College of Engineering

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    Adoption and Effects of Climate Change Adaptation, and Land Use Decision of Smallholders Farmers in the Saline Area of Sine-Saloum, Fimela Senegal
    (2023-07) Thiam, Habibatou Ibrahima
    Soil salinity expansion is one of the most severe land degradation issues confronting farmers in Senegal, particularly in coastal areas such as Fimela. With sea level rise, temperature rise, and rainfall decrease, soil salinity is increasing significantly. It has a negative impact on crop yields and farmers' livelihoods. Farmers developed land use adaptation strategies to deal with soil salinity. Nonetheless, despite adaptations, some farmers continue to complain about the negative impact of soil salinity on their outcomes. Then, this study investigates farmers' adaptation, the different factors that influence it, its implications for smallholder farmers' livelihoods, and farmers' perception of soil salinity and its impact. Data from face-to-face interviews of 288 households using the Krejci and Morgan’s formula and GPS coordinates of households and each of their farms was collected. An agent-based model was used to understand land use adaptation to soil salinity expansion by considering farmers' perceptions of soil salinity expansion under climate change for simulation. A sub-model of household decisions, crop yield, and perception of soil salinity was developed and incorporated into the model. Three scenarios were considered to simulate the interaction between household agents and landscape agents over 25 years. Farmers' adoption is influenced by their assets and sociopsychological factors like threat assessment, coping assessment, and subjective norms. Farmers in Fimela do not have maladaptation thinking that may break their willingness to adopt strategies to cope with soil salinity. The ESR model shows that farmers' adoption of strategies to cope with soil salinity has a positive impact on groundnut yields and a negative influence on food security but has no significant effect on their millet yields. These findings have been validated by the simulation results, which show that the yield difference between farmers who perceive soil salinity expansion and those who do not is significant for groundnut but not millet over 25 years. As a result, it is critical to base policies in combating soil salinity effects on providing better methods of soil salinity adaptation strategies through scientific research. Policies should support a few pilot farmers in these precise and effective strategies to trigger other farmers to follow through the village and social influence by the farmer-to-farmer approach to enable farmers access and appropriation of these new methods.
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    Agricultural Land Use Change in the Lowlands of Southern Mali under Climate Variability
    (KNUST, 2023-07) Traore, Alou
    This research investigated agricultural land use change in the lowlands of Southern Mali under climate variability. Four supervised classification techniques, Classification and Regression Tree (CART), Support Vector Machine (SVM), Random Forest (RF) and Gradient Tree Boosting (GTB) in Google Earth Engine (GEE), were used for the image classification. An integrated Cellular Automata-Artificial Neural-Network (CA-ANN) within the MOLUSCE plugin of QGIS was used for future Land Use and Land Cover prediction. The Mann-Kendall test, Sen’s slope, Pettit-test and change-point detection analyse were applied for climate variability assessment. Monthly rainfall and mean temperature extending over a period of 61 years (1960–2020) recorded at Sikasso District were analysed. Annual rainfall varied between 800 mm to 1600 mm and annual mean temperature ranged between 25 oC to 28 oC. Seasonal rainfall ranged between 37-387 mm, March-April-May (MAM), 400-1030 mm, June-July-August (JJA), 77-577 mm September-October-November (SON) and 0-45 mm for December-January-February (DJF). Mean seasonal temperature ranged from 29 oC to 32 oC (MAM), 26.5 oC to 28.5 (JJA) oC and 26 oC to 28 oC (SON). Annual and seasonal rainfall trends increased slightly. Temperature showed a significant increase in both annual and seasonal trends. Out of 395 respondents, 79 % were of the view that annual rainfall decreased while 83 % reported mean temperature increased. Again, respondents perceived late onset rainfall (97 %), early cessation of rainfall (96 %), increased in drought (83 %) and flooding (96 %). Also, 43 % of respondents adopted new varieties to cope with climate variability. The findings showed that physical and socioeconomic driving forces had impact on terrain patterns. Over the past three decades, the study revealed that apart from cropland area which increased from 43.81 % to 52.75 %, the size of the other land uses decreased, forest cover (19.93 % - 13.93 %) shrubs (16 % - 14 %), and streams (6 % - 4 %). However, the forecast for the 2020 to 2030 predicted an increasing trend in forest cover and decreasing trend in agricultural land in the study area due to the ongoing afforestation projects. The study demonstrates the need to reinforce regional land management policies and programmes.
