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    Removal of Hg 2+ , Pb 2+ , Zn 2+ and Cu 2+ ions from Contaminated Water Using Caladium bicolor (Wild Cocoyam)
    (Research Square, 2020) Ayim, Emmanuel; Agongo, Julius; Sakyi, Patrick Opare
    Heavy metal persistence in the environment is a global threat and researchers continue to explore low-cost effective technologies for removing these contaminants from the environment. In this study, the ability of Caladium bicolor (biosorbent) to remove lead, zinc, copper and mercury ions from the contaminated water was explored. At 2 ppm metal ion concentration, the biosorbent was able to remove all four metal ions with a low removal efficiency of 79.5% for Hg 2+ and a high of 99.5% for Pb 2+ The effectiveness of the biosorbent, however, decreased when the metal ion concentration was increased beyond 2 ppm. Specifically, the biosorbent’s effectiveness was studied at 5, 10, 25, and 50 ppm metal ion concentrations. Interestingly, the decrease in effectiveness with regards to Pb 2+ was relatively marginal, suggesting a stronger preference of Caladium bicolor for lead. In order to determine optimal conditions required for effective adsorption or high metal removal efficiencies, the effect of biosorbent mass and contact time for equilibration of the biosorbent with the metals were also investigated. While 30 min contact time was found to be adequate for effective metal removal, there was no significant difference in the results obtained when 0.5 g vs 2.0 g of the biosorbent was used. FT-IR analyses also revealed that similar functional groups were responsible for the removal of all the four metals studied.
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    Preliminary Studies of Fecal Sludge Accumulation Rates of Dry Pit Latrines Using Kinect Based 3D Scanning Technology
    (2021) Amo-Boateng, M; Appiah-Effah, E; Afedoh, B. F
    This study entails the findings of the accumulation rates of dry pit latrines in an urban community in Ghana. The results are then compared to that proposed by the World Health Organization (WHO). Over the years, studies have been conducted to get faecal sludge accumulation rates that could be internationally accepted. As a result of the discrepancies in the values obtained over the years, WHO proposed a figure (0.006m3 /person/year) which has been used since the 1950s. Our study was conducted in line with the already conducted studies but using the 3D Kinect technology with the cloud compare software. Based on our findings, we realized that the accumulation rates of dry pit latrines average 0.132m3 /person/year) in Fiapre, Ghana. This study also points out few reasons why there may have been discrepancies in the values obtained by various researchers over the years. We therefore encourage that the methods used in this study be employed in determining the accumulation rates of solids in latrines prior to their design and construction.
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    Physical and mechanical properties of locally cultivated tomatoes in Sunyani, Ghana
    (Scientific African, 2020-10-28) Uba, Felix; Esandoh, Eric Osei; Zogho, Donatus
    The physical and mechanical properties of tomato fruits are very pertinent and crucial in the design of mechanised equipment for harvesting, cleaning, sorting, grading, storing and packaging for transportation from farms to processing plants or market centres. The concept of physical and mechanical properties can be applied to prevent the degradation of tomato fruits during harvesting and processing. The objective of this research is to establish the physical and mechanical properties of locally cultivated tomatoes (Eva F1 variety) in the Bono Region of Ghana. The 3-Dimensional linear characteristics of the samples obtained from linear measurement lead to the conclusion that Eva F1 is spherical and as a result it can undergo both sliding and rolling motions because of the aspect ratio which is between 77.54 to 95.18 and sphericity values above 83.00. The linear measurements also revealed that handling and sorting devices should have an aperture size between 34 and 77 mm for outlet or inlet dimension for mechanisation. An ELE compression machine was used to determine the firmness of different grades of Eva F1 tomatoes (red and yellow). An average compressive force of 16.88 N was found to cause fracture to the cell wall of a ripe (red) tomato while the yellow grade experienced an average force of 21.77 N. An inclined plane was used to determine the coefficient of friction for two different wooden surfaces (smooth and rough wawa boards). Average coefficient of friction values higher than 0.22 are recommended for mechanised material handling equipment and 0.21 or lower for packing boxes suitable for transportation. The research also showed that the best stage for the transportation of tomato is when they are at the yellow stage with low coefficient of friction and can absorb more energy before rupture.
