Theses and Dissertations Collection

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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.
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.
Transfer and utilisation of selected agricultural production innovations in Tanzania: a case of Kilosa district
(Sokoine University of Agriculture, 2010) Mwanga, Lilian Jesse
Farmers can potentially increase their productivity through adoption of agricultural production innovations, practices, and new input packages, if appropriate extension services are put in place. However, many conventional extension approaches in Tanzania have received criticism for being limited to demonstration of technologies. limited use of farmer’s knowledge, and using the already packaged information. Thus, this study) was conducted to assess the extent of availability, transfer and utilisation of selected cotton and maize agricultural production innovations in Kilosa district, Morogoro region. Specific objectives of the study were to: identify agricultural production innovations available to the extension service; determine the extent to which agricultural production innovations are transferred and utilised; and identify factors contributing to success or failure in transfer and utilisation of agricultural production innovations. Data were collected from 144 respondents including 120 farmers. 4 extension workers and 20 key informants using questionnaires, researcher’s diary and checklist. Data were processed and analysed using SPSS computer programme and “content" analysis technique. The findings showed that agricultural production innovations are generally available although in forms that vary in terms of degree to which they can be helpful to the field extension worker and the farmer. The extent of transfer of agricultural production innovations tends to vary from crop to crop, depending on emphasis given by the government in favour of a particular crop. It was concluded that some of the constraints to transfer such innovations arc of extension nature while others are clearly beyond the responsibilities of the extension worker. The study recommended that efforts be made to refine agricultural production innovations; provision of necessary incentives lo extension workers (such as transport and regular in-service training): and undertake case studies on interaction between field extension workers and farmers.
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.
Valorisation of immature cereal grains to improve food security in Sub-Saharan Africa:a case study on pepeta in Tanzania
(Wageningen University, 2022-04-05) Miraji, Kulwa Furahisha
Cereals contributes a substantial proportion of the food supply for humans and animals globally, including in the SSA where they form a major source of dietary energy and protein intakes as staple foods. Beside their importance to food supplies and health, they contribute to improved income among the most food‐insecure population groups in SSA countries. However, most of cereals are consumed as refined products (dehusked or polished) to improve their sensory properties. This renders the processed cereal-based products of poor nutritional quality as the refining process also removes important nutrients. On the other hand, there is increasing trend of consumers wanting more cereal-based healthy foods containing specific health-promoting properties. In this sense, immature cereal-based products such as pepeta (a locally processed immature rice flakes from Tanzania), appear to be among the many alternatives to pursue the goal of better cereal-based nutrition due to their nutritional potential benefits. It has been found that immature cereals and their products contain higher amount of numerous nutrients beneficial to health, including dietary fiber, vitamins, minerals and phytochemicals, compared to their mature counterparts. However, the information about the effect of processing on the nutritional and sensory properties and the bioavailability of nutrients in immature cereal grains and their products such as pepeta, is limited. Therefore, it is important to assess the traditional knowledge of pepeta product and its quality to improve the processing conditions and products’ nutritional, sensory, and digestibility properties. In Chapter 2, factors that can affect the pepeta value chain, as well as pepeta processing elements that interact with food and livelihood security such as availability of immature rice, pepeta processing techniques, storage practices, product characteristics, preferred product attributes, as well as pepeta trade supply chain and problems, were surveyed among the key players of pepeta processing chain: rice farmers – producer of sole raw materials, i.e., immature paddy grains used in pepeta processing; processors – local indigenous knowledge practitioner with vast knowledge on pepeta processing; and consumers - pepeta end-users with or without pepeta processing knowledge. Results indicated the potential role of pepeta to reduce food insecurity, especially among the rural poor as hunger breaker, i.e., a source of an early food when the crops are yet to reach maturity, and households’ food supply is inadequate. Moreover, as a traditional processing knowledge, the pepeta processing parameters and conditions were not standardised, affecting consistently production of good quality pepeta products. Since pepeta processing knowledge involve