Theses and Dissertations Collection

Permanent URI for this collectionhttp://10.10.97.169:4000/handle/123456789/33

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Access to formal credit and its linkace with agricultural technologies adoption: a case of smallholder farmers ln Zanzibar
(Sokoine University of Agriculture, 2009) Mohamed, Khalid Salim
This study was conducted in order to determine the extent of access to formal credit in rural Zanzibar and identify factors that influence smallholder farmers* access to formal credit. It also aimed to assess the linkage between access to credit and the adoption of agricultural technologies. In conducting the study, both primary and secondary data were collected. In the collection of primary data, questionnaires were administered to 750 randomly selected smallholder farmers. The data collected were analyzed descriptively and quantitatively. The results from the study reveal that outreach and access of formal credit in the study areas is low. About 78% of sampled households were found to be credit constrained. It was also revealed that 41% of the credit constrained households were relatively members of the more poor group in the study areas, while only 10% of the non-credit constrained belonged to this group. Furthermore, the study results suggest that the number of times one has received formal credit, keeping livestock, having a bank account, value of productive assets owned and household total income are important factors in influencing smallholder farmers* access to formal credit. The findings also show that the intensity of extension contacts, household size, and the value of productive assets are important factors in influencing agricultural technology adoption among non credit households, while the number of times one has ever received formal credit was found to have more influences in inducing technology adoption among credit constrained households. Based on these findings, it is recommended that smallholder farmers should be availed the opportunities of getting repeat loans in order to improve their chances of accessing credit in the formal credit markets and enhance adoption of agricultural technologies. Farming households can as well be encouraged to diversify their income sources within and away from agricultural activities through promotion of mixed farming and off-farm activities. The need to develop a saving culture in the farming communities is also crucial for ensuring the creation of sustainable and efficient financial system. Furthermore, it is recommended that in order to enhance adoption of agricultural technologies, extension services should be targeted to non-credit constrained households.
Assessment of annual utilization rates of farm tractors in Mbarali district, Tanzania
(Sokoine University of Agriculture, 2015) Lwesha, Emmanuel Mjobege
The study was conducted in Mbarali District of Mbeya Region with the objective of assessing the average annual utilization rates of farm tractors for both on-farm and off- farm activities during the cropping season of 2012/13. The study conducted aimed at addressing the following research questions: who are the owners of farm tractors in the study area, what models were in use and what were the available support services that could enhance sustainable utilization of tractors? Questionnaire and a log–book were the instruments used for data collection for this study. A total of one hundred and eleven (111) farm tractors were involved in this study, of which 90 were power tillers [or 2 wheel tractors (2WT)] and 21 were conventional tractors or 4 wheel tractors (4WT)]. Results obtained show that all conventional tractors were privately owned and 94.6% of the power tillers were privately owned with the remaining 5.4% being owned by farmer’s groups. The age of the tractor owners ranged from 31 to 50 years old and all were able to read and write. Siam Kubota and Amec power tillers were the most popular 2WT in the area. The average annual utilization rates of 4WT was 1093 hours and 627 hours 2WT. Results of annual utilization rates of farm tractors in Mbarali District conclude that both conventional tractors and power tillers are optimally utilized. The study has also revealed that there are many dealers of tractors and spare parts in the District. Most repairs of farm tractors were performed by local mechanics in their respective villages; this therefore ensuring the long term sustainability of utilization tractors in the District.
Assessment of environmental degradation in Nakambala Mazabuka Zambia
(Sokoine University of Agriculture, 1996) Chinjila, Mellon Halubanje
An environmental degradation assessment was carried out in Nakambala Estate, Mazabuka Zambia in October 1994 to June 1995 . The objectives of the study were: impact change, of the natural sugar plantation vegetation between 1970 and 1993 ; (b) and (a) on demographic resource degradation expansion land to assess the to assess the soil physical and chemical status in cultivated and abandoned areas; and (c) to compare current soil physical and chemical status of the study area with the status when the sugar plantation was being established. Sequential aerial photography was used in assessing sugar plantation expansion and its impact on natural vegetation and land resource degradation. The impact of the sugar plantation expansion on demographic changes and energy needs (fuelwood) was also assessed. A field soil survey was carried out to assess soil condition in terms of general fertility and selected land qualities and characteristics matched with the requirements of irrigated sugarcane using the FAO (1983) land suitability framework. Soil carried out by using indices. degradation assessment wasiii The results of the study were; the sugar plantation expanded by 7 035 ha between 1970 and 1991; human population increased by 4 929 (at 4% per annum) and projected to reach 22 127 by the year 2 000. to sugar Natural vegetation was reduced by 25 % due plantation expansion aggravating the fuelwood deficit situation (5 447 m3/year in 1970 and 4 906 m3/year in 1991) . There was no visible evidence of soil erosion although waterlogging was the prevalent form of land degradation in all the mapping units. The soils are generally eutric (base saturation > 50%) with slight acidic to neutral reaction in cultivated fields (in mapping units; 2W, 10, 11 and 12) to slightly alkaline reaction in areas with abandoned fields (soil mapping unit 13). High soil bulk densities occur in soil mapping unit 2W due to compaction by heavy machinery and due to inherent nature of the soils in mapping units 10, 11, 12 and 13 (heavy clays). Oxygen inavailability (due to poor drainage), physical degradation and poor rooting conditions (due to shallow effective soil depth) are the most limiting conditions for sugarcane changes in chemical status growing. Over time, noticeable (sodication) was low in all the mapping units except in unit 10 where sodication development was noticed. Adverse soil physical changes (crusting and surface sealing) occurred in soil mapping units 11, 13. 12 andiv To stem environmental deforestation, degradation in the form of energy utilization from fuelwood should be reduced by electrifying township housing units. The continued use of vetiva grass for drain protection is advised. Alternative land uses in soil mapping units 11, 12 and 13 and complete abandonment of monocropping practices in these soils is strongly recommended.
Assessment of processing methods, sensory attributes, nutritional quality and safety of cassava leaves product (isombe) in Rwanda.