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    Analysis and modelling of suspended sediment concentration of rivers in catchments experiencing land cover degradation
    (October, 2019) Boakye, Ebenezer
    Amongst the issues threatening water security and sustainability is the increasing rate of river sedimentation. Variations in catchment sediment yield results from the variations in its controlling factors such as land use/cover characteristics. Thus, it is crucial that this factor is monitored and managed to ensure sustainability of the resource. However, existing models (statistical) have failed to explore the influence of the land use types. Hence, land cover effect and its associated modifications on the variations in suspended sediment concentration have not been empirically quantified, especially for catchment with heterogeneous land cover classes. In view of this, this research answers the question “To what extent does land use/cover characteristics influence the variations in catchment suspended sediment yield?” The following specific objectives were addressed: (1) to assess the trend and extent of land use /cover changes in the Pra River Basin and their driving forces; (2) to assess the variations in suspended sediment yield of the catchment; (3) to determine the sediment generating areas of the catchment and (4) to assess the relative importance of land use types on the variation of suspended sediment yield and to forecast same. Remote sensing and Geographic Information System techniques, field measurement, data collection and laboratory analysis, and statistical techniques such as Analysis of Variance, multiple regression and correlation analysis were employed for the study. Results reveal that between 1986 and 2018, the Pra River basin had suffered severe land cover degradation resulting from anthropogenic influence. Land use conversion occurred generally from closed and open forest to farmlands, settlement and mining. However, the rate, extent and trend of conversions differed significantly across it sub-basins. Sediment yield of the basin is very high ranging between 13.29 and 215.02 tkm-2yr-1, and differs significantly (p < 0.05) with respect to the contributing drainage basins. Erosion map showed that about 21.3% of the basin comes under severe and very severe erosion risk category. Soil erosion rate varied with land use types in a decreasing order from Mining to Settlement, Farmland/grassland, Open forest and Closed forest. Lower Ofin, Anum, Birim, Twifu Praso, Upper Ofin and Oda sub-basins were identified to be susceptible to high erosion. Model accuracy increased from 60.2% to 76.7% when land cover types were included as predictor variable in the suspended sediment concentration model. This indicates that land cover characteristics play a significant role in explaining the variations in catchment suspended sediment yield. The study recommends that immediate conservation measures and policy implementation must be put in place to restore the ecological integrity of the degraded sub-basins. The need to form district ecological or environmental task force involving officials of water, environment and security agents can be useful in handling respective sub-basin’s environmental threats. This will preserve the water resources for sustainable use.
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    Artistic and Educational Values of Kusakɔ Kɔ Initiation Rites of Avatime in the Volta Region
    (2015-05-22) Dedume, Victor
    The woman is a significant figure in the development of Avatime community. People of Avatime recognize and value the role of women in society and therefore mark the transition of a female from girlhood to womanhood. The problem is that many artistic and educational values are embedded in the celebration of this transition called kusak) k) initiation rites, yet they have not been described, discussed or documented, therefore they could be lost. Moreover, appreciable amounts of vital information embodied in kusak) k) initiation rites are not being taught in the schools of Avatime. Sadly, the rich cultural heritage embodied in the artistic and educational values which should be preserved have not been documented to put the area in the spotlight of the world. This research adopted a qualitative approach, specifically ethnography, to collect data through observation and interviews. The main findings are that, the Avatimes mark the passage of their girls into womanhood by performing series of rituals known as kusak) k). Numerous artistic and educational values are evident in the rituals. Artistic values are demonstrated in the use of ritualized visual and performing arts. Educationally, the performing arts serve as symbols of identity and means of communication. Recommendations were that there should be collaboration between the pastors and the custodians of Avatime traditional area to erase the notion that there are sacrilegious beliefs and superstitions embedded in kusak) k) rites. It is also recommended that more group ritual activities be encouraged and done once a year for school going girls and workers to participate during school holidays and weekend respectively. Control measures should be instituted to curb promiscuity in the area. Finally, it is highly recommended that this document should be incorporated in the Art Education Curriculum to put the values of kusak) k) in the spotlight of the world.
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    Assessing Urban Flood Risks under Changing Climate and Land Use in Abidjan District, South Cote d’Ivoire
    (APRIL, 2016) Danumah, Jean Homian
    Climate change has become one of the global environmental issues more visible in recent decades. Flooding is one of the natural disasters that combine with climate change to create effects and cause some of the most destructive damages in Cote d’Ivoire. The District of Abidjan located in the south of Cote d'Ivoire which is subjected to heavy rainfall, rapid population growth and uncontrolled urbanisation is not an exception to the problem of flood risk. The aim of this study was to identify, map and model areas of flood risk to facilitate decision making for better land use planning under changing climate in this District. The maximum likelihood classification algorithm and post-classification change detection procedures were used in this study. The spatio-temporal land use/ land cover change in relation to urbanisation sprawl was assessed based on a series of Landsat images for 1990, 2002 and 2014. Statistical methods were also used to characterise and determine hydro-climatic drivers of flood. LARS-WG model was used to generate future scenario based on HadCM3 model and SRA1B emissions and in rclimdex model, ten (10) rainfall indices were calculated. LARS-WG and rclimdex were used to determine and analyse trends of rainfall and temperature under present and future climatic conditions. Analytic Hierarchy Process (AHP) method as a multi-criteria analysis allows the integration of several elements under two criteria: hazard and vulnerability for flood risk assessment and mapping. Flood Hazard Index (FHI) model was carried out to determine flood prone areas by combining rational and statistical methods. The results revealed urban area expansion (15%) as a major land use change for the period 1990-2014. However, there was an important increase in urban area between 2002 and 2014, compared to 1990-2002. Regarding future weather, LARS-WG statistical results showed that, temperature will increase from 0.32°C to 2.54°C for the period 2011-2100. Also, rainfall in the same period will increase from 4 %, to 10 %. Results of rclimdex through ten (10) rainfall indices and comparison between observed and future indices indicated an increased trend of some rainfall indices: Consecutive wet Days (CWD) and number of heavy rainfall days above 10mm (R10) from 2011 to 2100. AHP flood risk map showed that areas under high and very high flood risk covers 34% of the study area while Flood Hazard Index (FHI) model revealed that about 25.09 % of the study area were within the high FHI areas. Both results showed that eight out of thirteen (8/13) municipalities of Abidjan District are within high and very high flood risk areas. Therefore, there is a need for decision makers to call for optimal design of technical solutions and an effective preparedness strategy to be developed for future flood occurrence within Abidjan District (South of Cote d’Ivoire).
