Theses and Dissertations Collection

Permanent URI for this collectionhttp://10.10.97.169:4000/handle/123456789/54

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Estimation of carbon stocks in Uchindile forest plantation, Kjlombero District, Tanzania
(Sokoine University of Agriculture, 2009) Wesaka, Ronald Makongoro
The study reported here was conducted to estimate carbon stocks in Uchindile forest plantation, Kilombero district, Tanzania. The tested hypothesis was Pinus patula and Eucalyptus saligna plantations had similar carbon sequestration. Data was collected from two main plantation species i.e. Pinus patula and Eucalyptus saligna. Stratified random sampling design was adopted. Three sample plots measuring 20 m x 20 m were established in each stand. Diameter at breast height (DBH) and height were measured for stand data estimation, especially volume. Top soil samples 0-15 cm and 15-30 cm depths were sampled. Then, total biomass and soil carbon stored in the plantation was prepared using Microsoft Excel. The CO2FIX was used to estimate biomass and soil carbon in the two plantations. Lundgren equations were used to estimate biomass in the pine plantations. For each species, stand ages selected were 4, 6, 8, and 10 years. Field data results indicated that at year 4, 6, 8, and 10 Pinus patula plantations sequestered stand biomass C of 7.48, 21.34, 42.22 and 61.48 Mg Cha1. Eucalyptus saligna plantations sequestered stand biomass C of 43.5, 137.53 and 183.71 Mg Cha’1. Pinus patula plantation had mean soil C of 81.29, 80.03, 76.76 and 76.47 Mg Cha'1 at year 4, 6, 8, and 10, respectively. Eucalyptus saligna plantation had mean soil C of 73.65, 86.06 and 77.77 Mg Cha’1 at year 6, 8 and 10. The two plantations sequestered total C of 218.18, 342.04 and 399.43 Mg Cha’1 at year 6, 8 and 10, respectively. This translates to 800.72, 1255.29 and 1465.91 Mg COjha’1, at the respective ages. Mg COzha’1 = Mg Cha’1 multiplied by 3.67. The T test indicated a very significant (P<0.05) difference in carbon sequestration between the two plantation species. Eucalyptus plantations sequestered 1.15 to 1.89 times more carbon in comparison to the pine.
Germination studies on seeds of trichilia emetica and vangueria infausta
(Sokoine University of Agriculture, 1998) Msanga, Heriel Petro
The effect of various physical seed coat scarifications and chemical treatments were studied to determine presowing prescriptions that would ensure uniform, fast and high germination in seeds of Trichi Iia emetica and Vangueria infausta. The studies involved eight 3x5 factorial model experiments arranged in a randomized block design with with 4 blocks each. For each of the two species, two different experiments were conducted in the laboratory and repeated in the nursery. The first experiment of Tri chi Iia erne t i ca involved 3 types of physical seed coat scarification and soaking the seeds in gibberellic acid (CA3) at 5 concentrations; i.e. 0, 250, 500, 750, and 1000 ppm. A second experiment involved 3 types of physical seed coat scarification and soaking the seeds in potassiun nitrate (KNO^) at 5 concentrations; i .e. 0.0, 0.2, 0.4,0.6 and 0.8%. The first study involving Vangueria infausta included 3 types of physical seed coat scarification and treatments of the seed with 5 concentration levels of hydrogen peroxide (H202); i .e. 0, 2, 4, 6 and 8%. In the second experiment, 3 types of physical seed coat scarifi- cation and soaking the seeds in 5 concentration levels of indole acetic acid (IAA); i.e. 0, 25, 50, 75 and 100 ppm were studied. Unscarified seeds of Trichi Iia emetica (without chemical treatment) atta ined cumulative germination of 29% and 35%, while seeds with complete removal of both the aril and the seed coat attained cunulative germination of 94s and 93« in the laboratory and nursery experiments respectively.
Exploitation of brachylaena liuilleiisis (silver oak) and its implication to regeneration of woody plants in Bombo west forest reserve, Korogwe, Tanzania
(Sokoine University of Agriculture, 2009) Mumwi, Damas Mkonda
This study was carried out in Bombo West Forest Reserve, Korogwe District, Tanzania to assess the extent of human exploitation of Brachylaena huillensis and its implication to regeneration of woody plants. Forest vegetation was stratified into highly, mild and least disturbed areas. Data were collected using forest inventory, questionnaire survey, discussion with key informants and participant observation. The overall average tree density of woody plants was 433 stems ha'1 while wood volume and basal area was 36.869 m3 ha'1 and 5.4 m2 ha'1 respectively. Overall average tree density of B. huillensis was 47 stems ha'1, basal area (1.813 m2 ha'1) and volume (14.068 in3 ha'1). It was observed that Brachylaena huillensis is abundant, dominant and frequently occurring in the forest reserve with Importance Value Index of 0.470 compared to the next important species Scorodophlaeus ficheri (0.545). Brachylaena huillensis was found to be heavily exploited indicating 82 stem ha'1, 2.622 m2 ha'1 and 16.376 m3 ha'1 while density distribution by dbh size classes indicated abnormal trend, which signifies poor recruitment and regeneration failure. The overall average of Brachylaena huillensis regenerants was 5076 seedlings ha'1 compared to 15 646 seedlings ha'1 of all woody plants in the forest reserve. Brachylaena huillensis is known by 95.7 % of the respondents whereby 79.7% of the respondents used the species for firewood. The species is intensively utilized as pole for buildings as mentioned by 42 % of the respondents and its poles were claimed to be durable and extremely resistant to termites. Carvings, charcoal, bush fire, trees and poles cutting are main threats of the forest reserve and B. huillensis in particular. Moreover, it was also observed in this study that the wood harvesting mainly for carvings and charcoal is an indication that B. huillensis and the forest in general are currently threatened and needs effective management strategies to control the illegal activities. It suggests that the domestication of the species on farmlands could probably reduce the pressure to the species and the forest in general.