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    Partial Replacement of Cement with Glass Bottle Waste Powder in Concrete for Sustainable Waste Management: A Case Study of Kumasi Metropolitan Assembly, Ashanti Region, Ghana
    (Journal of Civil Engineering Research, 2020) Nyantakyi, Emmanuel Kwesi; Obiri-Yeboah, Abena; Mohammed, Ghadafi Abdullai
    The objective was to investigate partial replacement of single and mixed coloured waste glass bottle powder for cement in concrete technology. Ordinary Portland cement in concrete mix was replaced with bottle glass waste powder of 30%, 50% and 70% respectively during mixing. A mix design ratio of 1:2:4 with water-to-cement ratio of 0.6 and design strength of 20MPa was used. Concrete cubes of sizes 150mmx150mmx150mm were cast and slump tested. Compressive strength density and percentage of water absorption test for concrete curing ages at 7- and 28-days were determined respectively. The slump test results showed decreasing slump values with increasing proportions of glass bottle waste powder. Further tests on the concrete specimen showed decreased compressive strength, density and percentage of water absorption values as glass bottle waste powder in concrete increased as compared to the control concrete mix. Replacement of glass bottle powder of 30% for cement in the concrete showed an enhanced performance when compared with the other percentage ratios used as well as the control mix. The study therefore recommends a 30% glass bottle waste powder to replace cement. The study recommends a study of the replacement over a longer period to verify the properties obtained.
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    Investigating Occupational Health and Safety of Workers on Selected Construction Sites in the Sunyani Municipality, Ghana
    (Journal of Safety Engineering, 2020-08-26) Nyantakyi, Emmanuel Kwesi; Obiri-Yeboah, Abena; Obeng-Ahenkora, Nana Kwame
    The administration of Health and Safety is an issue that is significant and pivotal to all organizations across all businesses worldwide. This integrates conventional and commercial businesses, data innovation (IT), care homes, schools, higher instructive teaching, travel and relaxation among others. The construction industry in the nation has always suffered due to hazardous working conditions. Occupational Health and safety is specifically significant and vital for the construction industry. The construction industry has a global reputation for the quality of work but, however, remains one of the most dangerous industries within the country. Contractors, subcontractors and their workforce quite frequently face varied risks from hazards which could result in injuries, other illnesses and even deaths in severe instances. This study investigated occupational health and safety on selected construction sites in the Sunyani Municipality in Ghana. Three different sets of questionnaires were distributed to and interviews conducted for consultants, contractors and construction workers in the Building Construction Industry. The focus of the interviews and questionnaires included accident origins, health and safety policy and management, factors affecting health and safety and reporting schedules. The results indicated that the factors responsible for most accidents on construction sites are workforce situations and management operations. It was also revealed that lack of PPE’s, technical guidance, training, safety knowledge and fatigue could seriously affect health and safety on construction sites either as one or in combination. The study recommended the enforcement of safety protocols on all construction sites and a progressively consistent and sustainable health and safety educational campaign programmes to enhance awareness of the negative implications of lack of health and safety procedures on site.
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    Impact of urban land cover change on the garden city status and land surface temperature of Kumasi
    (Cogent Environmental Science, 2020-06-17) Mensah, Caleb; Atayi, Julia; Kabo-Bah, Amos T.