(Sokoine University of Agriculture., 2014) Umuhozariho, Marie Goretti
Cassava (Manihot esculenta Cranz) leaves are cherished as a vegetable in Africa, but contain a toxic compound, cyanide. Studies were conducted to assess utilization, cyanide and nutritional value of cassava leaves after different preparation procedures in Rwanda. After a survey, leaves from bitter, sweet and wild cassava were: (1) pounded and cooked, (2) dried, pounded and cooked, and (3) pounded, dried and cooked. Drying was done to brittleness in a solar dryer after leaves were blanched. Sensory evaluation was done using a five point hedonic scale, where 5= like very much, 4= like moderately, 3= neither like nor dislike, 2= dislike moderately and 1= dislike very much. Cyanogens, vitamin C, P- carotene, crude protein, iron, calcium, phosphorus, potassium, zinc and moisture content (dry weight basis) were determined in: (i) un-dried, (ii) dried, (iii) un-dried and cooked, and (iv) dried and cooked. Tire chemicals of dry stored samples were also monitored after three, six, nine and twelve months. Results showed that cassava leaves from the three species were consumed as food and sun-drying was a single method used by fanners to extend the storage life. Colour, taste, aroma, texture and overall acceptability were principally affected by processing procedures. Fresh and dry leaves were preferred as vegetable except when they were pounded after drying. After boiling for 30 minutes. cyanide level (40 mg HCN/kg) was above FAO/WHO recommendation (10 mg HCN equivalent/kg) in the relish, but was judged as safe for the fact that it is served in small quantities as side food, reducing the HCN by serving to minor levels in comparison to documented acute oral lethal dose of HCN for an adult (30-210 HCN/60 kg bodyweight). Except vitamin C, amounts of P-carotene, iron, calcium, phosphorus, potassium and zinc were considerable, averaging 340, 153,4264, 3531, 8426 and 54 mg/kg, respectively, and protein (34%) was high and valuable for cyanide human body detoxification. Stored, moisture increased significantly by 6.8% and shelf life was estimated at six months in water, air and light proof material. Further studies in Rwanda on cassava cyanide disorders and approximate safe quantities of cassava leaves relish are recommended.
The contribution of forest products to rural livelihoods in Nkasi district, Rukwa, Tanzania
(Sokoine university of agriculture, 2008) Rwamahe, Ansbert Severin
This study was conducted in Nkasi District, Rukwa region, Tanzania, with the overall objective of assessing the contribution of forest resources in improving the livelihoods of rural communities. The focus was on various ways in which local communities in the study area earn income through forest resources. Similarly, the study focused on the types and quantities of the forest products and establishment of the contribution of the products to household income. Primary data were collected from household survey in the study area by using questionnaire, PRA techniques and check list for key informants. Data collected during PRA were analysed with the help of local community. Content and structural- functional analysis techniques were applied for qualitative data and information. The quantitative data were analyzed by using Statistical Package for Social Sciences (SPSS) programme. The secondary data were obtained from the District Natural Resources Office. The results show that indigenous forests provide various types of forest products with substantial contribution to the livelihoods of the household. The forest products comprise about 21% of the total annual household cash income. Likewise, the study quantified the annually utilized forest products per household to be around TAS 186 815. The study also identified endangered plant species orchids which is widely traded and consumed by about 63% of the sampled households. The study shows that most of the forest resource users utilize forest products that require licenses. It was further noted that most of the users do not acquire licenses. Based on the findings of the study, it is recommended that contemporary forest management approaches such as Community Based Forest Management (CBFM) and Joint Forest Management (JFM) should be employed in order to ensure sustainable use of forest resources.
Determination of physical properties of soybean, design and fabrication of improved soybean dehuller
(Sokoine University of Agriculture, 2011) Mushi, Justine Alfred
The objective of this study was to investigate the methods for improving dehulling efficiency and throughput of soybean dehuller, which included studying of some physical properties of soybean at different moisture levels related to dehulling, the use of different pre-treatment methods to loosen the seed coat to facilitate its removal during dehulling, and finally to develop an improved manually operated prototype dehuller which can dehul moist grain without clogging and undertake performance test of this dehuller. Four levels of moisture content ranging from 14 to 20 % dry basis (d.b) were used to evaluate the effect of moisture content on physical properties of soybean grains. In this moisture range, mean grain length, width, thickness, arithmetic mean diameter, geometric mean diameter, surface area, porosity and thousand grains weight increased with increasing moisture content. On the other hand, bulk density, true density and sphericity were found to decrease with increase in moisture content. The prototype dehuller was designed and fabricated with a dehulling surface which can dehul moist grain without clogging. The effect of pre-treatment methods on dehulling was carried out to evaluate the dehulling efficiency and throughput of the prototype dehuller. The pre-treatments investigated included boiling the grain at different durations followed by cooling to room temperature and soaking the grain for different durations followed by a rest period to allow surface moisture to be absorbed. The improved dehuller was used to dehull the pre-treated grain and the effect of pre-treatments on dehulling efficiency was evaluated based on the extent of seed coat removal. Also the effect of different pre-treatments on throughput of the dehuller was evaluated. The dehuller was able to achieve dehulling efficiency of 70.62 % for Uyole Soya-1 and 72.57 % for TGX 1895-33F. Throughput obtained was 50.76 kg/h and 55.50 kg/h for Uyole and TGX 1895-33F, respectively.
