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Climate information can help vulnerable populations anticipate disasters before they happen and enable communities prepare for and cope with them. A complementary log-log regression model based on quantitative study in coastal communities in Tanzania was used to assess the likelihood of the rural poor, rural non poor, urban poor, and urban non poor to receive early warning information about flood, drought and other disasters. Individuals in the urban poor category were 35% less likely to receive early warning information about flood, drought and other disasters whereas urban non-poor residents were 49% more likely to receive same. This disadvantage to the urban poor persists even when adaptive capacity, geographical location and socio-environmental factors are accounted. Nuclear households consisting of a male head and female partner who have children or not had higher likelihood of receiving early warning information on flood, drought and other disasters (OR = 1.47, p < 0.001) compared with their counterparts in female-centred households (no husband or male partner). Residents with tertiary education were more likely (OR = 1.91, p < 0.001) to report that they had received early warning information about flood, drought and other disasters compared with their counterparts without any formal education. This zero-order relationship was completed mediated by geographical location and socio-environmental factors in the multivariate model. The results underline the key role access to climate- and disaster-related information play in enhancing adaptive capacity to reduce vulnerability to natural hazards, as well as the importance of targeting the most vulnerable households in policy interventions to improve resilience in the face of a changing climate.

One of the most important defining characteristics of groundwater quality is pH as it fundamentally controls the amount and chemical form of many organic and inorganic solutes in groundwater. Groundwater data are frequently characterized by a wide degree of variability of the factors which possibly influence pH distribution. For this reason, it is challenging to link the spatio-temporal dynamics of pH to a single environmental factor by the ordinary least squares regression technique of the conditional mean. In this study, quantile regression was used to estimate the response of pH to nine environmental factors (As, Cd, Fe, Mn, Pb, turbidity, electrical conductivity, total dissolved solids and nitrates). Results of 25%, 50%, 75% quantile regression and ordinary least squares (OLS) regression were compared. The standard regression of the conditional means (OLS) underestimated the rates of change of pH due to the selected factors in comparison with the regression quantiles. The effect of arsenic increased for sampling locations with higher pH values (higher quantiles) likewise the influence of Pb and Mn. However, the effects of Cd and Fe decreased for sampling locations in higher quantiles. It can be concluded that these detected heterogeneities would be missed if this study had focused exclusively on the conditional means of the pH values. Consequently, quantile regression provides a more comprehensive account of possible spatio-temporal relationships between environmental covariates in groundwater. This study is one of the first to apply this technique on groundwater systems in sub-Saharan Africa. The approach is useful and interesting and has broad application for other mining environments especially tropical low-income countries where climatic conditions can drive rapid cycling or transformations of pollutants. It is also pertinent to geopolitical contexts where regulatory; monitoring and management capacities are weak and where mining pollution of groundwater largely occur.

There are several idle lots and spaces in cities and towns in Ghana due to poor land use and physical planning as well as pressure for privately-built, low density residential houses. This project tested the idea of using idle, unmanaged urban spaces in Cape Coast to produce multiple ecosystem services in the context of multifunctional land use: food, landscape beautification, income, and environmental protection. Two sites which were bushy and seemingly used for nefarious activities were transformed into greenhouse vegetable production. The greenhouse project generated short term jobs for eight young people of equal gender distribution, and one additional person produced vegetables on a portion of vacant, backyard residential lot in an urban residential area. Premium quality tomatoes were harvested from the greenhouse production, while garden eggs and pepper were harvested from the outdoor production. Production outputs were either sold to nearby eateries and residents, or used by the project members as subsistence. The landscaped spaces around the greenhouses attracted families nearby to bring their children to play in the area while curiously learning about the crop production in the greenhouse. Thus, the project provided greenspace and opportunity for active living and learning for children and families in their neighbourhood on a lot that was previously unused and inaccessible. The project was also visited by the AgriCorps team (USA) who found it promising and worthy of up- and out-scaling. A highly successful dissemination event brought together stakeholders (local farmers, representatives from the vegetable group of market women association of Cape Coast, Regional and Metropolitan Agricultural Offices, media, academia, local chiefs and opinion leaders, and the general public) who were very impressed by the project. Some were even motivated to start their own production on idle spaces around their homes. The media also showed large interest for the project. Key lessons learned include (i) the need to formalize access to and use of vacant, idle, unmanaged urban spaces for such multifunctional land use purposes, (ii) accurate timing of first production cycle for the dry season to fetch premium price for the produce, (iii) establishing stable markets for the produce, trialling and using different crops to understand what works best and to reduce risks, and (iv) continuous engagement of stakeholders to sustain interest in the projects. Overall, edible urban landscapes could provide food, jobs, beautiful landscapes, environmental protection, and greenspace for active living in cities and towns.