    Rapid urban expansion and development have resulted in the conversion of many natural green surfaces within cities to non-transpiring built-up surfaces, such as concrete and asphalt. These artificial urban surfaces cause substantial variation in land surface temperatures that affect the urban microclimate. Thus, there is the need to substantially quantify the extent of green cover loss within growing cities and its impact on surface temperatures. This study used LANDSAT data to spatially assess the extent of urban expansion and its effect on land surface temperature within Kumasi, Ghana. Subsequently, the results showed significant changes in the land cover, which had an effect on the observed land surface temperatures from 1986 to 2015. Generally, there was an overall increase in the built-up areas by 24.13% (55.81 km2 ) from 1986 to 2015, with a corresponding increase in the mean land surface temperature by 4.16°C. As such, there is the need for the adoption of sustainable urban planning strategies with green vegetation conservation initiatives for modern city planners. This would help reduce urban land surface temperatures while promoting clean air circulation within the city
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    Hydrologic response to climate change in the Densu River Basin in Ghana
    (Heliyon, 2020-08-11) Oti, Jonathan Opoku; Kabo-bah, Amos T.; Ofosu, Eric
    Climate change continues to pose a threat to the sustainability of water resources. Global warming can have several effects on the water resources and water demands in the Densu River Basin especially household water use and agriculture use among several others. However, the extents to which the hydrology of the Densu River Basin is will be altered in the future remains unknown. In this research, the Water Evaluation and Planning (WEAP21) system was used to study the impacts of future climate change on water resources in the Densu River Basin. Future climate data (rainfall and temperature) for the period 2051–2080 was generated from the Swedish Meteorological and Hydrological Institute's climate models (ICHEC-EC-EARTH and RCA4) for RCP4.5 scenario under CORDEX experiment. The results of the study indicate that the Densu River Basin will experience a temperature increase by 8.23% and a 17% reduction in rainfall resulting in 58.3% reduction in water resources in the area. The climate change impact analysis indicates a reduction in the river streamflow due to decrease in rainfall. It is recommended that future research on climate change adaptation for water management in the Densu River Basin should be conducted.
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    Hydrodynamic Model for Operational Forecasting in Coastal Waters of Ghana
    (Open Journal of Modelling and Simulation,, 2020-04-07) Felix, Uba; Essandoh, Eric Osei; . Nyantakyi, Emmanuel K
    The provision of economic resources to countries at the shore of Gulf of Guinea is a very important effort that has helped West Africa to develop to some extent. Taking the study area as a system it will be important to know the dynamics that occur in it to help neighouring countries predict its physical and thermodynamics states at all times. Ghana is located in West Africa and it is bordered in the south by the Gulf of Guinea or Atlantic Ocean. The objective of this research is to characterize the hydrodynamic circulation of the Gulf of Guinea areas neighouring Ghana. A 3-Dimensional hydrodynamic model was implemented in the territorial waters of Ghana using the Mod elo Hidrodinâmico, MOHID model to represent the dynamics and study the complex circulation pattern of the sea. To achieve this in an affordable computational time, nested domain approach was used to implement the hydrodynamic model in both 2 and 3-Dimensional gridded levels. The first level is a barotropic model with only tide. The nested domains of the rest of the levels are baroclinic forced with atmospheric and oceanic elements. To quantify its accuracy, the model was validated and calibrated in three stages; first, the frequency of the water level, followed by the circulation pattern and last, analysing the nature and profiles of the atmospheric and oceanic elements. The implemented model showed good agreement with the measured water surface level in the domain with mean error values not exceeding 14.00% of the measured data and with correlation factors higher than 0.80. Also, the intensity and direction of velocity observed in the current data are well represented by the model at the water surface levels with mean errors lower than 20.00% of the measured data components. The profiles obtained for both the temperature and salinity at shore show completely a straight line for salinity and also a straight line which is slightly curved at the top for the temperature profile. The vertical straight line for the salinity profile shows that at the shore the waters are not stratified vertically or they are well mixed. The slight curve at the top of the temperature graph accounts for the mixing dynamics that occur close to land or the effect of heat flux at the surface. It can be concluded that the hydrodynamic model obtained by this study is the true reflection of the territorial waters of Ghana
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    Geospatial Assessment of Land Use and Land Cover Patterns in the Black Volta Basin, Ghana
    (J Remote Sens GIS, 2020-01-06) Amproche, A. A.; Antwi, M; Kabo-Bah, A.T.
    The Black Volta Basin in Ghana has experienced some losses in its productive lands due to mining. This study assessed the Land use/cover (LULC) changes within the Basin for a period of eighteen years, and mapped current and potential mining hotspots in the Basin. The study used multispectral Landsat images for the years 2000, 2015 and 2018. Supervised classification method and Spectral Angle Mapper were used to classify and map the LULC types. Feature-based extraction method was then used to delineate mining sites along the River in the Basin. Six (6) LULC types were classified. Findings from the study revealed that four of the classified LULC experienced some form of decline between the years 2000 and 2018, except Bareland and settlements which consistently increased within the period, with Barelands recording the highest increase of 21% between 2000 and 2015 and 18% between 2015 and 2018, signaling a sharp increase in the three year period. From the feature-based extraction, 312 segments of an average area of 8.4 km of each segment were found to be mining sites from the 2018 image analysis, which is about 80% of the total Bareland in 2018. Likewise, 146 segments of an average area of 3.9 km of each segment were found to be potential mining sites. This implies that mining within the basin is threatening other LULC and hence, reclamation and restoration activities need to be intensified. The outcome of this research could facilitate technological strategies towards restoration projects within the Basin.
