Department of Biociences

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Analysis of the current and future land use/land cover changes in peri-urban areas of Dar es salaam city, Tanzania using remote sensing and GIS techniques
(College of Natural and Applied Sciences, University of Dar es Salaam, 2021) Mnyali, Erick T.; Materu, Silvia F.
A rapid increase in population and urban development has direct impacts on the natural environment of peri-urban areas of big cities, especially in the developing countries. This study examined land use and land cover changes (LULCC) of peri-urban areas of Kinondoni Municipality in Dar es Salaam city for the period between 1999 and 2019 and predicted future changes by 2039. The specific objectives were to; (i) map the spatial-temporal land use and cover changes (ii) analyze settlements (built-up areas) patterns and factors influencing their changes (iii) predict changes that might happen for the next two decades. LULCC for 1999 to 2019 were detected through Maximum Likelihood (ML) supervised classification techniques while Cellular Automata based on Artificial Neural Network (CA-ANN) model was used to predict future changes. Over the past two decades, 33.7% of vegetation has been lost due to increased settlements, as shown by linear development pattern of built-up areas, which has gained about 30% of other land covers. This study predicts that by 2039, built-up areas will increase drastically to occupy 51.6%, while vegetation and water cover will decrease to occupy 40.4% and 1.4%, respectively. Without good planning strategies and land use policies, the control and management of the magnitude and patterns of peri-urban growth and sustainable management of natural and built environments in Tanzania will remain a challenge. This paper seeks to contribute to the body of knowledge required for evidence-based policy formulation and decision making to attain sustainable urbanization through setting suitable management plans for peri-urban areas of Tanzanian cities.
Analyzing aspects of land-use sustainability in Tanzania: Current forest degradation, urban charcoal demand, and impacts of future firewood and charcoal consumption
(Norwegian University of Life Sciences, 2019) Nyamoga, Greyson Zabron
The forest sector plays a significant roles both directly and indirectly in Tanzania. In total 54% of the land area of mainland Tanzania is covered by different types of forests, the main ones being the miombo woodlands, woodland mosaics, mangrove and the tropical or rain forests with closed canopy. Forestry supports directly or indirectly other sectors including agriculture and tourism through provision of habitats for wildlife, water resources and catchments as well as maintaining hydrological balance and soil protection. It plays significant roles in biodiversity protection and recycling atmospheric gases, and provides construction materials, income and employment opportunities. 7’anzania’s wood harvest volume is difficult to estimate, but according to FAO official statistics the country’s total annual harvest of wood in 2014 was about 40 mill m3 of which more than 93% was used for firewood or charcoal production. In Tanzania, more than 90% of the population use fuelwood (i.e. charcoal and firewood) as main source of energy. Most of this fuelwood is supplied from the miombo woodlands which covers about half of the forest area in mainland Tanzania. The country’s demand of forest products is strongly increasing due to substantial economic and population growth and increased urbanization. Currently the population growth is 2.7% p.a., the economic growth is 6.9% p.a. while the urban population growth is about 5% p.a. Such growth rates imply increasing pressure on forest lands and forestry. Charcoal and firewood are key products from the forest in Tanzania and are the country’s main fuels for cooking, with charcoal mainly used in urban areas. Production and consumption of charcoal and firewood play a significant role in enhancing the livelihoods of people, but may also lead to adverse environmental impacts. In Tanzania, large uncertainties exist about the present quantities of fuelwood consumed, as well as about the future integrated development of fuelwood demand and supply. The main objectives of this study are to improve the knowledge base regarding the present and future production and consumption of charcoal and firewood in Tanzania and their impacts on forest sustainability. More specifically, the thesis addresses the following research questions: Qi. What is the extent of land degradation and land rehabilitation potential in Tanzania? Qz. Which information do previous studies provide about charcoal and firewood production and consumption in Tanzania? Q3. What are the effects of price, income and household size on charcoal consumption in the three Tanzanian urban areas Dodoma, Morogoro and Mtwara? Q4. T o what extent is it possible to: (i) develop a dynamic forest sector partial equilibrium model for mainland Tanzania which consistently links forestry data regarding tree species, forest growth and growing stock from about 32,000 single plots in Tanzania's national forest inventory NAFORMA, with socio-economic data regarding the country’s present and future consumption and production of charcoal and firewood; and (ii) apply this model for analyzing how assumptions regarding population growth, urbanization rate and economic growth would influence the future consumption and production of firewood, charcoal and poles, forest resource use, and forest sustainability? In this thesis those questions are addressed in four papers, one for each question. Most efforts have been made in developing the quantitative model described in Q4, and issues related to theories of land-use or policy analyses are only briefly discussed. Below follows a summary of the papers and chapters 4 and 5 of the synopsis. Paper 1 aims at (i) assessing the potential for land rehabilitation in various regions of Tanzania based on new data from NAFORMA, and (ii) reviewing main experiences and economic results gained in previous land rehabilitation studies in the country. It is found that about 49% (43.3 mill ha) of the total land area in mainland Tanzania is under either light (43%, 37.7 mill ha), moderate (5%, 4.4. mill ha) or heavy (1.3%, 1.2 mill ha) erosion. These figures are substantial and imply large opportunities for land rehabilitation. The present land degradation is high, and parts of the degraded areas could be reforested, thus giving increased sustainable supply of forest and food products and maintaining environmental benefits, including increased carbon sequestration for global climate change mitigation. Very few economic studies are found on the benefits and costs of land rehabilitation in Tanzania, and new studies are highly needed in order to identify and prioritize among the potential rehabilitation activities. In Paper II, a review is presented of studies of charcoal production and consumption in Tanzania, and promising new research tasks are identified. Many interesting and valuable studies have been done, and it is clearly seen how important charcoal consumption and production are both in a social, ecological and economic perspectives. However, the results of the studies diverge a lot and most of the reviewed studies lack clear hypotheses and specifications of behavior theories to be used for developing realistic and testable hypotheses. It is found that more research is needed on factors effecting charcoal demand - like changes in prices, income and policies, and for that, using national household surveys is recommended. More research is also needed about tree regeneration (time and volumes) in miombo woodlands; how various forms of land ownerships influence miombo woodlands management; the possibilities and preferability in Tanzania of establishing forest plantations for producing charcoal; total and distributional impacts of policies related to production or consumption of fuelwood; climate gas emission impacts of charcoal production and consumption; development of bio-economic models which make possible consistent analyses of ex ante defined