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Item Developing capacity for impactful use of Earth Observation data: Lessons from the AfriCultuReS project(Environmental Development, 2022) Pritchard, R.; Amponsah, M.; Alexandridis, T.; et al.An increasing number of products and services based on satellite Earth Observation (EO) data are being developed for use by decision-makers in African agricultural contexts, providing information such as weather and climate forecasts, crop yields and water availability. Capacity development Supporting the impactful use of EO data is a key component of many EO-for-development initiatives, but there is little consensus over where or how capacity should be developed. Our goal in this piece is to provide a critical perspective on the capacity development required to support the creation of of more impactful EO data services. Drawing on a capacity needs assessment carried out as part of the AfriCultuReS project (a major EO-for-development initiative), we identify proximate factors which inhibit the success of EO data services, such as flawed communication strategies, low relevance in African agricultural contexts, duplication of existing products, and lack of financial sustainability. We link these proxies challenges to deeper issues such as unequal access to funding and resources, fragmentation in the EO field, and relational asymmetries of power, all of which combine to exclude important forms of knowledge from decision-making. Based on this needs assessment, we argue that capacitydevelopment requires broader systems-based approaches which develop the capacities of all actors (including those in the Global North) to respect different forms of knowledge, use and participate in co-design approaches, and recognise and challenge the asymmetries of power which currently limit the involvement of certain groups in processes of EO data service design.Item Framework for WASH Sector Data Improvements in Data-Poor Environments, Applied to Accra, Ghana(Water, 2018) Koppelaar, R.E.M.; Sule, M.N.; Mensah, F.K.; et al.Improvements in water, sanitation and hygiene (WASH) service provision are hampered by limited open data availability. This paper presents a data integration framework, collects the data and develops a material flow model, which aids data-based policy and infrastructure development for the WASH sector. This model provides a robust quantitative mapping of the complete anthropogenic WASH flow-cycle: from raw water intake to water use, wastewater and excreta generation, discharge and treatment. This approach integrates various available sources using a process-chain bottom-up engineering approach to improve the quality of WASH planning. The data integration framework and the modelling methodology are applied to the Greater Accra Metropolitan Area (GAMA), Ghana. The highest level of understanding of the GAMA WASH sector is achieved, promoting scenario testing for future WASH developments. The results show 96% of the population had access to improved safe water in 2010 if sachet and bottled water was included, but only 67% if excluded. Additionally, 66% of 338,000 m3 per day of generated wastewater is unsafely disposed locally, with 23% entering open drains, and 11% sewage pipes, indicating poor sanitation coverage. Total treated wastewater is <0.5% in 2014, with only 18% of 43,000 m3 per day treatment capacity operational. The combined data sets are made available to support research and sustainable development activities.Item Institutional arrangement for mitigating and adapting to climate change-related flood risk in Greater Accra Metropolitan Area (GAMA)(City and Environment Interactions, 2024) Owusu, A.B.; Adu-Boahen, K.; Dadson, I.Y.Episodic floods, attributable primarily to climate change, global warming, and sea level rise, have worsened and continue to be a significant threat to life. Building resilience and improving the adaptive capacities of com munities under threat will require institutional and cross-agency collaboration. This paper assessed institutional arrangements for mitigating and adapting to climate change-related flood risk in GAMA, Ghana. Using a descriptive cross-sectional survey, the study collected and analysed data from 65 private businesses and governmental, community, and civil society organisations to assess how institutions collaborate in preparing and adapting to flood risks in the study area. The study finds that frequent flooding, destruction of property and lives, and regular community agitations have triggered high-level consciousness, institutional arrangements, and collaboration within and among communities to build capacity and resilience. In addition, organisations have been educating indigenes on flood preparedness, providing relief items to support flood victims, and conducting training and research. Organisations have also supported communities in developing sandbags, planning sea defence mechanisms, providing rescue and evacuation assistance, providing transportation and logistics, and relocating stranded flood victims. Despite these efforts, the lack of adequate funding and logistics, coupled with the absence of proper consultation and involvement of most organisations in making national-level decisions on climate change and flood-related issues, have rendered flood management efforts less effective. This paper makes the case that proactive and collaborative flood responses should replace reactive and individual approaches to improve flood control efficacy and minimise casualties and property losses.Item Patterns and drivers of disturbance in tropical forest reserves of southern Ghana(IOP Publishing, 2023-05-22) Mensah, F.; Wanyama, D.; Wimberly, M.C.Ghana has retained a substantial area of tropical forests in an extensive network of protected reserves. These forests are impacted by land