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    Comparison and Estimation of Four Infiltration Models
    (Open Journal of Soil Science, 2020-02-21) Atta-Darkwa, Thomas; Antwi, Eric Ofosu; Amankwah, Emmanuel
    Infiltration is an important component of the hydrological cycle. It provides soil moisture in the vadose zone to support plant growth. This study was conducted to compare the validity of four infiltration models with measured values from the double ring infiltrometer. The parameters of the four models compared were estimated using the linear regression analysis. The C.C was used to show the performance of the predictability of the models. The RMSE, MAE and MBE were employed to check the anomalies between the predicted and the observed values. The results showed that, average values of the C.C ranged from 0.9294 - 0.9852. The average values of the RMSE were 4.0033, 17.489, 11.2400 and 49.8448; MAE were 3.1341, 15.9802, 10.6525, and 61.4736; and MBE were 0.0786, 9.5755, −0.0007 and 47.0204 for Philip, Horton, Green Ampt and Kostiakov respectively for the wetland soils. Statistical results also from the Fisher’s multiple comparison test show that the mean infiltration rate estimated from the Green Ampt’s, Philip’s and Horton’s model was not significantly different (p > 0.05) from the observed. The re sults indicated that the Kostiakov’s model had the highest deviations as it overestimated the measured data in all the plots. Comparison of the statistical parameters C.C, RMSE, MAE, and MBE for the four models indicates that the Philip’s model agreed well with the measured data and therefore, performed better than the Green Ampt’s, Horton’s and Kostiakov’s models respectively in that order for Besease wetland soils. Estimation of infiltration rate by the Philip’s model is important in the design of irrigation schemes and scheduling. Therefore, in the absence of measured infiltration data, the Philip’s model could be used to produce infiltration information for inland valley bottom soils that exhibit similar characteristic as Besease wetland soils
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    BICARBONATE ANION AND TAED AS ACTIVATORS IN PEROXIDE BLEACHING OF A MECHANICAL PULP
    (CELLULOSE CHEMISTRY AND TECHNOLOGY, 2019-09) FRANCIS, RAYMOND C.; LUUKKONEN, ANTTI; ATTIOGBE, FRANCIS K.
    Earlier research demonstrated that the bicarbonate anion (HCO3 − ) activated hydrogen peroxide and made it into an effective bleaching agent for both chemical and mechanical pulps at pH ~ 8.5. The peroxide/bicarbonate treatment is designated as a PB stage. It was also observed that in PB bleaching of chemithermomechanical pulps (CTMPs), a higher initial pH resulted in more H2O2 being consumed and the achievement of a higher bleached brightness. This research focused on using Na2CO3 instead of NaHCO3 to achieve a higher pH in PB bleaching of softwood CTMP. Further activation of the H2O2 was obtained by the addition of N, N, N’, N’-tetraacetylethylenediamine (TAED). There was a high peroxide residual when 3.0% H2O2 on pulp (oven-dried or OD basis) was used in a conventional alkaline peroxide (P) stage. Sodium carbonate was added to the P stage effluent (with or without TAED), which was recycled and used to pretreat unbleached pulp. A significant increase in brightness (~3 points) was obtained when the pretreated pulp was regularly bleached with 3.0% H2O2 on pulp in a P stage
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    Barriers and opportunities for cleanliness of shared sanitation facilities in low-income settlements in Kenya
    (BMC Public Health, 2020) Simiyu, Sheillah N.; Kweyu, Raphael M.; Antwi-Agyei, Prince
    Background: The sharing of sanitation facilities is a common practice in low-income areas in sub-Saharan Africa. However, shared sanitation is currently categorized as a limited sanitation service, and may therefore not count towards meeting the global goals. These shared facilities are often the only option available for most residents in low-income settlements, and improving their cleanliness and overall management is key to reducing open defecation and risk of disease. This study sought to investigate barriers and opportunities for improved cleanliness of shared sanitation facilities in low-income settlements of Kisumu city, Kenya. Methods: Thirty-nine in-depth interviews and 11 focus group discussions were held with residents – mainly tenants and landlords – of a low-income settlement in Kisumu. Analysis followed a thematic approach to define the problem, specify the target behaviour and identify the changes needed. Results: Sanitation facilities were mainly pit latrines, typically shared among landlords and tenants. Participants singled out behavioural (poor use of the shared toilets) and social (lack of cooperation in cleaning) challenges that led to unclean shared toilets. Available opportunities for improvement included instituting clear cleaning plans, improving