Development of a computer-based decision support tool for selection of optimum tractor-plough system for upland farming in Tanzania:
(Sokoine University of Agriculture, 2015) Mwasandube, Amon Cornel
This thesis is the result of a study carried out in Mvomcro District in Morogoro region, Tanzania. The success of this work was made possible by moral and material support of different persons and institutions. First, and foremost, I thank the almighty God for providing me with the courage, strength, guidance, patience and passion throughout my study period, for I understand without him I could not have been able to accomplish this study. I would like to express my sincere appreciation to the Management of the National Institute of Transport (NIT) for enabling and financing my studies in the Department of Agricultural Engineering and Land Planning of Sokoine University of Agriculture. Special thanks are directed to the then top management members: Dr. A. M. Rashid (Principal), Mr. E. Mgonja (Deputy Principal-Academics, Research and Consultancy) and Mr. E Msonge (Deputy Principal- Finance and Administration), for their moral and financial support. Special thanks are directed to my Supervisors Prof. Z. M. Mganilwa, Prof. S. M. Mpanduji and Prof. D. N. Kimaro, for their tireless guidance, wise advice and constructive criticism. Without them my academic dreams and aspirations would have not become a reality. I am indebted to Prof. A. K. P. R. Tarimo for his guidance and moral support during my study. I am extending my sincere thanks to all academic members of staff of the Department of Agricultural Engineering and Land Planning, for their material and moral support, advice and for creating a harmonious environment during my stay at the University. I am also extending my sincere thanks to the Centre for Agriculturalvii Mechanization and Rural Technology (CAMARTEC) for providing test equipment and support staff. 1 am also grateful to the farmers (respondents), extension engineer Mr. Felix Temu and other Mvomero District Council staff including District Agricultural and Livestock Development Officer (DALDO) and extension officers for their support during data collection. I am also extending my sincere thanks to Mr. Issaya M. Mwansasu (National Institute of Transport) and King George Magaga (INFOSYS LTD) for their support during computer programming work. I express my sincere appreciation to my lovely wife Juster Kemilembe Mwasandube and my children Lisa, Merina and Richard for their moral and material support, patience and encouragement which in one way or another made my study successful. Also, I am very grateful to my brothers: Mr. Alley C. Mwakibolwa, P. Mwasandube, Asukenye Mwasandube, my son in-law Daudi Mbugulu, my in-laws T. Kalinjuna and G. A. Kalinjuna for their moral support and encouragement. It is not easy to mention all who contributed in one way or another in making this work done but I say to you all thank you very much. Let the Almighty God grant you all with his glory, peace and blessings.
Development of a computer-based decision support tool for selection of optimum tractor-plough system for upland farming in Tanzania: a case of Mvomero District
(Sokoine University Of Agriculture, 2015) Mwasandube, Amon Cornel
In Tanzania, fanners like others elsewhere, have to make informed choices of optimum and cost effective farm machinery. The level, appropriate choice and subsequent proper use of farm machinery has a direct and significant effect on productivity. Tanzanian farmers use traditional intuitive farm machinery selection methods which, in most cases, results in uneconomical investment. The overall objective of this study was to develop a computer-based decision support system tool for selecting optimum tractor-plough systems in Mvomcro District. This objective was achieved by initial assessment of the status of agricultural mechanization in the study area. Soil and terrain physical properties including soil bulk density, texture, moisture content, cone index, and slope gradients were determined to form a baseline data for selecting suitable farm machinery. Under the determined soil and terrain characteristics, tractor-plough system’s field performance parameters were subsequently determined. Theoretical mathematical models were developed for the simulation of tractor-plough system’s static overturning stability limit on slopes. Using SPSS software, regression models were developed to predict the tractor plough system’s field performance and static overturning stability. Employing mathematical models developed in this study and from the literature, a computer-based Tractor-Plough System Selection Tool (TPSST) was developed. The TPSST used procedures and functions from the database to process data entered by users and displayed the least-cost set of tractor-plough system along with other alternative sets. A sample of TPSST output identified a least-cost set of two tractor-plough systems which are capable of completing a 100 ha farm within allotted time. The set comprised of a 74kW tractor/1.25 m plough system and a 31 kW tractor/0.99 m plough system. The simulation output for the 74 kW tractor-plough systems included: 32 kNO drawbar pull, 26 kN draught force, 16.51/11 fuel consumption and TZS 3 665 720 total annual cost. The simulation output for the 31 kW tractor-plough systems was: 12 kN drawbar pull 4 kN, draught force, 6.9 L/h fuel consumption and TZS 1 665 193 total annual cost. It is expected that the TPSST will assist in performing tasks of different agricultural mechanization stakeholders including designers, manufacturers, researchers, trainers, farm machinery managers, extension staff and consultants.
Development of a computer-based decision support tool for selection of optimum tractor-plough system for upland farming in Tanzania: a case of Mvomero district
(2015) Mwasandube, Amon Cornel
In Tanzania, farmers like others elsewhere, have to make informed choices of optimum and cost effective farm machinery. The level, appropriate choice and subsequent proper use of farm machinery has a direct and significant effect on productivity. Tanzanian farmers use traditional intuitive farm machinery selection methods which, in most cases, results in uneconomical investment. The overall objective of this study was to develop a computer-based decision support system tool for selecting optimum tractor-plough systems in Mvomero District. This objective was achieved by initial assessment of the status of agricultural mechanization in the study area. Soil and terrain physical properties including soil bulk density, texture, moisture content, cone index, and slope gradients were determined to form a baseline data for selecting suitable farm machinery. Under the determined soil and terrain characteristics, tractor-plough system’s field performance parameters were subsequently determined. Theoretical mathematical models were developed for the simulation of tractor-plough system’s static overturning stability limit on slopes. Using SPSS software, regression models were developed to predict the tractor- plough system’s field performance and static overturning stability. Employing mathematical models developed in this study and from the literature, a computer-based Tractor-Plough System Selection Tool (TPSST) was developed. The TPSST used procedures and functions from the database to process data entered by users and displayed the least-cost set of tractor–plough system along with other alternative sets. A sample of TPSST output identified a least-cost set of two tractor-plough systems which are capable of completing a 100 ha farm within allotted time. The set comprised of a 74kW tractor/1.25 m plough system and a 31 kW tractor/0.99 m plough system. The simulation output for the 74 kW tractor-plough systems included: 32 kN0 drawbar pull, 26 kN draught force, 16.5l/h fuel consumption and TZS 3 665 720 total annual cost. Theiii simulation output for the 31 kW tractor-plough systems was: 12 kN drawbar pull 4 kN, draught force, 6.9 L/h fuel consumption and TZS 1 665 193 total annual cost. It is expected that the TPSST will assist in performing tasks of different agricultural mechanization stakeholders including designers, manufacturers, researchers, trainers, farm machinery managers, extension staff and consultants.
