Theses and Dissertations Collection

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Gender and household food security situation in Chagga homegardens: a case study of Rombo district
(Sokoine University of Agriculture, 2003) Edward, Mamkwe Claudia
The study was conducted in Rombo District in Kilimanjaro Region, Tanzania. The objective of the study was to assess gender and household food security situation in Chagga homegardens. A multistage sampling was employed to obtain a sample of 100 respondents. Primary data were obtained through personal observation, administering of structured questionnaire and focus group discussion. Secondary data was obtained from District Agriculture and Livestock Development Office and from Sokoinc University of Agriculture Library, Morogoro. Data were analysed by using Statistical Package for Social Sciences (SPSS) computer program. The results of the study showed that homegarden crops contribute 67.7%, livestock 29.0% and homegarden trees 3.6% of the income from homegardens. In total the homegardens contributed 53.1% of the average household income while other sources were off-farm activities 35.9% and from open field farm was 11.0%. The homegardens contained about 27 species of food crops of which 12 species arc reported by more than 70% respondents that are in danger of disappearing More than 65% of the households in the study area were food insecure. Female-headed households were more vulnerable to food insecurity than male-headed ones. Socio-economic factors such as income, size of open field farm, level of education, sex and age of the head of household influence household food security significantly at (P< 0.05). The study also found that gender division of labour subjects women to high workload, which might influence household food security. Decisions on various production and expenditure of household resources were mostly done by men and this influences household food security. The study conclude that Household food security is significantly (P<0.05) influenced with socio-economic factors such as average income, main occupation, sex, age and level of education of the household head, and socio-cultural factors. It is recommended that the government through its policy makers and the development planners should recognise and promote the role of women as producers and providers of food to the household. Analysis of food security situation and type of production system need to be carried out in various regions in order to suggest mechanisms for improving food security over time. Government assistance is needed to sensitise people to shift to areas with plenty of land for crop cultivation.
Land use/cover change and socio economic factors influencing land cover dynamics in the Selous-niassa wildlife corridor, Nachingwea district, Tanzania
(Sokoine University of Agriculture, 2007) Ntongani, Wilbard Augustine
Selous-Niassa miombo woodland ecosystem of southern Tanzania and northern Mozambique represent one of the largest, most significant, trans-boundary natural ecosystems in Africa. This study examined socio-economic factors influencing land cover dynamics, and conservation threats to the Selous-Niassa wildlife corridor across Nachingwea district, Tanzania. Land cover dynamics was assessed using Landsat images of 1978, 1993 and 2000. House hold survey, field observations and focus group discussions were used to obtain socio-economic data on factors influencing land cover dynamics and logistic regression model was used to analyze the data. The results revealed that there has been significant land cover transformation from one class to another. In the period of 15 years (1978-1993) cultivated land increased by 658.7%, settlements increased by 22.9%, grassland decreased by 93.5%, closed woodlands decreased by 15%, open woodlands decreased by 5.9%, forest lands decreased by 8.7% and scrublands decreased by 1.4%. In the period of 12 years (1993-2005) bushed grassland increased by 64.2%, closed woodlands decreased by 18.6%, cultivated land increased by 65.6%, forest land by 10.7%, open woodland decreased by 8.8% and scrublands decreased by 1.4%. Landcover change per year has been found 0.54% relatively low compared to national land cover change of 45% per year in the study area. Land tenure, shifting cultivation and crops prices were among major factors influencing land cover dynamics. Wildfires, agriculture encroachment, and timber harvesting were found to pose high conservation threats to the corridor. It is were used to obtain socio-economic data on factors influencing land cover dynamics and recommended that the government implement policies, laws and regulations relating to natural resources and land planning in order to improve land tenure in villages bordering the corridor. Establishment of a buffer zone around the corridor is of significant importance in order to reduce possible future encroachment into the corridor.
The role of local institutions in regulating resource use and conflict management: the case of Usangu plains, Mbalali district, Tanzania
(Sokoine University of Agriculture, 2002) Mbwilo, Agrey Job Thomas
Recent development in sustainable natural resource management advocates decentralization of power and responsibilities to local level institutions. Sustainable resource management in Tanzania is basically dependent on the peasants at the local level. Given this reality therefore, the role of local institutions and their effectiveness in resource use and conflict management are decisive in bringing about sustainable natural resources management. This study examined the role of local institutions in regulating resource use and conflict management in Usangu. Specifically the study investigated land use practices in the study villages; land use conflicts and their underlying courses; and the role of local institutions in regulating resource use and conflict management. The study was conducted in two phases. Phase one involved Participatory Rural Appraisal. The second phase involved a structured questionnaire survey as a major tool for data collection. Participatory observation and secondary sources were used to gather supplementary information. Data collected through PRA in phase one were analyzed with the help of the participants. The Statistical Package for Social Sciences was used to analyze quantitative data generated by questionnaires. The study revealed the existence of land use conflicts in the area. These conflicts centered on competition for resources such as water and land between crop cultivation and livestock. The study also revealed the presence of two traditional local institutions namely: council of village elders and traditional guards and four externally sponsored local institutions namely; village council, irrigation committee, livestock association and the police. With respect to conflict resolution, the study showed that both formal and informal mechanisms played an important role in conflict resolutions. Although village governments ranked high among the institutions encountered in the study villages with regard to conflict resolution, observations showed that village governments were not answerable to the people who elected them into offices. Most of the decisions at the village level were made outside the recognized “loci” for decision-making and some of these decisions were made contrary to the wishes of the villagers. The study concludes that, changes in land use are a function of both biophysical as well as changes in the socio-economic factors and that most of the existing local institutions are not well organized in terms of operation and management of local resources as evidenced by the prevalence of land use conflicts and unsustainable use of resources in the area. Furthermore lack of popular participation in resource use decision-making has hindered the establishment of democratic and efficient institutional arrangement at the local level to control imprudent resource use. The presence of traditional institutions such as the traditional guards and the council of village elders show that there exists institutional potential at the local-level from which new institutions could be built upon to carry out desired resource management functions. The study recommends that communities should be mobilized and be empowered to manage natural resources through education programs that emphasize the significance of human relationships with natural resources and the society based legal rights over resources. The study also recommends that new roles and functions of existing local institutions be developed and that there is great need to evaluate the performance of state rice farms and Usangu game reserve projects whether or not they are economically and socially viable. If not, the government should consider giving these areas to the local people, as a way of easening the conflicts between different land use.
