Articles, Conference and Workshop Papers Collection

Permanent URI for this collectionhttp://10.10.97.169:4000/handle/123456789/59

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Resource use efficiency in beekeeping using modern beehives: a case of Sikonge district, Tabora - Tanzania
(Tanzania Journal of Forestry and Nature Conservation, 2022) Wawa, M.M.; Lusambo, L.P.; Mbeyale, G.E
This study revealed detailed information concerning resource use efficiencies using modern beehives essential in planning to improve yield and profit of beekeeping in Sikonge District. Choices made by a beekeeper to use what and how much resources in beekeeping vary among beekeepers basing on availability of the resource itself. This study analysed the resource use efficiency in beekeeping activities in Sikonge District. The specific objective for this study was to evaluate resource use efficiency of beekeeping using modern beehives. Data was collected by semi-structured questionnaire, key informants’ interview, focus group discussion and direct field observation. This study was done in four wards; Chabutwa, Tutuo, Kipanga and Kiloleli. The wards were randomly selected out of the 15 wards of Sikonge District. Descriptive statistics were obtained using Statistical Package for Social Science (SPSS) computer programme as analytical tool. Results revealed that the number of beehives and number of man-days for hired labour were underutilised with resource use efficiency coefficient (r) values of 1.5 and 121 respectively while family labour man-days were over utilised (r = - 91.82). It is recommended that beekeepers in Sikonge utilize the available resources optimally to maximize yield and profit of their beekeeping activities.
Learn by doing: modelling the effect of training and job interruptions on tree cutting time for chainsaw operators in plantation forests, Tanzania
(2014-11) Silayo, Dos Santos A.; Migunga, George A; Shemwetta, Dunstan T. K.
Timber harvesting in Tanzania uses semi-mechanized and labour – intensive logging systems. Manual or semi- mechanized logging operations by using hand tools are more favoured due to cheap labour availability. For example, tree cutting is done manually using two-man crosscut saws, axes or chainsaws. This study was conducted at Sokoine University of Agriculture Training Forest to assess the effect of training and job interruptions for chainsaw operators during tree cutting operations in softwood plantation forests in Tanzania. Tree cutting operations using experienced and inexperienced chainsaw operators were studied in three experiments; before training, after training and after the break. Time study and work sampling techniques were used for data collection. Descriptive statistics and modeling was performed for each crews’ performance. Results show that generally, experienced crew spends lesser time in cutting as compared to inexperienced crews. However, start up chainsaw crew spent 32% higher time for preparation before tree felling. However, the crew showed significant improvement after training unlike the experienced one. The analysis of the delay times start up crew was had a significant proportion of the delay times during the first engagement which decreased substantially in the other two experiments. Generally, there was an improvement of the cutting time after training for all crew categories with decrease after the break. This observation signifies that job interruptions impact the productivity of the crews. Therefore, on job training on resumption of the operations may significantly improve crews’ productivity, safety as well as ensuring product quality.
Identifying ecosystem service hotspots for targeting land degradation neutrality investments in south-eastern Africa
(Elsevier, 2017-05) Willemen, L; Crossman, N.D; Quatrini, S; Egoh, B; Kalaba, F.K; Mbilinyi, B; Groot, R.d
Land degradation response actions need motivated stakeholders and investments to improve land management. In this study we present methods to prioritise locations for degradation mitigation investments based on stakeholder preferences for ecosystem services. We combine participatory and spatial modelling approaches and apply these for Zambia, South Africa, and Tanzania to: i) prioritise ecosystem services in each country; ii) to map the supply of these ecosystem services in each country, and; iii) prioritise areas important for investment for the continuous delivery of these ecosystem services based on their vulnerability to land degradation. We interviewed 31 stakeholders from governmental and non-governmental organizations to select the most important ecosystem services per county. Stakeholders were also asked to indicate on national maps the hotspots of these ecosystem services and locations with a high degradation risk. We then assessed the supply of the stakeholder-selected ecosystem services and land degradation risk using GIS-based spatial models. We found that for each country the spatial extent and magnitude of ecosystem services supply and land degradation based on GIS data coincides with stakeholder knowledge in some locations. In the context of supporting national level policy to achieve land degradation neutrality as proposed by the United Nations Convention to Combat Desertification we argue that the correct representation, the level of acceptance, and use of modelled outputs to support decisions will be greater when model outputs are corroborated by stakeholder knowledge. Ecosystem services that are identified as “important” by diverse stakeholder groups have a broader level of awareness and could therefore drive motivations, commitments, and actions towards improved land management, contributing to land degradation neutrality.
