate scenaro would ncrease to US $ 4.3 bllon or less at cumulatve probablty of 0.6, whereas, the base scenaro mport value s around US $ 1.6 bllon at the same level of probablty. Therefore, the country s under rsk of clmate change and possble ncreases n the world food prces whch wll aggravate the defct n trade balance Export / mport coverage There s an ncreasng concern n the country over securng enough resource funds from exports to cover ts mports. Fgure (14) provdes nformaton of the smulaton results of the possble outcome of export/mport coverage rato under the two scenaros. The coverage rato s below one n the base scenaro wth a mean of 0.96 or less at 0.45 probablty level, whch ndcates the nablty of the country to cover all country mports from exports. Under the clmate change scenaro, the coverage rato wll fall to 0.09 or less at cumulatve probablty of 0.45; ths s because most of the exported commodtes have turned nto mports. The stuaton wll get worse f there s a possble 17

18 ncrease n world food prces and the country wll not be able to cover ts food mports from exports. Clmate change wll negatvely affects the agrculture external sector by the drect fall n commodty supples where the country wll turn to be a food net mport country. And wll affect the sector ndrectly that f world food supply falls, prces wll ncrease and consequently ncrease mports bll. Although there s a possble ncrease n world prces, but mght not offset the export losses because of the shft of most of export commodtes to the mport lst. 18

19 Fgure (12): The CDF dstrbuton of total exports, under the two scenaros Fgure (13): The CDF dstrbuton of total mports, under the two scenaros Fgure (14): The CDF dstrbuton of export/mport coverage rato, under the two scenaros 19

20 4. CONCLUSION AND POLICY RECOMMONDATION The am of ths paper s to assess the mpact of clmate change on food securty and trade n Sudan. The paper has appled a stochastc mult-market model to quantfy the possble effects of clmate change. The model starts by formulatng supply and demand functons where prces, ranfall and temperature are assumed to play a major role n the model; n the supply and demand functons, quanttes, prces ranfall and temperature are consdered as stochastc varables and represented n the model by ther dstrbutonal functonal form. The model has been extended to nclude food securty and trade ndcators. The overall mpact of scenaros smulatons of the projected clmate varables of ran fall and temperature n the model has reflected n a consderable reducton n the supples of all commodtes covered by the model whch have negatvely affected food securty stuaton shown by the low ratos of self-suffcency and per capta consumpton. As well as the poor performance of the external sector where total exports have recorded a remarkable decrease n one hand, on the other hand, mports have ncreased dramatcally. Fnally, the country wll not be able to cover ts mports of food through ts agrcultural exports. Interventons to mtgate and adapt to potental adverse mpacts of clmate change by the horzontal expanson n the permanent rrgated sector s needed, where the adverse mpact of clmate change s lower than the ran fed sector. Such nterventons would have mportant mplcatons for future food securty, trade and overall growth of the economy. 20

21 References Abdel Karm E. E., (2002), The Impact of Uruguay Round Agreement on Agrculture on Sudan s Agrcultural Trade. PhD Thess, HU Berln, Shaker Verlag. Bank of Sudan, (2014) Annual Report, Khartoum, Sudan El-Dukher, I., Crno, O. O., Ahmed S. E. and Slvestero K. M., (2011), Revew of the Food Securty and Natural Resource Stuaton n Sudan, DCG Report No. 63. Elgal, M. B., Mustafa, R. H., and Krschke, D., (2017). Wheat and Sorghum Food Polcy n Sudan (n press) Fak, H. M., (1996), Producton Stuaton and Economc Aspects, Wheat Producton and Improvements n the Sudan, Chapter 1, Edtors: Ageeb, O.A., Elahmad, A. B. and Saxena, M.C., page ICARDA. Ibrahm A. M., ( 2015), Assessment of Adaptaton Optons for Copng wth Clmate Change Impacts on the Lvelhoods of Pastoral Communtes n Butana Regon, PhD Thess, Sudan Academy of Scences, ARC, Sudan. Jechltschka, K. und Lotze, H. (1997). Theore und Anwendung enes Mehr-Markt- Modelles zur Sektoralen Analyse von Agrarpoltken. Zetschrft für Agrarnformatk Krschke, D., Jechltschka, K. (2002), Angewandte Mkroökonome und Wrtschaftspoltk mt Excel. Lehr und Anletungsbuch für computergestützte Analysen. München, Verlag Vahlen. Konanderas, P., (2009), Assessng Sudan s Export Dversfcaton Potental n Agrcultural Products, Maxwell Stamp PLC. Mkumbwa, S. S., (2011), Cereal food commodtes n Eastern Afrca: consumpton - producton gap trends and projectons for 2020, Munch Personal RePEc Archve, MPRA Paper No Sayed A. M., and and Abdala. B., (2010), IFAD., SUDAN Envronmental and Clmate Change Assessment, Prepared for IFAD s Country Strategc Opportuntes Programme , ECCA No SD. USAID, Unted Natons Envronment Program and the World Trade Organzaton Trade and Clmate Change, report, 2009 Prnted by WTO Secretarat, Swtzerland 21