communication among users, and enhanced problem-solving mechanisms between landlords and tenants. These approaches could form the basis for designing intervention strategies for improving the cleanliness of shared sanitation facilities. Conclusion: The results highlight the need to focus on social aspects for improvement of cleanliness in shared sanitation facilities in low-income settlements. Through a social approach, shared sanitation facilities can be managed appropriately to provide the millions of low-income residents in Kenya an opportunity to access sanitation. This study provides further evidence on approaches for improved management of shared sanitation facilities in line with the World Health Organization’s (WHO) Joint Monitoring Program’s (JMP) recommendation for high quality shared facilities.
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    Assessment of physicochemical properties of Besease wetland soils, Ghana
    (African Journal of Agricultural Research, 2020) Atta-Darkwa, Thomas; Asomaning, Samuel Kwasi; Agbeshie, Alex Amerh
    The shallow and erodible soils of low fertility uplands have led to farmers extending their cultivable areas to wetlands for optimal crop production since these systems have the potential for exploitation in the dry season. To ensure its sustainable use, the physicochemical and the hydrological characteristics of the valley bottom should be ascertained. Studies were conducted to assess the suitability of wetlands for crop production by analysing the physicochemical properties of Besease wetland soils. Soil samples were collected from specific sites and profile pits for physical and chemical analysis in the laboratory. Field experiments were also conducted for soil physical properties. Soil textural analysis revealed that the average texture of the Besease inland valley was sandy loam with the distribution of sand, silt and clay as 55.42, 35.04 and 9.50%, respectively. Bulk density and moisture content on the field increased with depth in all profiles. Results of hydraulic conductivity using the mini disk infiltrometer ranged from 2 to 88.3 cm/day. The infiltration rate on the studied wetland ranged from 0.02 to 0.78 cm/min. The pH, OC, TN and CEC of the soil profile distribution for site P11-P14 obtained ranged from 6.9-4.6, 4.69-0.19%, 0.2-0.01%, 9- 2.6 meq/100 g down the horizon respectively. The study unraveled a sustained plant nutrient availability and elongation of water level ponding which will result in increased water storage under rice cultivation in the studied wetland.
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    Assessing the potential health impact of selected heavy metals that pollute lake amponsah in Bibiani, Western North region, Ghana
    (Scientific African, 2020) Attiogbe, Francis K.; Mohammed, Abdul Rahim; Kingslove, Quarm
    Gold mining contributes significantly to social, economic, and infrastructural development in Ghana. Apart from these benefits, mining activities have negative impacts on the environment as well as the health of fringe communities who depend on the environmental resources for survival. However, despite the increase in small scale mining in the Bibiani Anhwiaso Bekwai Municipal, the extent to which these activities have impacted on the quality of the Amponsah lake is largely unknown. This study, therefore, assessed whether or not the activities of small- scale miners have impacted the quality of the Amponsah lake as well as the health of the people living in the fringe communities who depend on it for survival. The study used qualitative and quantitative data obtained from the laboratory analysis of water samples as well as the thoughts and opinions of occupants of the fringe communities to achieve the objectives of the study. Findings showed that aside total suspended solids, all the physical parameters assessed were below the Ghana Environmental Protection Agency standards. The mean recorded values for pH, temperature, dissolved oxygen, conductivity, total dissolved solids, and total suspended solids were 7.20, 29 °C, 4.80 mg/cm, 383.00 μS/cm, 185 ml/l and 132.40 mg/l respectively. Also, mean concentrations of 0.0053 mg/l, 0.3110 mg/l, 0.0372, and 0.0440 mg/l were recorded for Hg, As, Cd, and Zn respectively with the concentration of zinc only falling below the Ghana Environmental Protection Agency standards. Further, human activities such as small-scale mining, discharge of waste from nearby communities as well as leachate from a dumping site, are the major contributing factors causing pollution in the lake. Mercury source in Lake Amponsah could be through activities of small- scale miners operating around the lake over the years. The unusually high concentration of As could be likely due to the geology of Bibiani. In conclusion, the physicochemical characteristics of the Lake Amponsah have been compromised pointing to a polluted status except for Zn and total suspended solids.