roasting of immature rice grains, it was of paramount importance to investigate changes in nutrients content and digestibility during maturation of rice grains, as well as upon processing into pepeta products (Chapter 3). Generally, immature rice grains destined for pepeta production had a higher amount of most nutrients such as lipids, protein, ash, soluble and insoluble dietary fibre, as well as B group vitamins such as thiamine, nicotinic acid, and nicotinamide compared to mature counterparts. Though pepeta processing improved the nutritional properties of rice, a very high and fast starch digestibility comparable to that of cooked milled and polished rice, diminish the health benefits of the pepeta product. Therefore, these findings necessitate further improvement of pepeta processing techniques and the nutritional quality and functional properties of traditionally processed immature rice- based products such as pepeta. From this point of view, the following chapters of this thesis were designed to optimise the processing conditions that improve the specific nutritional, functional and sensory properties of traditionally processed pepeta products (i.e., maturity and roasting conditions (soaking and temperatures)). In Chapter 4, the laboratory simulation of pepeta processing was employed to investigate the impact of dry-heat processing at different conditions on the nutritional composition and in-vitro starch and protein digestibility of immature rice-based products. The results indicate that the nutritional profile of immature rice products can be modulated by processing conditions, dry heating improves vitamin and mineral content when compared to raw and cooked immature rice. Soaking before roasting greatly increased the iron content compared to zinc, thiamine, riboflavin and nicotinamide, indicates the possibility for processed immature cereal products that were soaked before roasted to combat iron deficiency. Moreover, dry heating reduces both protein and starch digestibility when compared to cooked immature rice, where disulphide bonds play a vital role in heat-induced protein interactions in immature rice. The effect of maturity and different processing practices on rice and immature rice-based products’ visual quality and volatile profile was assessed under laboratory simulation, as well (Chapter 5). It was found that both the maturity and roasting influences the colour and volatile profiles of rice grains, whereas soaking before roasting limits non-enzymatic browning process such as Maillard and caramelisation reaction, and diffusion of bran pigments into rice starchy endosperm. The results are vital towards understanding the sensory properties of immature cereal-based products such as pepeta which are critical for the product’s acceptability by consumers. All the findings of this thesis were integrated and discussed in Chapter 6. The discussion focused on the role of immature cereals and their products towards improving the nutritional and sensory properties of cereal-based food products where most consumed products are based on refined cereal grains known to be nutritionally limited. Furthermore, an overview of the opportunities, challenges, and future developments of the utilisation of immature cereals grains and their products was highlighted.
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.
Performance of carrots under various fertilization and water application regimes
(Sokoine university of agriculture, 2022) Alexandre, Ciza
Carrot (Daucus carota L.) is a crop cultivated in Tanzania, but its productivity is still low, mainly due to poor agronomic practices and limited information on optimal levels of water along with type and level of fertilizer application that enhance crop production. Thus, the main objective of this study was to evaluate the effect of carbonate foliar application (lithovit), soil-based NPK fertilizer application and various levels of water application on the growth, yield and quality of carrots under the semi-arid conditions of Morogoro in Tanzania. Various water application levels in the first season (96.6 m 3 for 100% (I 100 ), 77.28 m 3 for 80% (I 80 ) and 57.96 m 3 for 60% (I 60 )) equivalent to 475.83 mm, 380.67 mm, and 285.498 mm and in the second season (47.34 m 3 for 100% (I 100 ), 37.872 m 3 for 80% (I 80 ) and 28.404 m 3 for 60% (I 60 )) equivalent to 233.64 mm, 186.92 mm, and 140.19 mm, respectively, with different rates of lithovit (1, 1.5 and 2 g/L/plant) and 150 kg NPK ha -1 were applied. The experiment was set as a 3×6 factorial in a split plot design. ANOVA on the growth, yield, and quality parameters was done with the aid of Genstat statistical software. NPK soil-based fertilizer application level of 2 g/plant under full irrigation, represented by the replenishment of 100% of ET c , appears to be optimal for carrot production. Full irrigation was found to be superior to other levels for carrot production. The interaction between full irrigation and the 2 g/plant fertilizer rate of soil-based NPK fertilizer enhanced carrot production compared to other interactions. Foliar fertilizer may not satisfy the complete nutrient requirement of the crop; further study on carrot productivity should be conducted using soil-based NPK fertilizer and foliar fertilizer in combination with organic fertilizers under various water application levels for comparative purposes.
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.
