Thesis (MSc)--Stellenbosch University, 2000. / Full text to be digitised and attached to bibliographic record. / ENGLISH ABSTRACT: Miombo woodland occupies the greater portion of the Zambezian phytoregion where communities derive products and services for their livelihood. The managers of these resources have for many years neglected these crucial needs, which has important implications for silvicultural systems and management interventions. The overall objective of this study was to document the miombo species utilisation preferences by local communities in Tabora, Tanzania. This information was obtained using individual interviews and village meetings. A simple line transect inventory survey was carried out to assess the miombo resources adjacent to the studied villages. The villagers in Tabora have knowledge of the importance of their woodland resources and put different species to different uses, with some overlap where a species has multiple uses. The surveyed villages differ in the utilisation of miombo resources, where the choice and quantities used depend on their proximity to urban areas. There is strong preference for suitable species for building poles and due to scarcity some people now use mud bricks for house construction. Suitable timber tree species are scarce in the Urumwa Forest Reserve and now low quality species such as Sterculia quinqueloba are used. For firewood live trees are cut and dried, however any combustible material is used. Not surprisingly the community's use priorities differ from the management priorities of the Forest Department. The use of miombo products for income generation in the studied villages is influenced by the proximity to urban areas and villagers do not perceive commercialisation of these products as depriving them of resources. The use of woodlands for cultural and religious purposes in Tabora, though important to the spiritual wellbeing of people, has declined over the years. The fact that the villagers choose particular miombo trees for different purposes is an indication of some kind of local knowledge and management. The Urumwa Forest Reserve is now an open access resource as villagers have depleted wood resources adjacent to their settlements. Awareness of the causes of miombo resource depletion in these villages is positively correlated with the proximity to urban areas and wood scarcity. Community participation in management of natural resources is still new in Tabora as few villagers were aware of the new government management interventions of the Urumwa woodlands, and awareness seems to be limited largely to males and leaders. There is active management of indigenous trees protected on farms for various uses and exotic tree-planting mainly for fruits and shade, is done around homesteads, but with no de jure rights of ownership. Tree planting in this area is severely hindered by drought, insects and termite attack to seedlings and this has made people depend entirely on the miombo for their wood requirements. The simple wood resource inventory survey carried out in this study has showed that the Urumwa miombo woodland is heavily utilised. This has resulted in poor tree diameter distribution and species composition. The smaller tree diameters recorded in the Urumwa Reserve indicate that the potential of this woodland for timber production is low compared to other products. The priority products documented in this study form base-line information for management plans and silvicultural systems suitable for sustainable management and utilisation of these woodlands in future. / AFRIKAANSE OPSOMMING: Miombo bosveld beslaan die grootste gedeelte van die Zambezi vegetasiestreek waarin 'n groot menslike bevolking produkte en dienste uit hierdie bioom genereer om 'n bestaan te maak. Bestuurders van hierdie bronne verwaarloos al jare hierdie kritiese behoeftes, en dit het belangrike implikasies vir boskundige sisteme en bestuurstussentredes. Die hoofdoel van hierdie studie was om die miombo spesiesbenutting-voorkeure van plaaslike gemeenskappe in Tabora, Tanzanië te bepaal. Inligting is bekom deur individuele onderhoude en dorpsvergaderings. 'n Eenvoudige lyn-transek opname is uitgevoer om die miombo-bronne langs die bestudeerde dorpies te bepaal. Die dorpsbewoners in Tabora dra kennis van die belangrikheid van hul bosveld bronne en gebruik verskillende spesies vir verskillende doele, met oorvleuling waar spesies meervoudige gebruike het. Die dorpies wat ondersoek is verskil in die benutting van miombo bronne waar die keuses en kwantiteite wat gebruik word bepaal word deur die nabyheid aan stedelike gebiede. Daar is 'n sterk voorkeur vir spesies geskik vir boupale en as gevolg van skaarste van die spesies gebruik sommige inwoners nou klei bakstene vir huiskonstruksie. Geskikte spesies vir die produksie van hout is skaars in die Urumwa Forest Reserve en lae kwaliteit spesies soos Sterculia quinqueloba word gebruik. Lewende bome word gekap en gedroog vir brandhout alhoewel enige brandbare materiaalook gebruik word. Dit is nie verbasend dat die gemeenskap se gebruiksprioriteite verskil van die bestuurs-prioritiete van die Departement Bosbou nie. Die gebruik van miombo-produkte vir inkomste-generasie in die bestudeerde dorpies word beinvloed deur die nabyheid aan stedelike gebiede en dorpsbewoners beskou nie dat die kommersialisering van sulke produkte hul van hulpbronne ontneem nie. Die gebruik van bosveld vir kulturele en godsdienstige doeleindes in Tabora, wat belangrik is vir die geestelike gesondheid van die inwoners, het oor die jare afgeneem. Die feit dat dorpsbewoners besondere miombo-bome kies vir verskillende