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    Antimicrobial and coagulation potential of Moringa oleifera seed powder coupled with sand filtration for treatment of bath wastewater from public senior high schools in Ghana
    (Heliyon, 2020) Ntibrey, Richard Agbo Kwabena; Kuranchie, Francis Atta; Gyasi, Samuel Fosu
    The use of natural plant extracts for treatment of water in some parts of the world has been recorded throughout human history. An example is the use of Moringa oleifera in water purification due to its coagulation properties. However, the efficiency of the treatment systems largely depends on the design of the system and its operation. The aim of this study was to investigate the efficiency of Moringa oleifera seed powder coupled with sand filtration in treating greywater from public senior high schools in the Bolgatanga Municipality and Kasena Nankana West District in the Upper East Region of Ghana. Microbial and physico-chemical properties of greywater collected monthly from the senior high schools was analyzed. Moringa oleifera seed powder was added to raw greywater and then filtered through a sand filter bed. Physico-chemical and microbial parameters of the treated greywater were then analyzed. Mean turbidity, TDS, TSS, T. phosphate and T. nitrogen of the raw greywater was 312.5 76.58 NTU, 445.6 86.77 mg/L, 160.0 28.68 mg/L, 89.3 7.76 mg/L and 30.19 3.63 mg/L respectively whiles average BOD, COD, E. coli and Total coliform were 1032.5 252.40 mg/L, 1736.0 431.59 mg/L, 84.75 x 106 94.01 x 106 N/100ml and 184.25 x 10s 181 x 106 N/100ml respectively. After treatment, there was percentage reduction in turbidity (98.14%), TDS (72.7%), TSS (98.9%), T. phosphate (75.64%), T. nitrogen (43.11%), Total coliform and E. coli (>99%) were recorded. Turbidity was 0.1 NTU and did not meet the WHO standard for drinking water but T. hardness, E. coli and pH was in line with the WHO limit for drinking water. However, BOD increased, and this could be attributed to the significant protein content in the seed of Moringa oleifera. Moringa oleifera seed powder coupled with sand filtration demonstrated the antimicrobial and coagulative potential as turbidity and E. coli of the raw bath greywater from the senior high schools reduced by >98% and >99.99% respectively after treatment
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    Urban planning and public policy responses to the management of COVID-19 in Ghana
    (CITIES & HEALTH, 2021) Anaafo, David; Owusu-Addo, Ebenezer; Taky, Stephen Appiah
    The global COVID-19 pandemic, with its associated issues of isolation, enhanced hygiene practices and contact tracing brought up a number of issues to the public domain, many of which bordered on the nexus between urban planning and public health. This paper sets out to examine how new ideas concerning the linkages between urban planning and public health revealed by the COVID-19 pandemic can be integrated into practice, moving forward; and how we might leverage on the crisis to build more just, healthier and liveable cities. Through a review of the literature on public policy responses to pandemics, it is observed that the current urban planning system in Ghana leaves so many people behind and exposes the lives of many to current and future disease pandemics. We propose an agenda for transformation which revolves around the co-evolution and co-creation of new forms of societal values that are less materialistic and individualistic but rather more egalitarian.