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    Bayesian analysis of the incidence if HIV/AIDS in Upper East Region
    (2009-07-30) Ali, Clement Ayarebillah
    Development and growth cannot be experienced in any part of the world without good education. Basic education is one of the effective investments in improving economics, reducing illiteracy, creating self-reliant and healthy society.
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    Characterization of Glucoamylase Produced by Aspergillus niger and Rhizopus sp.
    (2015-04-20) Nyamful, Andrew
    Amylase enzymes are important enzymes employed in starch processing industries for hydrolysis of polysaccharides into simple sugars. Microorganisms including a number of fungal species have been used to produce amylases more economically than from other sources. Glucoamylase (C3009H4570N782O1012S13) is an exoenzyme that removes glucose units consecutively from the nonreducing ends of starch and oligosaccharides. The enzyme also cleaves α-1, 6- and α-1, 3-bonds but at a slower action. Glucoamylase is used in processed-food industry, fermentation technology, textile and paper industries. In this study, four native fungal isolates, Aspergillus niger, Aspergillus flavus, Rhizopus species and Fusarium oxysporum and the potential of five solid substrates, wheat bran, rice bran, groundnut pod, maize bran and cocoa pod for glucoamylase production were investigated using Solid-State Fermentation process. Isolates of Aspergillus niger and Rhizopus species on wheat bran as substrate at spore concentrations of 1 x 107 per ml produced the highest enzyme activities under optimum growth conditions. Glucoamylase production was found to be affected by temperature, pH, incubation period, nature of substrate and the kind of microorganism used. Glucoamylase production by Aspergillus niger was found to be affected by nitrogen. Glucoamylase produced by Aspergillus niger yielded maximum enzyme activity of 6.66 U/ml in 18 hours of incubation period at a temperature of 40ºC, nitrogen concentration of 0.2 g/l and at pH 5.0. Similarly, glucoamylase produced by Rhizopus species gave maximum enzyme activity of 4.44 U/ml in 18 hours of incubation period at a temperature of 40ºC and pH 4.5. Molecular weights of proteins in culture filtrates were determined by SDS-PAGE. Proteins with molecular weights 61.48, 29.68, 21.06 and 12.33 KDa were identified from culture filtrates of Aspergillus niger and proteins with molecular weights 96.40, 65.56, 51.80, 29.05 and vii 19.75 KDa were found from culture filtrates of Rhizopus species. Kinetic studies using Hanes-Woolf’s plot and starch as substrate gave Kmax = 0.0009548 g/l and Vmax = 2.387 g/l.min for enzyme produced by Aspergillus niger and Kmax = 0.0007443 g/l and Vmax = 2.481 g/l.min for enzyme produced by Rhizopus species
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    Comparative studies of the electricity generation, desalination and wastewater treatment performance of the Three-Chamber and newly developed Five Chamber Microbial Desalination Cells
    (2021-07-09) Imoro, Abubakari Zarouk; ;
    Poor wastewater treatment and limited potable water supply in the country are problems that require sustainable solutions. Available technologies to solve these problems are expensive especially to a developing country like Ghana. A recently developed technology, Microbial Desalination Cell (MDC) is considered a less expensive alternative to conventional wastewater treatment and desalination technologies. In MDCs, wastewater treatment occurs in the anode chamber and desalination in the desalination chamber. A third chamber, the cathode chamber is present to create a potential difference across the anode chamber and itself for electricity production. One setback of MDC systems however is that, most operate with chemical oxidants and buffers which can make this technology expensive. Thus, this research work sought to build MDCs which operate on alternative non-chemical oxidants sources and also, MDCs which are able to buffer electrolytes without the use of chemical buffers. Another objective of this study was to investigate the effects of rhamnolipid on MDCs electricity generation, desalination and wastewater treatment performances. The interactive effect of rhamnolipid and stirring on a five-chambered MDC was also investigated and ion exchange membranes of selected MDCs examined for the occurrence of fouled layers. A comparison between the electricity generation, desalination and wastewater treatment performances of three-chamber MDCs operating on different electron acceptor sources showed that, the threechamber chemical catholyte (3 C C) MDC performed better than the three-chamber water catholyte (3 W C) MDC and three-chamber plant-supported (3 P C) MDC. The 3 C C MDC produced the highest peak voltage of 282.91± 0.09 mV, coulombic efficiency of 78.61% and could desalinate 46.66% of saltwater. Its power (0.35 ± 0.10 W/m3 ) and current (1.24 ± 0.35 A/m3 ) densities were also the highest amongst the three-chambered MDCs. It produced a 42.81% COD reduction, 1.14% nitrate reduction and a 10.71% phosphorus reduction. On the other hand, the 3 P C MDC produced the least performance. The highest voltage recorded from it was 193.99 ± 0.80 mV. The 3 P C MDC could desalinate 23.34% of saltwater, produce 0.25 ± 0.06 W/m3 of power, 1.09 ± 0.11 A/m3 of current density with coulombic efficiency (CE) of 10.03%. It achieved a percentage COD reduction of 41.79%, highest percentage nitrate removal of 1.05% and phosphorus reduction of 9.97%. Apparently, the pH stabilization ability of neutralization chambers was lower than that of potassium phosphate buffer they were compared to. For instance, with the neutralization chamber, pH-change in the anolyte of the five-chamber chemical catholyte (5 C C) MDC was 1.66 ± 0.11 whiles pH change in the 3 C C MDC was 1.52 ± 0.15. Nonetheless, the 5 C C MDC produced a comparatively higher voltage of 343.57 ± 0.25 mV, percentage desalination of 50.01%, but a lower CE of 25.20%. Its power and current densities were 0.62 2 ± 0.13 W/m3 and 1.61 ± 0.21 A/m3 respectively. It was able to reduce COD concentration by 63.42%, nitrate concentration by 2.12% and phosphorus by 3.85%. The supply of rhamnolipids to anolytes of the five-chamber MDCs increased their