Pollination biology of coffea kihansiensis (rubiaceae), an endemic wild coffee species in kihansi gorge forest, Tanzania
(Sokoine University of Agriculture, 2018) Bugingo, Adili
The Kihansi wild coffee. Coffea kihansiensis. is an endemic coffee species found in the understory of the Kihansi gorge forest in Tanzania. In this study, pollination biology of C. kihansiensis was assessed. The aim of the study was to understand the relationship between the flower biology of C. kihansiensis and its insect pollinators. Specifically, the study investigated flowering patterns, floral dimensions, insect visitors, pollinators, floral rewards and breeding system. A systematic sampling design was employed and three C. kihansiensis populations were used as sampling blocks. Data were collected through direct observations. direct counts, measurements and experiments. Flowering in the species exhibited a bing-bang (mast) flowering pattern and was observed to occur from mid-December through to January following short rains. C. kihansiensis flowers were visited by a wide range of insects belonging to 44 species. Bees of various species were the most abundant insect visitors on the flowers and appeared to be the most effective pollinators of C. kihansiensis. Flowers typically offer pollen and nectar to insect visitors. Insect visitors* frequencies were higher in the morning than in the afternoon and evening, and were associated with the timing of pollen and nectar release. Irrespective of species, insect visitation was higher in morning, at 1100 hr. Fruit set was high in cross pollinated flowers. The low fruit set in the absence of pollinators might be interpreted as an adaptation to low pollinator visitation rate or pollen limitation. The self-incompatibility index (1SI) was estimated to be 0.72. Results from hand-pollination and the ISI value show that C. kihansiensis is partially self-incompatible, able to reproduce through both selfing and outcrossing. It showed that pollinators play important role in enhancing the productivity of C. kihansiensis. The above findings imply that in situ conservation of C. kihansiensis must focus on monitoring the species, its insect pollinators and conservation and management of its natural habitat.
Deadwood carbon stock and stand structure characteristics in different vegetation types in Tanzania
(Sokoine University of Agriculture, 2023) Masanja, Sarafina N.
Deadwood is an important element playing an essential role in the maintenance of biodiversity, soil fertility and carbon sequestration. The amount of carbon stored in standing dead trees and other fallen woody debris alive or dead forms an important component of the carbon pools. Previous studies have estimated total carbon stocks for different land cover classes but they did not segregate deadwood in estimating carbon and none had considered levels of uncertainty estimates and the state of the woody decay. Also, there are limited information on stand structure of deadwood and how it is related to deadwood biomass. This study aimed to quantify deadwood carbon stocks in different vegetation types, the relationship between deadwood species structural diversity and deadwood carbon stock along different environmental variables. The study used dataset from National Forestry Resources Monitoring and Assessment of Tanzania (NAFORMA). The study revealed that solid deadwoods had higher carbon stocks and emission factor than rotten deadwoods whereby the estimated deadwood carbon stock ranges from 0.11 to 1.01 tC ha -1 , contributing 0.79% of the total carbon from different vegetation types. Compared to other vegetation types, forests and woodlands had higher deadwood carbon stocks and emission factor while grasslands had the lowest. Species abundance and soil moisture were positively significant related to deadwood carbon, with the highest effect shown by soil moisture while species richness and soil organic carbon had a negative significant relationship with deadwood carbon. In lowland forest, deadwood carbon stock of Brachystegia sp.-Pterocarpus angolensis (BP) community was positively significant influenced by soil moisture while in woodlands, deadwood carbon stock for Julbernardia globiflora-Pterocarpus angolensis (JP) community was negatively significant influenced by soil organic carbon and deadwood carbon stock of Dalbergia melanoxylon-Pteleopsis myrtifolia (DP) community was positively significant influenced by soil moisture. Understanding how deadwood carbon and stand structure of deadwood interact with environmental conditions contributes to the understanding of forests and woodlands carbon dynamics. Therefore, this study provides valuable insights for policymaking related to climate change mitigation, carbon accounting and effective biodiversity conservation in tropical ecosystems
Above ground biomass, land cover change and regeneration of tree species under different grazing intensities in miombo woodlands,Tanzania
(Sokoine University of Agriculture, 2024) Rugambwa, Thadei Tarcis
Tanzania's livestock sector faces challenges due to overgrazing, threatening the ecological balance of critical habitats like Miombo woodlands. This study investigates the impact of grazing pressure on land cover changes, tree biomass, and regeneration potential in these woodlands of Kilosa, Kilombero, and Handeni districts. Despite existing research on the damaging effects of overgrazing, a comprehensive analysis specific to Tanzanian Miombo woodlands is lacking. We address this gap by analyzing high-resolution satellite imagery (Landsat 5 TM & 8 OLI) from 1995 to 2021 to quantify land cover changes across the study areas. Field surveys were conducted to assess grazing intensity, aboveground biomass (AGB), and tree regeneration within representative Miombo woodland sites. Allometric models estimated tree-level AGB, which was then scaled to calculate plot-level AGB (tonnes/ha). Statistical analyses explored relationships between grazing intensity and land cover change, biomass dynamics, and tree regeneration. Results reveal a negative impact of medium and high grazing intensities on AGB compared to light grazing. Satellite image analysis indicates higher tree cover loss under medium grazing (63.5%) compared to high (61.5%) and light grazing (23.2%) between 1995 and 2022. Additionally, grazing intensity significantly affects tree regeneration (number, species richness, diversity, and evenness) (p < 0.05). These findings show the damaging effects of overgrazing on Tanzanian Miombo woodlands. This knowledge can inform sustainable grazing practices, collaborative management strategies, and efforts to mitigate forest cover loss. Further research could explore optimal grazing levels and develop specific recommendations for policymakers and land managers.
Effects of spacing on growth,yield and wood properties of Tectona grandis at Longuza forest plantation, Tanzania
(Sokoine University of Agriculture, 2024) Samamba, Enos.