possible changes from the present socio-economic and policy situation. In Paper III, results are presented from a survey of 360 households in the three Tanzanian cities Dodoma, Morogoro and Mtwara about the impacts of income, charcoal prices and household size on the household per capita charcoal consumption. For the total sample, statistically significant elasticities for charcoal per capita consumption were found to be 0.03, -0.13 and -0.62 for respectively per capita income, charcoal price and household size. In the low income group, statistically significant elasticities for annual charcoal per capita demand were found to be - 0.44 and -0.59 for respectively charcoal price and household size; in the middle income group only household size was found to be statistically significant with estimated elasticity -0.81; and in the high income group elasticities of 0.17 for per capita income and -0.44 for household size were found statistically significant. These results are based on small samples and should be viewed as exploratory results of value primarily as information for larger surveys. Paper IV has as primary objectives to develop a forest sector model which integrates wood supply from detailed forest data from Tanzania’s NFI (National Forest Inventory) NAFORMA with demand for wood products, and apply this model to evaluate sustainability impacts of the future production and consumption of firewood, charcoal and poles in mainland Tanzania. The developed model (TanzFor) is classified as an intertemporally optimized spatial equilibrium model, and links in an economic consistent framework supply and demand for fuelwood, poles and charcoal as well as forest industry products. The study is the first one applying this kind of model in Africa with data from a detailed NFI as NAFORMA and newly developed forest growth functions as basis for the wood supply. The model results show alarming negative impacts on forest growing stocks by the steadily increasing consumption of firewood and charcoal in Tanzania, mainly caused by high population growth, high urbanization rates, low utilization efficiencies in both charcoal production and consumption, and rather free access to forest land. Chapter 4 of the synopsis gives a more overall, perspectively oriented discussion of the results obtained in Papers I-IV, focusing on uncertainty, linkages between the four thesis papers, connections to land use theories, relevance of forest sector modeling in Tanzania, policy implications and future research. The following topics are mentioned as being among the most interesting ones for future research: Further use of the NAFORMA data in fuelwood analyses; provide more accurate data on the present and future consumption of charcoal and firewood; analyze wood supply impacts of various kinds of property right regimes and policy means; improving forest sector modelling in Tanzania both regarding data input quality and incorporation of land property/ownership specifications; applying the model in estimating GHG emission and impacts of climate change in the forest sector; using the model in estimating impacts of policy means. It is emphasized, however, that like all models TanzFor has weaknesses and is a simplification of real life conditions, and that all TanzFor model results should be interpreted with that in mind. In Chapter 5 it is concluded that the above mentioned four research questions Q1-Q4 have been addressed and new results obtained which clearly show that the current consumption of wood in Tanzania is not sustainable. Tanzania is experiencing high and increasing production and consumption of charcoal particularly in urban areas where charcoal is the main type of energy for cooking. The results in this thesis indicate that challenges of fuelwood production and consumption will remain large in Tanzania for quite some time if no measures are taken to make cooking energy substitutes to charcoal more reliable and affordable than at present, and the charcoal production more efficient.
Applicability of a biotest battery developed for temperate regions to tropical environments: implications for sustainable wetland management – a Case study of Kilombero Ramsar Site
(Leuphana Universität Lüneburg, 2015-04) Materu, Silvia F.
The increasing rate at which chemicals are released into the environment in Africa over the past two to three decades has raised a concern about the immediate ecological impacts and associated long-term environmental risks. Toxicity tests, which measure responses of organisms to various contaminants, have the capacity to indicate ecological impacts of chemicals that are released into the environment, and are therefore used in risk assessment studies. Intensive eco-toxicological studies in the developed world have led to establishment of standardized biotest procedures in order to assure reproducible and reliable results for risk assessment and for environmental regulations. Although there are a lot of data and publications on water and sediment quality for temperate countries using bioassays, tropical ecological risk assessment data using bioassays are scarce. The focus of this study was to apply biotests developed in temperate countries on tropical samples and evaluate their suitability for assessing pesticide contamination in soil, water, and sediment from Kilombero Valley Ramsar Site, in Tanzania. A total number of 143 dry and rainy season samples (58 water, 68 sediments and 17 soils) was collected in eight plantations (sugarcane, rice and teak). Toxicities were assessed by a battery of standardized tests comprising the algae growth inhibition test with the freshwater green algae, Pseudokirchneriella subcapitata, the luminescence bacteria test with Vibrio fischeri, and the bacterial sediment contact test with Arthrobacter globiformis. Responses of test organisms to sample matrices were categorized and classified into toxicity classes according to a fuzzy rule based-expert system. Suitability of using the P. subcapitata bioassay for assessing pesticide contamination in tropical agronomic systems based on the results of this study was evaluated. Chemical, geochemical and eco-toxicological analyses were combined in a weight of evidence approach to provide environmental risk information for this Ramsar wetland (wetland of national and international importance according to the Ramsar Convention of 1971). Interviews with plantation managers were conducted in order to get an overview over the application of pesticides in the area. Together with the distribution of measured pesticides, an evaluation of potential human risk has been carried out. Toxicity responses of the three bioassays differed to a considerable extent depending on the sample matrices and season. Dry season samples (soil and sediments) resulted in higher mean inhibition of A. globiformis (25%-31%) than rainy season sediment samples (5%). Neither P. xxSummary subcapitata nor V. fischeri showed a significant difference between rainy and dry season samples (water and sediments) even though there was a trend towards higher inhibition during dry season. Growth of P. subcapitata was stimulated (to an average of 69%) by all dry season soil samples while V. fischeri and A. globiformis were inhibited by the same samples at mean values of 34% and 25%, respectively. The observation that toxicities tended to be higher in dry than in rainy season sediment samples in the three bioassays indicate the presence of bioavailable inhibiting contaminants, which are deposited in the banks of streams or rivers when the flow velocity is slow. Low toxicities of rain season samples probably indicate a lower concentration of pesticides/contaminants due to flooding and increased surface runoff. A few dry season sediment samples collected from the outlets streams that receive drains from the rice paddies, as well as those collected adjacent to pesticide mixing /sprayer filling point, showed elevated toxic responses in three bioassays. However, there were no a direct relationship between such samples and the detected pesticides residuals, suggesting that the toxicity was caused by other contaminants. Fuzzy rule based classification of