The role of Bahi swamp wetland in enhancing household food security and income of adjacent communities
(Sokoine University of Agriculture, 2010) Rweyemamu, Renatus
The study was conducted to assess the role of Bahi swamp resources in enhancing household food security and income of adjacent communities. Specifically, the study assessed the socioeconomic activities in the swamp with a potential contribution to local livelihoods, the contribution of the swamp in enhancing household food security and income and the level of local dependence on the sw'amp. Two villages (Makulu and Nagulo-Bahi) were involved. Data were collected through questionnaire, PRA techniques (resource mapping, key informant interviews and focused group discussions) and direct observation. Data were summarized and analysed using Microsoft Excel. SPSS and content analysis. Other data from discussions were analysed through relative ranking. The socioeconomic activities with potential contribution to food security and income of adjacent communities in order of importance included crop cultivation, fishing, livestock grazing and collection of thatching grasses. Cultivation of paddy rice contributed significantly to household food security generating 65.4% of total household food crop production compared to other crops grown in drier areas adjacent to the swamp. Fishing played a substantial contribution to household food security through household consumption of 10% of fish caught. For household income, sales of paddy rice from the swamp contributed 59.6% while fish sales contributed 36% of the total annual household income. Multiplier activities emerging during fishing season facilitate income to a wider group of communities. On average, 56.2% of the population depend on the swamp for daily socio-economic activities associated with generation of household food and income. The Bahi swamp and related products play a significant role iniii enhancing local livelihoods for the adjacent communities. Planning for wise use of the swamp in respect of the dominant socioeconomic activities will likely improve its contribution to livelihoods.
Assessment of the extent of elephant damage on baobab trees (adansonia digitata) in Mkata flood plain of Mikumi National Park, Tanzania
(Sokoine University of Agriculture, 2006) Nicolaus, William
A study was conducted in Mkata flood plain of Mikumi National Park (Tanzania) during the dry season of 2003. The aim of the study was to assess the extent of elephant damage to baobab trees and other woody vegetation, with special consideration that elephants will use baobabs extensively when water is limited. Ground survey was employed to assess 50 baobab trees and 724 other woody species in 20 belt transects. Baobab trees were assessed five times at 3-week intervals to monitor new elephant damage. The Mkata river survey was undertaken to see whether there was any area with water. Qualitative survey of baobabs showed 96% of all trees had old damage, 40% of all trees had recent damage and 20% of all trees had new damage. Quantitative survey of baobabs revealed that, recent damage was significantly higher than new one. There was no significant difference in damages between young, medium sized and large baobabs. Medium sized baobabs were damaged more significantly than large baobabs. Damage to baobabs did not differ significantly between different transects. The study revealed 44.6% of woody vegetation of other species to have elephant damage, 55.4% damaged by unknown agents and 0.6% were not damaged. The extent of damage to other woody vegetation was low. Regardless of the cause of damage, 53.6% of the woody species were lightly browsed, 33.3% were intermediately damaged and 13.1% were seriously damaged. Mikumi elephants selectively damaged younger woody species more than larger ones. In overall, Lonchocarpus capassa and Acacia spp. had significantly higher elephant damage than other species. However, Acacia spp. and Commiphora africana had relatively high percentage of new damages (11% and 10.7% respectively), and high preference ratio. It was concluded that, Mikumi elephants were not a threat to baobabs and other woody vegetation. A long-term study to compare elephant damage to baobabs in different dry years is recommended.
Nutrient and water dynamics in rotational woodlots: A case study in western Tanzania
(Wageningen University, 2004) Nyadzi, Gerson Isaac
Rotations of trees and crops on farms are considered as a potential technology to overcome the shortage of wood, reverse deforestation of natural forests and improve soil fertility for food security enhancement in western Tanzania, sub-Saharan Africa. However, overexploitation of soil water resources and depletion of soil nutrients have been suggested as possible negative effects of growing trees on farms in the semi-arid tropics. Such possible pitfalls undermine and even threaten a successful implementation of the woodlot technology at larger scale. Evidently, without proper understanding of the interactions and possible competition between trees and crops, the potential benefits of this agroforestry technology will not be realized. Therefore, this study was focused on improving the understanding of trcc-soil-crop interactions by examining water and nutrient dynamics of various trees planted in rotational woodlots with a 5-year cycle. Field trials were established with five-year rotational woodlots. Five tree species were compared with natural fallow and continuous maize. Inter-cropping of maize between trees was possible for the first two years of tree establishment without sacrificing maize yield. There was no evidence that trees were over-exploiting the water reserves after three years. Transpiration was greatest in A. crassicarpa and was related to stem diameter, size of the tree canopy and soil water availability. Trees depleted relatively more waler than continuous maize and natural fallow, but were able to store more water after rains. Acacia trees had high litter fall but the leaves were low in P and N, which led to N and P immobilization during decomposition. Trees retrieved leached inorganic N and made better use of it than natural fallow and continuous maize. Wood production at the end of the five-year growing period ranged from 30 to 90 Mg ha-1 while C sequestered in the aboveground biomass during the same period ranged between 13 to 30 Mg ha-1. The rate of biomass production was highest for Acacia species while the foliage nutrient accumulation was highest for Leucaena species. The wood component varied greatly among species, ranging from 32 to 85% of the total tree biomass. Maize yields were higher after growing trees than after natural fallow and continuous maize when no fertilizers were applied. The benefits of tree fallows compared to natural fallows were modest, in terms of maize yield increases. The increase in crop yields after woodlots was attributed in part to higher soil inorganic N. Maize responded to fertiliser N and P. The agronomic efficiency was about 30 kg grain per kg N applied at a rate of 50 kg fertilizer N, and 15 kg kg-1 between 50 and 100 kg N applied. Application of more than 20 kg ha"1 of P or K did not significantly increase maize yields. The benefit of woodlots expressed in terms of maize yield was more pronounced at mid and lower slope positions than at upper slopes. The significance of rotational woodlots in improving soil fertility is limited by substantial accumulation of nutrients in wood. Nutrient mining by wood exportation istherefore a major threat for the sustainability of woodlots, when the exported nutrients are not supplemented via external sources. Medium-term rotational woodlots have the potential to meet the domestic and industrial wood needs and at the same time to reduce deforestation in Sub-Saharan Africa.
A method for optimal design of timber hauling systems under conditions of uncertainty and risk
(University of New Brunswick, 1996) Fue, Goodluck E.
