Exploring the variability among smallholder farms in the banana-based farming systems in Bukoba district, Northwest Tanzania

A study was conducted in the high and low rainfall zones in the banana-based farming system in Bukoba district, Tanzania, to explore the variability among household characteristics and farm productivity. Approaches used included a participatory rural appraisal, rapid system characterization, surveys and detailed farm monitoring in two villages, one from each zone in 2005 through 2006. Based on a wealth-ranking, four household resource groups with decreasing wealth were identified: Resource group 1 > Resource group 2 > Resource group 3 > Resource group 4, distinguished by domestic assets, livestock ownership and labour relations. Through principal component analysis using additional variables defined by research team, three Functional Resource Groups from among the four Resource groups at each rainfall zone were identified distinguished by: soil fertility management, food security and farm and off-farm income as important indicators of variability. Further detailed monitoring over 14 months (from March, 2006 through May, 2007) in at least three households from each functional resource group showed that N, P and K balances among land use types and farms were driven by levels of organic inputs used and were also related to wealth and dependence on off-farm activities. However, all households were net food buyers, implying food insecurity. In addition, off-farm activities and off-farm income were important livelihood survival strategie

Diet dynamics and feeding strategies of Hilsa kelee (Cuvier, 1829) and Valamugil buchanani (Bleeker, 1853) in the Pangani Estuary, Tanzania: Insights from stomach contents and fatty acid biomarkers

Stomach contents and fatty acid (FA) biomarkers were used to investigate the diet and feeding strategies of the marine fish species Hilsa kelee and Valamugil buchanani, across three Pangani estuarine zones (about 7 km apart). The three zones depict heterogeneous distribution of trophic resources along the longitudinal estuary gradient. Despite ecological index and FA trophic niche widths indicating high overlap of trophic resources, the permutational multivariate analysis of variance revealed significant interspecific variations in diet and FA compositions. This highlights the importance of using statistically supported tools when drawing inferences on the diet dynamics of estuarine fish. The dominant diatom and detritus diets reflected the high herbivory C22:6(n-3):C20:5(n-3) and omnivory C18:1(n-9):C18:1(n-7) FA trophic indices of V. buchanani. The diatoms and copepods dominating the diet of H. kelee concurred with the species’ higher carnivory C22:6(n-3):C20:5(n-3) and lower omnivory C18:1(n-9):C18:1(n-7) FA biomarkers. The diet niche breadth index, the Amundsen feeding strategy diagrams, and the FA trophic niche suggest that V. buchanani exhibits a generalist feeding strategy, and H. kelee a mixed feeding strategy that is intermediate between a specialist and a generalist. Due to these differences, it is suggested that V. buchanani demonstrates a higher degree of resilience to anthropogenic disturbances than H. kelee in the Pangani estuary.

Exploring the variability among smallholder farms in the banana-based farming systems in Bukoba district, Northwest Tanzania

A study was conducted in the high and low rainfall zones in the banana-based farming system in Bukoba district, Tanzania, to explore the variability among household characteristics and farm productivity. Approaches used included a participatory rural appraisal, rapid system characterization, surveys and detailed farm monitoring in two villages, one from each zone in 2005 through 2006. Based on a wealth-ranking, four household resource groups with decreasing wealth were identified: Resource group 1 > Resource group 2 > Resource group 3 > Resource group 4, distinguished by domestic assets, livestock ownership and labour relations. Through principal component analysis using additional variables defined by research team, three Functional Resource Groups from among the four Resource groups at each rainfall zone were identified distinguished by: soil fertility management, food security and farm and off-farm income as important indicators of variability. Further detailed monitoring over 14 months (from March, 2006 through May, 2007) in at least three households from each functional resource group showed that N, P and K balances among land use types and farms were driven by levels of organic inputs used and were also related to wealth and dependence on off-farm activities. However, all households were net food buyers, implying food insecurity. In addition, off-farm activities and off-farm income were important livelihood survival strategie

Seed fairs and the case of Marambo village, Nachingwea district, Tanzania Implications of local informal seed supply and variety development for research and extension

