The ecological and socio-economic role of Prosopis juliflora in Eritrea [Elektronische Ressource] : an analytical assessment within the context of rural development in the Horn of Africa / Harnet Bokrezion

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Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2008
• Nombre de lectures: 189
• Langue: English
• Poids de l'ouvrage: 8 Mo

Extrait

TheEc ologicalandSocio­economicRoleof
Pr osopisjuliflorainEr itrea
AnAnalyticalAssessmentwithintheContextofRural
DevelopmentintheHornofAfrica
Dissertation
zurErlangungdesGrades
„D oktorderNaturwissenschaften“
imPromotionsfachGeography
amFachbereichChemie,PharmazieundGeowissenschaften
derJohannesGutenberg­UniversitätMainz
HarnetBokrezion
geb.inHeidelberg
Mainz, 2008Dekan:Prof.(namedeletedduetodataprotection)
1.Berichterstatter:Univ.-Prof.(namedeletedduetodataprotection)
2.Berichterstatter:Univ.-Prof.(namedeletedduetodataprotection)
TagdermündlichenPrüfung:24.Oktober,2008!"#$#"%&'()
!"#$*+%&'()EidesstattlicheErklärung
Hiermitversichereich,HarnetBokrezion,anEidesStatt,daßichdieArbeitselbständig
undohnefremdeHilfeverfaßtundkeineanderenalsdieangegebenenHilfsmittel
benutzthabe.DieseErklärungschließtauchalleZeichnungen,bildlichen
Darstellungenunddergleichenmitein.DiejenigenStellenderArbeit,diedemWortlaut
oderdemSinnnachanderenWerkenentnommensind,sindinjedemFallunter
AngabederQuellederEntlehnungkenntlichgemacht.Gleichzeitigversichereich,daß
dieArbeitnochnichtveröffentlichtoderineinemanderenPrüfungsverfahrenals
Prüfungsleistungvorgelegtwordenist.
HarnetBokrezion
Mainz, Juli2008Contents
I. Foreword.................................................................................................................................................1
II. Acknowledgement..................................................................................................................................3
III. Introduction:ProsopisjuliflorainEritreawithintheGlobalContextofRuralDevelopmentand
EnvironmentalSustainability................................................................................................................5
IV. Methodology...........................................................................................................................................7
V. ProblemStatement...............................................................................................................................10
Chapter1: GeneralAspectsonProsopisjuliflora
1.1 OriginandWorldwideDistribution...................................................................................................14
1.2 ProsopisjuliflorainBotanicalTerms.................................................................................................17
1.3 WeedorWondertree?-AShortInsightintotheStateofInternationalResearchonProsopis....19
Chapter2: PhysicalandAnthropologicGeographicalSummaryandRegional ProsopisHabitats in
Eritrea
2.1 LandAreaandClimateinEritrea......................................................................................................24
2.2 Agro-climaticZones..............................................................................................................................26
TheCoastalPlains(EasternLowlands)..................................................................................................26
TheEasternEscarpmentsandthe“GreenBelt”Zone............................................................................27
TheHighlands.........................................................................................................................................28
WesternEscarpments..............................................................................................................................29
TheWesternLowlands............................................................................................................................30
2.3 Geology,WaterResourcesandSoils....................................................................................................31
Geology..................................................................................................................................................31
Surfacewateranddrainagesystems.......................................................................................................32
Groundwaterresources...........................................................................................................................34
2.4 Population.............................................................................................................................................38
2.5 LandUseandRuralLivelihoodSystems...........................................................................................39
2.6 NaturalResources,VegetationandEcosystems................................................................................41
Chapter3: ProsopisjuliflorainEritrea
3.1 BriefAssessmentofInvasiveandEndangeredTreeSpeciesinEritrea...........................................43
3.2 Introduction,GeographicDistributionandLocalNomenclatureofP.juliflora..............................46
3.3 EcologicalAspectsofProsopisjuliflorainEritrea.............................................................................54
3.3.1 AnOverviewofP.juliflorawithinEritrea’sEcosystems........................................................54
RiverineForests/riverbeds........................................................................................................57
Irrigatedcropland.......................................................................................................................62Roadsides...................................................................................................................................63
Settlementareas...........................................................................................................................65
3.3.2 AssessmentofP.juliflora’sInvasivenessanditsImpactonNativePlantSpecies.................66
3.3.3 SoilProcessesunderP.juliflorawithinLandManagementEfforts........................................77
3.3.4 P.juliflorawithinRegenerationEffortsofSalineandSodicSoils..........................................79
3.3.5 Prosopis-AnEcologicalIndicatorforDesertification?..........................................................81
3.4 TheSocio-economicImpactofP.juliflorainEritrea.........................................................................87
3.4.1P.juliflorainfestationinCropLandAreasandSilvo-PastoralRangeLands.........................87
3.4.2P.juliflora’sRolewithinAgroforestry-Systems........................................................................90
3.4.4P.juliflora,AnimalHusbandryandtheLivestockSector........................................................92
3.5 DoesP.julifloraEndangerNationalandHouseholdFoodSecurity?...............................................98
Chapter4: AnAssessmentoftheGeneralViewonP.julifloraamongRuralCommunities
4.1 SurveyObjectivesandMethodology................................................................................................102
4.2 TheStudyAreaandBackgroundofRespondents...........................................................................104
4.3 PerceptionsaboutOccurrenceandLevelofSpread.......................................................................106
4.4 PerceptionsRegardingtheImpactofP.julifloraonCropLand....................................................112
4.5 TheImpactofP.julifloraonRangeLands,RiverineForestsandNativePlantSpecies...............117
4.6 PerceptionsregardingtheImpactofP.julifloraonLivestock........................................................127
4.7 TheSocio-economicBenefitsofProsopisinRuralCommunities...................................................135
4.8 ExperiencesRegardingtheInvasionofProsopisinsideSettlementAreas....................................141
4.9 GeneralAttitudes,PerceptionsandExperiencesregardingP.juliflora.........................................142
4.10 ViewsonManagementandActionPlanEfforts..............................................................................146
4.11 PerceptionsofProsopisintheSemi-aridWesternLowlandsvsthoseinAridEasternLowlands151
Chapter5: TheQuestionofManagementofP.juliflorainEritrea
5.1 TheCaseofMisidentificationofProsopis...........................................................................................155
5.2 ManagementStrategiesinthePastandToday.................................................................................156
5.3 Promotion,ControlorEradication-anAssessment........................................................................160
5.4 ADraftFrameworkofAppropriateMeasureswithinaNationalActionPlanonProsopis
forEritrea............................................................................................................................................169
5.5 ShortAssessmentofsomeNon-mechanicalControlMeasuresintheContextofEritrea...........180
Biocontrol............................................................................................................................................180
Ecologicalcontrol(or“auto-control”)..................................................................................................181
Chemicalcontrol..................................................................................................................................182
5.6 MaximisingthePotentialofP.juliflorawithinRuralandUrbanEconomies................................182
Energyresourcesandtimberproduction..............................................................................................183
Fodder.......................................................................................................................