In forest management, understanding the influence of spacing on tree growth is crucial, as it goes hand in hand with stand growth as well as yield at the final harvest. Also, spacing, especially narrow spacing, has been used to control the stem quality of trees, as it influences the stem straightness as well as the branching behaviour. On the other hand, tree growth, particularly radial growth, means an increase in wood materials such as cell wall substances, latewood, and earlywood. Those wood materials influence the physical and mechanical properties of wood. Behind those influences, an understanding of the influence of spacing on the final harvest is required to decide on appropriate spacing to economize the value of the final harvest. However, information on the spacing influence on growth, yield, and wood properties of Tectona grandis at an older age in Tanzania is limited. Thus, this study is intended to evaluate the influence of spacing on the growth, yield, and wood properties of 24-year-old Tectona grandis at Longuza Forest plantation, Tanzania. Data were collected from a spacing trial with a randomized complete block design with three treatments, namely 2 x 2 m, 3 x 3 m, and 4 x 4 m, replicated three times. For growth and stem quality, all trees' diameter at breast height (dbh), height, and stem quality were evaluated. Then, dbh data were used to obtain basal area (Ba), volume, and the mean annual increment (MAI). Furthermore, three trees from each spacing were sampled for physical and mechanical properties. The basic density (BD) was determined using over-dry weight and green volume, while the heartwood (HW) percentage was calculated using the cross-sectional area of the HW and disk underbark. Moreover, all mechanical properties were tested using a Monsanto tensiometer machine. An analysis of variance (ANOVA) was used to evaluate the influence of spacing. Then, Tukey’s Honest Significant Difference test (p = 0.05) was used for multiple comparisons of means. Results revealed that at the older age of 24 years, spacing did not statistically influence all growth and yield parameters studied. A 4 x 4 m spacing produced trees with higher dbh and height, while higher Ba, volume, and MAI values were observed at 3 x 3 m. Stem quality was statistically different in some spacings, where only 2 x 2 m differed statistically from 4 x 4 m. All physical and mechanical properties evaluated were not statistically influenced by spacing except CLST to grain, whereby the spacings of 2 x 2 m and 3 x 3 m had significantly higher values than a spacing of 4 x 4 m. In conclusion, results showed that despite the growth and yield parameters not being statistically influenced by spacing, a spacing of 3 x 3 m could ensure a higher yield compared to other spacings. Also, it produces trees with high stem quality, similar to closer spacing, without affecting both physical and mechanical properties. This is because the values of those properties appear to have slight differences among the spacings. Keywords: Tectona grandis, Spacing, Volume, Stem quality, Basic density, Heartwood percentage
Survival, growth and wood properties of eucalyptus urophylla provenances in southern highlands, Tanzania
(Sokoine University of Agriculture, 2024-05) Sangiwa, Milkajane Job
In Tanzania, commercial forestry is a developing industry that plays a key role in many important development areas, such as construction and rural electrification, it‟s also one of the strategies required to reduce the loss of natural forests and mitigating the increasing shortage of wood supply. Eucalyptus urophylla has been preferred as important forest plantation species for wood production and it‟s among the most common Eucalyptus species planted in Tanzania for commercial purposes. However, there is lack of reliable sources and diversity of the materials in the country. Tree improvement activities, like provenance testing, are essential to ensuring high-quality timber trees by identifying the best sources of a species for a given area in order to increase survival and productivity. This information is required to assist in formulating the efficient operation of a breeding programme through which the quality and productivity of plantations may be improved. The use of important economic traits during selection of the best provenances has the potential to provide valuable inputs for commercial forestry industry and conservation of breeding materials. This study aimed at evaluating the variation within the species and to determine the best seed sources for planting in the Southern Highlands of Tanzania. Specifically, the study tested the variation found in the established trial for certain economically important traits such as survival, growth, wood basic density and stem quality. From this, the study aimed to determine provenance differences between these traits. This information will be used as basis for selection of best performing provenances for future plantation establishment and genetic conservation efforts. The study‟s results showed significant differences (p > 0.05) in survival, DBH, Ht, Vol, BA, and MAI, the average values for these parameters were 90.6 %, 22.54 cm, 30.7 m, 264.85 m3ha-1, 7.61 m2ha-1, and 19.16 m3ha-1yr-1 respectively. The study identified superior-performing provenances, including provenance 40, 59, 60, 61 and 62, where majority originating from Wetar island. Furthermore, the results revealed significant variation in stem straightness among provenances with the average score of 5.0. Provenances 40, 60 and 59 had trees with superior straightness. In addition, substantial variations in BD were observed among the provenances. The average basic density was 548.31 kg/m3, with mean ranging 509.24 kg/m3 to 586.31 kg/m3. Based on the findings the study recommends planting provenances 40, 59, 60, 61 and 62 in large scale at Southern highlands of Tanzania and in areas with similar climate and soil conditions. The methodology and findings of this study can be used as a basis for developing and selecting superior provenances and progenies to improve productivity, for plantation establishment and sustainable utilization of its wood resources. Future studies and breeding efforts should be done on other important traits such as pulp yield, drought tolerance and resistance to pests and diseases. Additionally, this trial can be used for conservation of forest genetic resources by preserving the genetic diversity of the species in the country.
Infestation density and habitat suitability of tree girdling beetle, paranaleptes reticulata Thoms. (Coleoptera: Cerambycidae) in Eastern Tanzania
(Sokoine University of Agriculture, 2024-05) Nilahi, Medison Fildeline
Despite the increased rate of spread and infestation of the insect pest, Paranaleptes Reticulata Thoms among government plantations and other tree growers in Eastern Tanzania, there is limited information on the infestation patterns and suitable habitat distribution for P. reticulata. To provide this piece of information this study aimed at assessing first, infestation density and severity of P. reticulata across government plantation forests and community woodlots. Modelling the current and potential future habitat distributions of the P. reticulata in Eastern Tanzania. Data on presence of P. reticulata and number of trees infested by P. reticulata were collected from 158 plots to count and measure trees infested by P. reticulata. Also, age, diameter of infested trees and the occurrence coordinates were recorded. Non-parametric Kruskal-Wallis test was used to analyse if infestation density and severity differed between agroecological zones and species. Dunn's post hoc test was used to assess which sites and species differed from each other in terms of infestation densities and severity. Generalised linear mixed models (GLMMs) with a negative binomial error distribution and plots as a random factor was used to to assess the direction of associations between environmental variables and the infestation density and severity of species. Ensemble species distribution models combining presence records for P. reticulata and potential environmental variables was used estimated habitat suitability. Results on infestation patterns revealed that infestation density (H = 83.95, df = 3, p < 0.001) and severity (H = 50.62, df = 3, p < 0.001) differed between sites. Similarly, infestation density (H = 29.63, df = 2, p < 0.001) and severity (H = 29.63, df = 2, p < 0.001) differed between species. GLMMs indicated that tree diameter, tree age, and solar radiation were negatively associated with both infestation density and severity, while wind was positively associated with both infestation density and severity. Infestation density and extent of severity were significantly higher for Corymbia citriodora and Eucalyptus tereticornis compared to the reference species Commiphora Africana. Results on habitat suitability indicated that the highly suitable habitat for P. reticulata would decrease significantly in the year 2050 and 2090 under SSP126 and SSP585 scenarios. The study concludes that exotic species are more prone to P. reticulata infestations across sites compared to native species and climatic variables play crucial in determining current and future habitat suitability for P. reticulata. The study recommends age-, size-, and species-specific preventive measures to reduce P. reticulata infestation density and severity in Tanzania. Predictive maps could also be used by managers, planners, and tree growers to strategize, plan and making informed decision about the current and future infestations status.