Implications of ecological gradients and climate change on tree species composition, diversity and distribution in two eastern arc mountains, Tanzania
(Sokoine University of Agriculture., 2014) Chitiki, Alfred
The conservation of biological diversity in the tropics is important for improving ecosystem goods and services. Proper conservation planning however requires a thorough understanding of forest ecosystem processes that give rise to observed diversity and distribution patterns. Such knowledge may reflect underlying ecological processes that are important for management. Within forest ecosystems, plant communities have been associated with biotic and abiotic factors that often interact to form complex network of relationships. However, few attempts have addressed the questions of environmental effects to tree communities in the tropics with particular emphasis on the Eastern Arc Mountains (EAMs) of Tanzania. With recent environmental change, such ecosystems and component species are expected to respond uniquely, raising special conservation concerns. This study was carried out with the overall objective of determining tree species composition, diversity and distribution patterns in the Udzungwa (UMF) and East Usambara (EUF) Mountain forests of the EAMs as influenced by environmental gradients and climate change. Multivariate and Maximum Entropy Distribution Modelling (Maxent) was used in data analysis. High species richness was observed at mid-elevations suggesting that most of the species occur at moderate climatic conditions where growth and survival conditions are at optimal. There was a mixed response in species composition to mean annual temperature suggesting a heterogeneous effect of temperature on these two afromontane forests. The effects of edaphic factors appeared to be crucial in determining plant community patterns in the EAMs. Climatic and edaphic factors were predicted to be the main drivers of species distribution under current and future environmental conditions. Some species were predicted to lose their suitable habitats while others would gain through habitat (niche) expansion in response to climate change. Gradual variations in diversity responses to temperature for the two EAM sites suggest a need to focus on local patterns of climate change rather than broad-scale assessments. Conservation planners are advised to focus on local patterns of climate change and avoid broad-scale generalizations in assessment of how climate change might impact tree communities.
Modelling and measurement of soil moisture content based on a remote sensing method for applications in Semi-arid tropics.
(University of Bonn, 1999-06-18) Salim, Baanda A.
Soil moisture plays a very crucial role in land surface processes It should therefore be monitored with the same accuracy and frequency as other important environmental variables Two approaches are used for estimation of soil moisture content, namely, modelling and measurement, either in-situ or remote. Integration of modelling and measurements may provide the best solution towards estimation of soil moisture content The utility of ground-based thermal infrared remote sensing method for the estimation of nearsurface soil water content was tested under tropical semi-arid agricultural conditions in Morogoro, Tanzania, East Africa Field experiments were conducted between January and August, 1997 at a bare soil site Regression relationships between the daily maximum surface soil temperature minus air temperature (TDMax) and weighted-average soil water contents to different depths in the soil profile were developed based on the measured data Better correlations were obtained for the top 0-5 and 0-15 cm layers of the soil, with coefficients of determination ofO 81 and 0.78, respectively Use of "Normalized TDMax" as well as cloudncsscover- correctcd "Normalized TDMax” (TDaMax) resulted in even better coefficients of determination (c g , 0 95 for the 5 cm depth) A physically based model of coupled flow of heat and water in the soil (SUAHEAT) was developed The SUAHEAT model was tested by comparing its simulated soil water contents and soil temperatures with those measured at the bare soil site Both qualitative as well as quantitative methods were used to evaluate the model performance, for the calibration and validation phases For the calibration phase, the average values of the mean absolute difference (MAD) of soil water content were 0.06, 0 05, 0 05, and 0.03 m7nP for the 5, 15, 30, and 45 cm depths, respectively The corresponding average values of the root mean square difference (RMSD) of soil water content were 0.07, 0 06. 0 05, and 0 03 m’/m’ for the same depths, respectively As for the validation phase, the average MAD values of soil water content were 0 09, 0.05, 0 08, and 0 17 nP/nP for the same depths, respectively. The corresponding average RMSD values for the same depths were 0 12. 0 08, 0 10, and 0 19 nP/nP, respectively The unusually large errors (at the 45 cm depth) during the validation phase could be attributed to the overestimation of soil water content values during very wet conditions arising from the calibration equation used. The performance of the model in the simulation of surface, near-surface, and profile soil temperatures was also both qualitatively and quantitatively evaluated In the calibration phase, the MAD values were 2 8, 1 1,0 5, and 0 3 °C for the 5, 15. 30, and 45 cm depths, respectively. The corresponding RMSD values for the same depths were 3 5, 1.3, 0.6, and 0.4 °C, respectively. For the validation phase, the MAD values for the same depths were 2.3, 1 2, 0 7, and 0.4 °C, respectively. The corresponding RMSD values for the same depths were 2.7, 1.4, 0.8, and 0.5 °C, respectively. Generally, the errors obtained with the use of the SUAHEAT model are comparable to values obtained by other researchers elsewhere using similar models. Integration of the model with remotely sensed surface soil water content and temperature data was effected through use of the initial profiles of soil water content and temperature. The initial profile data were derived from the regression relationships between TDMax and surface soil water content on the one hand, and between the surface and profile soil temperatures on the other, respectively. Model simulation results obtained using the remotely sensed initial conditions indicated that it is feasible to use remotely sensed data (one value of TDMax per day) to initialize the model Similarly, extrapolation of the remotely sensed near-surface (0-5 cm depth) soil water content to values at greater depths in the soil profile was shown to be feasible.