Development of a diffusion model for agro-technologies innovation for research and development organisations in Tanzania
(Sokoine University of Agriculture, 2015) Sanga, Fredrick Michael
Research and development (R&D) organisations in Tanzania use old systematic design models that focus on the mere agro-technologies prototypes development, instead of innovation of agro-technology for diffusion. A serious gap exists in the incorporation of the agro-technologies diffusion factors in design models in R&D organisations in Tanzania. The twin valley of technology death describes the technology development failures based on business vision disregard. Technology prototypes or services are developed, though are not linked to business setup, and that they don‟t get ripe to earn money through commercial sales. This study identified that there is no customised model for agro-technology diffusion in research and development organisations in Tanzania. Structured questionnaires, interview with R&D organisation staffs and stakeholders and observation of activities in these R&D organisations were used to collect data from sources identified. Literatures on engineering design, technology development for diffusion and various models for innovation were studied. The factors that were linked with agro-technology were identified and their related variables and hence the model was developed, that proved to be useful in guiding technology developers in ensuring the good final diffusion of technologies to above 95% significant level. Regression analysis and system dynamic model development and analysis were used to organise identified factors into agro-technology innovation diffusion model. The model was calibrated and validated using data collected from various R&D organisations in Tanzania between the year 2011and 2013. Factors that were included in the model are: relevance of needs identification, need identification, interpretation of variable into design specification, agro-technology validation process, agro-technology information generation and proper agro-technology packaging and agro-technology development stages importance. These factors were found to affect agro-technology diffusion at a rate between 10 and 65%. It was noted that the development of technology for diffusion is more than the prototype development. By using the model with its useriii interface provides guidance to agro-technology developers that the control of innovation diffusion is above 95% confidence interval. However further work to improve the model especially on time adjustment and other socioeconomic factors like human resource requirement, fixed capital and R&D organisation rationalisation in Tanzania that has to be done
Development of a model for integrated anaerobic digestion, solar and wind energy system for rural semi-arid areas
(Sokoine University of Agriculture, 2021) Yustas, Yusto Mugisha
The availability of sufficient energy and its efficient use is a primary factor in improving and sustaining the economic and technological development of any community. However, there are several challenges related to access to sustainable energy in the countries of Sub- Saharan Africa (SSA). Inadequate access and connectivity to affordable, sufficient, and clean energy for off-grid rural communities remain a major limiting factor for development. For instance, only 15% of rural communities in SSA have access to electrical energy, which indicates the severity of the problem. SSA countries have initiated efforts to address the challenge. For instance, Tanzania has progressed by increasing access to energy for the rural population from 49.3% to 69.8% from 2016/2017 to 2019/2020. However, the challenge is still far from being addressed; therefore, more efforts are required to address them. Efficient exploitation of renewable energy resources and sources (RERS), which are readily available in most rural communities of SSA, would be ideal for reducing the challenge of limited energy access and connectivity. However, the RERS have not been adequately utilised in rural communities. The major challenge for insufficient use of RERS in rural communities is the high cost and inefficiency of available RESRS technologies. The technology must be affordable and efficient while it generates clean energy from the use of RERS. Different countries have taken several initiatives to curb the challenge of insufficient use of RERS in SSA. For instance, in Tanzania, a continuous fed fixed dome biogas technology of 4-6 m 3 digester capacity was introduced in rural semi-arid areas of Dodoma under the subsidy scheme. However, the technology had limited adoption because the system was too expensive for low-income communities; also, the system had technical and operational constraints. One of the constraints included difficulties in troubleshooting faults in the digester system since the digesters were installed underground to reduce their temperature variation. Another constraint was scarce water in the area since a large quantity of water was required to run such systems. Therefore, further research for alternative affordable and efficient renewable energy systems as part of the efforts to reduce energy scarcity was necessary. Consequently, this study sought to develop a novel integrated anaerobic digestion, solar, and wind energy system, simply the i-SWEAD system. The system generates energy for households in rural semi-arid areas. The system’s affordability and efficiency were essential targets to be met. The study was conducted in the Idifu village of Dodoma, Tanzania, as a representative of the semi-arid areas of SSA. Four specific objectives were set and executed to achieve the study aim. These specific objectives were to (i) characterise the available renewable energy-related resources and variation in ambient temperature, (ii) design and test the functionality of the i-SWEAD system, (iii) model the biogas production of the i-SWEAD system, and (iv) conduct a techno-economic appraisal of the i-SWEAD system. Characterisation of the available renewable energy-related resources and the ambient temperature was done in the following manner. Firstly, the cow dung samples were collected from the study site and analysed in the laboratory to determine their chemical and compositional properties using proximate and ultimate biomass analysis methods. Secondly, solar irradiance, wind speed, wind direction, and ambient temperature were measured using a weather station installed at the study site. It was found that the available cow dung contained essential qualities (volatile matter of 744.3± 53.2 g/kg of dry matter and a Carbon Nitrogen ratio of 19.3) for biogas generation. Also, the amount of solar energy (solar insolation of above 4.5 kWh/m 2 /day for seven months in a year) and wind energy (average annual wind speed of 4.69 m/s at 4 m hub height with predominant wind direction from North East) were adequate. However, the ambient temperature variation was ±4.04 o C within a day, which poses a challenge for adopting a biogas generating unit installed on or above the ground without heat insulation features. Therefore, the design of the i-SWEAD system must consider the limitation in temperature variations. As a result, the i-SWEAD system was designed to meet the functional requirement of producing biogas and electricity. An anaerobic digestion system was designed and resulted in an Adapted Batch-Fed Anaerobic Digestion (ABFAD) system to curb limitation in biogas clogging; then, the ABFAD system was integrated as a sub-system of the i- SWEAD system. The ABFAD system was tested separately to check if it adequately addressed the challenges of biogas clogging; also to establish its functional curves useful for the system operating status indication. The results revealed that the system had addressed those challenges and some other conventional biogas generation systems’ challenges. The data collected for pressure, pH, and dissolved oxygen during the testing of the ABFAD system were useful in developing their functional characteristic curves. Similarly, the i-SWEAD system was tested for its functionality. The results showed that the system had an average biogas