Pollination efficiency of apis mellifera and hypotrigona gribodoi on capsicum annuum fruit set and yield in Morogoro region, Tanzania
(Sokoine University of Agriculture, 2024-05) Mbazi, Paschal Hotay
Pollination by insects accounts for over 70% of global food crops production. Among insect species, bees are one of the most efficient pollinators though their pollination efficiency varies between species. Amidst rising worries about declining pollinator populations due to human activities and changes in climate, comprehending diverse pollinator capabilities is crucial for conservation. While stingless bees show promise as commercial pollinators, their capacities compared to Apis mellifera remain insufficiently understood, resulting in limited domestication and thus threatening their population.. This study evaluated the pollination efficiency of Apis mellifera and Hypotrigona gribodoi on yield and fruit set in Capsicum annuum. A randomized complete block design experiment was conducted with three replications and three caged treatmentswhich are Apis mellifera, Hypotrigona gribodoi, and self-pollinated plants. Each treatment was replicated three times to assess the effects of pollination on yield and fruit set rates. We made comparison on bees' foraging activities and computed their impact on fruit set. Furthermore, we explored the influence of abiotic factors on bees foraging activities, to a comprehensive analysis of the intricate relationship between pollination, bee behavior, and environmental factors. Analysis of variance (ANOVA) was used to compare the differences in fruit quality, seed quality, and fruit set rate between the two species. Kruskal wallis was used to test for difference among data which are not normally distributed. Tukey's Honestly Significant Difference (HSD) and Dunn tests were used for normally distributed and non-normally distributed data respectively. To compare the difference in bee foraging activity, we use the Wilcoxon rank-sum test. We employed a Generalized Linear Model (GLM) to investigate the relationship between fruit set rate and foraging activity, and a Poisson Regression Model to explore the relationship between foraging activity, abiotic factors, and bee species. The results show that the number of fruits per plant, fruit transverse circumference, fruit vertical circumference, fruit weight, and percentage fruit set rate per plant were higher in the plot pollinated with Hypotrigona gribodoi, followed by Apis mellifera, and lastly the control plot and the difference was statistically significant (P < 0.05). However, there was no significant difference in the number of seeds per fruit and the weight of 100 dry seeds per fruit among the two species (P>0.05). Hypotrigona gribodoi showed higher flower visits, pollen-carrying workers, and visitors per flower than Apis mellifera, with significant differences (P < 0.001). Conversely, Apis mellifera had more exiting workers (P < 0.001). Moreover no difference in time spent on the flower (P>0.05). Also the number of workers entering with pollen (P<0.001), workers exiting the hive (P<0.001), and time spent on the flower (P<0.05) have a significant effect on the fruit set rate of Capsicum annuum. The number of visitors per flower and the number of flowers visited do not have a significant effect (P>0.05). Temperature and humidity significantly affect the number of visitors per flower, the time spent on flower and the number of workers exiting the hives. However, the number of flowers visited and the number of workers entering the hive with pollen were not influenced by temperature and humidity. These findings suggest that Hypotrigona gribodoi is a more efficient pollinator of Capsicum annuum L. Furthermore, the foraging behavior of Apis mellifera and Hypotrigona gribodoi is affected by temperature and humidity affecting the fruit set rate of Capsicum annuum. More research on the differential pollination efficiency among different bee species in crop production is imperative.