The influence of age, size and sex on feeding in yellow baboons: sexual segregation but not as we know it
(Anglia Ruskin University, 2016) Kitegile, Amani
Yellow baboons are sexually size dimorphic mammals living in permanent stable mixed- sex troops: Puzzling in the context of our current theory on group living, sexual dimorphism and sexual segregation! This study is the first to investigate how male and female baboons live together despite body size differences. It hypothesizes they use subtle differences in diet and behaviour predicting that Subadult males will be more similar to adult females than larger bodied adult males. Testing this required looking at the behaviour of baboons in new ways by building on long-term research in an area high in abundance and diversity of baboon food species and habitats in Mikumi National Park (Tanzania) Data on dietary profile, space use and activity budgets from three-age-sex classes were collected using focal follows with instantaneous and one-zero recording: 70 individuals in 2 troops, over 270 days across 2 years. Findings demonstrate that baboon diets are diverse not just in terms of species. A range of plant parts and types (including sap and forbs) were eaten plus vertebrates and, especially, invertebrates. Food was packaged in a variety of ways with different processing requirements. Exotic food from a highway was also eaten although only made a very minor contribution to overall diet. Subadult males were more similar to adult females than adult males in their dietary profile (particularly in terms of parts and packages) and activity budgets (particularly in terms of relative allocation of time and number of activities but not synchrony). There were differences between age-sex classes in space use but no consistent patterns emerged. These findings suggest that adult male and female baboons are able to live together and avoid “classic” sexual segregation despite large difference in body size by subtle differences in what they eat but not in where and how they allocate their time for feeding.
Silicon uptake by rice plant under the system of rice intensification and continuous flooding in Mkindo Irrigation Scheme, Morogoro, Tanzania
(Sokoine University of Agriculture, 2021) Gowele, Grace Erasto
Silicon (Si) is the second most abundant element available in the earth's crust and is considered as a beneficial element for crop growth especially rice. Si deficiency in the soil may lead to decline in rice yields. A study was conducted in Mkindo Irrigation Scheme, Morogoro, Tanzania to assess Si uptake by rice plant grown under the system of rice intensification and continuous flooding. The experiment was laid out in a randomized complete block design (RCBD) with two treatments which were two water application regimes T 1 and T 2 . T 1 was alternate wetting and drying using SRI technology and T 2 was continuous flooding. The treatments were replicated three times and the rice variety used was SARO 5 (TXD 306). The experiment was conducted in two seasons from October 2019 to January 2020 and from March 2020 to June 2020. The available Si status in soils of the experimental site, in rice seeds, grains and in rice plant leaves as well as growth and yield parameters were assessed according to elemental analysis based on Energy Dispersive X- Ray Fluorescence and results were analyzed using GENSTAT software. The soils of the study area had sufficient amount of available Si content which ranged from 230.58 to 240.42 mg kg -1 . Si content in rice seeds observed prior to the experiment was within acceptable range between 4-20%. Si content in rice grains was gradually increasing during reproductive stage and later dropped during harvest. Si content in rice plant leaves increased from vegetative to ripening stage whereby T 1 gave the highest Si content (12.37%) while the lowest value (10.15%) was observed in T 2. Similarly, T 1 recorded the highest plant height (147 cm), number of tillers per hill (54), number of productive tillers per hill (46), number of panicles per hill (31) and grain yield (8 tons ha -1 ) meanwhile T 2 gave the lowest plant height (129 cm), number of tillers per hill (27), number of productive tillers per hill (22), number of panicles per hill (27) and grain yield (3 tons ha -1 ). It was concluded that, SRI enhanced adequate uptake of Si which in turn improved significantly crop growth and rice yield compared to continuous flooding practices.
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.
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.
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.