toxicity responses of the three bioassays showed that 73% of samples posed little or no toxic potential risk, while 25% were identified to pose critical risk and only 1% posed elevated critical risk. The algae growth inhibition test showed stimulation in 131 samples out of 143 rainy and dry season samples (sediments, soil and water). Laboratory experiments to evaluate the source of stimulation in the algae test revealed that nutrients such as organic carbon and Vitamin B in the test medium/matrices could stimulate P. subcapitata growth rate. Kilombero samples, however, had relatively low C/N ratios (according to FAO-classification), varying from 10 to 20 for poorly drained soils, suggesting that there is high decomposition of organic matter (enhanced by tropical climatic conditions) and organic humus is transported from the highlands to these lowland flood plain wetlands, thus enriching its organic nutrients. Experiments were carried out to assess whether the blockage of electron transport system by photosystem II inhibitors (specific herbicides) could have caused the stimulation in the P. subcapitata growth inhibition test. It was revealed that: as opposed to chemicals with different mode of action, the presence of PS-II inhibitors in the test medium stimulated the prompt fluorescence (PF) and inhibited the delayed fluorescence (DF), a pattern that is caused by back reactions when the electron transport system is blocked. Although pesticide residuals such as diuron, glyphosate, AMPA, propoxur, atrazine, 2-hydroxy-atrazin, metribuzin, chlorpyrifos, xxiSummary desmethyldiuron, monuron, hexazinone and ametryin were detected in water, sediment and soil samples, the DF and PF patterns were not detected in the environmental samples as they were with single substance tests. Despite the potential to induce fluorescence, the presence of PSII inhibitors in the samples could thus not be responsible for stimulation in the 72-hour growth inhibition test. In conclusion, V. fischeri and A. globiformis bioassays can be used in tropical climates to identify contaminated hotspots. However, the chronic P. subcapitata bioassay could not provide enough information on the toxicity of sample matrices because of the observed stimulations. Thus, there might be a potential to underestimate the toxicity of samples collected from agricultural fields, especially for sediment and soil samples, which are rich in nutrients and are contaminated with low concentration of pesticides. Supplementing the 72-hour algae test with a short bioassay, detecting photosystem II inhibitors, could provide additional, useful information on the toxicity of herbicides in environmental samples. Another supplementary test with the yeast Saccharomyces cerevisiae showed toxic responses in the same magnitude as in the bacterial bioassays when applied to the Kilombero samples. While promising to become a meaningful addition to the biotest battery to indicate fungicides, this test needs optimization due to unexplained reactions when exposed to organic pesticides. The risks of pesticides in the ecosystem depend on the characteristics of a chemical and on the level and pattern of exposure. Unsafe handling of pesticides in the Kilombero valley, which were revealed during field surveys are: pesticide spillage at retail marketing places, spillage during filling up the sprayers, cleaning of the spraying equipment in open waters, on-farm disposal of the pesticide containers and mixing pesticides close to streams, wetlands and ditches. These water bodies surrounding the surveyed plantations have been used by the adjacent households as a source of water for domestic use. Therefore, continued use and unsafe handling of pesticides in these wetlands pose a great risk to human health, wildlife and aquatic organisms. Ecotoxicology using simple, fast and cost effective bioassays, which are novel to Tanzanian setting, might help to provide strategies for reducing the risk from agrochemicals in the Tanzanian wetland ecosystems.
Artemisinin combination therapies price disparity between government and private health sectors and its implication on antimalarial drug consumption pattern in Morogoro Urban District, Tanzania
(BMC Research Notes, 2012) Malisa, Allen Lewis; Kiriba, Deodatus
Universal access to effective treatments is a goal of the Roll Back Malaria Partnership. However, despite official commitments and substantial increases in financing, this objective remains elusive, as development assistance continue to be routed largely through government channels, leaving the much needed highly effective treatments inaccessible or unaffordable to those seeking services in the private sector. To quantify the effect of price disparity between the government and private health systems, this study have audited 92 government and private Drug Selling Units (DSUs) in Morogoro urban district in Tanzania to determine the levels, trend and consumption pattern of antimalarial drugs in the two health systems. A combination of observation, interviews and questionnaire administered to the service providers of the randomly selected DSUs were used to collect data. ALU was the most selling antimalarial drug in the government health system at a subsidized price of 300 TShs (0.18 US$). By contrast, ALU that was available in the private sector (coartem) was being sold at a price of about 10,000 TShs (5.9 US$), the price that was by far unaffordable, prompting people to resort to cheap but failed drugs. As a result, metakelfin (the phased out drug) was the most selling drug in the private health system at a price ranging from 500 to 2,000 TShs (0.29–1.18 US$). In order for the prompt diagnosis and treatment with effective drugs intervention to have big impact on malaria in mostly low socioeconomic malaria-endemic areas of Africa, inequities in affordability and access to effective treatment must be eliminated. For this to be ensued, subsidized drugs should be made available in both government and private health sectors to promote a universal access to effective safe and affordable life saving antimalarial drugs.
Assessing the genetic diversity of five Tanzanian chicken ecotypes using molecular tools
(South African Society for Animal Science, 2013-12-21) Lyimo, Charles Moses; Weigend, Annett; Janßen-Tapken, Ulrike; Msoffe, Peter Lawrence; Simianer, Henner; Weigend, Steffen
The study aimed to evaluate the genetic diversity of Tanzanian chicken populations through phylogenetic relationship, and to trace the history of Tanzanian indigenous chickens. Five ecotypes of Tanzanian local chickens (Ching'wekwe, Kuchi, Morogoro-medium, Pemba and Unguja) from eight regions were studied. Diversity was assessed based on morphological measurements and 29 microsatellite markers recommended by ISAG/FAO advisory group on animal genetic diversity. A principal component analysis (PCA) of morphological measures distinguished individuals most by body sizes and body weight. Morogoro Medium, Pemba and Unguja were grouped together, while Ching'wekwe stood out because of their disproportionate short shanks and ulna bones. Kuchi formed an independent group owing to their comparably long body sizes. Microsatellite analysis revealed three clusters of Tanzanian chicken populations. These clusters encompassed i) Morogoro-medium and Ching'wekwe from Eastern and Central Zones ii) Unguja and Pemba from Zanzibar Islands and iii) Kuchi from Lake Zone regions, which formed an independent cluster. Sequence polymorphism of D-loop region was analysed to disclose the likely maternal origin of Tanzanian chickens. According to reference mtDNA haplotypes, the Tanzanian chickens that were sampled encompass two haplogroups of different genealogical origin. From haplotype network analysis, Tanzanian chickens probably originated on the Indian subcontinent and in Southeast Asia. The majority of Kuchi chickens clustered in a single haplogroup, which was previously found in Shamo game birds sampled from Shikoku Island of Japan in the Kochi Prefecture. Analysis of phenotypic and molecular data, as well as the linguistic similarity of the breed names, suggests a recent introduction of the Kuchi breed to Tanzania.