SIGLEAvailable from British Library Document Supply Centre-DSC:6077.203637(101) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

HIV prevalence and associated risk factors among female sex workers in Dar es Salaam, Tanzania:tracking the epidemic

Since 2014, HIV care and treatment services among key populations including female sex workers (FSWs) have intensified in Tanzania. We sought to track the epidemic among FSWs in Dar es Salaam, Tanzania. We conducted a cross-sectional integrated bio-behavioral survey using respondent-driven sampling and a structured questionnaire. Blood was drawn for HIV testing. Modified Poisson regression was used to determine factors associated with HIV infection. We recruited 958 FSWs (median age 26 years) of whom 952 consented to HIV testing. The HIV prevalence was 15.3% (95%CI: 12.5-18.6). Factors associated with higher HIV prevalence included old age (25-34 years: aPR 2.38; 95%CI: 1.23, 4.60 and over 35 years: aPR = 6.08; 95%CI: 3.19, 11.58) and having experienced sexual violence in the past year (aPR = 1.94; 95%CI: 1.34, 2.82). Attaining higher education level was associated with lower HIV prevalence (aPR = 0.51; 95%CI: 0.36, 0.73 for primary school level and aPR = 0.20; 95%CI: 0.08, 0.46 for secondary school level and/or above). The HIV prevalence among FSWs in Dar es Salaam has decreased by half since 2013. Prevention strategies should target older FSWs, aim to educate young girls, and institute approaches to mitigate violence among FSWs

Communicating complexity: Integrated assessment of trade-offs concerning soil fertility management within African farming systems to support innovation and development

African farming systems are highly heterogeneous: between agroecological and socioeconomic environments, in the wide variability in farmers' resource endowments and in farm management. This means that single solutions (or 'silver bullets') for improving farm productivity do not exist. Yet to date few approaches to understand constraints and explore options for change have tackled the bewildering complexity of African farming systems. In this paper we describe the Nutrient Use in Animal and Cropping systems - Efficiencies and Scales (NUANCES) framework. NUANCES offers a structured approach to unravel and understand the complexity of African farming to identify what we term 'best-fit' technologies - technologies targeted to specific types of farmers and to specific niches within their farms. The NUANCES framework is not 'just another computer model'! We combine the tools of systems analysis and experimentation, detailed field observations and surveys, incorporate expert knowledge (local knowledge and results of research), generate databases, and apply simulation models to analyse performance of farms, and the impacts of introducing new technologies. We have analysed and described complexity of farming systems, their external drivers and some of the mechanisms that result in (in)efficient use of scarce resources. Studying sites across sub-Saharan Africa has provided insights in the trajectories of change in farming systems in response to population growth, economic conditions and climate variability (cycles of drier and wetter years) and climate change. In regions where human population is dense and land scarce, farm typologies have proven useful to target technologies between farmers of different production objectives and resource endowment (notably in terms of land, labour and capacity for investment). In such regions we could categorise types of fields on the basis of their responsiveness to soil improving technologies along soil fertility gradients, relying on local indicators to differentiate those that may be managed through 'maintenance fertilization' from fields that are highly-responsive to fertilizers and fields that require rehabilitation before yields can improved. Where human population pressure on the land is less intense, farm and field types are harder to discern, without clear patterns. Nutrient cycling through livestock is in principle not efficient for increasing food production due to increased nutrient losses, but is attractive for farmers due to the multiple functions of livestock. We identified trade-offs between income generation, soil conservation and community agreements through optimising concurrent objectives at farm and village levels. These examples show that future analyses must focus at farm and farming system level and not at the level of individual fields to achieve appropriate targeting of technologies - both between locations and between farms at any given location. The approach for integrated assessment described here can be used ex ante to explore the potential of best-fit technologies and the ways they can be best combined at farm level. The dynamic and integrated nature of the framework allows the impact of changes in external drivers such as climate change or development policy to be analysed. Fundamental questions for integrated analysis relate to the site-specific knowledge and the simplification of processes required to integrate and move from one level to the next.Crop-livestock systems Soil fertility Smallholders Farm types Simulation modelling