Performance evaluation of Dakawa irrigation scheme Morogoro Tanzania
(Sokoine University of Agriculture, 2020) Makaka, F.P
Many irrigation schemes which have been built in Tanzania are performing below standard. This situation has resulted in low scheme production. Major causes for poor performance may vary between different schemes. However, a comprehensive performance evaluation of these schemes may bring a common understanding on the way to improve the performance and enhance crop productivity in the irrigation schemes. This Study was conducted to evaluate the overall irrigation performance of a cooperate irrigation scheme in Dakawa Irrigation Schemes. In this scheme, water abstraction weir was designed and constructed along Wami river to deliver water to a main canal in a typical cooperate irrigation schemes. Flows to each of the secondary canals were measured using calibrated staff gauges. The discharge data along with climatic data was used in computing overall irrigation performance, irrigation water supply, distribution performance, productivity of land and water, equity of irrigation water supply, relative water supply, relative irrigation supply, water delivery capacity and irrigation ratio. Moreover, social economic survey was also conducted to assess financial self-sufficiency, fee collection, relative water costs, technical knowledge of staff and sustainability of irrigable area. Irrigation performance indicators were also used to compare performance among different cultivated areas. Review of documents, key informant interviews, focus group discussions and field measurements was administered to collect information on irrigation and land use practiced by farmers. The results show that the main canal supplied 4160 l/s of water for irrigation to all secondary canals which uses 4003 l/s during the cropping season to meet crop demand for the entire irrigation scheme. However, the farmers at the head and middle reaches abstracted more water than they required and consequently caused a shortage of water supply to farmers at the tail-end reach. The result also shows that the overall coefficient of variation in the discharge of water to al secondary canals was within the acceptable range which is 67%. This adequate coefficient of variation was due to improvements done in the whole scheme area including the pump house. The seasonal equity of water distribution in secondary canals in Dakawa was considered fair because all eight secondary canals equity values were above 62.5 percent. The productivity of land and output per command area in the Dakawa scheme is 8 198 346 US$. High productivity could be attributed to use of high–level inputs including sub-optimal cropping intensities. The relatively high values of output per irrigation supply suggest that the efficiency with which water is being used in the scheme is high. From the focus group discussion, it was found out that farmers still have limited understanding of irrigation scheduling and irrigation water management, as a result, some areas were overirrigated while others faced water shortage. This situation calls for more farmers training to be conducted in the Dakawa Irrigation Scheme. Same actions may be considered to other existing irrigation schemes in Tanzania.
Uncertainity reduction in climate and hydrological models predictions at catchment scale in the upper great Ruaha river sub-basin, Tanzania
(Sokoine University of Agriculture, 2019) Mutayoba, E. I.
Water resources have become scarce in most tropical areas of Tanzania due to climate change. Any changes to the hydrological cycle may have significant effects on the water resources in the river basins of Tanzania. The impact of climate change on water resources in Tanzania have been studied using General Circulation Models (GCM) which run at low spatial resolutions of 100-300 km. The resolution is too coarse to provide useful information about climate change impact in small catchments as many physical processes which control local climate e.g.; vegetation, hydrology, topography is not fully parameterized and hence results on uncertainty in model prediction. The main aim of this research was to quantify the uncertainty in model predictions for the Mbarali River Sub-catchment of the Upper Great Ruaha River Sub-basin in the Rufiji River Basin, Tanzania. Three research objectives were analyzed; the first objective was to evaluate the performance of the Coordinated Regional Downscaling Experiment Regional Climate Model (CORDEX, Regional Climate Models) in simulating rainfall characteristics of the Mbarali River Sub catchment. The area weighted average method was used to calculate the average rainfall from the CORDEX RCMs and from ERA-Interim reanalysis over the entire Mbarali River sub-catchment. Comparison between rainfall data from CORDEX RCMs and ERA-Interim reanalysis was done to test the ability of the CORDEX RCMs to reproduce the annual cycles, interannual variability, annual total and trends of rainfall as presented by the ERA-Interim reanalysis. The second objective assessed the impact of climate change on hydrological characteristics using the Soil and Water Assessment Tool (SWAT) model. The ability of the SWAT model to simulate catchment processes was assessed through a calibration and validation process, which was a key factor in reducing uncertainty and increasing user confidence in its predictive abilities. The SWAT model