This thesis describes a method for designing optimal timber hauling systems under conditions of uncertainty and risk. This method distinguishes between, and incorporates, natural uncertainty and parameter uncertainty. Natural uncertainty encompasses the variation of the trucking activity times (loading and unloading times, loaded and empty travelling times), and is handled by using probability distributions. Parameter uncertainty is the inability to accurately estimate the parameters of these probability distributions. In this study, parameter uncertainty is addressed from a Bayesian perspective by incorporating, together with some sample data, subjective estimates from experts. In addition, the decision on the optimum combination of trucks, loaders and unloaders is based on the decision maker's attitude toward risk. Design scenarios are analysed by formulating the sequence of hauling activities (i.e., loading, travelling loaded, unloading and travelling empty) as a queueing system, and the equipment combinations are then evaluated by simulation. The inputs to the simulation model include actions (representing the number of trucks, loaders and unloaders), probability distributions (of loading time, unloading time, travel loaded speed and travel empty speed), estimated parameters of these probability distributions, and constants (such as amount of wood to be hauled, hauling distances, etc). Using a cost equation, the simulation outputs are converted into cost and payoff tables. Employing utility functions, which quantify the decision maker's attitude to risk, the optimum combination of trucks, loaders and unloaders is determined based on expected payoff and expected utility criteria. Using basic data supplied by Forest Engineering Research Institute of Canada (FERIC), a two-parameter gamma distribution is selected to represent the input variables in the simulation program. Calculations to estimate the parameters of the gamma distribution using Bayesian methodologies are contrasted with the classical statistical methods. Other possible applications to illustrate the applicability of Bayesian decision analysis in forestry are also presented. The thesis concludes that Bayesian statistics and decision analysis which combines expert prior knowledge with available sample data provides a better methodology for designing timber hauling systems than that provided by classical decision analysis methodologies, especially where woodlands decisions are made with limited sample data.
Growth and yield studies of pinus patula at Mount Meru plantations
(Sokoine University of Agriculture, 1998) Tharcisse, Twagirayezu
The main objective of the study was to produce a precise method for estimating growth and yield for Pinus patula at Mount Meru plantations. Using data from 75 temporary sample plots (with size varying from 0.04 to 0.71 ha) distributed over the whole plantation, different functions necessary for the building-up of the model were developed. Statistical packages (QUATRO and EXCEL) were used to fit equations for site index curves, single tree volume, height /diameter, taper, Weibul diameter distribution, increment, stand basal area,These submodels were diameter stand volume and mortality. integrated into computer model in BASIC language capable of estimating yields at a particular age under different stocking levels and thinning regimes. The stand inputs necessary to run the program are present and projection age, number of stems per ha, stand mean and standard deviation of dbh, dominant height, area per hectare and minimum top diameter. site, basal The model gives out yearly figures per ha for number of stems, mean total and merchantable volume, dbh, products. mean height, mean tree total basal area, volume and thinning The cumulative volumes, basal areas and their increments are also produced. Based on cumulative volume production, mean tree size, the mean annual volume increment and the current problem of funds for thinning operations, the no thinning option with a wider spacing of 3.0 x 3.0 m was recommended instead of the current option with three thinnings and an initial spacing of 2.5 x 2.5 m. Yield table printouts were produced based on this option and over all site classes found at Meru plantations. A stand volume table was also constructed for quick stand volume estimation.
Forest road planting and control by mathematical programming and time study analysis
(Sokoine University of Agriculture, 1985) Abeli, W S
Planning and construction of forest roads have until very recently been geared towards establishment and tending of plantation forests. Now that most of the plantations are nearing maturity, it is essential to plan and construct proper roads for harvesting purposes. Hi is study was designed to develop a comprehensive methodology that can be used by forest managers in the planning and control of forest roads. Specifically, the objectives of the study were: - To evaluate the application of mathematical programming methods to the design of safe and minimum-cost forest roads - To test the feasibility of improving and controlling forest road construction by mathematical programming - To develop a comprehensive methodology for measuring and estimating production rates and costs associated with forest road construction. To be able to plan, execute and control work operations for this study, a representative 1.3 km access road was planned and constructed at the Training Forest of the Sokoine University of Agriculture between February 1981 and May 1984. A number of mathematical models and time study methods were tested and incorporated in this study in order to develop a comprehensive methodology aimed at improving plan ning, control and cost estimation procedures. Based on the results of this study, the following observatxons and conclusions are made;Planning and construction of forest roads have until very recently been geared towards establishment and tending of plantation forests. Now that most of the plantations are nearing maturity, it is essential to plan and construct proper roads for harvesting purposes. Hi is study was designed to develop a comprehensive methodology that can be used by forest managers in the planning and control of forest roads. Specifically, the objectives of the study were: - To evaluate the application of mathematical programming methods to the design of safe and minimum-cost forest roads - To test the feasibility of improving and controlling forest road construction by mathematical programming - To develop a comprehensive methodology for measuring and estimating production rates and costs associated with forest road construction. To be able to plan, execute and control work operations for this study, a representative 1.3 km access road was planned and constructed at the Training Forest of the Sokoine University of Agriculture between February 1981 and May 1984. A number of mathematical models and time study methods were tested and incorporated in this study in order to develop a comprehensive methodology aimed at improving plan ning, control and cost estimation procedures. Based on the results of this study, the following observatxons and conclusions are made;Planning and construction of forest roads have until very recently been geared towards establishment and tending of plantation forests. Now that most of the plantations are nearing maturity, it is essential to plan and construct proper roads for harvesting purposes. Hi is study was designed to develop a comprehensive methodology that can be used by forest managers in the planning and control of forest roads. Specifically, the objectives of the study were: - To evaluate the application of mathematical programming methods to the design of safe and minimum-cost forest roads - To test the feasibility of improving and controlling forest road construction by mathematical programming - To develop a comprehensive methodology for measuring and estimating production rates and costs associated with forest road construction. To be able to plan, execute and control work operations for this study, a representative 1.3 km access road was planned and constructed at the Training Forest of the Sokoine University of Agriculture between February 1981 and May 1984. A number of mathematical models and time study methods were tested and incorporated in this study in order to develop a comprehensive methodology aimed at improving plan ning, control and cost estimation procedures. Based on the results of this study, the following observatxons and conclusions are made;(a) With some modifications (in order to fit them to local conditions), the standard engineering procedures used for road design, layout and culvert size determination proved to be fully satisfactory for use in Tanzania. (b) Detailed time and work analyses conducted during the study resulted in the establishment of production rates and costs of forest road construction in Tanzania. (c) Microcomputer-based linear programming and a transportation tableau method were shown to be equivalent in determining optimal allocation of earthwork during forest road planning. Because it can be done by hand without recourse to a micro computer, however the