Characteristics of bee fodder plants of mlele beekeeping zone, Katavi, Tanzania
(Sokoine University of Agriculture, 2024-05) Kipangula, Dorothea Clemence
Pollination by insects, particularly bees, is essential for biodiversity conservation and plant reproductive success. Tanzania is characterized by a rich diversity of flowering plants estimated to be over 9000 species. A wide variety of flowering plant species serve as bee fodders and are essential to maintaining healthy bee populations. Mlele District in Katavi region of Tanzania is among the highest honey producing area in the region. Several studies on bee fodder plants characteristics, including their composition and nectar quality have been done in temperate and sub temperate regions with few in the tropics. These studies have reported the impact of environmental and human disturbances on bee fodder plants. Despite the potential of Katavi region for beekeeping, few studies have been done in the region, especially on the characteristics of bee fodder plants incorporating environmental, disturbance and the nectar quality. This knowledge gap results into ineffective conservation of food sources for bees, unsustainable beekeeping practices, low production and quality of bee products. The study overall objective was to determine the characteristics of bee fodder plants of Mlele Beekeeping zone. The study included two objectives, the first objective was to determine the composition of bee fodder plants along environmental and disturbance gradients and the second was to determine the periodicity of floral rewards by the bee fodder plant species. A systematic sampling design was employed to assess how environmental and disturbance gradients impact bee fodder plants composition. A total of 50 rectangular plots of size 50 by 30 m were laid in two transects with 25 plots in each transect. Plant flowers were observed for 10 minutes and were scored as bee fodder plants after at least three bees visited the flower within the observation period. The periodicity of floral rewards objective employed purposive sampling design on the basis of provision of measurable amounts of nectar and enough flowers to conduct the study with repeated measurements. Plants in which the honeybees extended their proboscis into the flowers were determined as nectar rewarding plants and where bees collected pollen were determined as pollen rewarding plants. Data collection on bee fodder plants composition was obtained through a summary of species data list and their abundance values. Climatic data was obtained from the current climate data set downloaded from world climate site with a 30 arc seconds resolution and four subsets of biophysical data were used. Disturbance data was recorded for presence or absence and the disturbance type.550 hours of observation were made for recording of flower visitors on ten bee fodder plant species from 0700 hours to 1800 hours. Nectar was extracted by micro capillary tubes and quality was measured in form of total sugar concentration by the use of a digital handheld refractometer. In the data analysis section, data skewness was addressed by standardization of the data. Detrended Correspondence Analysis (DCA) was applied to assess the ecological gradient's magnitude within the species composition matrix and to determine the appropriate constrained ordination method. The results gave the option for Canonical Correspondence Analysis (CCA) due to the data's heterogeneity. Log-transformations were applied to species abundance data to meet multivariate normality assumptions. Rare species occurring in fewer than five plots were excluded from the analysis. Stepwise automatic forward selection identified significant explanatory variables for CCA. The chosen variables were then constrained against tree species and community composition. Permutational Multivariate Analysis of Variance Using Distance Matrices (Adonis) was employed for variance partitioning. The community composition was identified by the use of Bray-Curtis’s dissimilarity and Silhouette validation. Generalized linear models were created to examine visitations and effect of nectar concentration and temperature on bee visitation rate. Overall, 71 bee fodder plants belonging to 25 families were recorded. The results revealed that 23% of the variation in the composition of dominant tree species within the study area could be attributed to the interplay of environmental and disturbance factors. Elevation emerged as the most influential predictor, accounting for approximately 11.6% of the total variation. Annual mean temperature contributed around 3.5% to the observed variation and annual precipitation about 3.6%. Four bee fodder plant communities were identified in the area with first cluster being dominated by Erythrophleum africanum, second with Brachystegia glaucescens, third with Diplorhynchus condylocarpon and fourth Bobgunnia madagascariensis. Nectar concentration was identified as a central driver of bee visitation patterns. The bee fodder plants including Antidesma membranaceum and Friesodielsia obovata, showcased nectar concentration percentages that significantly enhanced their attractiveness to bees. The results of this research study have the potential in providing valuable insights to beekeepers and conservationists for improving beekeeping practices in Mlele Beekeeping zone. It provides understanding into factors influencing bee visitation rates to different bee fodder plant species. It also highlights the significance of nectar sugar concentration and temperature in shaping bee foraging behavior. Environmental factors particularly elevation, annual mean temperature and annual precipitation are seen to be important in shaping the composition of bee fodder plants. The findings recommend prioritizing and promoting planting and conserving bee plant species with high visitation rates such as Antidesma membranaceum, Psorospermum febrifugum and Securidaca longepedunculata to support bee populations and enhance pollination services. Further research is needed into other bee fodder plants traits that attract bee to deepen our understanding of bee interactions. Understanding the relationship between environmental factors and bee plant communities in other locations and other factors such as soil type and land use should be considered. As ecosystems face ongoing challenges from climate change and human activities, such research becomes increasingly valuable in ensuring the health of bee populations and the preservation of biodiversity. Further research in other regions and at different scales is needed to expand our knowledge of these vital relationships and their implications for beekeeping and conservation efforts globally.
Butterfly species diversity across ecological gradients in mpanga kipengere game reserve and surrounding farmlands, Tanzania
(Sokoine University of Agriculture, 2024-05) Kasisi, Privatus Maximillian
Butterflies are a species that are particularly sensitive to environmental changes. Identifying indicator species is crucial for assessing ecosystem health and ecological monitoring. Maintaining natural habitats is crucial for preserving insects and other species that indicate environmental changes. However, the Mpanga/Kipengere Game Reserve and its surrounding farmlands are facing disturbance due to human activities, putting many wildlife species, particularly larger mammals, at risk. To determine the impact of human activities on butterfly species diversity and abundance in the reserve and its surrounding areas, we conducted a study from November 2021 to October 2023. The study had three main goals. Firstly, to determine how altitude affects the composition and diversity of butterfly species in the Mpanga/Kipengere Game Reserve. Secondly, to assess how habitat impacts the composition and diversity of butterfly species in the same reserve. Lastly, to evaluate the effect of human activities on butterfly species composition and diversity in both the Mpanga/Kipengere Game Reserve and the adjacent Farmlands. The study was conducted between July 2021 and June 2022 at three different altitudinal levels low altitude, mid-altitude, and higher altitude ranging from 1000m to >2000 above sea level. To study the diversity and similarities in species composition between habitats, butterflies were collected using baited traps and sweep nets. A 1000m long line transect was used in each site for sampling. Shannon Index was employed to calculate diversity, while variations were tested using ANOVA and TUKEY-HSD. Bray- Curti's dissimilarities were used to identify similarities in species composition. The results observed during the study are as follows: A total of 2091 butterfly specimens from 5 different families, which included 124 species were observed. Among these species, there were 2 endemic ones, namely Charaxes Congdon and Harpendyreus Juno. The research showed a significant difference in butterfly species diversity based on altitude, with the Mid-Altitude having higher diversity (P < 0.001). However, there was no significant difference in butterfly species diversity between different habitats (Bray-Curtis’s value < 0.23). Furthermore, the study reveals that Mpanga Kipengere Game Reserve has higher butterflies’ diversity compared to surrounding Farmlands. It is also observed that 77% of the species were recorded in April when there was high temperature and rainfall. These findings are crucial for ecological monitoring and the evaluation of the MPKGR ecosystem. The study concluded that: There is a significance difference in butterfly species composition and diversity between altitudes. There is no significance difference in species composition and diversity between vegetation types. Therefore, the variation is influenced by altitudes rather than habitat types. Butterfly species composition and diversity is higher in MPKGR compared to surrounding farmlands. Therefore, the study find that human activities have direct impact on butterfly species composition and diversity. Most of butterfly species recorded immediately after intensive rain season compared to dry season.