was driven by high resolution climate simulations for historical climate condition (1971-2000) as well as future climate projections (2011-2040, 2041-2070 and 2071-2100) for two Representative concentration Pathways (RCPs): RCP 4.5 and RCP 8.5. Furthermore, Ensemble of RCMs was applied into SWAT to simulate water resources availability and the results were compared with individual models (HIRHAM5, CCLM4, RACMO22T, RCA4). The Rainfall and Temperature data were obtained from the selected four CORDEX RCMs driven by three different General Circulation Models (GCMs). Inverse Distance Weight Average (IDWA) was used to interpolate model gridded climate simulation to the location of weather station. The third objective assessed the impacts of land use and land cover change on the hydrology using integration of remote sensing data, QGIS and SWAT model. The land use and land cover (LULC) maps for three window period snapshots, 1990, 2006 and 2017 were created from Landsat TM and OLI_TIRS. Supervised classification was used to generate LULC maps using the Maximum Likelihood Algorithm and Kappa statistics for assessment of accuracy. The findings of the first objective are that CORDEX RCMs were able to capture well the seasonal and annual cycles of rainfall. However, they underestimated the amount of rainfall in March, April and May (MAM) and overestimated in October, November and December (OND) respectively. CORDEX RCMs reproduce interannual variation of rainfall. The source of uncertainties was revealed when the same RCMs driven by different GCMs and when different RCMs driven by the same GCM in simulating rainfall. It was found that the error and biases from RCMs and driving GCMs contribute roughly equally. Overall, the evaluation found reasonable (although variable) model capability in representing the mean climate, interannual variability and rainfall trends. The results suggest that CORDEX RCM is suitable in simulating rainfall, maximum temperature and minimum temperature. The findings of the second objective showed that SWAT model simulated stream flow and water balance components differently when two different RCMs were forced by the same GCMs as well as when the same RCMs were forced by different GCMs. The differences are related to the formulation of the RCMs themselves. For example, RACMO22T and HIRHAM5 driven with the same GCM (ICHEC-EARTH) simulate different amount of stream flows, surface runoff, water yield and groundwater yield in historical (1971–2000) as well as in present century (2011-2040), mid-century (2041- 2070) and end century (2071-2100). Ensemble RCMs projected decrease in stream flows by 13.67% under RCP 8.5. However annual rainfall was shown to increase in averages by 1.62% under RCP 4.5 and by 1.96% for RCP 8.5 relative to the 1177.1mm of the baseline period (1971-2000). The results also showed that, temperature will slightly increase relative to the baseline during present century (2011-2040) for RCP 4.5 and RCP 8.5. The ensemble average project that the minimum temperature will increase by 14% (1.9 0 C) under RCP 8.5 and maximum temperature by 7.68% (1.8 o C) under RCP 4.5 The findings of the third objective showed that there were significant changes in land use and cover for the three-time periods (1990, 2006 and 2017). The cultivated land and built up area increased from 25.69% in 1990 to 31.53% in 2006 and 43.57% in 2017 compared to other land classes. Increase of cultivated land and built up area led to decrease in forest cover. Forests occupied 7.54% in 1990, but decreased to 5.51% in 2006 and 5.23% in 2017. This decrease in forest cover has resulted in increased surface runoff for the same periods (2006-2017). The increase in surface runoff in the study area could be attributed to deforestation and poor land husbandry, where during land preparation much of the vegetation is cleared, hence decreasing canopy interception and allowing water to drain off. Also, poor farming practices including cultivation on hillslopes without soil conservation, reducing soil compaction, hence allowing more water to drain as surface runoff. The calibrated SWAT model using the three different land use and land cover change of 1990, 2006 and 2017 indicate that during the wet season, the mean monthly flow increased by 1.48% relative to the 28.09 m 3 /s of the baseline 1990 while during the dry season, the mean monthly flow decreased by 16.7% relative to the 0.20 m 3 /s baseline flow. Assessment of the impacts of land use and land cover changes on catchment water balance component revealed that surface runoff increased by 3.9% in 2006 and 9.01% in 2017 while groundwater contribution to stream flow decreased by 6.3% and 12.86% in 2006 and 2017, respectively. The decrease in stream flow could also be attributed to abstraction of water for irrigation activities upstream of the Igawa gauge station. The findings of the study may help basin water officers, planners in water sector and agriculture sector in addressing uncertainty in policy and decision-making specifically when preparing strategies and adaptations plans for river catchment. The science used in this study can be applicable to another river basin in Tanzanian in a climate change impact study.
Uncertainity reduction in climate and hydrological models predictions at catchment scale in the upper great Ruaha river sub-basin, Tanzania
(Sokoine University of Agriculture, 2019) Mutayoba, E. I.