performances. Voltage production of the 5 C C MDC increased from 343.57 ± 0.25 mV to 630.60 ± 1.44 mV, percentage desalination from 50.01% to 67.63% and COD, from 63.42% to 72.78%. In the case of the five-chamber water catholyte (5 W C) MDC, its voltage increased from 164.5 ± 0.11 to 623.7 ± 1.32 mV, percentage desalination from 43.74% to 63.21% and percentage COD reduction from 48.74% to 65.31%. Stirring (60 rpm) of water catholyte alone, could increase the percentage desalination of 5 W C MDC from 48.74% to 65.29% and voltage production from 164.5 ± 0.11 to 567.27 ± 18.06 mV. However, the interaction effect of rhamnolipid and stirring on the performance of the 5 W C MDC was insignificant. Analysis of membranes of the 5 W C MDC showed that, the membranes were fouled on both sides. And a comparison between the degree of fouling on cation exchange membranes (CEMs) of the 5 C C MDC and 5 W C MDCs revealed that, the CEM of the 5 C C MDC was more fouled though used for a lesser period of time. Having assessed the core performances and material requirements of MDCs investigated in this study, the 5 W C MDC was found to be the ideal MDC for possible future use in Ghana. Thus, the 5 W C MDC when integrated with conventional wastewater treatment and desalination technologies can aid these technologies achieve higher treatment qualities aside the additional benefit of ‗free‘ electricity the 5 W C MDC can provide.
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    Comparative studies of the Electricity Generation, Desalination and WastewaterTreatment Performance of the Three-Chamber and Newly Developed Five Chamber Microbial Desalination Cells
    (NOVEMBER, 2019) A Imoro, Abubakari Zarouk; ;
    Poor wastewater treatment and limited potable water supply in the country are problems that require sustainable solutions. Available technologies to solve these problems are expensive especially to a developing country like Ghana. A recently developed technology, Microbial Desalination Cell (MDC) is considered a less expensive alternative to conventional wastewater treatment and desalination technologies. In MDCs, wastewater treatment occurs in the anode chamber and desalination in the desalination chamber. A third chamber, the cathode chamber is present to create a potential difference across the anode chamber and itself for electricity production. One setback of MDC systems however is that, most operate with chemical oxidants and buffers which can make this technology expensive. Thus, this research work sought to build MDCs which operate on alternative non-chemical oxidants sources and also, MDCs which are able to buffer electrolytes without the use of chemical buffers. Another objective of this study was to investigate the effects of rhamnolipid on MDCs electricity generation, desalination and wastewater treatment performances. The interactive effect of rhamnolipid and stirring on a five-chambered MDC was also investigated and ion exchange membranes of selected MDCs examined for the occurrence of fouled layers. A comparison between the electricity generation, desalination and wastewater treatment performances of three-chamber MDCs operating on different electron acceptor sources showed that, the threechamber chemical catholyte (3 C C) MDC performed better than the three-chamber water catholyte (3 W C) MDC and three-chamber plant-supported (3 P C) MDC. The 3 C C MDC produced the highest peak voltage of 282.91± 0.09 mV, coulombic efficiency of 78.61% and could desalinate 46.66% of saltwater. Its power (0.35 ± 0.10 W/m3) and current (1.24 ± 0.35 A/m3) densities were also the highest amongst the three-chambered MDCs. It produced a 42.81% COD reduction, 1.14% nitrate reduction and a 10.71% phosphorus reduction. On the other hand, the 3 P C MDC produced the least performance. The highest voltage recorded from it was 193.99 ± 0.80 mV. The 3 P C MDC could desalinate 23.34% of saltwater, produce 0.25 ± 0.06 W/m3 of power, 1.09 ± 0.11 A/m3 of current density with coulombic efficiency (CE) of 10.03%. It achieved a percentage COD reduction of 41.79%, highest percentage nitrate removal of 1.05% and phosphorus reduction of 9.97%. Apparently, the pH stabilization ability of neutralization chambers was lower than that of potassium phosphate buffer they were compared to. For instance, with the neutralization chamber, pH-change in the anolyte of the five-chamber chemical catholyte (5 C C) MDC was 1.66 ± 0.11 whiles pH change in the 3 C C MDC was 1.52 ± 0.15. Nonetheless, the 5 C C MDC produced a comparatively higher voltage of 343.57 ± 0.25 mV, percentage desalination of 50.01%, but a lower CE of 25.20%. Its power and current densities were 0.62 2 ± 0.13 W/m3 and 1.61 ± 0.21 A/m3 respectively. It was able to reduce COD concentration by 63.42%, nitrate concentration by 2.12% and phosphorus by 3.85%. The supply of rhamnolipids to anolytes of the five-chamber MDCs increased their performances. Voltage production of the 5 C C MDC increased from 343.57 ± 0.25 mV to 630.60 ± 1.44 mV, percentage desalination from 50.01% tov 67.63% and COD, from 63.42% to 72.78%. In the case of the five-chamber water catholyte (5 W C) MDC, its voltage increased from 164.5 ± 0.11 to 623.7 ± 1.32 mV, percentage desalination from 43.74% to 63.21% and percentage COD reduction from 48.74% to 65.31%. Stirring (60 rpm) of water catholyte alone, could increase the percentage desalination of 5 W C MDC from 48.74% to 65.29% and voltage production from 164.5 ± 0.11 to 567.27 ± 18.06 mV. However, the interaction effect of rhamnolipid and stirring on the performance of the 5 W C MDC was insignificant. Analysis of membranes of the 5 W C MDC showed that, the membranes were fouled on both sides. And a comparison between the degree of fouling on cation exchange membranes (CEMs) of the 5 C C MDC and 5 W C MDCs revealed that, the CEM of the 5 C C MDC was more fouled though used for a lesser period of time. Having assessed the core performances and material requirements of MDCs investigated in this study, the 5 W C MDC was found to be the ideal MDC for possible future use in Ghana. Thus, the 5 W C MDC when integrated with conventional wastewater treatment and desalination technologies can aid these technologies achieve higher treatment qualities aside the additional benefit of ‗free‘ electricity the 5 W C MDC can provide.