Assessment of species composition and the genetic population structure of the endemic fishes in the Rufiji River Basin, Tanzania
(Sokoine University of Agriculture, 2024-03) Saiperaki, Jackson Lendoya
The Rufiji River Basin (RRB) is the largest river basin in East Africa and is home to many endemic fish species that are important for local livelihoods and food systems. However, unsustainable fishing practices driven by rapid population growth and high consumer demand have led to a concerning decline in these endemic fishes. In response two protected sites were established including, the Kilombero Valley Floodplain Ramsar site in 2002 and Nyerere national park to protect the endemic fish species from overexploitation. Yet, fish stocks are declining, and it is still unknown whether the implemented measures are consistent with the genetic stock structure of endemic fishes in the basin. Therefore, the aim of this study was to assess the composition of endemic fishes and the genetic stock structure of endemic fish Bagrus orientalis in the RRB. This study used fishers, and the key informant’s interviews, Focus Group Discussion (FGDs), and fishery surveys to assess the composition of endemic fishes. DNA barcoding was also employed to confirm species identities. Tissue samples of 46 different endemic fish species and 182 of B. orientalis were collected from fishers at six landing sites in the RRB including Kivukoni, Mofu, Dinari, Ngalimila, Kidatu, and Zombe and preserved in 99.9% ethanol. Genomic DNA was extracted from each sample using the TIANamp Genomic DNA kit (TIANGEN Biotech, Beijing) and fragments (620 base pairs) of the cytochrome oxidase subunit I gene were amplified. The results showed 33 different fish species, out of which 54.55% are endemic and 45.45% are exotic. Additionally, it was revealed that Heterobranchus longifilis (Mjongwa), Citharinus congicus (Mbala), Labeo congoro (Ningu), Mormyrus longirostris (Sulusulu), and Labeobarbus leleupanus (Mkuyu) are very rare in the catch, despite being classified as Least Concern by IUCN. This suggests that rare species needs reassessment and reclassification by IUCN because their current criteria does not reflect their actual status on the ground. Furthermore, the results revealed significant genetic divergence between the populations of B. orientalis in the RRB (FST = 0.33, p < 0.01). Hierarchical AMOVA revealed that populations in the Ramsar site are genetically connected with those from other sites within the Kilombero Valley Flood Plain (KVFP), but genetically distinct from the populations in Ruaha and Rufiji. This implies that conservation efforts within the Ramsar site might not directly benefit the population in Ruaha and Rufiji. Therefore, it is recommended to establish the protected sites in Ruaha and Rufiji to rescue this population from further decline. The findings also showed that the low genetic diversity among population in Kidatu is due to restricted genetic connectivity, highlighting the need for enhancing habitat connectivity in the area. Moreover, the poor body condition and small sized fish were observed in Kidatu population. This does not conclude overfishing in the area but further studies on population dynamics and fishing pressure should be conducted to understand factors affecting size structure of the fish.
Attitudes and perceived impact of insecticide treated– bed nets on malaria control in rural Tanzania
(Sokoine University of Agriculture, 2019) Alphonce, J.; Maganira, J.; Mwangònde, B. J.
Insecticide-treated nets (ITNs) are the most powerful malaria control tool if used correctly. Yet up to date, utilization is still low. The aim of this study was to investigate the intra-household factors that affect the utilization of ITNs in rural households in MorogoroUrban district. In addition, this study analysed the reasons for ITNs non-use in households with children under five years. Questionnaire, interviews and observation were the key tools for data collection for thestudy. The intra-household factors affecting the utilization of ITNs reported in this study include, chemical substances impregnated in the nets (36%), household financial inadequacy (24%), warmth and discomfort of the nets (24%) and skin irritability (17%), among others. The general community knowledge about mosquito nets was found to be high (91%); however, the knowledge of ITNs was low (30%). In addition, it was found that the ITNs were inadequately accessible in the study community. Based on the results of this study, adequate accessibility of ITNs and community education related to the use and their significance is recommended.
Benthic macroinvertebrate assemblages in mangroves and open intertidal areas on the Dar es Salaam coast, Tanzania
(NISC (Pty) Ltd and Taylor & Francis, 2015) Rumisha, C.; Shukuru, H.; Lyimo, J.; Maganira, Justine Daudi; Nehemia, A.
The assemblages of benthic macroinvertebrates in mangroves and open intertidal areas of the Dar es Salaam coast, Tanzania, was investigated in 2013–2014, revealing 56 species. Higher density, species richness and diversity were recorded in open intertidal areas, compared to nearby mangrove forests. Non-metric multidimensional scaling indicated differences in assemblages between mangrove and open intertidal samples. These differences were confirmed by analysis of similarity. SIMPER identified an average dissimilarity of 97.24% between mangroves and open intertidal samples, most of which were due to the malacostracan Uca annulipes and the gastropod Cerithidea decollata. PRIMER RELATE indicated significant correlation between macroinvertebrate assemblages and the measured physico-chemical parameters salinity, pH, redox potential and sediment particle size, whereas BIOENV and the Monte Carlo permutation test indicated that redox potential, sediment particle size and pH contributed significantly to variation in species composition. Mangroves were dominated by the gastropod C. decollata, and by the malacostracans Neosarmatium africanum and U. annulipes, and open intertidal areas by the bivalves Dosinia hepatica and Eumarcia paupercula. Due to the rich biodiversity in open intertidal ecosystems, it is recommended that conservation efforts along the Tanzanian coast should focus here.