gebruike is 'n aanduiding van 'n mate van plaaslike kennis en bestuur. Die Urumwa Bosreserwe is nou 'n vrye toegang hulpbron omdat dorpsbewoners houtbronne na aan hul dorpies uitgeput het. Bewustheid van die oorsake van die uitputting van miombo hulpbronne naby die dorpies is positief gekorreleerd met die nabyheid aan dorpsgebiede en houtskaarste. Gemeenskapsdeelname by die bestuur van natuurlike hulpbronne is 'n nuwe konsep in Tabora omdat min dorpsbewoners bewus is van nuwe bestuursintredes deur die regering by die Urumwa bosveld en bewustheid blyk beperk te wees tot mans en leiers. Daar is aktiewe bestuur van inheemse bome wat vir spesefieke gebruike beskerm word op plase en uitheemse boomaanplantings, hoofsaaklik vir vrugte en skadu, word by huise gemaak. Daar is geen de jure regte in die geval nie. Boomaanplantings in die gebied word ernstig beperk deur droogte, insekte en termietaanvalle op saailinge en dit veroorsaak dat mense uitsluitlik op miombo staat maak vir hul houtbehoeftes. Die eenvoudige houthulpbron-opname wat in die studie onderneem is het bewys dat die Urumwa miombo bosveld strafbenut word en dat daar geen balans tussen aanwas en hout benutting is nie. Dit veroorsaak swak boomdeursnit-verspreiding en spesies samestelling. Die kleiner boomdeursnitte wat in die Urumwa Bosreserwe aangeteken is dui daarop dat die potensiaal van hierdie bosveld vir houtproduksie laag is en slegs beperk is tot ander produkte. Die voorkeur-produkte wat in hierdie studie gedokumenteer is vorm kerninligting vir bestuursplanne en boskundige sisteme wat geskik sal wees vir die toekomstige volhoubare bestuur en benutting van hierdie bosvelde.

Changes in land use and land cover are a global issue of concern, especially with regard to possible impacts on biophysical processes which affect the hydrological functioning of a system. Tanzania is no exception to this concern. This study, therefore, addresses the implications of land use alterations on the hydrodynamics of the Kilombero River Basin, specifically with regard to the Kilombero Valley’s wetlands and water resources, which have been altered and exploited to a great extent. As its starting point, the study embarked on mapping the current land cover in the Kilombero Basin and the quantification of the historical changes. The study revealed significant changes and, in recent years, increased rates of clearing natural vegetation cover and conversion to agricultural land. The most affected area of the Basin was the Kilombero Valley, a Ramsar Site and formerly extensively inhabited by wildlife, but which now has 62% of its area converted into agricultural and/or human settlements. In line with this observation, the study used two approaches for the impact analysis, a regional scale and a local scale approach. Plant physiology, soil moisture and micro-meteorological measurements were undertaken to quantify the impact of land cover change at local scale. Sensing techniques were then applied to assess the spatial extent of the changes and the basin scale (regional) impact thereof. Investigation of hydrological processes at a local scale placed emphasis on the implications of forest conversion from indigenous Miombo woodland to exotic Teak (Tectona grandis) forests. Field measurements showed the distinctive nature of Teak trees consumptive water use, both in quantity as well as in regard to the seasonal variation as compared to the native Miombo woodland forests. Teak was found to have higher transpiration rates, both during the rainy season (where the rates were approximately 10-fold higher than that of Miombo) and the period immediately after the cessation of rainfall, with consumptive water use rates being four-fold higher than that of Miombo. This contrast in water use was further observed in the measured soil water fluxes which evidenced a large difference in the components of the soil water balance. Less recharge was observed in the Teak forests suggesting significant impacts on the replenishment of groundwater resources in the study area. Assessment of the basin scale impacts of the land cover changes on the evapotranspiration (ET) regime was undertaken using the Surface Energy Balance System (SEBS) remote sensing model. Validation was provided by the Teak field sites and through the monitoring of ET from sugar cane using a Large Aperture Scintillometer (LAS). Results suggest a decrease in ET during the dry season. There is a clear transition of ET that follows the land cover transition from the natural and more adaptable vegetation, to rain-fed dependent crops and bare lands, where minimal ET is observed during the dry season. Similar seasonal leafing, and therefore a similar ET pattern, is observed with the conversion of natural forests to deciduous plantation forests. Irrigated crops, on the other hand, were found to have persistently higher ET throughout the year regardless of rainfall variability. This implies that land cover change in the Kilombera Valley is resulting in higher water use and less recharge in the wet season and a correspondingly lower ET (and possibly lower river flow) in the dry season than would occur under natural conditions. This research provides valuable information relevant to all stakeholders in the Kilombero River Basin (i.e. both smallholders and commercial sugarcane farmers, the forestry industry, Basin Water Authorities etc.). This information will help to inform decision-making around the sustainable management of the water resources in the Kilombero Valley for food security as well as for sustaining livelihoods and ecosystems. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.