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    COVID-19 in Africa: rethinking the tools to manage future pandemics
    (African Health Sciences, 2021) Emahi, Ismaila; Watts, Mimmie CNC; Azibere, Samuel
    Corona virus disease 2019 (COVID-19) remains an incurable, progressive pneumonia-like illness characterized by fever, dry cough, fatigue, and headache during its early stages. COVID-19 has ultimately resulted in mortality in at least 2 million people worldwide. Millions of people globally have already been affected by this disease, and the numbers are expected to increase, perhaps until an effective cure or vaccine is identified. Although Africa was initially purported by the World Health Organization (WHO) to be severely hit by the pandemic, Africa recorded the least number of cases during the first wave, with lowest rates of infections, compared to Asia, Europe, and the Americas. This statistic might be attributed to the low testing capacity, existing public health awareness and lessons learnt during Ebola epidemic. Nonetheless, the relatively low rate of infection should be an opportunity for Africa to be better prepared to overcome this and future epidemics. In this paper, the authors provide insights into the dynamics and transmission of the severe acute respiratory syndrome corona virus (SARS-CoV-2) during the first wave of the pandemic; possible explanations into the relatively low rates of infection recorded in Africa; with recommendations for Africa to continue to fight Covid-19; and position itself to effectively manage future pandemics.
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    Integration of GIS and F-Hydra Model for Aquifer Vulnerability Monitoring in the Afram Plains, Ghana
    (Journal of Geoscience and Environment Protection, 2021) Agyare, Asante; Kabo-Bah, Amos Tiereyangn; Bayel, Bernard Trumah
    Aquifer vulnerability is a critical issue across the entire globe due to the de pletion of groundwater and escalation of pollution levels, which poses a det rimental effect on the natural environment. To ascertain this contamination risk, an extensive study has been conducted to assess the aquifer vulnerability by using the F-hydra model. This paper presents the vulnerability technique for the theory and application of flow accumulation, land-use and hydraulic conductivity. The model was applied to a shallow aquifer in eastern Ghana’s Volta River Basin, with the results being compared to the standardised DRASTIC model. The model follows the aquifer vulnerability assessment concept of the source pathway receptor where flow accumulation represents the ponding areas with downward percolation of contaminant to the water table, land-use represents the human activities at the land surface, and hy draulic conductivity represents the driving force leading to the movement of contaminant. The results reveal that the moderate vulnerability region covers 51.55% (2598.12 km2 ) of the entire area. The high and low vulnerability re gions cover a significant percentage of the area 1.13% (56.52 km2 ) and 47.32% (2384.93 km2 ), respectively. The final vulnerability index was largely influ enced by the removal of the hydraulic conductivity and land-use parameters. The model was validated with nitrate concentration in drilled wells in the study area. The maps produced in this study could be utilised as a guide to vulnerability by policymakers, groundwater manager and planners aimed at preserving the integrity of this vulnerable resource
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    Increase water harvesting in Africa
    (Nature, 2015) Rockström, Johan; Falkenmark, Malin
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    How Much Will Safe Sanitation for all Cost? Evidence from Five Cities
    (Environ. Sci. Technol., 2020) Delaire, Caroline; Peletz, Rachel; Haji, Salim
    : Global sustainable development goals call for universal access to safely managed sanitation by 2030. Here, we demonstrate methods to estimate the financial requirements for meeting this commitment in urban settings of low-income countries. Our methods considered two financial requirements: (i) the subsidies needed to bridge the gap between the willingness-to-pay of low-income households and actual market prices of toilets and emptying services and (ii) the amounts needed to expand the municipal waste management infrastructure for unserved populations. We applied our methods in five cities− Kisumu, Malindi, Nakuru in Kenya; Kumasi in Ghana; and Rangpur in Bangladesh and compared three to five sanitation approaches in each city. We collected detailed cost data on the sanitation infrastructure, products, and services from 76 key informants across the five cities, and we surveyed a total of 2381 low-income households to estimate willingness-to-pay. We found that the total financial requirements for achieving universal sanitation in the next 10 years and their breakdown between household subsidies and municipal infrastructure varied greatly between sanitation approaches. Across our study cities, sewerage was the costliest approach (total financial requirements of 16−24 USD/person/year), followed by container-based sanitation (10−17 USD/person/year), onsite sanitation (2−14 USD/person/year), and mini-sewers connecting several toilets to communal septic tanks (3−5 USD/person/year). Further applications of our methods can guide sanitation planning in other cities.