transportation tableau method is the one likely to be favoured and adopted by most forest projects in Tanzania. (d) Before the actual road construction starts, the distance between net cut and net fill areas can be used as a surrogate for earthwork cost to determine the optimal road design. The study found that the design alternative selected on the basis of minimum earth moving distance was also the one that mini mized earthwork cost. (e) A distance of 30 m between instrument stations along the road appears to provide better accuracy for road layout and design than using either intervals of 60 m or utilizing "terrain breaks" to define instrument stations. In this study, both of these latter interval lengths provided data (a) With some modifications (in order to fit them to local conditions), the standard engineering procedures used for road design, layout and culvert size determination proved to be fully satisfactory for use in Tanzania. (b) Detailed time and work analyses conducted during the study resulted in the establishment of production rates and costs of forest road construction in Tanzania. (c) Microcomputer-based linear programming and a transportation tableau method were shown to be equivalent in determining optimal allocation of earthwork during forest road planning. Because it can be done by hand without recourse to a micro computer, however the transportation tableau method is the one likely to be favoured and adopted by most forest projects in Tanzania. (d) Before the actual road construction starts, the distance between net cut and net fill areas can be used as a surrogate for earthwork cost to determine the optimal road design. The study found that the design alternative selected on the basis of minimum earth moving distance was also the one that mini mized earthwork cost. (e) A distance of 30 m between instrument stations along the road appears to provide better accuracy for road layout and design than using either intervals of 60 m or utilizing "terrain breaks" to define instrument stations. In this study, both of these latter interval lengths provided data which tended to u. i erestimate actual road construction cost by about 30 Z. (f) The influence of road grade and alignment on log-truck haul ing speed can satisfactorily be determined through the prin ciples of engineering mechanics. For instance, when deter mining the hauling speed over a given road with a good number of sharp curves, time to decelerate into and accelerate out of the curve, the designed curve speed and the maximum safe speed have to be considered. (g) Of three road grade alternatives analysed in this study (6 Z, 8 Z and 10 Z), the 8 Z maximum grade recommended by the Forest Division was found to be the grade that minimized the total of earthwork and hauling costs. (h) The use of the critical path method during culvert installa tion resulted in the reduction of total installation time by about 28 Z. (i) Road construction is an expensive undertaking, but costs can be reduced to about 1/3 to 1/2 of those estimated by road contractors if proper applied. planning and control procedures are The construction cost of this research road was found to be shs 220 587/km, with earthwork and gravelling operations taking 33 Z and 30 Z of the total construction costs respectively, while road alignment/clearing and culvert installation took 24 Z and 13 Z respectively.In addition to these conclusions, the methodological procedures described in detail in this thesis provide a foundation on which forest managers can base decisions related to the planning and cons truction of forest roads.
Stakeholders' analysis and institutional performance in the use and management of Mangrove resources in the Rufiji delta, Tanzania
(Sokoine University of Agriculture, 2012) Kitula, R A
Mangrove ecosystem consists of several habitats, which attract numerous stakeholders with regard to utilization and management. However, information about stakeholders conflicting interests, institutional performance and types of resource-use conflicts over mangrove resources is inadequate. This study was designed to analyse stakeholders and institutional performance in the use and management of mangrove resources. The study was conducted in the Rufiji Delta and Floodplain. Socio-economic data were collected through Participatory Rural Appraisal approaches and household surveys. Ecological data were collected and analysed through Geographical Information System technique. Five logistic regression models were developed to analyse factors underlying institutional performance and resource-use conflicts. Sixteen areas of conflicting interests that occurred among stakeholders were identified which were rooted in institutional and socio-economic perspectives. Despite the shift in the management of mangrove forests from state control to participatory approach, mangroves were declining mainly as results of stakeholders conflicting interests. Also, the study showed that performance of Village Natural Resources Committees (VNRCs) and Mangrove Management Project (MMP) in governing mangrove forests was relatively poor. Factor constrained performances of VNRCs and MMP were residence duration, restrictions on harvesting mangrove resources, demand for resources, family size, poor coordination of stakeholders, illegal activities, unawareness of resource extinctions, inequity and perceived prolonged drought. Main resource-use conflicts were location, scale and tenure. Factors significantly increased conflicts of location include distance, unemployment and crop diseases. Conflicts of scale were significantly increased by desire for economic gains and age of a respondent. Factors including lack of extension contacts and awareness training significantly increased conflicts of tenure. Negotiation and mediation were two major mechanisms used in managing conflicts. In conclusion, most resource-use conflicts which arose fromoverlapping mandates were unresolved and mechanisms for their management were lacking. The study recommends the need for organising multi-sectoral forum after every two years for mitigating cross-sectoral conflicting interests to ensure sustainable management of mangrove resources.
Crown and root pruning of four year old boundary trees at Siaya and Nyabeda in Western Kenya: socio-economics, utilization of soil water, and maize and wood yields
(Sokoine University of Agriculture, 2004) Tefera, Almaz Tekleberhan
Farmers' survey and two field experiments were carried out at Siaya and Nyabeda in western Kenya to investigate the effect of crown and root pruning on tree growth. soil water dynamics, maize and wood yields, when trees are boundary planting along agricultural crops. The experiment carried out at Siaya included 4 years old trees of Casuarina equisetifolia. Eucalyptus grandis, Grevillea robusta and Markhamia hitea while the one carried out at Nyabeda involved 5 years old G. robusta. The following parameters were assessed over 5 and 4 cropping seasons at Siaya and Nyabeda respectively: tree growth, light interception, soil water dynamics, tree water uptake and maize yield. Results from the Siaya survey showed that 74% of the farmers grow M. hitea on their farms, which is an indigenous tree species in western Kenya. Eighty-four percent of the respondents observed that crop yields that are close to the trees were very low compared to crops that were far away from the trees. The result from the experimental data showed that all the four tree species in the test at both sites survived both heavy crown and root pruning without any mortality or reduced growth. Tree species showed significant (P<0.001) variability in branch biomass produced from crown pruning at Siaya site. Eucalyptus grandis had the highest biomass (107.2 kg/tree) production at the time of first pruning while M. lutea had the lowest (5.5 kg/tree). New branch sprouts of pruned trees continued to grow in both length and diameter. Eucalyptus grandis had the highest growth in both new branch length and basal diameter (10.49 m and 13.44 cm respectively) while M. lutea had the least (5.39 m and 6.75 cm respectively). Soil water under crown and root pruned trees were significantly (P<0.05) high compared to the unpruned (control) tree plots. Soil water content decreased by 25-35% under un-pruned (control) tree plots of all species as compared to soil water content under crown and root pruned tree plots. Transpiration of crown and crown plus root pruned C. equisetifolia and G. robusta trees was reduced by 50% as compared to unpruned trees. Maize grain yield was positively influenced by photosynthetically active radiation (PAR) under both C. equisetifolia (R2 = 0.84) and E. grandis (R2 = 0.97) boundary trees. During the first 3 maize cropping seasons, maize crops adjacent to pruned trees produced significantly (P<().01) higher yield (50-80%) compared to that growing adjacent to the unpruned (control) trees. Based on maize yield production, crown only pruning is recommended for M. lutea and E. grandis trees while crown plus root pruning is recommended for C. equisetifolia trees. Root only pruning is recommended for G. robusta trees. Trees of all species need to be re-pruned every 1-2 years.