yield of 0.077 m 3 /kg of fresh cow dung (0.343 m 3 /kg of cow dung dry matter) and methane content of 48.57±2.15%. Also, it had a biogas production rate of 0.54 m 3 /m 3 of digester in a day. The i-SWEAD system kept its digester temperature variation within 1.28 o C/day, which is tolerable to biogas microbes. Despite the adequate performance of the i-SWEAD system, further analysis would make it robust for adoption and upscaling. In that sense, modelling biogas production of the i-SWEAD system becomes the core of its success in reaching a broad community. An Artificial Neural Network (ANN) modelling technique was used to model the biogas production of the i-SWEAD system. The method was chosen because of its robustness, and since the anaerobic digestion processes are non-linear, the ANN modelling technique fits well. The ANN technique was used to generate six predictive models for the i- SWEAD system. The models were evaluated to choose the best model, which can adequately predict biogas production in the i-SWEAD system. The data used for training the model and testing its performance were solar irradiance, wind speed, ambient temperature, digester temperature, hydraulic retention time, and biogas volume. Data were separated into two sets to train the model (75% of the data) and test the model (25% of the data) using a random method. The model predictive power was evaluated using the Absolute Model Predictive Accuracy (AMPA). It was found that the chosen model among the six predictive models generated, i.e., Model4, was robust with the AMPA value of 99% for the i-SWEAD system. Therefore, the model gave the required predictive accuracy in this study, implying that it can be adopted in decision making. Thus, the ANN technique proved to be useful in building an appropriate model for the i-SWEAD system’s biogas generation prediction. Both the technique and the model are recommended for utilization. Furthermore, it was necessary to conduct the techno-economic appraisal of the i-SWEAD system to check if the system was efficient and affordable for the low-income communities in semi-arid areas. Comparison was made to the ABFAD-solar system to check if the i-SWEAD system was more efficient and affordable. The total energy generated per year was quantified for both systems. It was found that the i-SWEAD system produced higher energy (267 kWh/year) than the ABFAD-solar system (239 kWh/ year). The i-SWEAD and ABFAD-solar systems had the same digester size (0.24 m 3 ), same solar PV module rating (20 Wp), while the i-SWEAD system had an additional wind turbine with the power rating of 54 Wp. The i-SWEAD system's capital investment was TZS 1 136 000.00 or € 2017 494.00, while the capital investment of the ABFAD-solar system was TZS 971 240.00 or € 2017 422.00 meaning that the latter is cheaper. However, the Internal Rate of Return (IRR) analysis shows that the i-SWEAD system had an IRR value of 16.6%, while that of the ABFAD-solar system was 10.4%. Therefore, the i- SWEAD system was found to be more economical than the ABFAD-solar systems. The costs of both i-SWEAD and ABFAD-solar systems are within the affordable range based on the National Bureau of Statistics (NBS) of Tanzania. However, given the advantage of the total energy production and value of IRR, the-i-SWEAD system can be considered a better option. The system is technically and economically justifiable as an efficiently feasible and affordably viable project useful for contributing to energy accessibility, based on its detailed techno-economic assessment results. Therefore, the system is novel, adequate, and worthy of being promoted for adoption and upscaling after training users on how to operate and test it in low-income communities of SSA’s rural semi-arid areas.
Development of power tiller operated rice combine harvester for smallholder farmers in Tanzania
(Sokoine University of Agriculture, 2013) Mwinama, Godfrey
This study was conducted to develop a Power Tiller Operated Rice Combine Harvester (PORCH) for small holder farmers in Tanzania. PORCH can be attached to a power tiller during harvesting operation and detached to give the power tiller a room for other operations. The study aimed at designing, construction and testing performance of PORCH prototype.Design specifications and drawings were developed and prototype was constructed.The performance of PORCH prototype was tested in Lower Moshi and compared to manual harvesting. Comparisons made included manpower required (man-h/acre), harvesting capacity (acre/h), grain loss (%), presence of material other than grain (MOG %) in the harvested grain, and harvesting cost. It was foundthat in PORCH harvesting average values of man-h, harvesting capacity, cost, grain loss and MOG were 4.76 h/acre, 0.42 acre/h, TSh.30151/acre, 28.86% and 3.19% respectively. While the average values of man-h, harvesting capacity, cost, grain loss and MOG for manual harvesting were 255.9 h/acre, 0.0039 acre/h, TSh. 181250/acre, 14.84% and 8.3% respectively. Hence PORCH harvesting was better for all performance measures made except grain loss reduction. More grain loss in PORCH harvesting was due to leakagesin some of PORCH functional elements. Grain loss can be reduced by avoiding leakages in PORCH functional elements. It was recommended in future that modifications should be done so as to alleviateshortcomings in PORCH functional elements.
Digital processing of landsat thematic mapper satellite data for land cover classification using statistical methods for accuracy assessment: a case study of Ngerengere watershed
(Sokoine University of Agriculture, 1998) Mahuha, Fares Enock
This study involved primarily digital image processing and interpretation land for classification . cover Part of Ngerengere watershed covering about 300 km2 was taken as a case study Land cover which relates to the type of feature present on the surface of the Earth of the study area was elaborated. The procedures involved were reconnaissance survey to acquire 'a priori' knowledge about the u n s u pe r v i s e d area, classi f icat ion, field work classification, for rectification and restoration, ground supervised truthing, image ultimately producing and a land cover map of Ngerengere watershed. ERDAS 7.5 was the remote sensing (RS) software applied. The elaborated accuracy, land using cover map statistical was assessed packages. foric.s Overall classification accuracy (OCA) was about 70% which was below the recommended minimum level of interpretation accuracy value of 85%. It was however, revealed that the low OCA was substantially attributed by low producer's accuracy for the class of built-up areas which was only 22%. Although the produced land cover map had relatively low OCA, it had agood correlation with the present land use and vegetation. Further statistical analysis, by use of KHAT (K) statistics gave a value of 0.65 which is above 0.5 and approaches 1.0, hence acceptance of the land cover map produced from thatiii classification as primary data for land use planning. It percentage of also indicated extent the which to correct values of an error matrix used are due to true agreement and not by chance agreement. Chi-square (X2)distribution to test the goodness of fit of the land cover map elaborated, concluded absence of significant difference between the obtained and recommended OCA at significance level reject of and hence absence of enough evidence to 0.01, the classification for various applications like proposal for land use planning. In order to come up with a sustainable land use planning of the area, category other data are required. needed its own ancillary Every land cover data which are site specific to come up with. a proposal or alternatives for land use planning of an area. For instance, agricultural lands and rangelands classes needed much more ancillary data due to their spectral similarity and inseparability characteristics revealed during this study. Finally it is recommended for continuation of the study so as to come up with a sustainable land use planning of an area because thereis a problem already and timely intervention is imperative operation for the betterment of future generation.