Critique of decentralized political structures in water resource management in Tanzania: the case of Pangani river basin
(WIT PRESS, 2011-05) Olemako, T. R; Munishi, P. K. T; Kadigi, R. M. J
Tanzania adopted the river basin model in 1950s and declared it as an essential feature for economic development. Since 1990 management of water resources in Tanzania is based on the nine river basins that do not follow administrative boundaries as defined under the system of decentralized political structures. Water is a key resource in the river basin; however, it is not a driver of economic development. Drivers of economic development are outside the water sector such as energy, agriculture and mining. The non-water sectors fall under decentralized political structures from the central government ministries, regional administration to local government authorities. The system of political structures cut across different varieties of governance from central to local government levels. Variance in governance under these structures has intensified water scarcity and as an institutional and legal tool is more rhetorical rather than practical. Total water withdrawal in Tanzania is estimated to be 5,142 million m 3 out of which agriculture development consumes more than 85% and the rest accounts for the domestic sector, livestock development and industry. Water scarcity hinders the effectiveness of the adopted river basin model as competition of water use between hydropower production and irrigation is intense. This paper addresses the main questions as to what effectsthese structures have on institutional policy design and discourse in the river basin management. Do the structures promote or block institutional reforms? How is the sustainability of the reforms ensured? This paper suggests a mainstream institutional set up of a non-water sector into the river basin model from the central to local government levels.
Insects feeding on Sesbania species in natural stands and agroforestry systems in southern Malawi
(Kluwer Academic, 2012-04) Sileshi, G.; Maghembe, J. A; Rao, M. R; Ogol, C. K. P. O; Sithanantham, S.
Pest and disease interactions in agroforestry systemsis a little studied area.Surveys were conducted in the Mangochi and Zomba districts of southern Malawi between December 1997 and February 1998 to identify insects feeding on Sesbania species in natural stands and in agroforestry systems at the research station and on farms, and the host range of the insects. Out of a total of 30 insect species recorded in natural stands, Brachyplatys testudonigro, Mesoplatys ochroptera, Exosoma sp. and Ootheca sp. were the most commonly found insects feeding on S. sesban. Afrius figuratus, Glypsus conspicuus, Macrorhaphis acuta, Mecosoma mensor, Rhinocoris segmentarius and Cyaneodinodes faciger were recorded for the first time as natural enemies of Mesoplatys ochroptera in Malawi. The defoliating beetles, M. ochroptera, Exosoma sp. and Ootheca sp., were the most frequently found insects infesting S. sesban on farms. M. ochroptera attacked only Sesbania species, and usually higher populations of this beetle were recorded on annual Sesbania species (S. tetraptera, S. bispinosa, S. leptocarpa and S. sericea) than on perennial types. Although the sap-sucking bug, B. testudonigro, was relatively less common on sesbania on farms, it has been found to infest a number of other legumes of the genera Aeschynomene, Crotalaria, Desmodium, Indigofera, Mucuna, Phaseolus, Tephrosia and Vigna. Given the wide variety of plant species it attacks, B. testudonigro may become a potential pest of many agroforestry tree species. The insects Anoplocnemis curvipes, Aphis fabae, Hilda patruelis, Megaleurothrips sjostedti, Mylabris dicincta, Nezara viridula and Ootheca sp. also have the potential to become pests of agroforestry systems, as they can damage many agroforestry trees, including Sesbania, and crops. There is a need to study the biology and ecology of potential insect pests of S. sesban to plan for their integrated management in agroforestry.
Market signals of unsustainable and inequitable forest extraction: assessing the value of illegal timber trade in the Eastern Arc mountains of Tanzania
(Elsevier, 2014) Schaafsma, M; Burgess, N. D; Swetnam, R. D; Ngaga, Y. M; Treue, T; Turner, R. K
Natural forests and woodlands of the Eastern Arc Mountains (EAM) in Tanzania are under threat from deforestation and degradation. The estimated annual revenues from EAM hardwood for domestic use are USD 10 million in terms of planks, and twice as much when processed into furniture. Timber profits are largely captured by people whose livelihoods do not directly depend on other EAM ecosystem services. Market data, such as declining plank sizes and shifts to low-quality timber species, contain possible early warning signals of unsustainable hardwood harvesting. Policy recommendations include simplifying regulations for legal trade, developing sustainable financing, and increasing softwood supply.