Bioactivity potential of extracts from synadenium glaucescens pax (Euphorbiaceae)
(Sokoine University of Agriculture, 2013) Mabiki, Faith Philemon
The bioactivity of Synadenium glaucescens (Pax) extracts was studied in order to advance the knowledge that would enhance the utilization and commercialization of the plant. Participatory and questionnaire survey methods were used to establish ethnobotanical uses of the plant. Extracts from leaves, roots and stem samples were obtained using cold and hot extraction techniques. Brine shrimp test was involved for cytotoxicity studies. Using an in ovo method, extracts were tested against three viruses of veterinary importance. The agar well diffusion method and minimum inhibitory concentration were used to determine antibacterial and antifungal activity. Soxhlet extraction technique was used for optimization studies and GC-MS and HPLC for phytochemical screening. A total of 220 respondents were interviewed and majorities (94%) were aware of ethnomedical value of S. glaucescens. Twenty six uses were documented. Leaves and roots were the parts mostly used for ethnomedical purposes and grandparents were responsible for knowledge transfer. The cytoxicity test indicated LC50 values less than 30pg/ml for all extracts. More than 50% of the extracts prevented deaths, deformation and formation of pox lesions in embryos challenged with Infectious bursal disease virus and Fowl Pox virus at 0.2 mg/ml, without affecting the host cells. The extracts inhibited multiplication of Newcastle Disease virus at lowest concentration of 0.1 mg/ml. Treatment with ethanolic extracts from the root bark resulted into higher antiviral activity against the three viral particles. Extracts from hot extraction showed higher antibacterial and antifungal activity compared to the extracts from cold extraction. Gram positive bacteria were more sensitive to extracts than the Gram negative bacteria. Streptococcus pyogenes and Candida albicans were the most sensitive bacteria and fungus respectively. Ethanol extracts demonstrated higher antibacterial and antifungal activity than other solvent extracts. Higher extraction yields were obtained within 4 hours of extraction at 30°C for dichloromethane and 75°C for ethanol and particles size of 1 mm. Dichloromethane and ethanolic extracts were composed of triterpenoids and polyphenolic compounds respectively. These findings demonstrate the potential and the feasibility of using 5. glaucescens extracts for treatment of viral, bacterial and fungal diseases. Furthermore, it validates the ethnobotanical uses at community level.
Canonical correlation analysis across vegetation and soil properties of the disturbed and undisturbed coastal forest ecosystems
(Advances in Research, 2019) Ligate, E. J; Chen, C.
This study presents comparative initial information about canonical correlation across forest stand parameters, diversity indices and soil properties in undisturbed forest sites (IFS), agriculture disturbed sites (ADS) and livestock disturbed sites (DGS). Data were collected from Uzigua Forest Reserve in Tanzania. Forty- seven sample plots of 25 m × 25 m were randomly established on IFS, ADS and DGS from which tree inventory data and 141 soil samples were drawn. Data were subjected into Canoco windows 4.5 software for multivariate analyses and comparisons across IFS, ADS and DGS. The correlation of tree stand parameters (TSP) and soil physical properties (SPP) were F=1.207, p=0.242 in IFS, F=2.400, p=0.012 in ADS and F=0.529, p=0.938 in DGS. For soluble bases and TSP were F=2.448, p=0.018 in IFS, F=0.687, p=0.790 in ADS and F=0.743, p=0.808 in DGS. Carbon, nitrogen and potassium (CNP) and TSP were F=0.816, p=0.572 in IFS, F=0.687, p=0.790 in ADS and F=0.070, p=0.020 in DGS. The SPP and Shannon indices had F=1.103,p<0.388 in IFS, F=0.520, p=0.714 in ADS and F=0.932, p=0.444 in DGS. The SPP and Independent Value Index (IVI) were F=0.042, p=0.996 in IFS, F=0.819, p=0.620 in ADS and F=0.633, p=0.724 in DGS. Soluble bases and equitability were F=0.119, p=0.968 in IFS, F=0.001, p=0.001 in ADS and F=0.011, p=0.001 in DGS. The CNP and IVI had F=4.246, p=0.014 in IFS, F=2.729, p=0.018 in ADS and F=2.007, p=0.060 in DGS. The mean higher canonical correlation in the non-disturbed sites indicates that crop-agriculture and livestock grazing affect the interplays between forest vegetation and soil properties. Therefore, human activity disturbs the structure and soil properties.
Carbon stocks potential in regenerating trees of the tropical coastal forest ecosystems
(Book Publisher International, 2020) Ligate, E. J.
Estimation of carbon in the regenerating tropical coastal forest is needed to support conservation and forest monitoring strategies. This chapter presents the determined carbon stocks in regenerating species across forest sites subjected to deforestation because of crop-farming and livestock grazing. The study used thirty-three independent measurements of tree carbon stocks from thirty-three tree families found in the coastal zone of Tanzania. The vegetation was inventoried using a floristic survey of the woody component across intact, crop agriculture and livestock disturbed land-use sites. The biomass was then estimated by employing the existing allometric equations for tropical forests. Thereafter, the above-ground stored carbon was quantified on the sampled tree species found in each land uses. The tree varied (p ≤ .05) in carbon stock across species and land uses. The average carbon (Kg/ha) stored in the regenerated adult trees was 1200 in IFS, 600 in ADS, 400 in LDS. Saplings had 0.43 in LDS, 0.07 in ADS and 0.01 in IFS. Also, seedlings showed an average of 0.41 in IFS, 0.22 in ADS and 0.05 in LDS. It shows that crop-agriculture highly affects the regeneration potential of trees, biomass accumulation and carbon stock than livestock grazing. To restore the carbon storage potential of coastal tropical forests, crop-agriculture must be discouraged, while livestock grazing can be integrated into forest management. Indeed, further studies are required to gauge the integration levels of any anthropogenic activities, so that the natural capacity of coastal tropical forests to regenerate and stock carbon is not comprised further.
A case report of a typhoid fever outbreak with an uncommon vehicle and source of salmonella enterica serotype typhi
(Scientific research and community, 2021-01-19) Mushi, Douglas W.