The effect of bushfires on abundance and diversity of mammals in miombo woodlands under different forest tenure, Kilombero district Tanzania
(Sokoine University of Agriculture, 2013) Matimbwi, Lukelo
Miombo woodlands are the largest savanna in the world and dominate southern Africa. They support the livelihoods of over 100 million people and are strongly influenced by anthropogenic fires. This study was conducted with the overall objective of determining the effect of bushfires on mammals in miombo woodlands under different forest tenure systems. Household questionnaires, checklist of probe questions for key informants, participant observation, PRA techniques and field inventory were employed in data collection. Data collected during PRA were analyzed with the help of the local communities. Content and structural-functional analysis techniques were applied to qualitative data and information. Statistical Package for Social Sciences (SPSSs) software was used to analyze quantitative data. Microsoft excel software tools were used to analyze mammals stocking data collected through inventory. Analysis of Variance (ANOVA) was used to test whether there were significant differences between the mean numbers of mammals obtained from different forest tenure systems. Shannon - Wiener Index (H‟) was used to determine species diversity of mammal species from different forest tenure systems. The results indicated that the main causes of bushfires in miombo woodlands was due to farm preparation 44.5%, charcoal making 21.1% and hunting wild animals 18.9%. Illegal timber harvesting and honey harvesting were considered as minor causes. In most cases the total numbers of mammals in a given area were higher in Central Governmental Forest Reserve followed by Local Government Forest Reserve and the least in Village Forest Reserve. However for the diversity indices, the mildly burned blocks in the Central Governmental Forest Reserve were 3.2 while in the Village Forest Reserve it was 2.0 and in the Local Government Forest Reserve it was 1.6. For moderately burned blocks the diversity index value for the Central Governmental Forest Reserve and Village Forest Reserve were similar which were 2.0 while it was 1.6 in the Local Government Forest Reserve. For the severely burned blocks the diversity values were 1.5 for the Central Governmental Forest Reserve, 1.4 in the Village Forest Reserve and 1.2 in the Local Government Forest Reserve. Mammals with low fire escape rate such as rock hyrax were more severely affected by bushfires. It is, therefore being recommended that the current Local Government Authority management regimes should be strengthen to ensure increased local community participation with more effective law enforcement measures so as to rescue the forests from degradation. Communities should, similarly be empowered with credit facilities and support on income generating activities so as to reduce dependence on miombo woodlands.
The effect of insecticidal plant materials on the quality of stored beans
(Sokoine university of agriculture, 2021) Kabyazi, Evance Kamanya
The research was conducted at the Department of Engineering Sciences and Technology of Sokoine University of Agriculture (SUA) to study the effect of insecticidal plant materials (neem and eucalyptus leave powder) on mortality of bruchid bettles and quality of stored beans for three months storage period. The objectives of the study were; To determine the effect of different concentrations of insecticidal plant materials on insect pests mortality in stored beans, to determine the effect of different concentrations of insecticidal plant materials on organoleptic qualities of stored beans and to determine the effect of different concentrations of insecticidal plant materials on seed viability of stored beans at different storage duration. Three rates (10, 20 and 30 g/kg) of each insecticidal plant leave powder, a synthetic insecticide (Shumba supermax dust at 0.5g/kg) and an untreated grain were used as treatments. The experiment was arranged in completely randomised design in four replications. Data collected include; Insect mortality, odour, taste and seed viability index of stored bean grains. Data collected were subjected to analysis of variance (ANOVA) using General Linear Model in SPSS computer software packages (version 16) and mean comparisons were conducted using Turkey’s (HSD) test at 5% level of significance. Results showed a significant difference in percent mortality of adult bruchids due to the effect of insecticidal plant powders. The increase of adult bruchids mortality was directly proportional with the plant powder concentration. The application of insectical plant materials had influence on organoleptic quality of stored beans. However, the insecticidal plant powder had no significant effect on seed viability when compared to the controls. It can therefore concluded that, the insecticidal plant material can be used to protect grains against bruchid damage and on stored seeds for planting. For home consumption, the treated grain should be washed thoroughly with water to remove remained residue before use.
Effect of irrigation regimes on yield and quality of grapes (Vitis vinifera L. cv. ‘Makutupora red’) in Dodoma, Tanzania
(Sokoine University of Agriculture, 2018) Njovu, A. M.