The Eastern Arc mountain forests of Tanzania: their role in biodiversity, water resource conservation, and net contribution to atmospheric carbon
(North Carolina State University, 2001) Munishi, Pantaleo K. T.
Mountain forests play major ecological and environmental roles. This study evaluated the roles of the Eastern Arc Mountain forests of Tanzania in conservation of biodiversity, water resources, and net contribution to atmospheric carbon. The major objectives were three-fold: (1) the classification and description of plant community composition, diversity patterns, and their environmental correlates, (2) assessment of biomass and carbon pool in the phytomass and soils, (3) assessment of rainfall interception throughfall, stemflow, streamflow, and their correlation with rainfall. Data on vegetation, topography, soils, and hydrology were collected from the Usambara and Uluguru ranges. Using cluster analyses, Non-metric Multidimensional Scaling (NMS) ordination, and indicator species analyses, five different plant communities were identified on each range. These communities were associated with two topographic and fourteen edaphic factors. Elevation was the strongest correlate of community composition in individual ranges, followed by several edaphic factors. Landform index and soil sodium concentration [Na] play major roles in separating plant communities between different mountain ranges. The proportions of rare species were high raising a conservation concern as to whether this is evidence of species’ declines or a biological characteristic. The forests have tremendous capacity for C storage both in the phytomass (517 ± 17 t ha’1 in the Usambaras and 384 ± 10 t ha’1 in the Ulugurus), and in the soil (420 ± 100 t ha’1 in the Usambaras and 290 ± 53 t ha’1 in the Ulugurus). Phytomass C was higher in mid elevation communities while high elevation communities had higher soil carbon, and total carbon. Rainfall interception was 23% in the Usambaras and 20% in the Ulugurus. Throughfall was more than 76% in both forests and stemflow was less than 2%. Streamflow was best modeled using three or more months running mean rainfall. The results suggest that plant community patterns in the Eastern Arc are associated with a complex of topographic and edaphic factors. This complex of factors is an important consideration in restoration and conservation programs. Attention to rare species is especially important. The forests have substantial capacity for carbon emission mitigation. The slow response in streamflow to rainfall events shows the efficiency of the forests to store water, mitigate storm water impacts by reducing runoff, delaying onset of peak flows, and ensuring constant water supplies.
Optimising selected incentives for communities implementing joint forest management in catchment forest reserves in Uluguru and Udzungwa mountains, Tanzania
(Sokoine University of Agriculture, 2013) Sangeda, Anthony Zozimus
Some Catchment Forest Reserves (CFRs) in Tanzania are managed in collaboration between the government and communities through Joint Forest Management Agreements (JMAs). In CFRs, harvesting of timber is strictly prohibited. This has led to minimal incentives for communities. To readdress this, optimisation of honey and carbon were considered to serve compensation for the foregone timber benefits. The overall objective of the study was to examine means of optimising incentives for communities implementing Joint Forest Management (JFM) in CFRs. Two sites in Morogoro and Iringa regions were selected for the study. About 152 circular plots were sampled for ecological data which was analysed by Microsoft Excel. About 164 households were interviewed. Quantitative data was analysed using SPSS while the qualitative data were subjected to content analysis. Data for modeling were obtained within the ecological and socio-economic data sets and through rigorous literature review. Optimisation of incentives was done by Linear Programming using Microsoft Excel Solver. Stocking levels were higher in forests under JFM than forests without in both Iringa and Morogoro sites and the difference was statistically significant except in woodlands (p= 0.9049). FRs under JFM had slightly new disturbances than those without but the difference was not statistically significant (p=0.4752). The optimisation model revealed a return of USD 2 025 per year for Kimboza FR and USD 6 144 per year for NDU FR. Inclusion of illegally harvested wood in the model increased the profit to USD 29 286 per year for NDU FR. When labour was reduced, the profit further increased to USD 37 022 per year. These revenues were potential incentives for communities in forest conservation. Small returns in Kimboza were associated with small size of the forest (405 ha) which limited farther analysis from the model. Sensitivity analysis revealed that forest size between 615 and 1 536 ha gives a solution where both honey and carbon are optimally produced. It was concluded that, maximizing incentives through carbon storage in CFRs is worth in forests with more than 615 ha. Therefore, care need to be taken during selection of CFRs to be included in JFM regime.
Land use allocation between forestry plantations and food crop production in selected villages in Mufindi district, Tanzania
(Sokoine University of Agriculture, 2021) Sauth, Ng’elenge Haji
The increasing population and income have raised the demand for timber and other wood products, hence opening a new economic opportunity in addition to the production of food crops by smallholder farmers in Mufindi District and the Southern Highlands of Tanzania in general. Farmers require information on the optimal land allocation for various farm enterprises to make the best use of their land. However, such information is missing in the study area. Therefore, the determination of optimum land use allocation between tree plantations and food crops is vital for increased earnings, food security, and improved livelihoods of smallholder farmers. Worldwide, studies have mainly focused on optimization problems involving annual food crops only, while in reality, there are farmers allocating land to both food crops and forestry plantations, and that, there is limited knowledge on the optimal land allocation for farmers in the study area who allocate their land to both food crops and forestry. This study, therefore, aimed to establish the optimal land-use allocation between forestry plantations and production of food crops in selected villages in Mufindi District, and was guided by three objectives; (i) identifying the food crops/tree plantation combination that maximizes smallholder farm profit; (ii) exploring the determinants of land use allocation decision in food crops-tree production; and (iii) assessment of food security status by Smallholder Famers’ in selected Villages in Mufindi District. A multistage sampling technique was adopted in the sampling process. The first stage involved the selection of three divisions from the District based on their potential in food crops and tree production. It was followed by a purposive selection of eight villages both potential in food crops/tree growing in each division, and finally, a random sampling technique was used to select 413 households. A multi-period profit maximization programming model was used to analyze the study objective one; while objective two was analyzed by using fractional multinomial logit model (FMNL), and the Households Foodiii Access Scale approach (HFIAS) was used in the analysis of the third objective. Major results showed that a farmer can maximize profit by allocating 1.81 and 1.74 acres to round potatoes and pine trees respectively, to generate a maximum profit of 13 592 440.53 while also allocating about 0.57 and 0.35 acres for maize and beans respectively to meet family food requirements. Moreover, the results showed that capital and land are binding in the study