Deforestation drivers and effects of livestock grazing on forest structure and composition in the coastal forests of Kilwa District Tanzania
(Sokoine University of Agriculture, 2024-05) Kashenge Salhina Shaban
Coastal forests of Eastern Africa hold considerable importance for the communities residing adjacent or within including forage provision to both domestic and wild ungulates among other ecosystem services. However, the coastal forest ecosystems of Tanzania are facing pressure due to increasing detrimental anthropogenic activities including massive livestock influx which may affect its integrity and vital roles. The present study aimed to provide a better understanding of the effects of livestock grazing on the woody plant composition, vegetation structure, and regeneration capacity of the coastal forests and local communities’ perception of the contribution of livestock grazing and other human activities to the change in land cover of landscape comprising coastal forests in southern Tanzania. The study was conducted in Kilwa District, Lindi, Southern Tanzania. Data collection involved a household survey and ground vegetation survey and analysis of Landsat satellite images. Results indicated that coastal forests at the study site had experienced a 45% decline in cover between 2007 and 2022 at the rate of -3% loss per year, to which interviewed respondents also agreed. Further, 29% of farmland area has increased within the past 15 years. The results revealed further that crop cultivation, livestock grazing, and charcoal production are among the major drivers for forest cover loss. Furthermore, results indicated no and low grazing intensity had higher plant species richness, density, and diversity contrary to moderate and heavy grazing intensities. The moderate and heavy grazing intensities also had low seedling density and diversity. Livestock grazing has also negatively affected the stem distribution of seedlings, saplings, poles, and trees indicating degradation of the coastal forests. It can be concluded from these findings that grazing affected plant species composition, diversity indices, and stem densities in the studied coastal forests. Low grazing intensity had higher diversity indices, stem density, and regeneration status similar to or better than no grazing. Therefore, low grazing is suitable under low stocking rates for livestock due to its insignificant effect on woody species structure, composition and regeneration potential/seedling, and sapling density. It is suggested that urgent interventions are required to ensure controlled grazing that halts heavy grazing and detrimental human activities in the coastal forests within village lands. Also, further research involving large-scale study and long-term cattle and goat grazing experiments with varied grazing intensities/stocking rates to discern proper carrying capacities and effects on biophysical factors such as soil, water, vegetation, and wildlife resources in the landscapes with ample coastal forest resources. This information is useful for informing sustainable conservation strategies of coastal forests at the study site and elsewhere with similar environments.
Assessment of wildlife road kills along urbanization gradient in Morogoro Municipality, Tanzania
(Sokoine University of Agriculture, 2023-05) Mariki, Heavenlight Livingstone
Roads can adversely affect wildlife in two main ways: indirectly, by destroying or dividing their habitats, and directly, by influencing animal collisions with vehicles. There is insufficient of studies regarding wildlife road killing in urban areas, particularly in Morogoro municipal. In order to assess the extent and context of road kill among urban wildlife. The study examined (i) how wildlife road kill composition changes across the urban zones and how road features impact the occurrence of road kills within the municipality. (ii) Assessing conservation awareness among drivers on wild animal kills incidences. Systematic counts of all road kills was conducted along five roads transects cutting across the urbanization gradient in the study area from November to May 2024. Further, questionnaires were administered to drivers within Morogoro municipal to understand the experiences and knowledge on wild animals. A descriptive analysis was employed to show kill abundance across the urbanization zones. Analysis of Variance (ANOVA) was used to compare roadkills between urban zones and within animal taxa respectively. The results showed that, insects had the highest kill abundance and birds had the lowest. There was no significance difference in the overall abundance of road kills between the urban zones. Nevertheless, there was a notable variation in taxa abundance across the urban zones. Speed and animal taxa had a significant positive influence on the number of road kills. Binomial GLM modeling was employed descriptive analysis supported with to understand the factors the mostly influence the perceptions and conservation awareness on the wildlife and animal road kills in urban landscapes. The results revealed that animal collisions occurring outside urban areas (55%) were the most prevalent form of accidents, with mammals being the primary affected group (35.7%). Further, outside of urban areas, the statistical model revealed that the likelihood of animal collision on he road increased as driving hours decreased, whereas inside urban areas, the likelihood of animal collisions increased as driving hours increased. Overall, this study emphasizes the substantial impact of road kills on diverse taxa(classes) and identifies key contributors to these incidents. Three major environmental concerns emerge: the threat posed to urban ecosystem functioning by the significant number of animals killed on roads, including crucial pollinators and seed dispersers like fruit bats and insects; the negative impact of designated road over-speeding on wildlife and the lack of conservation status data for a large proportion of road kills, particularly among insects, underscoring the need for increased efforts in investigating invertebrates(insects) biodiversity in urban landscapes.