A growing viticulture industry in Dodoma, Tanzania has sparked a need to establish best management in irrigation practices for the improvement of quality of vine grapes and wine. Drip irrigation is important in vines cultivation in tropical semi-arid areas as it improves water productivity more than other irrigation systems. Fully irrigated grapes have shown to have higher yield and lower grape quality when compared to rain fed grapes which are coincidently under limited water availability. The use of deficit drip irrigation in Marlborough New Zealand showed substantial improvement in grape quality. However, the information of using deficit irrigation in vineyards in Dodoma is inadequate. Farmers require information on deficit levels that will give optimum grape yield and quality without detrimental effect to the vines. A study was carried out in Dodoma Region in two seasons in 2014 and 2015 for the determination of water requirement for Vitis vinifera L. cv. ‘Makutupora red’ (crop evapontranspiration) by compensation heat pulse method. Sap flow sensors were used for measuring transpiration and soil moisture probes were used for estimating surface evaporation. The vines mean daily transpiration was 3.91 mm per day. The mean daily evaporation was 0.38mm per day. Total seasonal evapotranspiration was 581mm. Grapevine mean daily crop and basal coefficients for grapevine cv. ‘Makutupora red’ were0.31 (Kc) and 0.28 (Kb), respectively. The vine water consumption was high at fruit set to veraison when the canopy was fully developed. After the determination of vine crop water requirement, the vines were subjected to deficit irrigation. Water was applied to the vines using different irrigation regimes at four irrigation levels, which were 100%, 63.5%, 56.3% and 48.9% of crop evapotranspiration (ETc), interacting with three irrigation methods, which were conventional drip irrigation (CDI), partial root zone drying (PRD) and root zone deficit rationing (RDR). The grape yield and quality were optimum in conventional drip deficit irrigation method (CDI) at 63.5% and 56.3% of ETc. Moderate deficit irrigation proved to be the ideal irrigation practice for improving grape quality with a little decrease in yield. The improvement of water productivity by application of deficit irrigation and the relationship between yield and quality components and the amount of water used by cv. ‘Makutupora red’ were investigated. Water productivity was higher in irrigation regimes (treatments) CDI at 63.5% and 56.3% of ETc and in RDR at 63.5% which produced optimum yields with good grape quality. In all full irrigated regimes (at 100% of ETc) vines gave higher grape yields and low grape quality than regimes under deficit irrigation. Pruned mass, leaf area index, berry diameter, berry weight and cluster weight (most of yield components) decreased with water deficits. Total soluble solids, alcohol, phenols and anthocyanins (most of quality components) were higher in vines under deficit irrigation than in full irrigated vines. Malic acid and tartaric acid did not show significant difference between full irrigated grapes and grapes subjected to deficit irrigation. The finding in this study showed that the use of conventional drip irrigation method at moderate water deficits is the best option because it produced optimum grape yield and grapes of high quality. The relationship between water use, grape yield and quality showed that moderate deficit irrigation improved grape quality and minimized the use of water by vines.
Effectiveness of selected vegetation cover types as sediment filters: a case study of Lake Victoria shore line, Magu District, Tanzania
(Sokoine University of Agriculture, 2009) Masanja, Emmanuel Daniel
A study was conducted in Ihale Village, Magu District, Tanzania aimed to assess the effectiveness of selected vegetation cover types as Vegetative Buffer Strip Filters and their corresponding vegetation strip widths in filtering sediment delivery that are likely to enter the surface waters of the Lake Victoria from agricultural lands. Sediment laden runoff plots measuring 2 m by 20, 15, 12.5 and 10 m were established to determine the effectiveness of the selected filters and strip filter widths set at 10, 5 and 2.5 m against a standard width of 10 m which was planted with maize (Zea mays). The filters evaluated include elephant grass (Pennisetum sp) and Lemon grass (Cymbopogon citratus). Variables measured include: daily sediment for the rainy days, daily rainfall, infiltration rates, plant vigour of the filters (plant height) and percent vegetation cover. Data was analysed statistically using Excel, SAS and SPSS statistical packages. The results demonstrate that mass of sediment delivery through the tested filters decreases exponentially with increasing filter widths for all tested vegetation types with correlation coefficient (R 2 ) ranging from = 0.6 to 0.8. The trapping efficiency of the tested filters increases logarithmically with increasing filter widths. Sediment trapping efficiency increased from 54% at 2.5 m to 78% at 10 m vegetative filter widths for all tested vegetation types. A significant correlation exists between sediment delivery through elephant grass and lemon grass with filter strip width, percent vegetation cover and plant growth characteristics. About 30 to 40% of the observed variation in the prediction of sediment delivery through selected vegetation types could be explained by the percent vegetation cover alone. The study demonstrates that the tested Vegetative Buffer Strip Filters have the potential to purify water from sediment that has been transported into the riparian zone from the agricultural lands. Further research is recommended.
Evaluation of drip irrigation system on coffee (coffea arabica): a case study of kilimanjaro plantation in moshi district kilimanjaro region tanzania
(Sokoine university of agriculture, 2010) Clemens, Robert Edward
This study was conducted at one of the estates in Kilimanjaro Plantation to assess the performance of the drip irrigation system on coffee yield. Climatic, plant and soil factors were used for the calculation of monthly crop water and irrigation requirements and results compared with actual performance of the irrigation system. Further evaluation of the system performance was carried out using catch cans. The experiment was carried out on a 3-year-old coffee cultivar N39 at 3m spacing between lines of plants and 1.5 m between plants. The experiment was laid out in a randomized complete block design with five treatments replicated four times. The treatments included five irrigation application levels: T1, T2, T3, T4 and T5 corresponding to flow rates of 0, 0.6, 1.2, 1.8 and 2.4 lph/emitter respectively. The results from calculations showed that the daily irrigation requirement is 18 litres per tree, or applying 90 litres at an irrigation interval of 5 days at peak demand. The EU in the selected block was found to be 94%, which is within the acceptable standards. The wetted area ranged from 0.12 to 0.21 m 2 . The relative water supply ranged from 0.45 to 0.98 indicating that the crop demand was not met by both rainfall and irrigation. Coffee yield and water productivity was also investigated. The best treatment towards the yield of coffee was T5 which produced mean yield of 2945 kg/ha while treatment T1 produced the least yield of 2045 kg/ha. The best WP was 1.56 kg/m 3 found in T1 and lowest was 0.95 kg.m 3 in T5. There were significant differences in yield and irrigation water productivity between treatments. T1 and T2 were not significantly different. It is recommended that further research covering other parts of the plantation should be conducted to confirm the results from this study.
Evaluation of normalized difference vegetation index of common vegetation habitats for monitoring rodent population and outbreaks in Isimani, Tanzania
(Sokoine University of Agriculture, 2017) Chidodo, D. J.