area. Results from fractional multinomial logit showed that sex, land size, awareness of land use policy, access to market information, and availability of labour play an important role in determining land allocation decisions to tree production, fallow, and food crops. On average households tended to allocate 4.28 acres to tree plantations, 3.57 acres to food crops, and 0.39 acres to fallow Moreover, overall results on food security as measured by Household Food Insecurity Access Scale (HFIAS) showed that 23% of all households were food secure, 9.7% mildly food insecure, 59.8% moderately food insecure and 7.5% severely food insecure. From the study results, it can be generally concluded that farmers can maximize farm profit by allocating 1.74 acres to pine trees and 1.81 acres to round potatoes while also allocating 0.57 and 0.35 acres to maize and beans to meet subsistence households’ consumption. Also, land size, access to agricultural market information on output prices, awareness of land use policy; and availability of farm labour are the major determinants of land allocation decisions. Moreover, income from tree plantations was found to contribute a big portion to the household income than other sources. However, as income from tree plantations becomes available after several years, production of both food crops and tree plantations is essential for ensured food security at both the household and national levels. Hence the study recommends that farmers should acquire more land either through purchasing or hiring to allocate more on trees and round potatoes for increased income and profit and hence improved household food security. Also, the creation of more off-farm activities from the forestry farming sector, to absorbiv the excess labour. This, in turn, increases income hence improving household food security and better living. From the government's perspective, the government should provide low-interest credits to enable farmers to invest more hence increased income and improved households’ food security; also, the government should improve its agricultural information system through the use of agricultural extension agents and media. This in turn will enhance more land allocation to trees and round potatoes
The regeneration of miombo woodlands in charcoal production areas in kilosa district, Tanzania
(SUA, 2021) Godbless, Stanley Matowo
Miombo woodlands covers 90% of the forested area in Tanzania and 10% of the African landmass. Therefore, any deforestation or forest degradation of these forests have the national and continental significance. The ability of miombo to regenerate naturally functions as the survival mechanism amongst multiple disturbances. The majority of disturbances to miombo woodlands have been imposed by humans in meeting their demands for survival. This includes the disturbance generated in obtaining the fuelwood. Charcoal is used as an important fuelwood to both urban and rural populations. However, charcoal production is considered as the massive cause of deforestation and forest degradation in Tanzania and across the continent. Regarding the importance of charcoal to the society, Sustainable Forest Management (SFM) to ensure the sustained production of charcoal is requisite. The present study aimed to provide a better understanding of regeneration of miombo trees through the assessment of the area deliberately harvested for charcoal production. The study was conducted in eight Village Land Forest Reserves (VLFRs) in Kilosa district under Community Based Forest Management (CBFM). Specifically, the study aimed to (i) review literature on regeneration dynamics of miombo trees, (ii) assess the regeneration status of miombo trees in the charcoal kiln scars, (iii) assess the forest standing structure and above-ground biomass in harvested blocks and (iv) determine the optimum stump height and diameter for maximum coppicing in harvested miombo. Data collection utilized different methods and sampling approaches. For the first objective, a standard literature search for documents related to miombo regeneration was performed using multiple electronic databases. More than 60 peer-reviewed published papers on the subject matter were obtained and critically reviewed. The data for the second objective was obtained by assessing the kiln scars in charcoal production blocks. The assessed blocks were only those with 4, 5 and 6 years from cessation of charcoal production where 154 kiln scars were assessed. The third objective aimed to assess the standing structure and above-ground biomass, where 106 circular plots with a radius of 15 m were assessed in the areas where charcoal production has ceased for 6 years. In the fourth objective which aimed on establishing the optimum stump height and diameter for maximization of coppicing regeneration in the areas harvested for charcoal production, the assessment was done to stumps within the plot of 50 m x 50 m. A total of 925 stumps, representing 43 species were measured in the area with 4 (2015-2019), 5 (2014 - 2019) and 6 (2013 - 2019) years from cessation of charcoal production. The stump height, stump diameter, regenerants counts and size (basal diameter and height) were measured, alongside identifying species for individual stumps. The results revealed that vegetative propagation through coppice and root suckers are the most feasible and prominent regeneration method in miombo woodlands managed for charcoal production. Kiln scar results revealed that kiln scars occupy 1.5% of the total harvested area. The study also confirmed that trees can naturally regenerate in kiln scars to which the number of tree regenerants increases significantly (F (2,151) = 7.1, p < 0.05) with the addition of time from cessation of charcoal production. Assessment of standing structure and composition of 6 years post charcoal production cessation recorded stand dominated by re-growing trees with the basal area, volume and above-ground biomass of 3.77 ± 1.27m 2 ha -1 , 31.71 ± 10.79m 3 ha -1 and 21.5 ± 7.24t ha -1 , respectively. Also in the harvested area, about 68% of trees were established from seedlings with remaining individuals established vegetatively as they were limited to the number of stumps remained. The assessment of stumps for coppicing revealed that number of living stumps decreased significantly (p < 0.05) with the increase in time where 73, 68 and 51% of stumps were alive in the area terminated harvesting for 4, 5 and 6 years, respectively. Also, there is a positive relationship between the stump mortality and the increase of the stump diameter while no clear pattern for stump height. The coppicing effectiveness of the stump increases with both diameter (r 2 = 0.31) and height (r 2 = 0.18). The optimum harvesting diameter and height ranges is from 20 to 40 cm and 45 to 60 cm, respectively. Generally, it is concluded that trees in harvested charcoal production areas are regenerating naturally and growing relatively well. Also, vegetative propagation through stump coppices and root suckers is the most feasible and suitable regeneration method in management of forest harvested for charcoal production. The coppicing effectiveness is determined by stump height, stump diameter and the time lapsed from harvesting. Harvested large diameter trees are associated with high mortality compared to small- diameter trees. The high stump survival was recorded for stumps with height between 46 and 60 compared to higher mortality of shorter and longer stumps. To reduce the recovery time of the harvested stand, it is recommended that the minimum harvesting dimensions should be revised to stump diameter between 20 and 40cm and height between 45 an 60cm. Also, the protection of regenerating areas against disturbances is highly recommended since its recovery largely depends on the seedlings which are highly vulnerable to the effects of disturbances such as fire and overgrazing.