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    Composting of abattoir waste and river reed: effect of feedstock and aeration mechanism on process efficiency
    (2015-04-22) George, Nana Kwesi Rockson
    Few successful composting facilities exist in Ghanaand there is limited information and experience in composting abattoir waste and river reed. These wastes are deemed to be potentially suitable for composting but not much has been reported on the composting dynamics when they are composted with different amendment materials and aeration mechanisms. Therefore, this research sought to investigate opportunities that exist for compostingin Ghana based on experiences of currently and previously operational composting facilities in Ghana and evaluate the effect of feedstock formulation, turning frequency, and aeration mechanisms on process efficiency and nutrient quality during windrow composting of abattoir waste and river reed. The state of composting facilities in Ghana was assessed through questionnaires and interviews with managersof such facilities. Two composting experiments were undertaken. The first one was conducted utilizing abattoir waste as the common substrate with source separated market/commercial waste, cocoa pod husk, corn cob and straw, yard trimming and sawmill wood shavings waste as other feedstock materials in the formulation of different composting piles. The second experiment was conducted to assess the effect of four aeration mechanisms on the composting process under an already existing formulated feedstock compositions using river reed (as main substrate), cocoa seed husk, poultry manure, clay soil, cow dung and banana waste. Parameters monitored in the piles include: Temperature, Moisture Content, Organic Matter, pH, Electrical Conductivity, Total Carbon and Total Nitrogen, Macro-nutrients (N, P, K, Mg and Ca) and heavy metals (Pb, Cd, Cu, Zn, Ni, and Cr). It was found that private agro-based facilities were the only operational composting facilities at the time of the study. Opportunities exist for investigating passive aeration mechanisms in some of iv these facilities to reduce the cost mainly due to the use of mechanical turning equipment. Analyses of physicochemical parameters confirm that feedstock composition or turning frequency had significant effect on physicochemical parameters studied. Final C/N ratio of the abattoirwaste compost ranged from 17.03 - 20.09, with no significant difference between the treatments and the interaction of feedstock and turning frequency. Organic matter degradation was influenced by both feedstock composition and turning frequency; difference in degradation data was also observed when fitted to afirst or zero order kinetics, with co-efficient of correlation (r) > 0.918. Analysis on composting of river reed, however, revealed that the kinetics of degradation could be represented by a first order rate equation. Also, findings from the studysuggest that compost maturity should be assessed by measuring two or more compostparameters, and that parameters of compost maturity need to satisfy the following threshold values: NH4 + /NO3 - ratio < 3.5, C/N ratio < 15; stable OM Loss, Temperature < 50 0 C). Passive composting showed comparable characteristics with mechanically aerated systems from this study. Multi-regression equationswere produced to predict nutrient (T, P, K) levels during composting using physicochemical parameters that are easy to measure.
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    Concentrating Solar Power in East Africa: Site Selection and Potential Assessment
    (2016-10-24) Ramde, Emmanuel Wendsongre
    The Economic Community of West African States (ECOWAS) which is a regional group of fifteen countries has some of the lowest modern energy consumption rate in the world. Concentrating Solar Power (CSP) could be an alternative renewable energy option for increasing access to electricity, for diversifying sources of energy and for reducing oil bill in the region...
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    Crash prediction models and risk factors for two-lane urban roadways
    (2013-05-26) Adams, Charles Anum
    Ghana's road network has claimed over twenty thousand lives in the last decade. More than ten thousand person suffer various degree of injuries that require medical attention annually since year 2000...