The effects of different grazing intensities on soil properties in Miombo Woodlands of Tanzania
(Sokoine University of Agriculture, 2024-05) Mchelu, Hadija Ahmad
This study was conducted at Miombo woodlands in Tanzania to enhance the sustainability of miombo woodlands in response to the increasing grazing pressure in miombo woodlands, driven by agricultural expansion, population growth, and rising demand for livestock products, has led to soil degradation, land scarcity, and socio-economic conflicts among land users. The study aimed to evaluate dynamics of selected soil physical and Soil organic carbon under different grazing intensities for sustainability of Miombo woodlands. The research used a purposive sampling and random sampling design. Grazing intensity was evaluated through two approaches: livestock stocking rates based on official records and a scoring method derived from field observations. Soil organic carbon (SOC) content was determined from topsoil samples collected from 188 plots whereas soil hydraulic conductivity (Kfs) and underground Water movement was estimated in 117 of these plots. Statistical analysis was carried out using R® software version 4.4.2, using Linear Mixed-Effects Models (LMM) and Gamma Generalized Linear Mixed-Effects Models (GLMM) with a random intercept. The results showed a slight agreement (k=0.14) between the stocking rate and scoring methods on classification of grazing intensities. Significant positive effects of increasing grazing intensity GI were observed on bulk density (BD) and preferential flow (P<0.001), while significant negative effects (P<0.001) were observed on SOC, (Kfs), percentage dye cover, and uniform infiltration flow. The mean SOC ranged from 2.38 ± 0.84% under light grazing intensity to 1.42 ± 0.75% under high grazing intensity. Kfs showed a mean range of 100.08-± 65.56 mmhr-1 under light grazing intensity to 27.28 ± 22.99 mmhr-1 under high grazing intensity, while BD ranged from 1.64 ± 0.12 gcm-3 under high grazing intensity to 1.34 ± 0.17 g cm-3 under light grazing intensity. The study recommends developing and implementing proper sustainable livestock management practices made to the specific conditions of Miombo ecosystems. Adhering to sustainable
Population ecology and threats of bee species across vegetation types in Mgori Forest Reserve, Singida District, Tanzania
(Sokoine University of Agriculture, 2024-05) Mponzi, Alphoncina Ephraim
Bees are among pollinator groups of importance in promoting and maintaining biodiversity and food production through provision of pollination services. This makes identifying and monitoring communities of bee species, a crucial step in the process of conservation. Forest vegetation types are among determinant of bee species composition and diversity. With the continued loss of suitable habitats for bees, conservation of bee species should begin with information on their presence. Mgori forest reserve is surrounded by villages with farms planted with crops such as sunflower, which is pollinator dependent, hence they benefit from pollination services from bees inhabiting the forest. To ensure inclusive conservation for the survival of bee species this study aimed at determining the composition, diversity and threats of bee species in Mgori forest reserve, across the vegetation types namely open woodland, thickets and the mosaic of open woodland and thickets, which are found within the forest reserve. Systematic sampling was used in the study, whereby plots were established in the forest. To collect bees on each plot, pan traps and sweep nets were used.Threats to bees were also observed and recorded on each plot, thereafter plots with observed threats were characterised as disturbed plots and those with no observed threats were characterised as undisturbed sites. Additionally, coordinates and elevation point of the sites were also recorded. Bee species composition was the list of bees identified. Bee species richness and abundance were the number of species recorded and the number of individuals per species respectively. Shannon-Wiener diversity index was used to calculate the diversity of bees in the forest for disturbed and undisturbed sites. Kruskal-Wallis test was used to compare Richness and Abundance of bee species, across open woodland, thickets and the mosaic of thickets and open woodland and the Duncan post hoc was performed for both species richness and abundance. Detrended correspondence analysis was used to find the relationship between species composition and environmental variables and generalized linear mixed effect models were used to find the relationship between environmental conditions and bee species richness and abundance. All data was analysed through the R Software. Threats to bees were described and presented through graphs and tables using SPSS software. And then Chi-Square Test was used for comparison across studied sites to determine the variation of bee species richness and abundance between undisturbed and disturbed sites. A total of 508 bees were collected from the studies sites in Mgori forest reserve; the Dominant family was the Halictidae family, followed by the Apidae and Megachilidae was the least recorded family. Species composition significantly varied between thickets and open woodland types of vegetation, whereby open woodland had higher composition, richness and abundance than thickets. Environmental conditions were associated with species abundance but not richness; particularly elevation had a significant influence on species abundance. On the influence of threats on bee species, the human threats recorded were found to be consistent with resource needs in the forest. The threats recorded were debarking, grazing, trails, logging, fire scars and agricultural encroachment. The most consistent evidence was the presence of trails in the forest and grazing across all three vegetation types. The comparison of bee species richness, abundance and diversity showed that, there was significant difference in bees across the disturbed and undisturbed sites. Whereby bees were more present in undisturbed sites than disturbed sites. There was no difference in the calculated Shannon- Wienner diversity index and abundance of bees between the disturbed and undisturbed sites. The study has revealed the composition of bees in Mgori forest reserve, which can serve as information for future ecological study in the forest. It has also revealed human threats in the forest that hinder conservation in the forest, as well as influencing the presence of bees in the forest. Particularly their richness across space. In the management of the forest, it is important to consider thickets and open woodland vegetation types found within the forest, since they serve as separate supplementary habitats to these forest species. The apparent human threats in the forest threaten its conservation. As a result, there is a need for the forest patrons and the communities living adjacent to the forest, to work on improving the guarding and conservation of the forest. This is because of the benefits such as pollination services that can be obtained from Mgori forest.
Assessment of the impacts of community participation on the conservation of mangrove resources: A case study of Lindi district, Tanzania.
(Sokoine University of Agriculture, 2001) Machumu,Milali Ernest
The word mangrove refers either to the plants of tropical intertidal forest communities or to the community itself (Semesi, 1991). Mangroves are trees and bushes growing below the high - water level of spring tides (FAO, 1982). "Mangrove" is a general term applied to an association of physiologically specialised plants inhabiting muddy swamps, creeks, deltas and sheltered sea coasts periodically inundated by tides (Banyikwa and Semesi, 1986). The trees are only one component of the complex mangrove ecosystem, which includes associated bodies of water, substrates as well as a variety of other plants, animals and micro-organisms (Semesi, 1986).