Stump diameter : a potential predictor of removed biomass through tree cutting
(Tanzania Journal of Forestry and Nature Conservation, 2021) Mugasha, W.A; Mauya, E; Karlsson, K; Malimbwi, R.E.
Stump diameter (SD) has been rarely considered as an important tree parameter in forestry. It is until recently that SD has been found to be important predictor of tree diameter at breast height (D) and forest stand parameter such as volume and biomass. This study, developed D-SD relationships for nine different forest cover type in Tanzania mainland. A total of 32265 sample trees covering miombo woodlands, humid montane, lowland forests, bushlands, grasslands, mangroves, cultivated land, wetlands forests and plantations (Pines and Eucalyptus species) were used for fitting D-SD models. The findings revealed a linear relationship between D and SD for all forest covers. In addition, we found forest covers having similar D-SD allometry while others had unique D-SD allometry. This prompted fitting Generalised Linear Model where three forest cover groups were generated, i.e. group 1 (bushlands, woodlands, lowlands and grasslands); group 2 (mangroves, cultivated land, plantation and wetlands); and group 3 (humid montane). We fitted linear model to each forest cover group. Large variations in D were adequately explained by SD for each forest cover group. We further compared AGB values estimated from the measured D and estimated D from the D-SD equation. The estimated AGB from both approach did not differ significantly. We therefore, recommend the developed D-SD relationships models be applied to predict D of the missing trees for which their stumps still exist.
The influence of logging and animal grazing on the litter layer and water infiltration rate of soils in plantation forests
(Journal of Tropical Forest Scienc, 1999) Abeli, W. S.; Sawe, C. T.
The influence of logging and animal grazing on the litter layer and water infiltration rate of soils in plantation forests. Investigations to show the extent of soil disturbance caused by logging and animal grazing were carried out in one of the forest plantations in Tanzania. Water infiltration capacity and ground litter thickness were used as a measure to determine the extent of soil disturbance. Data on infiltration rate and litter depth on stands under different management practices were collected, analysed and compared with data from the nearby undis- turbed natural forests. The study found that logging and animal grazing reduced water infiltration rate in the soil and deposition of ground litter. Depending on the management practice or the condition of the stand, the rate of water infiltration was reduced from 36 to 96% when compared to water infiltration rate experienced in the nearby natural forest. While in undisturbed natural forest the mean litter depth was 11.1 cm, on clearfelled and grazed stands, the litter depth was only 0.9 cm. The effects of low water infiltration rates and low litter deposition are discussed and measures aimed at increasing water infiltration rate and litter deposition are suggested.
Comparing Productivity and Costs of Three Subgrading Machines
(1993) Abeli, W.S.
Production rates and costs of three forest road construction machines (Ford County 1164 tractor, D4D and D6D Caterpillar bulldozers) were analysed and compared. Results showed that differences in production rates were attributed mainly by the type and the size of the machine, driver's working experience and the nature of the terrain side slope. Compared to other subgrade productivity studies, machine production rates found in this study were considered to be reasonably high. The mean production rates for the D6D, D4D and the County tractor were 129.0 m3/h, 41.0 mVh and 28.1 mVh respectively. High productive time, easily workable soils and few obstacles encountered during earthworks operation were the major factors which contributed to high machine production rates. Cost analysis showed that the higher the machine production rate the lower the subgrading cost and vice versa. The mean production costs for the D6D, D4D and the County were estimated to be US$ 0.49/m3, US$0.79/m3 and US$0.76 /m3 respectively. The estimated machine production costs were more or less the same as those estimated elsewhere. Although low machine production cost is usually the criterion used in choosing the machine to be used for road construction works, this paper recommends that other factors be considered.
Optimal road spacing for manual skidding sulkies
(Forest Research Institute Malaysia, 1993-09) Abeli, W. S.; Magomu, G. M.