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    Crops-Livestock Integration as a Resilience Strategy to Climate Change in Burkina Faso
    (2023-07) Sanou, Charles Lamoussa
    This study titled addressed a topical issue of climate change and its impacts on farmers' livelihoods and the role that an integrated crop-livestock system can play in building resilient farmers and agricultural systems. The research first of all analysed historical climate (rainfall, minimum and maximum temperature) trends across three climatic zones Sudan (Dano), Sudan-Sahel (Niou) and Sahel (Dori)) at annual, seasonal and decadal scales. Climates indices computation was done using the package ClimPACT2 GUI in R software. Annual and seasonal climate were compared using the independent t-test. Decadal climate indices were subjected to a Principal Component Analysis (PCA). The research also analysed the susceptibility or sensibility of crop production and livestock health to climate change. Thirdly, the research developed and/or updated measurement tool known as Crop-Livestock Integration (CLI) indicators for a holistic characterisation of integrated croplivestock system. These indicators were developed based on the information from 589 farmers’ households and secondary data. Above ground, data were collected from 4,733 trees over a total land area of 243.2 ha (80.1 ha, 78.8 ha and 84.3 ha in Sudan, Sudan-Sahel and Sahel zones, respectively). Due to the Sahel zone's insecurity, soil data could be collected only within Sudan and Sudan-Sahel zones. In total, 120 composite soil samples were collected for this purpose and 240 other samples for soil bulk density determination. Results revealed changes in climate conditions, more pronounced in temperature variations than in rainfall. In the Sudan-Sahel and Sahel zones, a re-wetting trends was observed over the last decade supporting the re-greening hypothesis of the Sahel. Despite some positive effects of the climate indices, crop failure was the major impact of climate pejoration across iv zones. Similarly, livestock health was majorly negatively affected by climate deterioration though the resurgence of diseases due to climate change. Climate indices could explain 23.0 - 50.2 % of the variations in crop yield and an increased cases of livestock diseases occurrence by 1-9.4 units due to the deterioration in climate conditions across climatic zones. Changes in climatic conditions may also induce microbial proliferation and host susceptibility to result in the emergence, redistribution, and changes in the incidence and intensity of pest infestations. The study concluded that crop-livestock integration is underperforming in Burkina Faso and can be improved. Majority farmers (91.6 %) in the Sudan-Sahel zone are practising full crop-livestock integration, unlike the Sahel (62.3%) and Sudan (48.2%) zones. However, only 14.8%, 10.5% and 5.1 % showed the effectiveness of integration in the Sudan-Sahel, Sahel and Sudan zones, respectively. CLI was comparatively more effective in Sudan-Sahel (65.9±32.0 %) than Sahel (44.9±29.5 %) and Sudan zones (35.6±35.0 %). Integration indicators were significantly associated with farm emissions, productivity, biodiversity and soils nutrients. CLI is also a tree-based system with high sequestration potential that could significantly counterbalance the whole system emissions. However, the coverage of fodder needs is negatively associated with soils nutrients content indicating field nutrient mining if an appropriate scheme of nutrient return to the soils as manure is not set. An adequate combination of CLI components offers an opportunity to build resilient farming systems in Burkina Faso to adapt to the changing climate.
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    Design, fabrication, testing and evaluation of two aeroponic systems as alternative production methods for seed yams in Ghana.
    (2017-01-23) Oteng-Darko, Patricia
    Yam is one of the most important dietary sources of energy for households in West-Africa. Yam stores relatively longer than most root crops and this attribute have gained it recognition as a food security crop in Ghana. More effort has been put into its research and production as has been seen by numerous government interventions over the years. However, inadequate access and high cost of seed yams have prevented farmers from intensive sustainable production. New technologies to increase and make available quality seed yams to farmers can boost yam production, increase food security and improve farmers’ livelihoods. In this regard, two aeroponic systems were developed and evaluated. The two systems; power-dependent (pressurised) and power-independent (gravity-fed) were evaluated using a split-split plot design at the CSIR-Crops Research Institute. The evaluations were carried out to assess the technical and agronomic performance of the systems. The aeroponic units were the main plots, the nutrient concentrations the sub-plot, and the yam varieties the sub-sub plot. Data collected on performance of the various treatments were subjected to analysis of variance and judged significant at p<0.05. Technical evaluation of the two aeroponic systems gave Christensen’s Coefficient for water distribution uniformity values were 97.52 % and 94.49 % for the power-dependent and power-independent systems respectively. Agronomic performance showed significant differences in number of mini-tubers harvested and weight of mini-tubers under the different aeroponic systems. Field evaluation of harvested mini-tubers also showed significant differences in final yields under the various nutrient concentrations. Economic analysis of the two systems showed a benefit-cost ratio in favour of the power-independent system. Various recommendations were made after a repeat of the experiment. The power-independent system would be disseminated to smallholder farmers for seed propagation.
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    Development of Alumina Modified Laterite Material for Fluoride Removal from Contaminated Water
    (August, 2016) Osei, Juliet;
    Fluoride in groundwater is a threat to the provision of potable water to our rural communities because continuous consumption of water contaminated with fluoride could lead to dental fluorosis or even in extreme cases, skeletal fluorosis. Many fluoride removal techniques have been suggested but most of them have been found not to be practical and sustainable in Ghana as they are either expensive or need highly skilled personnel to operate. The need for a local adsorbent which is less expensive and effective for fluoride removal is of much relevance. Laterite has been identified as a local adsorbent which is readily available and not expensive. However, there have been debates among researchers about the effectiveness of laterite to remove fluoride. This study investigated the characteristics of three (3) laterites from three locations of the Upper East Region for fluoride removal. These areas are Agamolga, Balungu and Dua. Chemical and mineralogical analyses performed using X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD) methods showed varying amounts of iron oxide/hydroxide (goethite/hematite), silica and kaolinite. Scanning Electron Microscopy (SEM) combined with Energy Dispersive X-ray (EDX) showed that the minerals are intimately associated. Isoelectronic Point (IEP) value was influenced by the mineral composition with the larger IEP value corresponding to higher iron oxide/hydroxide content. The study measured the responses of the different laterites to fluoride uptake under different conditions of pH, temperature, particle size of adsorbent and initial concentration of fluoride solution. The responses showed that Agamolga and Balungu laterites could remove fluoride better than Dua laterite mainly due to the chemical and mineralogical constituents of these two laterites as compared to Dua laterite which has high silica content. To improve the adsorption capacity of the iv laterite for fluoride uptake, an alumina modified laterite (AML) was developed using Balungu laterite. The effect of treatment temperature and application to different conditions of fluoride uptake was investigated including adsorbent dosage, initial fluoride concentrations, solution pH and fluoride uptake in the presence of other competing anions. The response of AML to the different experimental conditions shows that the material is capable of removing fluoride to a level below the WHO recommended limit of 1.5 mg/L. At a dosage of 4% solids, AML could remove fluoride from 10±0.2 to 0.42 mg/L without any pH adjustment within 35 minutes. The results indicated that the adsorption characteristics of AML were not significantly affected in the pH range of 6-9 and this means pH adjustment of the raw water is unnecessary. The results also showed that there was an improvement on the adsorption capacity as the raw laterite assumed an adsorption capacity of 0.55 mg/g whereas the AML material assumed a value of 0.69 mg/g. The results also showed little or no significant change in fluoride adsorption by AML in the presence of other competing ions such as chloride, sulphate, phosphate, bicarbonate and nitrates.