Monitoring of woody plant species composition, diversity, structure and dynamics in kihansi gorge forest, southern Udzungwa mountains, Tanzania
(sokoine university of agriculture, 2021) Ubisimbal, Jeswald Gustav
Kihansi Gorge forest is located within the Udzungwa Mountains in the Eastern Arc Mountains in Tanzania. The Gorge has critically endangered and endemic plant species, hence has national and global significance. Kihansi hydropower project started to be constructed in 1990 and its operation commenced in 1999. The construction of the hydropower facilitated the establishment of baseline study to monitor the forest. The main objective of this study was to monitor trees’ diversity using the established baseline study. Specifically this study intends (i) To assess changes of woody plant species composition and diversity for the period between 1997 and 2018 (ii) To assess changes in forest stand parameters between 1997 and 2018 (iii) To assess changes in tree species diversity and forest stand parameters along altitudinal gradients. Data were collected in 19 permanent sample plots established in year 1997 and 75 temporary sample plots installed in year 2018. The findings from statistical tests for all stand parameters for montane forest showed no significant differences (p > 0.05) throughout the study period. Basal area, volume and total carbon for miombo showed a significant difference (p < 0.05) for year 2006 and year 2009 and no significant difference (p > 0.05) for the year 2018. The study concludes that time to detect significant changes of forest stand parameters differ between vegetation types. Dynamic processes in the miombo woodlands are faster compared to montane forest. Based on altitude, tree species diversity in the Kihansi Gorge forest decreases as altitude increases. The study recommends monitoring to continue at Kihansi Gorge forest through the established permanent sample plots to ascertain the causes of the changes.
Institutions, governance, and upgrading in non-industrial private forestry value chain in the Southern Highlands of Tanzania
(Sokoine University of Agriculture, 2021) Martin, Respikius
Among the factors for the rise of Non-industrial private forestry (NIPF) include, the demand for timber and limited capacity of governments and corporations to supply to cover for the deficit. In developing countries, NIPF is dominated by smallholder farmers and presents a huge potential for alleviating poverty in rural areas where the majority of farmers live. Nevertheless, institutional framework and governance of the NIPF value chain have a huge influence on the benefits accrued from NIF and their distribution. However, in Tanzania, most studies on the role of institutional framework and governance have been on natural forests and industrial plantations, which for a long time have been the main source of timber in the country. Using the theory of access and the global value chain, particularly the institutional framework and governance structure dimensions, the study analyzed the role of institutions and governance in non-industrial private forestry value chain in the Southern Highlands of Tanzania. Specifically, the study intended to 1) analyze the role of state regulations in governing timber value chain 2) examine the role of informal institutions in timber value chain and 3) analyze the types of upgrading in the NIPF value chain and the institutions driving them. In large measure, the study adopted an exploratory cross-sectional study design whereby qualitative data were collected through in-depth interviews, focus group discussions, observations and document reviews. In addition, quantitative data were collected for the study from six district councils in Njombe and Iringa regions. Qualitative data were analyzed following six steps of thematic analysis including transcribing interviews into text, going through the text, coding the text, grouping the codes to form themes, reviewing the themes, describing the themes and assessing their relationships. SPSS software was used for analyzing quantitative data. The study findings show that the government is the sole regulator of the NIPF value chain, and all actors in the chain operate under the same regulatory framework. This was not unique as similar cases are found in many developing countries. However, in Tanzania, regulations are implemented differently at the district council level whereby some district councils, unlike others, charge higher the cess per a piece of timber. Lack of distinction between industrial and non-industrial private forestry has resulted in placing industrial and non-industrial forestry under the same regulatory framework despite their many differences including economic status of the owners, the size of plantations, and management plans. Lack of distinction has also partly resulted in high transaction costs, which are unaffordable to the majority of actors in the NIPF value chain. Although the regulations affect incomes of all actors, tree growers are the most-affected category. Besides, the study found that trust between value chain actors played a role of integrating actors in the value chain. However, in some instances, it also excluded some actors from accessing timber market under the guise of lacking or having low level of trust. Furthermore, the study found that institutional framework comprising the government, development partners through donor-funded programmes, and grower organizations are behind attempts to upgrade the NIPF. Although four types of upgrading are promoted, only functional upgrading was found to have resulted into higher income among tree growers. In view of the study findings, it is concluded that although forest regulations were set to facilitate the operations of NIPF and to improve its contribution to rural livelihoods. Some of the regulations have resulted into unintended negative effects by limiting the actors of the value chain from gaining more income. Similarly, informal institutions, particularly trust, play an important role of integrating actors in the value chain by enabling them access regional market. Besides, the study concludes that in the absence of a lead firm, upgrading driven by institutions comprising the government, development partners through donor funded programmes, and grower organization is still occurring. The study recommends that in order for NIPFs to contribute significantly to the income of actors, the government, through the Ministry of Natural Resources and Tourism (MNRT), should review the regulations governing the timber value chain. Specifically, barriers that limit tree growers and other actors from gaining access to the markets should be minimized or completely removed. In addition, in order for upgrading strategies to contribute to the improvement of rural livelihoods in the Southern Highlands of Tanzania, institutions promoting upgrading in NIPF value chain should pay attention to the needs of the tree growers.