Water resources have become scarce in most tropical areas of Tanzania due to climate change. Any changes to the hydrological cycle may have significant effects on the water resources in the river basins of Tanzania. The impact of climate change on water resources in Tanzania have been studied using General Circulation Models (GCM) which run at low spatial resolutions of 100-300 km. The resolution is too coarse to provide useful information about climate change impact in small catchments as many physical processes which control local climate e.g.; vegetation, hydrology, topography is not fully parameterized and hence results on uncertainty in model prediction. The main aim of this research was to quantify the uncertainty in model predictions for the Mbarali River Sub-catchment of the Upper Great Ruaha River Sub-basin in the Rufiji River Basin, Tanzania. Three research objectives were analyzed; the first objective was to evaluate the performance of the Coordinated Regional Downscaling Experiment Regional Climate Model (CORDEX, Regional Climate Models) in simulating rainfall characteristics of the Mbarali River Sub catchment. The area weighted average method was used to calculate the average rainfall from the CORDEX RCMs and from ERA-Interim reanalysis over the entire Mbarali River sub-catchment. Comparison between rainfall data from CORDEX RCMs and ERA-Interim reanalysis was done to test the ability of the CORDEX RCMs to reproduce the annual cycles, interannual variability, annual total and trends of rainfall as presented by the ERA-Interim reanalysis. The second objective assessed the impact of climate change on hydrological characteristics using the Soil and Water Assessment Tool (SWAT) model. The ability of the SWAT model to simulate catchment processes was assessed through a calibration and validation process, which was a key factor in reducing uncertainty and increasing user confidence in its predictive abilities. The SWAT model was driven by high resolution climate simulations for historical climate condition (1971-2000) as well as future climate projections (2011-2040, 2041-2070 and 2071-2100) for two Representative concentration Pathways (RCPs): RCP 4.5 and RCP 8.5. Furthermore, Ensemble of RCMs was applied into SWAT to simulate water resources availability and the results were compared with individual models (HIRHAM5, CCLM4, RACMO22T, RCA4). The Rainfall and Temperature data were obtained from the selected four CORDEX RCMs driven by three different General Circulation Models (GCMs). Inverse Distance Weight Average (IDWA) was used to interpolate model gridded climate simulation to the location of weather station. The third objective assessed the impacts of land use and land cover change on the hydrology using integration of remote sensing data, QGIS and SWAT model. The land use and land cover (LULC) maps for three window period snapshots, 1990, 2006 and 2017 were created from Landsat TM and OLI_TIRS. Supervised classification was used to generate LULC maps using the Maximum Likelihood Algorithm and Kappa statistics for assessment of accuracy. The findings of the first objective are that CORDEX RCMs were able to capture well the seasonal and annual cycles of rainfall. However, they underestimated the amount of rainfall in March, April and May (MAM) and overestimated in October, November and December (OND) respectively. CORDEX RCMs reproduce interannual variation of rainfall. The source of uncertainties was revealed when the same RCMs driven by different GCMs and when different RCMs driven by the same GCM in simulating rainfall. It was found that the error and biases from RCMs and driving GCMs contribute roughly equally. Overall, the evaluation found reasonable (although variable) model capability in representing the mean climate, interannual variability and rainfall trends.The results suggest that CORDEX RCM is suitable in simulating rainfall, maximum temperature and minimum temperature. The findings of the second objective showed that SWAT model simulated stream flow and water balance components differently when two different RCMs were forced by the same GCMs as well as when the same RCMs were forced by different GCMs. The differences are related to the formulation of the RCMs themselves. For example, RACMO22T and HIRHAM5 driven with the same GCM (ICHEC-EARTH) simulate different amount of stream flows, surface runoff, water yield and groundwater yield in historical (1971–2000) as well as in present century (2011-2040), mid-century (2041- 2070) and end century (2071-2100). Ensemble RCMs projected decrease in stream flows by 13.67% under RCP 8.5. However annual rainfall was shown to increase in averages by 1.62% under RCP 4.5 and by 1.96% for RCP 8.5 relative to the 1177.1mm of the baseline period (1971-2000). The results also showed that, temperature will slightly increase relative to the baseline during present century (2011-2040) for RCP 4.5 and RCP 8.5. The ensemble average project that the minimum temperature will increase by 14% (1.9 0 C) under RCP 8.5 and maximum temperature by 7.68% (1.8 o C) under RCP 4.5 The findings of the third objective showed that there were significant changes in land use and cover for the three-time periods (1990, 2006 and 2017). The cultivated land and built up area increased from 25.69% in 1990 to 31.53% in 2006 and 43.57% in 2017 compared to other land classes. Increase of cultivated land and built up area led to decrease in forest cover. Forests occupied 7.54% in 1990, but decreased to 5.51% in 2006 and 5.23% in 2017. This decrease in forest cover has resulted in increased surface runoff for the same periods (2006-2017). The increase in surface runoff in the study area could be attributed to deforestation and poor land husbandry, where during land preparation much of the vegetation is cleared, hence decreasing canopy interception and allowing water to drain off. Also, poor farming practices including cultivation on hillslopes without soil conservation, reducing soil compaction, hence allowing more water to drain as surface runoff. The calibrated SWAT model using the three different land use and land cover change of 1990, 2006 and 2017 indicate that during the wet season, the mean monthly flow increased by 1.48% relative to the 28.09 m 3 /s of the baseline 1990 while during the dry season, the mean monthly flow decreased by 16.7% relative to the 0.20 m 3 /s baseline flow. Assessment of the impacts of land use and land cover changes on catchment water balance component revealed that surface runoff increased by 3.9% in 2006 and 9.01% in 2017 while groundwater contribution to stream flow decreased by 6.3% and 12.86% in 2006 and 2017, respectively. The decrease in stream flow could also be attributed to abstraction of water for irrigation activities upstream of the Igawa gauge station. The findings of the study may help basin water officers, planners in water sector and agriculture sector in addressing uncertainty in policy and decision-making specifically when preparing strategies and adaptations plans for river catchment. The science used in this study can be applicable to another river basin in Tanzanian in a climate change impact study.