Growth, yield and wood properties of teak (Tectona grandis) provenances at longuza forest plantation, Muheza District, Tanzania
(Sokoine University of Agriculture, 2024-05) Opiyo, Anthony Phanuel
A comprehensive study was conducted at Longuza Forest Plantation in Tanzania to enhance the production of Teak (Tectona grandis) in response to increasing demand for improved Teak provenances for productive plantations. The study aimed to evaluate the growth performance and wood properties of 12 provenances established in 2011, comprising 41 families. The experiment used a randomized complete block design with 8 replications, each plot containing 6 trees. The growth performance assessment included survival, diameter at breast height (Dbh), height (Ht), basal area (BA), volume (Vol), and mean annual increment (MAI). Additionally, the study examined stem straightness and the physical properties. Statistical analysis was carried out using SAS® software version 9.4, NPAR1WAY and rank procedures. The results showed non- significant differences (p > 0.05) in survival among provenances but highly significant differences (p < .0001) for Dbh, Ht, Vol, BA, and MAI, the average values for these parameters were 68.70 ± 5.64 %, 21.35 ± 4.04 cm, 18.65 ± 2.2 m, 304.83 ± 135.37 m3 ha−1, 9.96 ± 3.60 m2 ha−1, and 27.71 ± 12.30 m3 ha−1 yr−1 respectively. The study identified superior performing provenances, including the East Africa Longuza seed stand, East Africa Longuza Provenance Trial, and East Africa Longuza Progeny Trial. Furthermore, the results revealed significant variation in stem straightness among provenances with the average score of 1.9 ± 0.8. Provenances like East Africa Mtibwa, CSIRO Thailand, and East Africa Longuza seed stand showed superior stem straightness. However, no substantial variations in physical properties were observed among the provenances. The average basic density was 0.571 ± 0.059 g cm−3, with mean ranging from 0.469 ± 0.053 in CSIRO Thailand to 0.545 ± 0.071 g cm−3 in East Africa Longuza Progeny Trial. Based on the findings, the study recommends planting East Africa Longuza seed stand, East Africa Longuza Provenance Trial, and East Africa Longuza Progeny Trial in pilot plantations at Longuza and in areas with similar climatic and soil conditions. Furthermore, the study
Plant communities of Kilombero wetlands in Tanzania: structure, invasion and cattle grazing
(Sokoine University of Agriculture, 2014) Macrice ,Andrew Samora
Wetlands arc dynamic ecosystems appreciated worldwide for supporting biodiversity. sustaining livelihoods and climate change mitigation and adaptation. However, the increased degradation of wetlands and changes in their plant species composition and diversity due to anthropogenic disturbances, alterations of natural environmental conditions and plant invasions is an increasing global concern. Thus, to restore the species composition and diversity and protect existing plant communities in wetlands, timely understanding of important factors that regulate and maintain plant community structure as well as how communities become vulnerable to alien plant invasions is essential. Therefore, using herbaceous vegetation, studies were conducted to investigate key drivers of spatial heterogeneity in plant species composition, richness and diversity, to examine invasibility of plant communities and to assess how large domestic herbivores (cattle) select foraging sites within Kilombero Valley Floodplain wetland. Tanzania. The results show that patterns of spatial variation in plant species composition. richness and diversity were associated with natural environmental conditions, human disturbance and spatial position variables. In particular, variation in species composition of all plant species and functional groups (graminoids. forbs and shrubs) were best explained by natural environmental conditions (total organic carbon, elevation and distance from Kilombero River) and human disturbance (cow dung density and distance to cattle holding pen area (kraal)). Total species richness and the richness of functional groups decreased with the increase in distance from the river, suggesting that, annual flooding is important in the study site. Grazing reduced total species diversity and the diversity of graminoids possibly through changing local nutrient balance. Most shrub species were found on relatively high ixelevations, and shrub richness related negatively to total organic carbon suggesting that shnibs are less tolerant to inundation and high levels of soil fertility. Plant community properties such as species evenness and bioinass have rarely been used in biological invasion studies. Interestingly, these properties promoted community resistance against invasion of alien plant species Echinochloa colona through reducing its abundance. Moreover, it appears that grazing intensity creates gaps which are occupied by fast growing opportunistic species such as £. culona which may then alter the structure of native plant communities. Thus, disturbed areas with rich environmental resources (e.g. light. water, nutrients) and low plant biomass and evenness of native species are hot spots for plant invasions. Cattle selected foraging sites using a nesting feeding choice model. On a larger scale. cattle selected patches with low diversity, at high elevations, and at longer distances from agricultural fields. Moreover, cattle selected patches with a higher abundance of palatable plant species with high biomass at large scale. It appears that once the large scale patch is selected, cattle tend to graze on small patches with high plant species richness and moderate biomass to achieve nutritional balance and maximize energy gains. In conclusion, maintenance of plant species richness and biomass together with optimal stocking rates could improve cattle production and rangeland quality. Since natural environmental conditions and human disturbance variables shapes plant community structure. intensification of human activities (e.g. overgrazing by livestock) and alterations of natural environmental conditions (e.g. through water diversion and drainage) should be discouraged. Finally, improved management strategies including increasing biomass and evenness of native species together with reduction in grazing pressure may reduce community vulnerability to alien plant invasions and improve biodiversity conservation.
Beekeping in magu district, tanzania: status, constraints and contributions to livelihoods
(Sokoine University of Agriculture., 2011) Selele Igunda John
This study was conducted in six villages of Magu district, namely: Igekemaja. Lugeye, Nyalikungu, Ng'haya. Manala and Mkula. The aim was to assess status, constraints and contributions of beekeeping to household income. Data were collected from 180 respondents included both beekeepers and non-beekeepers through household questionnaire surveys, direct observations, interviews with key informants and two PRA techniques. The level of beekeeping community knowledge was analyzed using index scale of awareness. The mean difference in incomes between beekeepers and non-beekeepers was tested using Z-test. The significance of the constraints to beekeeping was analyzed using/5. The relationship between beekeeping education and honey hunting was examined using Pearson correlation. The relationship between socio-economic factors, the beekeeping extent and beekeeping community knowledge was analyzed using multinomial regression. Of the 180 respondents, only 13 were beekeepers with 74 beehives, whereas IO5were non-beekeepers. 62 were honey hunters and about 110 colonies were hunted in 2009. Respondents with beekeeping education were more likely to practice beekeeping and neither of them hunted honey. Four levels of beekeeping community knowledge were identified: 8 respondents (4.4%) were found with “high knowledge". 95 (52.8%) with "moderate knowledge”. 70 (38.9%) with "low knowledge” and 7 (3.9%) with "no knowledge". Alternative sources of income attributed to low community participation in beekeeping. The annual household income for beekeepers was TAS I 023 000±17l 484.69 (Mean±Standard Deviation) and TAS 835 700±l 011 058.71for non-beekeepers. Eight constraints to beekeeping were identified with lack of beekeeping knowledge, fear of honeybee sting and shortage of bee fodder being three top most. Others were lack of capital, alternative income sources and shortage of colonies.The study concludes that for honeybee resources to be utilized fully and sustainably, the community must be provided with beekeeping education and facilitated to obtain modem beekeeping equipment.

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