The regeneration of miombo woodlands in charcoal Production areas in Kilosa district, Tanzania
(Sokoine University of Agriculture, 2021) Matowo, Godbless Stanley
Miombo woodlands covers 90% of the forested area in Tanzania and 10% of the African landmass. Therefore, any deforestation or forest degradation of these forests have the national and continental significance. The ability of miombo to regenerate naturally functions as the survival mechanism amongst multiple disturbances. The majority of disturbances to miombo woodlands have been imposed by humans in meeting their demands for survival. This includes the disturbance generated in obtaining the fuelwood. Charcoal is used as an important fuelwood to both urban and rural populations. However, charcoal production is considered as the massive cause of deforestation and forest degradation in Tanzania and across the continent. Regarding the importance of charcoal to the society, Sustainable Forest Management (SFM) to ensure the sustained production of charcoal is requisite. The present study aimed to provide a better understanding of regeneration of miombo trees through the assessment of the area deliberately harvested for charcoal production. The study was conducted in eight Village Land Forest Reserves (VLFRs) in Kilosa district under Community Based Forest Management (CBFM). Specifically, the study aimed to (i) review literature on regeneration dynamics of miombo trees, (ii) assess the regeneration status of miombo trees in the charcoal kiln scars, (iii) assess the forest standing structure and above-ground biomass in harvested blocks and (iv) determine the optimum stump height and diameter for maximum coppicing in harvested miombo. Data collection utilized different methods and sampling approaches. For the first objective, a standard literature search for documents related to miombo regeneration was performed using multiple electronic databases. More than 60 peer-reviewed published papers on the subject matter were obtained and critically reviewed. The data for the second objective was obtained by assessing the kiln scars in charcoal production blocks. The assessed blocks were only those with 4, 5 and 6 years from cessation of charcoal production where 154 kiln scars were assessed. The third objective aimed to assess the standing structure and above-ground biomass, where 106 circular plots with a radius of 15 m were assessed in the areas where charcoal production has ceased for 6 years. In the fourth objective which aimed on establishing the optimum stump height and diameter for maximization of coppicing regeneration in the areas harvested for charcoal production, the assessment was done to stumps within the plot of 50 m x 50 m. A total of 925 stumps, representing 43 species were measured in the area with 4 (2015-2019), 5 (2014 - 2019) and 6 (2013 - 2019) years from cessation of charcoal production. The stump height, stump diameter, regenerants counts and size (basal diameter and height) were measured, alongside identifying species for individual stumps. The results revealed that vegetative propagation through coppice and root suckers are the most feasible and prominent regeneration method in miombo woodlands managed for charcoal production. Kiln scar results revealed that kiln scars occupy 1.5% of the total harvested area. The study also confirmed that trees can naturally regenerate in kiln scars to which the number of tree regenerants increases significantly (F (2,151) = 7.1, p < 0.05) with the addition of time from cessation of charcoal production. Assessment of standing structure and composition of 6 years post charcoal production cessation recorded stand dominated by re-growing trees with the basal area, volume and above-ground biomass of 3.77 ± 1.27m 2 ha -1 , 31.71 ± 10.79m 3 ha -1 and 21.5 ± 7.24t ha -1 , respectively. Also in the harvested area, about 68% of trees were established from seedlings with remaining individuals established vegetatively as they were limited to the number of stumps remained. The assessment of stumps for coppicing revealed that number of living stumps decreased significantly (p < 0.05) with the increase in time where 73, 68 and 51% of stumps were alive in the area terminated harvesting for 4, 5 and 6 years, respectively. Also, there is a positive relationship between the stump mortality and the increase of the stump diameter while no clear pattern for stump height. The coppicing effectiveness of the stump increases with both diameter (r 2 = 0.31) and height (r 2 = 0.18). The optimum harvesting diameter and height ranges is from 20 to 40 cm and 45 to 60 cm, respectively. Generally, it is concluded that trees in harvested charcoal production areas are regenerating naturally and growing relatively well. Also, vegetative propagation through stump coppices and root suckers is the most feasible and suitable regeneration method in management of forest harvested for charcoal production. The coppicing effectiveness is determined by stump height, stump diameter and the time lapsed from harvesting. Harvested large diameter trees are associated with high mortality compared to small- diameter trees. The high stump survival was recorded for stumps with height between 46 and 60 compared to higher mortality of shorter and longer stumps. To reduce the recovery time of the harvested stand, it is recommended that the minimum harvesting dimensions should be revised to stump diameter between 20 and 40cm and height between 45 an 60cm. Also, the protection of regenerating areas against disturbances is highly recommended since its recovery largely depends on the seedlings which are highly vulnerable to the effects of disturbances such as fire and overgrazing.
Assessment of implementation of village land use plans in Ulanga district, Tanzania
(sokoine university of agriculture, 2019) Naiposha, M. N.
Land use plans have been considered as a solution to land use problems. Existing studies have reported cases of non-adherence to the plan though limitedly considered assessing their implementation at village level. Implementation of the land use plan relies on how sufficient are the allocated land use zones, if the land use groups adhere to the plan and whether the available strategies enhance adherence to the land use plan. This study was designed to empirically identify land use implementation problems and suggest solutions relevant to the land users, the government, planners and other stakeholders. Primary data were collected through household survey of 120 respondents from two villages, key informants, focus group discussions and field observation survey while secondary data were collected through review of guidelines for land use planning, village land use plans, district land use framework, books and journals. Information used to assess sufficiency of land use zones and strategies used in Village Land Use Plan (VLUP) from household survey and village records were descriptively analysed. GPS points to examine adherence to VLUPs were analysed using Kappa statistic. Factors influencing adherence to VLUPs were analysed using binary logistical regression and pair-wise ranking. Findings showed that the allocated zones were insufficient for the current and future needs whereby 90% of the respondents declared insufficiency of the allocated zones. Discrepancies were noted in the size of land in the VLUP document and those digitised via Arcview GIS. Kappa analysis resulted to moderate adherence with kappa coefficient of 0.47 and 0.49 for Iragua and Kichangani villages. Corruption of village leaders, failure of village leaders to implement, lack of awareness on land use plans and increased population were the key prioritised factors that affected adherence to land use plans. The study recommends a review of the zoning standards to enhance sufficiency of allocated zones; privatization of grazing land; establishment of communal grazing management plans; and involvement of communities in developing complete plans. The study also recommends close monitoring; reviewing of VLUPs; enforcement of good governance; establishing incentive schemes; offering continuous education and awareness, and developing participatory implementation framework with clearly stipulated roles, strategies, milestones and indicators as well as resource mobilisation strategy.
Factors affecting pine resin productivity and its potential as source of revenue in the forest sector of Tanzania: a case study of Sao Hill Forest Plantation
(Sokoine University of Agriculture, 2019) Salim, B. S.
Tanzania is rich in pine forests which have the potential to produce valuable resin. In recent years Tanzania has embarked on commercial resin tapping at Sao Hill Forest Plantation. However, current information on resin tapping in the country is scanty and unreliable. Knowledge of factors that affect resin productivity is important for it is those factors that can be manipulated to enhance resin yield. The focus of this study was to fill this knowledge gap by exploring some pine tree stands in terms of capacity to produce resin, factors that influence productivity, optimum age of commencing resin tapping and finally the potential revenue gain from tapped trees. Two-stage sampling was used to obtain estimates of tree characteristics and resin yield by first selecting seven representative compartments. In the second stage, 21 sample plots of dimensions 12 x 12 m were systematically established, 3 in each compartment. All trees in each plot were measured for diameter at breast height (dbh). In addition, total height, stem height and crown size of the smallest, medium and largest trees were measured. All trees in a plot were tapped for resin. Dilute sulphuric acid (40%) was sprayed to the wounded part of stem to stimulate and maintain resin flow. Recording of resin weight and re wounding of trees were done after a minimum period of every ten days in ten sessions from October 2018 to January 2019. Annual resin yield ranged from 0.56 kg/tree to 1.32 kg/tree for P. elliottii and from 0.47 kg/ tree to 1.98 kg/ tree for P. patula. Dbh and crown diameter were found to be important predictors of resin at tree level while yield per ha could well be predicted using stand variables in particular age, volume and basal area per ha. The recommended minimum dbh for resin tapping is 20 cm while 15 years could be used as minimum age to commence tapping. TZS 4 589 884 350 can be raised annually through resin tapping from 2 618 568 mature trees in state owned plantations. Results of this study will be useful to pine tree stakeholders in realizing income while waiting for the conventional rotation age for timber harvesting. Further research on effect of resin tapping on tree growth and wood quality can be very useful to tree growers.

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