Coastal Tanzania, a region of historical and geopolitical importance in the western Indian Ocean, is a place where the problem of rapid environmental change is inextricably entwined with the challenges of development. In this region, although the fingerprint of the anthropocene has been discernible over the last century, there is paucity of research on how the population has interacted with the changing environment to generate disparities in perceptions of climate change and human health outcomes. The objectives of this thesis are four-fold: to assess barriers to climate change adaptation based on context (place), to explain group disparities in barriers to climate change adaptation based on relative well-being (income poverty), to evaluate description-based and experienced-based perceptions of environmental change, and to analyse the relationship between subjective and objective health status, on the one hand, and public perception of human health risks associated with climate change, on the other hand. Cross-sectional survey data on 1253 individuals (606 males and 647 females) were collected during March and September 2013 to make inferences about the population in this region. This was complemented with 50-year (1960-2009) meteorological data on rainfall and temperature. Multivariate regression, counterfactual decomposition, multinomial regression and time-series were used in the quantitative analyses. The results show that barriers to adaptation to climate change mainly reflect strong place-specific differences among the population. Disparities in barriers to climate adaptation between poor and nonpoor residents are mainly attributable to group differences in the magnitudes of the determinants (endowments) rather than group differences in the effects of the determinants (coefficients). There is agreement between respondents’ perceptions of temperature change and available scientific climatic evidence over the 50-year period although results on perception of rainfall patterns were varied. Generally, higher ratings on subjective health status were associated with lower scores on perceived human health risks of climate change. Concerning objective health status, the results were varied. Individuals who indicated that they had been previously diagnosed with hepatitis, skin conditions or tuberculosis had lower scores on perceived health risks of climate change unlike their counterparts who stated that they had been previously diagnosed with malaria in the past 12 months or had been diagnosed with HIV/AIDS. These relationships persist even when biosocial and sociocultural attributes are taken into consideration. The results underscore the complex ways in which objective and subjective health interact with biosocial, sociocultural and contextual factors to shape public perception on health risks associated with climate change. At least two policy implications originate from the findings of this dissertation. First, disentangling the complex indirect pathways among barriers to climate change adaptation, place-based attributes and relative well-being is a challenging research endeavour that requires the development of new partnerships to provide more accurate data. Given the complex mechanism by which experiential climate change acts, collectively, with compositional and contextual factors to influence public perception of climate change-related human health risks, it is probably apt to approach the study of environmental change and human health using integrative frameworks.

Heavy metal accumulation in the food chain is an issue of global concern because it eventually leads to toxic effects on humans through the water we drink, contaminated soils, crops, and animals. Reports of toxicant levels in environmental media (air, water, and soil) and biota in Ghana were sought in SCOPUS, PubMed, MEDLINE, and EMBASE. Of 1004 bibliographic records identified, 54 studies were included in evidence synthesis. A disproportionately large number of papers (about 80%) focused exclusively on environmental media. Papers focusing on biomonitoring and human health were relatively few. Studies reported a high degree of spatial variability for the concentrations of 8 metals in groundwater. Generally, heavy metal concentrations in soil reported by the studies reviewed were higher than metal concentrations in riverine sediments. Urine and hair were the most common biological markers of heavy metal exposure used by the studies reviewed unlike nails, which were sparingly used. By and large, published results on the levels of heavy metals in goldmine and non-mine workers yielded contradictory results. Mostly, concentrations of heavy metals reported by the studies reviewed for nails were higher than for hair. A high degree of variability in the heavy metal concentrations in human subjects in the studies reviewed is likely due to heterogeneity in physiological states, excretion profiles, and body burdens of individuals. These, in turn, may be a product of genetic polymorphisms influencing detoxification efficiency.