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    Development of Asphalt Pavement Temperature Prediction Models for the Climatic Conditions of Ghana
    (2023-07) Ntramah, Simon
    Asphalt pavement temperature finds application in several areas of pavement engineering including pavement structural evaluation and design, asphalt mixture design, asphalt material aging characterisation, and asphalt binder grade selection. Predictive models may be used in the estimation of asphalt pavement temperature when necessary, however, such models tend to have limited transferability and applicability to other regions where the environmental conditions are significantly different from those under which the models were developed. To avoid the risk of using foreign-developed models in estimating the temperature of asphalt pavements in Ghana using local data, this research set out to develop asphalt pavement temperature prediction models applicable to the climatic conditions of the country. Two locations in the country, one within the Savannah climatic zone and the other within the Forest climatic zone, were used for the study. Mid-depth and surface asphalt pavement temperatures, along with climatic data, were collected over a 12-month period (May 2022 to April 2023) at the two study locations. The dataset was then used to develop separate asphalt pavement temperature prediction models applicable to each climatic zones. Additional pavement temperature and climatic data were also collected on separate roads within the corresponding climatic zones for model validation. When tested against some high-rated foreign-developed models, using local environmental data inputs, the locally-developed models predicted asphalt pavement temperatures that were much superior in accuracy (R2 ≥ 0.919, RMSE < 2.8 ºC) to those predicted using the best-performing foreign-based model (R2 ≤ 0.905, RMSE ≥ 3.2 ºC). The local models are, therefore, recommended for predicting mid-depth asphalt pavement temperatures in the Forest and Savannah zones of Ghana for pavement engineering purposes.
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    Drought-Heatwaves’ Dynamics with Land Use Land Cover Types under the West African Monsoon System
    (KNUST, 2023-08) RAGATOA, DAKÉGA SABERMA
    Heatwaves are prolonged periods of abnormal heat that can adversely impact human and animal well-being, public infrastructure, agriculture, wildfire occurrence and severity, and workplace efficiency. With increasing global warming, heatwaves and droughts are predicted to worsen. However, there are only a few documented cases of heatwaves in Africa, and less research in West Africa has explored the thermodynamics of heatwaves in the region. This study seeks to comprehensively investigate the dynamics of heatwaves, particularly their interaction with landatmosphere processes and droughts as compound events in three climate zones in West Africa. The research compares heatwave and heat-stress occurrences and their coincidental intensity with drought, using satellite, reanalysis, and in-situ datasets from 1981 to 2020. The study uses Cumulative Heat (CumHeat or Heatcum) and Universal Thermal Climate Index (UTCI) to measure heatwaves, Standardized Precipitation (Evapotranspiration) Index (SPI or SPEI) for drought, and Normalized CumHeat for temperature (Tmax and Tmin), UTCI, and Wet-Bulb Globe Temperature (WBGT) to examine heatwave dynamics. The study employs the ECMWF Year of Polar Prediction (YOPP) dataset to determine the main temperature advection and tendency terms that contribute to heatwaves in selected cases (2018, 2019, and 2020) covering different climate zones, from 1000 hPa, 925 hPa, to 850 hPa, and 700 hPa. The study also uses validated coupled RegCM-CLM simulation outputs initialized with soil moisture to compute SPEI and the normalized heatwave indices. The Drought-heatwave (D-HW) events from observational data showed lower frequency and intensity than the gridded dataset. The West African monsoon system is experiencing an increase in the intensity and duration of UTCI and Tmax heatwaves, mainly before or after the monsoon phase, with some occurrences during the monsoon phase. An increasing trend in the intensity and duration of heatwaves, up to 40 days, has been observed in the gridded dataset, and there is a higher likelihood of WBGT occurrence during the night. The study found that the differences in heatwave indices are primarily due to the sensitivity to moisture and wind. The intensity of heatwaves exhibits asymmetric statistical responses to moisture content deficits, particularly in the Guinea zone and some parts of Sudan (Coast of Senegal). In the Eastern part of West Africa, the opposite reaction to mid-latitudes is observed, where there is an increase in moisture before and during a high heatwave. The impact of soil moisture on heatwaves extends to the 6th level (8th level) about 0.492912 m (1.38283 m) into the soil. These findings could help improve weather forecasting, predict the impacts of heatwaves, and design adaptation strategies to reduce the vulnerability of populations to heatwaves. Additionally, the results contribute to developing more accurate and robust climate models that can better simulate the behaviour of heatwaves and their interactions with other climate variables.