Influence of vegetation communities on small mammal abundance and diversity in an agro-ecosystem in Isimani division, Iringa Region, Tanzania
(Sokoine University of Agriculture, 2018) Lyamuya, J. V.
Vegetation communities are home for a number of animals including small mammals, hence any change in vegetation communities will influence their abundance and spatial distribution. This study aimed at investigating the influence of vegetation communities on small mammal abundance and diversity in Isimani agroecosystem landscape, southern Tanzania. Three study sites selected based on landscape characteristics and vegetation communities were investigated, classified and mapped. Fourteen vegetation communities were mapped and more than 80 trees species and 20 species of herbs were identified during the field survey. A total of 63 Small mammals trapping sites were randomly located in the three sites covering 188 km2 where 507 small mammals of eight different species were trapped. The data obtained were later analysed to get an insight into their relationship. Boosted Regression Trees (BRT) modelling technique was used to establish the relationship between vegetation communities and small mammal abundance and diversity. Small mammals were found in large numbers in cultivated fields and fallowed areas. Trap success was high at high altitudes i.e. on the plateau, shamba rat i.e. Mastomys natalensis contributed for more than 80% of the total number of small mammals recorded. BRT model results showed that altitude was the most important vegetation communities’ predictor variable contributing 45.6% on small mammals’ abundance and (80.2%) on their diversity. Identification and mapping of different vegetation communities across agroecosystem landscape has proven to be very crucial for understanding vegetation - small mammals interactions in agroecological landscapes. This study recommend measures that reduce herbaceous vegetation from fallowed areas and encourage woody vegetation to be taken in order to supress grasses in vegetation bordering farms so as to achieve Ecological Based Rodent Management (EBRM). Also future studies that will investigate how small mammal abundance and diversity can be influenced by different vegetation communities seasonally in agroecological landscapes.
Land use/land cover dynamics and their impact on pastoralism: a case study of Melela ward, Mvomero district, Morogoro Tanzania
(Sokoine University of Agriculture, 2018) Kwayu, R.
Studies which have been conducted so far have focused on the processes of land use/land cover changes in different areas at regional and global levels. Not much has been done to quantify the factors that influence land use/land cover dynamics in Melela ward, Mvomero District, Morogoro, Tanzania. The main objective of the current study was to evaluate land use land cover dynamics and their impacts on pastoralism in Melela. Specifically, the study examined land use/land cover dynamics for the period from 1991 to 2016, to identify socio-economic factors that influence land use/land cover dynamics and to determine the effects of land use/land cover dynamics on pastoral community livelihood and production potential. Remote sensing and GIS techniques were used for data collection and change detection analysis was employed to assess the spatial and temporal land use/land cover change of the study area. Quantitative methods including descriptive statistics was used for analysis of social economic drivers and its impacts on pastoral community livelihood and production potential. The results were the matrices and the categories of land use/land cover changes. The study findings indicate a significant change in LULC as evidenced by an increase in agriculture and a loss of woodland. The period 2000-2016 has shown gains in agriculture and losses of woodland areas. Changes in the crops grown, increased immigration of pastoralists, population growth, charcoal burning, and livestock keeping have contributed to an overuse of the existing land resources, which resulted in significant variations in the spatio - temporal patterns of land use. The assessment of changes in the grazing land in Melela has shown that the current patterns would increase the population of pastoralists in the region, through an increase of immigrants among the pastoralists and grazing pressure. The results of this study quantify dynamics of land use/land cover and its drivers on sustainable use of land. In the face of increasing population size, pastoralism, and charcoal burning, there is need of maintaining a balance for socio- economic drivers and sustainable utilization of land use.

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