Two goat caretakers aged 19 and 25 years old were infected with Salmonella enterica serovar typhi (S. typhi); both had eaten raw carrots from a garden enriched with goat faeces in typhoid endemic region of Morogoro, Tanzania. S. typhi strains isolated from garden soils and carrots proved to be from goat faeces. This data provide evidence for the spread of typhoid fever through carrots contaminated by faeces from goats contained transient S. typhi.
Chicken maternal lineage retained long historical relationship between Zanzibar and Oman
(TAJAS, 2021) Lyimo, C.M; Al-Qamashoui, B
The aim of this study is to appreciate the long historical relationship between Zanzibar and Oman, through the investigation of maternal lineage of chickens found in Zanzibar and Oman. Earlier traders and explorer from Arabia, Persian Gulf, West India and China probably visited Zanzibar as earlier as the 1 st Century AD. Oman in Southern Coast of the Arabian Peninsula at the Persian Gulf played a tense relationship between seafaring and commercial people in Indian Ocean. Furthermore, the history of Zanzibar is directly linked to Oman, after Oman Empire expelled and ended the Portuguese dominance of the Indian Ocean trade routes. In 1650 Oman becomes one of the main maritime and mercantile powers in the Persian Gulf and in the Indian Ocean. The sultans of Oman ruled over a substantial part of the Swahili Coast along the Indian Ocean from 1689-1856, controlling elaborate trade routes and cash crop plantations in East Africa. In the mid-1800s, they moved their seat of power from Muscat, Oman, to Stone Town, Zanzibar, and ruled as a constitutional monarchy. This historical relationship can be traced from maternal lineage of chickens that currently exist in Zanzibar and Oman. The mitochondrial genome has been the most widely used system for the investigation of the evolutionary history of species. The high rate of sequence divergence and its uniparental, maternal inheritance can retain evolution relationship as genetic fossils. The Phylogenetic network and Medial-Joining network analysis revealed strong association of evolution relationship between chicken ecotypes from Zanzibar and Oman. The prominent ancestral haplogroups indicated strong association of these chicken populations that were descended from the common ancestry. The Maritime trade interactions and consequences of Oman sultanate regimes in Zanzibar could significantly contributed to the ancestral relationship that existing today between Zanzibar and Oman Chickens.
Comparative analysis of selected factors affecting fruit phenotype and yield of sclerocarya birrea in Tanzania
(Tanzania Journal of Agricultural Sciences, 2014) Andrew, Woiso D.
Knowledge of fruit physical properties and yield is imperative for trees with commercial domestication prospects like Sclerocarya birrea. This study assessed individual fruit weight and diameter as well as yield per tree for the three subspecies of Sclerocarya from two types of land use (farmland and wild). Ten female trees were randomly selected from on-farm and wild sites for each subspecies. From each tree, diameter and weight of 50 randomly selected fruits were measured during a peak fruiting while all fruits per tree were counted and recorded throughout the entire fruiting season for two consecutive years. Results showed that subspecies multifoliolata had significantly heavier fruits and more yield than subspecies birrea and caffra (p < 0.001) Fruits from subspecies birrea were significantly larger than those from the other two subspecies (p < 0.001).Trees from the wild population yielded more fruits that were also heavier that those from on-farm but the difference was only significant for subspecies multifoliolata (p < 0.001) Fruits from on-farm population of subspecies birrea were significantly the largest in diameter (p < 0.001). There was a strong relationship between fruit properties with crown diameter &dbh; and between yield and crown diameter while a decline in rainfall reduced fruit yield across the species and land use. Our results indicate that fruit physical properties and yield have allometric relationship with tree size structure and they vary with rainfall, type of subspecies and probably pollination intensity but not with farmers’ selection pressure and intervention.
Contribution of Tanzania Southern highlands forest diversity to household income and food supplements;The case of Mufindi district in Tanzania
(SCIENCEDOMAIN international, 2017) Msola, D. K; Ligate, E. J.; Chen, C.; Wu, C.
Understanding the role played by forest diversity to supply non-timber forest products for income and food supplements of households is important in forest management and human life. This study was conducted to investigate the role played by non-timber forest products and their implications on income and food supplements in Mufindi District in Tanzania. Methodology: A cross section field survey research methodology was used in this study. Six representative villages in three wards; Rugemba, Igowole and Sadan located within 30 Km to forestreserves were selected. Interviews were conducted to 180 respondents from the three wards. One focus group from each village was conducted while District agricultural officers and village leaders formed a key informant’s category. Quantitative data were analyzed using Statistical Package for Social Science Software and Microsoft excel while memos were produced from qualitative data and used to narrate discussion. Taxonomic plants classification was carried out at Sokoine University of Agriculture botanic laboratory. Results: It was found that non-timber forest products are mostly consumed directly by the people who collect them as a useful dietary supplement, especially when food is scarce. To a lesser extent, they are also sold for cash, but the market for them is badly organized in terms of poor transport and lack of storage facilities, so they are not an important source of income except for people who live near important roads. It was discovered that deforestation and climate change are reducing the potential supply of these products. Conclusions: Given the importance of the sustainable exploitation of non-timber forest products as an incentive for forest conservation, the market for non-timber forest products should be rationalized and expanded. Improvement of the use and role of wild foods should be planned and implemented within a larger scheme of sustainable forest management.
A critical review of policies and legislation protecting Tanzanian wetlands
(Informa UK Limited, trading as Taylor & Francis Group on behalf of the Ecological Society of China., 2018) Materu, Silvia Francis; Urban, Brigitte; Heise, Susanne
Introduction: The benefit of wetlands for reducing poverty depends on the effectiveness of governance systems that influence peoples’ behaviour in the wise use of wetlands. Objectives: This article critically analyses the current poverty reduction strategies, agrarian policies and economic investments governing wetland usage, especially in Tanzania, with regard to their impact on sustainable Ramsar wetlands management. Methodology: It analyses the management structure, domestic policies and legal framework relating to the protection of wetlands in Tanzania in accordance to the wise use concept of the Ramsar Convention. Outcomes: Tanzanian legal provisions for wetland protection are uncoordinated and too limited in their coverage and scope to sufficiently address the destruction of wetland ecosystems. There is no comprehensive national legal framework to guide sustainable management of Ramsar wetlands in Tanzania as laid out by the Ramsar Convention, which the country ratified in the year 2000. Conclusion: Without a sound legislative and policy-making framework, Tanzanian wetlands and their diverse ecosystem services will continue to degenerate with current strategies of increasing agribusiness and other developmental projects or economic investments. This paper provides critical baseline information to inform decision makers to develop appropriate policy and laws, which promote the wise use of wetlands in Tanzania.