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    Effect of Climate Change and Variability on Pearl Millet (Pennisetum glaucum (L.) R. Br.) Production in the Sudanian and Sahelian Agro-Ecological Zones in Mali
    (May, 2016) Touré, Halimatou Aboubacar
    Climate change is expected to increase vulnerability in all agro-ecological zones of Mali through rising temperature and more erratic rainfalls, which will have drastic consequences on food security and economic growth. This study aimed at assessing the effect of Climate Change and Variability on Pearl Millet (Pennisetum glaucum (L.) R. Br.) Production in the Sudanian and Sahelian Agro-Ecological Zones in Mali. First, the perception of farmers on climate change variability and their adaptation practices to overcome or reduce the negative impacts of climate change on their farming system as well as their livelihoods were investigated in the Sahelian zone. Therefore, 119 farmers’ household including women and youth were randomly selected and interviewed using structured questionnaire. Next, the changes in trends of daily temperature and precipitation extremes in Sotuba and Cinzana during the period 1961 - 2014 were assessed. In order to investigate extreme precipitation and temperature, daily minimum and maximum records for two stations (Ségou and Bamako) were collected at the Aghrymet Meteorological Centre of Niamey for the period 1961-2014. Finally, the performance of two millet varieties in two agroecological zones of Mali was assessed using the DSSAT (The decision support system for agrotechnology transfer) model under different climate conditions. Two years’ experiments were therefore conducted at Agricultural Research Station of Sotuba and Cinzana in the randomised complete block design with 4 replications. The fertiliser treatments included Control, MANURE, NPK and NPK+MANURE. DSSAT model were used to simulate crop grain yields under 2 different weather conditions (historical and future). The results showed that farmers perceived a decrease in annual rainfall as the main factors of climate change and variability. Several strategies such as selling of animals, planting improved crop varieties, engaging in new activities (outside agriculture) and credit were the commonly preferred adaptation strategies to deal with climate change and variability. A significant decrease of warming trends in cool days, cool nights, whereas warm extreme nights, day times and warm spells on the contrary showed positive significant increasing warming throughout the Ségou Region. The results of precipitation extremes for Ségou showed significant decrease in consecutive wet and extremely wet day. The study provided evidence that during the last 53 years, Ségou was particularly affected by warm extremes based on night time indices rather than cold extremes based on day time indices. At Sotuba, the average grain yield was 1293 kg ha-1and 1503 kg ha-1 for the years 2013 and 2014, respectively. In Cinzana, the observed average grain yields in 2013 and 2014 were 1390 and 1530 kg ha-1, respectively. The analyses did show significant differences between the varieties and among the fertilizer treatments. Moreover, millet yield responded to the different historical climatic conditions under all treatments. In line with the experimental data, the highest historical grain yields were achieved when the combination NPK+MANURE was applied. Millet grain yields were higher under the simulations with historical weather data than the simulations with climate change scenarios. Simulation of climate change effects on millet grain yield showed that all scenarios underestimated crop yield compared to the Baseline for all treatments and both varieties. Significant differences (P < 0.05) were revealed among the scenario outputs. All the varieties showed lowest grain yields under the four treatments for ACCESS1-0 (Hot-Wet) among the scenarios. Based on the findings of this study, policy could be developed to enhance farmers’ adaptation strategies in the Sudanian and Sahelian zones of Mali.
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    Effects of variety, harvest age and pre-treatment on the drying characteristics and baking quality of cassava flour
    (July, 2016) Ekete, Eje Brendan
    Cassava is an important tropical crop that is widely grown and consumed in different forms across various countries in the tropics. It has great potentials for use in the bakery and other food industries for the production of value added products. The effects of harvest age, chipping, grating, toasting and citric acid pre-treatments on drying characteristics and baking quality of Ampong, Broni and Otuhia cassava varieties were investigated. Pre-treatment had the greatest influence on the drying characteristics as more than 50 % of the drying time was saved by toasting and grating pre-treatments. Henderson and Pabis, Page and Newton models adequately predicted the drying behaviour of the cassava varieties but the best prediction was achieved with the Page’s model. The proximate composition of the cassava flour was significantly (p ≤ 0.05) affected by harvest age, variety and pre-drying treatments. The flours obtained had satisfactory quality attributes in terms of protein, fat, fibre, ash, carbohydrate, moisture content, pH and cyanogenic potentials. The three cassava varieties produced flours with low cyanide contents of 2.48 mg HCNeqv/kg to 6.99 mg HCNeqv/kg dry matter. These values are below the WHO recommendation of cyanide content which is not to be greater than 10 mg HCNeqv/kg dry matter of cassava flour (WHO/FAO, 2013). Hence the flours could be safely consumed by humans without any concern of cyanide toxicity. The water binding capacity, swelling power, water and oil absorption capacities of the cassava flours were significantly (p ≤ 0.05) affected by variety, harvest age and pre-treatment while solubility was affected by only harvest age and pre-treatment. The Otuhia cassava variety had relatively lower gelatinization temperature and peak time values while Otuhia and Ampong varieties had higher peak and final viscosity values. The setback viscosity values of the flour from the three cassava varieties did not differ iv from each other. Grating pre-treatment had the highest peak viscosity value while the setback and final viscosity values of toasted and grated samples were higher than the others. The early gelatinization, high peak viscosity, setback and final viscosities generally exhibited by the flour samples were good indicators of their suitability for use in the bakery industry. Results from the baking experiment indicated that the specific volume and sensory attributes of bread samples containing 20% cassava flour produced from five different pre-treatments of Otuhia variety harvested at 14 months compared very well with the control sample. Composite bread with acceptable sensory qualities were produced from flour containing up to 40% toasted and 30% grated cassava which was not significantly different (p ≤ 0.05) from bread containing 100% wheat flour.