There is a need for cost-effective methods to reduce nitrogen pollution from agriculture. Marginal abatement cost (MAC) curves for nitrate-nitrogen pollution in an agricultural watershed are evaluated using estimated crop yield and nitrate pollution production functions for alternative cropping systems. The cropping systems considered in this study included i) two grain corn-based cropping systems; ii) two potato-based cropping systems; and iii) a vegetable-horticulture system, managed under conventional tillage (CT) and no-till (NT). The cost-effective potato-based cropping system which met the Health Canada maximum contaminant limit (MCL) for nitrate-N, with the highest gross margin ($6973 ha-1) and lowest abatement cost ($395 ha-1) was a potato-barley-winter wheat-potato-corn rotation under no-till (PBWPC-NT). Similarly, among the vegetable-horticulture cropping systems, potato-winter wheat-carrot-corn rotation under CT (PWRC-CT) generated the highest gross margin and lowest on-farm abatement cost ($680 ha-1). As the Health Canada allowable limit on nitrate-N pollution was relaxed (i.e., less stringent), the cost-effective corn-based cropping system shifted from a rotation involving corn-corn-alfalfa-alfalfa-alfalfa under CT to corn-corn-corn-alfalfa-alfalfa under NT.

The eco-efficiency index (EEI) framework has been used to determine economically and environmentally optimal nitrogen (N) fertilizer application rates for some pollutants (such as greenhouse gas emissions) for selected agricultural production systems. However, previous EEI applications have not examined N application rates linked to nitrate-N loss from crop production. The research gap is surprising given the importance of nutrient N in crop production and concerns with nitrate-N in groundwater systems. Eco-efficiency of crop production systems are increased for farm management practices which generate higher economic returns and lower negative environmental impacts and, therefore are considered more eco-efficient. Data for the analysis were generated using the SWAT biophysical simulation modeling. The cropping systems evaluated in this study included: i) corn-based cropping systems involving corn-corn-alfalfa-alfalfa-alfalfa (CCAAA), and CCCAA rotations; ii) potato-based cropping systems involving potato-corn-barley-potato-corn (PCBPC) and PBWPC; and iii) vegetable-horticulture cropping system involving potato-winter wheat-potato-carrot-corn (PWRC) all managed under conventional tillage (CT) and no-till (NT) systems. Estimated eco-efficient N fertilizer rates were substantially lower than current NMP-recommended rates (NMP N rates) and the maximum economic rate nitrogen fertilization (MERN). However, the actual amounts depended on the crop and rotation system. CCAAA-CT was the most eco-efficient rotation choice among the corn-based cropping systems considered. Similarly, PCBPC-CT was the most eco-efficient choice among the potato-based production systems. In addition, when the NMP-recommended N rate was replaced by the EE N rate for the vegetable horticulture cropping system, the eco-efficient cropping system shifted from a rotation involving CT to a NT system. Eco-efficient N fertilization rates that explicitly simultaneously considers economic and environmental dimensions of cropping system performance will require substantial trade-offs between farm returns and reduction in nitrate pollution.

Alstonia boonei De Wild is a herbal medicinal plant of West African origin, popularly known as God's tree or “Onyame dua”. Within West Africa, it is considered as sacred in some forest communities; consequently the plant parts are not eaten. The plant parts have been traditionally used for its antimalarial, aphrodisiac, antidiabetic, antimicrobial, and antipyretic activities, which have also been proved scientifically. The plant parts are rich in various bioactive compounds such as echitamidine, Nα-formylechitamidine, boonein, loganin, lupeol, ursolic acid, and β-amyrin among which the alkaloids and triterpenoids form a major portion. The present paper aims at investigating the main research undertaken on the plant in order to provide sufficient baseline information for future work and for commercial exploitation.

This study sets out to explore one of the most important questions for alleviating poverty in sub-Saharan Africa namely: why are advancements in agricultural technology not taking root in this region? Using data from deep interviews of 42 smallscale farmers in Ghana and Cameroon, a conceptual analysis of drivers and factors of agricultural technology adoption in this region is made and represented as causal loop diagrams. Interviews also provide a basis for weighting factors that farmers consider before adopting a new technology. These weights are then used to run a systems dynamics model with a hypothetical population of 10.000 farmers to see the effects of different drivers of technology adoption on the adoption rate and number of adopters over a 25 year period. Results show that most farmers have a bethedging strategy as they try to minimize risks of production failures. While certain factors like scale of production, long-term considerations, the history of success of past technologies, and the endorsement of technologies by opinion leaders may be important, many other factors do influence decisions to adopt new technologies. This limits any silver bullet strategy towards solving the problem of limited diffusion of agricultural technologies in this region. Addressing such a problem therefore calls for a much more holistic approach., Science, Technology & Innovation Studies