Detection of porcine cysticercosis in meat juice samples from infected pigs
(Springer, 2021) Maganira, Justine Daudi; Kidima, Winifrida; Mwita, Chacha John; Höglund, Johan
Background Seroprevalence of porcine cysticercosis has been generally studied using enzyme-linked immunosorbent assays (ELISA) detecting either antigens or antibodies in sera. However, serum is not always readily available. The objective of this study was to assess the diagnostic potential of meat juice in detecting porcine cysticercosis using a cysticercosis antibody ELISA. Methods Sera and meat juice samples from 13 different organs/tissues were collected from nine pigs naturally infected with cysticercosis and from six uninfected pigs reared under hygienic conditions. The sensitivity of the cysticercosis antibody ELISA in detecting porcine cysticercosis in meat juice samples was compared to that in serum samples from the same pigs. Results Using sera, cysticercosis was detected in all nine pigs harbouring cysticerci, but not in those reared under hygienic conditions. The sensitivity of the ELISA was highest in meat juice extracted from the diaphragm (100%), heart (89%) and neck muscle (78%) of the nine infected pigs, whereas it varied between 0 and 44% in the other samples. Conclusion To the best of our knowledge, this is the first study for T. solium cysticercosis serology to use meat juice. Our results show that meat juice from pig carcass organs or muscles is a promising diagnostic specimen for the detection of porcine cysticercosis. More studies including a large sample size of pigs with varying degrees of cysticercosis infection are needed to further prove this concept.
Dhfr and dhps mutations in plasmodium falciparum isolates in Mlandizi, Kibaha, Tanzania: association with clinical outcome
(Tanzania Health Research Bulletin, 2006-05) Kidima, W; Nkwengulila, G.; Premji, Z.; Malisa, A.; Mshinda, H
Sulfadoxine-pyrimethamine (SP), the current first line antimalarial drug in Tanzania, is compromised by evolution and spread of mutations in the parasite's dhfr and dhps genes. In the present study we established the baseline frequencies of Plasmodium falciparum dihydrofolate reductase (pfdhfr) and dihydropteroate synthase (pfdhps) mutant genotypes and their potential for predicting the in vivo efficacy of SP in Mlandizi, Tanzania. The efficacy of SP treatment was by following 116 children with uncomplicated falciparum malaria for 14 days after treatment. Infected blood samples were collected on filter paper at days 0, 3, 7 and 14. Parasite genomic DNA was extracted and point mutations at positions 51, 59, 108 and 164 of the dhfr gene and at 581, 540 and 437 of the dhps gene were analysed by nested Polymerase Chain Reaction/ Restriction Fragment Length Polymorphism. Out of 116 children enrolled, 98 (86%) of eligible children demonstrated an adequate clinical response by day 14. There were 7.3 % early and 6.7% late therapeutic failures. At day 0, only 8.0% (4/50) the parasites showed no mutation at the dhfr locus; for dhps this was 73%. Triple mutant dhfr alleles (Ile 51, Arg 59, Asn 108) occurred in 47%, double mutant dhps (Gly 437, Glu 540) alleles in 7.9%. No mutation was detected at codon 164 of the dhfr gene. The presence of triple dhfr mutant alleles was related to clinical failure, but did not show significant association (Fisher exact test, P=0.166, OR 2.15 0.776.20). The higher rates of mutation on the dhfr do not spell a bright future for SP treatment in Tanzania. It is rational to think of an alternative first line antimalarial drug, while retaining SP for malaria intermittent treatment in pregnancy.
Dietary risk assessment of selected organophosphoris and pyrethoid pesticide residues in fresh harvested tomatoes at Makambako town, Njombe region, Tanzania
(Taylor and Francis, 2022) Bilaro, Jansen S.; Materu, Silvia F.; Temba, Benigni A.
This study aimed to assess the levels of selected pesticides residues in harvested tomatoes and their associated dietary risks to consumers at Makambako Town in Njombe region, Tanzania. Forty-two fresh tomatoes were sampled among tomato farmers during harvesting season and extraction of analytes was done using QuEChERS method and analysed by Gas Chromatography-Mass Spectrometer. Residues of chlorpyrifos, profenofos, gamma cyhalothrin and cypermethrin were alternatingly detected in 78.51% of samples. The average concentrations of residues were 0.014, 0.056, 0.003 and 0.2 mg/kg for chlorpyrifos, profenofos, gamma cyhalothrin and cypermethrin and were all below their respective Codex MRLs. The highest concentration was 0.718 mg/kg for cypermethrin, above the Codex MRL of 0.2 mg/kg. The hazard indexes indicate no potential health hazards to the general population due to the lifetime consumption of fresh tomatoes from the study area. Periodic monitoring of residue levels of pesticides in vegetable fruits, including tomatoes, is recommended.