Rodent pest outbreaks are major concern for agriculture in Africa and Tanzania in particular, especially in drier areas such as arid and semi-arid agro ecosystems. This is due to the fact that, if the problem cannot be treated with seriousness it deserves, 80% of the potential harvest may be lost. Crop losses occur at all stages (i.e. field to market). However, higher losses occur at the field/harvest and storage where rodents play a major role. Severe rodent outbreaks have been reported in many areas in Tanzania e.g. the recent outbreak reported by farmers in Isimani division, Iringa, Tanzania. Based on literature, it is estimated that rodents cause 15% of the total crop pre and post-harvest losses. The problem is compounded by unpredictable rodent pest outbreaks, late control actions, and lack of adequate interventions guided by ecologically based rodent management strategies. Recently, efforts have been taken to develop an ecologically based rodent management strategy which requires knowledge about the pest species' ecology in order to reduce the damage experienced by farmers. However, this is constrained by the limited knowledge about rodent populations on individual farms to allow smarter approaches for control of rodent outbreaks. Structural characterization and mapping of vegetation habitats could contribute knowledge about rodent populations on individual farms. Such studies may include describing and measuring vegetation and habitat structural component using geo spatial and statistical approaches (i.e. life form and cover types, terrain, soil and management practices) across various landscapes in different seasons and their influence to small mammal abundance. Recently, it has been reported that remote sensing derived vegetation indices could be used to explain rodent pest abundance at fine scale. Vegetation indices such as the Normalized Difference Vegetation Index (NDVI) have been reported to correlate well with vegetation productivity (i.e. biomass), forage quality and quantity (i.e. food) at moderate resolutions over a range of spatial-temporal scales. Such indices have been reported to be vital tools for studying vegetation habitat characteristics (i.e. vegetation cover) and their association with rodents in space and time. Therefore, the current study was envisaged to evaluate the potential of NDVI of common vegetation habitats derived from satellite remote sensing data for monitoring rodent population dynamics and outbreaks in order to contribute knowledge for refining ecologically based rodent management strategies. More specifically, the study was carried out to i) characterise and spatially map the vegetation habitats associated with small mammal abundance in smallholder farming agro-ecosystem; ii) determine the Normalised Difference Vegetation Index (NDVI) of common vegetation habitats and rainfall patterns in the study area; and iii) establish a relationship between NDVI of the common vegetation habitats and small mammals distribution and abundance in space and time. The study was conducted between September 2015 and June 2016 in Isimani Division, Iringa Tanzania. A combination of field survey and Geospatial approach including the use of Multi temporal Landsat 8 (Operational Land Imager (OLI)) images were applied to identify and map the vegetation habitats and estimation of NDVI. The NDVI of common vegetation habitats and rainfall patterns were also explored. Small mammals were trapped in the mapped vegetation habitat units, and counted for abundances. In total, nine main types of vegetation habitats were investigated. A total of 597 small mammals, potentially related to major rodent pests were trapped. Different levels of scales and resolutions were considered. Linear regression analysis was employed to establish the important habitat characteristics (predictor variables) for relating rodent abundance with rainfall and NDVI. Linear regression analysis was also used to clarify the relationships between ground measured rodents and predicted rodent abundance from rainfall and NDVI across seasons, and calculation of the Pearson correlation coefficient (r) at P ≤ 0.05. Results show that, vegetation habitats identified based on land use/cover types were largely dominated by agriculture covering about 60% of the plateau landscape with intensive maize cultivation and frequent reported rodent outbreaks. The findings show further that, the plateau habitats support a large number of small mammals (80%) than the rest of the habitats in the other landscapes. A strong correlation (r=0.96) was obtained between ground measured point rainfall data and the real time Tropical Rainfall Measuring Mission (TRMM) Precipitation Analysis rainfall data across the identified vegetation habitats. Spatial variability of mean NDVI values with seasonal pattern across the studied vegetation habitat units were obtained whereby, higher values (0.2 to 0.6) were observed in wet season and lower values (0.0 to 0.2) in the dry season. The findings have demonstrated a good positive correlation between rainfall and NDVI along the elevation gradient of the studied landscape units with escarpment having higher correlation (r=0.688) than the plateau (r=0.653) and the valley floor (r =0.652). This relationship suggests that rainfall patterns could be easily predicted from a link between NDVI and elevation as predictor variables. Results also show that, NDVI and rainfall derived from satellite data (Landsat 8 (OLI) images) have positive influence on the rodent abundance over the studied seasons. It was observed that 98% of the predicted rodent abundance was explained by NDVI while rainfall explained only 85%. NDVI predicted rodent abundance showed a strong positive correlation (r=0.99) with the field measured rodent abundance. The obtained NDVI values provide a robust measure of the presence and abundance of vegetation across the studied vegetation habitats which could be very useful in monitoring rainfall dynamics and as a proxy for predicting rodent pest abundance. The findings have revealed that rainfall, NDVI, and elevation were important predictor variables that could be considered for predicting small mammals or rodent pest abundance in the study area. These results support the hypotheses that NDVI of common vegetation habitats has the potential for monitoring rodent population dynamics under smallholder farming agro-ecosystems. Hence, NDVI could be used to model rodent outbreaks within a reasonable short time compared to the sparse and not readily available rainfall data. Further research is required to explore the existing relationship between vegetation habitats with their associated microclimate and rodent pests in the hotspot areas. In addition, relationship between NDVI and rodent pest species composition and community structure in different habitats and seasonal rainfall patterns should be explored.
Evaluation of rainfall interception models in a maize field
(Sokoine University of Agriculture, 1996) Simwanza, Hopeson Isaac
Rainfall interception is a component of effective rainfall and is an important component in agriculture because of the latter's use in irrigation and drainage projects. A rainfall interception study was carried out at Kabanana farm plot no. 2952 M, a peri urban area in Lusaka, Zambia. The objectives of the study were (a) to measure rainfall interception by maize crop growing in a freely drained soil and (b) to evaluate and validate the models developed to represent rainfall interception loss. Standard raingauges placed adjacent to the study area and beneath the canopy of the maize plant were used to measure rainfall amounts. Funnel like collars were used to measure stemflow. A planimeter was used to measure leaf area required for the calculation of leaf area index and the data from the nearby University of Zambia meteorological station was used to estimate crop evapotranspiration. The results of the study showed that the interception process by a maize plant brought about an interception loss of 10%. Interception loss without stemflow was 27.4% implying that 17.4% of the incident rainfall reached the ground by flowing down the stalk of the maize plant as stemflow. Of the four models tested the models developed by Merriam (1960) , Leonard (1965) and De Jong and Cameron (1979) did not represent the process of interception by a maize plant. The linear regression model adopted by Gash (1979) which is insensitive to canopy structure was 93% significant for a two sided t-test at 95% confidence interval. It is highly recommended that the models should be calibrated before being adopted and a model should be developed that includes among the usual measurable parameters, leaf area configuration and branching patterns.

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