An optimal road spacing is the one which minimizes the overall sum of skidding costs, road construction and road maintenance costs. As road spacing increases, skidding cost increases while road construction and maintenance cost decreases. Each skidding means has its own optimal skidding distance and road spacing. This study analyses skidding productions and optimal road spacing for hand sulkies skidding logs in one of the forest plantations in Tanzania. Results from this study indicate that when undertaking thinning operations especially in flat to gentle sloping terrains, sulky skidding could be considered as a better alternative to tractor and manual skidding methods. Besides being simple and cheap, the system causes minimum stand and soil damages, creates employment opportunities for the rural people and does not demand foreign capital .The average skidding distance in this study was measured to be 71 m while average skidding production was estimated to be 1.21 m3/man-hour. An optimal road spacing which minimizes the overall total costs in this forest was found to be 137 m.
Socio-economic impact of ox skidding project to the surrounding villages of Mount Meru forest plantations, Northern Tanzania
(Southern African Forestry Journal, 2012-05-09) Abeli, W. S.; Maximillian, J. R.; Kweka, A. E.; Shemwetta, D. T. K.
The ox skidding project was initiated with the objective ofusing oxen for transporting logs from the stump sites to the landings. Itwas supposed to be a participatory research project aimed at integrating scientific knowledge with practical skills and resource base ofthe local farmers. Specifically the main objective of the project was to encourage local farmers (villagers) to use their animals to skid logs in the surrounding forest plantations in order to improve their incomes and create employment opportunities to the surrounding communities especially the youth. A socio-economic survey was carried out after 6 years to assess the impact ofthe project to the oxowners who have been participatingin the project, the oxhandlers, the surrounding villages and the forest plantations. Data was collected through administering semistructured questionnaires to ox owners, village leaders, ox handlers and the management of the forest plantations. Results indicate that the ox skidding project has been a reliable andvaluable source ofincome besides offering employment to young people with only limited education. The project has improved the household income, life style and standard ofliving ofsome farmers and above all, changed the local peoples' attitudes towards the importance of the surrounding forest resources. Most of the local people feel that they are now part of the surrounding forests as they participate to some extent in the management and protection ofthese forest resources. The project has in addition created awareness among the community that oxen can also be used in forest operations besides undertaking agricultural activities. The project found that given the operating conditions of the skidding tractors in this area, ox skidding was more reliable and more cost effective than the tractor skidding system. Through this project, it has been possible to improve the workingrelationships between the surroundlngvillagesandforest plantations management. The projecthas also led to some ofthe surroundingvillages establishing village environmental committees, which work very closely with forest plantation management. The sustainability of the ox skidding system introduced in this area is likely to continue since farmers surrounding these plantations keep cattle and there are not many alternative job opportunities for the young people.
Tanzanian rangelands in a changing climate: impacts, adaptations and mitigation
(2014) Sangeda, A. Z.; Malole, J. L.
Livestock are central to the livelihoods of Tanzanians who rely on them for income via sales of milk, meat, skins and draught power. Owning livestock is amongst the ways in which many Tanzanians could diversify their risks, increase assets and improve their resilience to changes in climate. Though local coping strategies can deal with shocks in the short-term, they are hardly able to cope with more frequent and severe climate events. Observably, temperature, rainfall and atmospheric CO2 concentration interact with grazing and land cover change to influence rangeland quality and composition. Increased temperature increases drought stress and tissue lignifications in plants and, consequently, affects their digestibility and decomposition rate. Increased temperature and lower rainfall also increases vegetation flammability resulting in a shift in species composition due to increased fire frequency. Literature indicates that, Tanzania rangelands receiving between 400 and 1000 mm of rain per year (e.g. Kongwa, Monduli, Kiteto, Simanjiro, Ngorongoro, Babati, Hanang, Mbulu and Karatu) have greatest impact on climate change on surface drainage. A 10% drop in rainfall of 1000 mm per year in a rangeland results in a decline in surface drainage of only 17%, while in areas of 500 mm per year will result in a 50% decline. Interventions such as controlled animal stocking rates, sustainable yield and use of good pasture will lessen the negative impacts of climate change on rangelands. Opportunities for reducing greenhouse gas emissions on rangelands include maintaining or increasing carbon sequestration through better soil management and reducing methane production by altering animal management practices on rangelands. There is a need to focus on enabling herd mobility through securing better access to water resources, land use planning, and improve early warning systems and supporting a diversification of livelihoods.

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