Dietary strategies to improve feeding practices dietary adequacy and growth of infants and young children in rural Tanzania
(UNIVERSITEIT GENT, 2016) Kulwa, Kissa Buponelo Martin
Undernutrition continues to affect many children below the age of five years in low- and middle income countries. Stunting, also commonly referred as linear growth faltering or retardation, is the most prevalent manifestation of undernutrition compared to wasting and underweight. A global reduction in the prevalence of undernutrition has been reported albeit regional variations. The number of stunted children is increasing steadily in sub-Saharan Africa. The 2010 Tanzania Demographic Health Survey showed unacceptably high levels of stunting, wasting and underweight among children below the age of five years; 42.0%, 4.8% and 15.8%, respectively. Children below the age of three years, children in rural areas and those living in the southern and central regions of the country were the most affected. Consequences of undernutrition during the formative years include poor growth, increased risk of and prolonged morbidity, mortality, delayed cognitive and motor development. Promotion of optimal feeding, health and growth during the first two years of life is a matter of immediate concern. Interventions to improve feeding and nutrition of infants during this period include promotion of breastfeeding, communication and education on complementary feeding behaviours, provision of food supplements, single and multiple micronutrients supplementation, reduction of diseases through appropriate hygiene practices, management and treatment of severe acute malnutrition. Reviews of previous interventions have reported that interventions with an educational component can effectively improve complementary feeding behaviours, dietary intake and child growth. There is limited information on the implementation and evaluation of evidence- and theory-based, culturally appropriate nutrition education interventions to improve diets and growth of rural infants in Tanzania. The aim of this thesis was to: 1) characterise dietary and growth patterns of infants and young children living in rural Tanzania, and 2) develop and evaluate the effectiveness of a nutrition education package on feeding practices, dietary adequacy and growth of infants and young children in rural Tanzania. It was hypothesised that the nutrition education package would improve feeding practices, dietary adequacy and growth as compared to the routine health education given at health facilities. To accomplish these objectives, the research was organised into two studies: two cross-sectional studies to establish the nutrition- and health-related problems in a rural area and guide decisions on improvement, and an intervention study to improve dietary practices and growth. A cross-sectional survey involving 496 infants (age 1-12 months) was conducted in six villages of Mpwapwa district in 2009 (Chapter 2). The study assessed feeding practices and nutritional status of children, and determined the macronutrient and selected micronutrient contents in commonly consumed complementary meals. Implications for dietary adequacy and nutritional status of the studied children are reported. The same cohort of infants (n=374, age 9-20 months) was revisited in 2010 to evaluate progress in their nutritional status after the first survey. Results of the 2009 survey showed that mean age of introduction of complementary foods (3.30±1.45) was earlier than the recommended age of six months. Porridge was the main complementary meal and the porridge samples contained relatively high water content, increasing the likelihood of reduced nutrient content. Mean number of meals consumed including snacks were lower than the age specific World Health Organization recommendations. There was limited inclusion of nutrient dense foods (e.g. legumes, animal-source foods, vegetables) in the meals. Small meal portion sizes, limited variety and the generally low nutrient content of meals increased the risk of not meeting the recommended nutrients intakes. Prevalence of stunting in 2009 and 2010 was 33.5% and 59.3%, respectively. Morbidity due to acute respiratory illness (ARI) was 63.9% in 2009 and 56.4% in 2010. Diarrhoea affected 48.4% children in 2009 and 36.4% in 2010 Overall prevalence of anaemia was 36.1% in 2009 and 36.7% in 2010. Results of the cross-sectional surveys demonstrated a need for a nutrition intervention to improve dietary practices, health and growth in infants and young children in rural Tanzania. While interventions to improve feeding, health and growth exist, it is imperative that they are contextualised to enhance feasibility and sustainability. Intervention Mapping and Theory of Planned Behaviour provided systematic frameworks for the design, development and evaluation of a nutrition education package (Chapter 3). The package had three components: 1) education, counselling and cooking demonstration with mothers, 2) training of village health workers (VHW) to counsel mothers and family members during monthly home visits, and 3) supervision of the trained village health workers. Training and education materials were also developed for respective participants. A cluster randomised controlled trial was implemented for six months in Mpwapwa district to evaluate the effectiveness of the package. Eighteen villages were randomly allocated to either routine health education (control, n=9) or nutrition education package (intervention, n=9). Routine health education is a standard government health service for children below the age of five years, offered monthly by health staff at health facilities. It offers education to mothers during growth monitoring and immunisation contacts. The sessions are usually short (10-15 minutes) and focus on general health issues including child feeding, prevention of diseases such as malaria and importance of immunisations. Primary outcome was length-for-age Z-scores. Secondary outcomes included weight, weight-for length Z-scores, intakes of energy, fat, iron and zinc from complementary foods, meal frequency and dietary diversity. A process evaluation was also carried out to provide insights into the nature of the processes leading to intervention effectiveness or ineffectiveness. A total of 370 infants aged 6-7 months (control: n=186; intervention: n=184) participated in the intervention trial starting December 2014. Findings of the trial are presented in Chapter 4. At baseline, inadequate feeding practices and nutrient intake, morbidity, anaemia and poor growth were widespread. After intervention, mean change in feeding frequency was modestly higher in the intervention than control group (1.63 vs. 1.27, p=0.051). Mean change in dietary diversity was significantly higher in intervention than control group (2.03 vs. 1 50, p=0.005). Infants in the intervention group had higher intakes of energy (+43.8 kcal, p=0.019) and fat (+2.7g, p=0.033) than infants in the control group. No effect was observed for iron and zinc intakes. The intervention resulted in significant mean change in length (0 47cm, 95% Cl: 0.01, 0.92, p=0.043) and length-for-age Z-scores (0.20 Z-score, 95% Cl: 0.29, 0.38, p=O.O22) in intervention compared with the control group. The intervention had no differential effects on mean changes in weight, weight-for-length and weight-for age Z-scores. Chapter 5 presents results of the process evaluation. Fidelity, recruitment, reach, dose and contextual factors were reported for each package component. The package components and elements (training VHW, education and cooking demonstration with mothers, home visits, supervision of VHW) were implemented across the intervention villages as planned. The intervention was well received with good dose and was well accepted by VHW, mothers and their families. VHW knowledge on IYCF increased significantly during the two training sessions (I'1 session: +5.7-point, p<0.001; 2nd session: +4.1-point, p=0.003). Between midtrial and end of trial, the majority of mothers tried the promoted recipes at home (89.8% and 94.6%) and some tried all the recommended feeding and health practices (37.7% and 66.1%) Barriers to adoption of the recommended practices included high maternal workload, cultural beliefs on feeding choices and inadequate household income. Chapter 6 discusses the implications of the findings and recommendations for further research. In conclusion, this PhD research demonstrated that inadequate dietary practices and poor nutrition are consistently widespread in infants and young children in rural settings. Further, the nutrition education package adds to the evidence that practical nutrition education incorporating cooking demonstrations and regular home visits can improve feeding practices, dietary intake of macronutrients and growth, better than the routine health education delivered at health facilities. Child health status, socio-cultural and household factors played a significance role in influencing intervention outcomes. Barriers to intervention effects included high infant morbidity, high maternal workload, inadequate household income and mothers' habitual and cultural influences on feeding choices. The research calls for a review of routine health education for the delivery of quality nutrition services and improvement of child health services for reducing morbidity burden. There is also a need for joint strategies with other sectors (e.g. agriculture-livestock production, marketing-roads infrastructure, income generation initiatives) to address the underlying causes of child undernutrition.

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