uses such as logging, mining, and agriculture as well as wildfires. We studied forest disturbance and recovery from 2013 to 2020 using annual maps of forest cover derived from Landsat imagery. Fire-associated disturbance was distinguished using VIIRS active fire data. We used boosted regression trees to model disturbances in closed and open forests as a function of climate variability, human accessibility, and landscape structure. A total of 3562 km2 of forest reserves were disturbed, of which 17% (615 km2 ) were fire disturbances and 83% (2946 km2 ) were non-fire disturbances. Of the total disturbed area, 68% was degradation (change from closed to open forest), 28% was open forest loss, and only 4% was closed forest loss. Over the same period, 2702 km2 of forest reserves recovered, with 1948 km2 of these recovering to closed-canopy forests. Fire disturbances were strongly associated with precipitation anomalies and occurred mostly in drier years, whereas non-fire disturbances had weaker relationships with precipitation. Disturbances in closed forests occurred in landscapes where closed forest cover was already low. In contrast, disturbances in open forests were most common in locations with intermediate levels of population pressure from nearby cities and proximity to non-forest land cover. The results support the idea that forest disturbance in Ghana is a multi-stage process involving degradation of closed forests followed by loss of the resulting open forests. Although non-fire disturbance rates are consistent from year to year, sharp increases in fire disturbance occur in drought years. Locations with the highest disturbance risk are associated with measurable indicators of climate, human pressure, and fragmentation, which can be used to identify these areas for conservation and forest restoration activities.Item Differentiating oil palm plantations from natural forest to improve land cover mapping in Ghana(Remote Sensing Applications: Society and Environment, 2023) Abramowitz, J.; Cherrington, E.; Griffin, R.; Muench, R.; Mensah, F.Tree crops like oil palm present a unique challenge in land cover mapping, as they are often misclassified as natural forest. The area cultivated with oil palm in Ghana has rapidly expanded since 2000, and production is expected to continue to increase. Sentinel-1 and Sentinel-2 satellite data was used as inputs to a random forest classifier in Google Earth Engine to map mature, closed-canopy oil palm extent in 2019 of a Ghana study area that includes both industrial plantations and smallholders. The combination of Sentinel-1 and Sentinel-2 bands and derived indices outperformed either satellite alone for mapping industrial oil palm (90.3% overall ac curacy). A separate accuracy assessment for this combined input approach demonstrated high accuracy mapping smallholders as well (80.4% overall accuracy), a key challenge in the West African context. To validate these findings, results were compared with available production information and a global oil palm remote sensing product. The resulting map can inform sustainable oil palm efforts in Ghana, which is understudied in current oil palm remote sensing literature, and the methodology provides an example for future studies of oil palm sourcing areas using only publicly available data.Item Differentiating oil palm plantations from natural forest to improve land cover mapping in Ghana(Remote Sensing Applications: Society and Environment, 2023) Abramowitz, J.; Cherrington, E.; Mensah, F.; et al.Tree crops like oil palm present a unique challenge in land cover mapping, as they are often misclassified as natural forest. The area cultivated with oil palm in Ghana has rapidly expanded since 2000, and production is expected to continue to increase. Sentinel-1 and Sentinel-2 satellite data was used as inputs to a random forest classifier in Google Earth Engine to map mature, closed-canopy oil palm extent in 2019 of a Ghana study area that includes both industrial plantations and smallholders. The combination of Sentinel-1 and Sentinel-2 bands and derived indices outperformed either satellite alone for mapping industrial oil palm (90.3% overall accuracy). A separate accuracy assessment for this combined input approach demonstrated high accuracy mapping smallholders as well (80.4% overall accuracy), a key challenge in the West African context. To validate these findings, results were compared with available production information and a global oil palm remote sensing product. The resulting map can inform sustainable oil palm efforts in Ghana, which is understudied in current oil palm remote sensing literature, and the methodology provides an example for future studies of oil palm sourcing areas using only publicly available data.Item Historical trends of degradation, loss, and recovery in the tropical forest reserves of Ghana(Taylor & Francis Group, 2022) Wimberly, M.C.; Dwomoh, F.K.; Numata, I.; Mensah, F.; Amoako, J.; Nekorchuk, D.M.; McMahon, A.The Upper Guinean Forest region of West Africa, a globally significant biodiversity hotspot, is among the driest and most human-impacted tropical ecosystems. We used Landsat to study forest degradation, loss, and recovery in the forest reserves of Ghana from 2003 to 2019. Annual canopy cover maps were generated using random forests and results were temporally segmented using the LandTrendr algorithm. Canopy cover was predicted with a predicted-observed r2 of 0.76, mean absolute error of 12.8%, and mean error of 1.3%. Forest degradation, loss, and recovery were identified as transitions between closed (>60% cover), open (15–60% cover) and low tree cover (< 15% cover) classes. Change was relatively slow from 2003 to 2015, but there was more disturbance than recovery resulting in a gradual decline in closed canopy forests. In 2016, widespread fires associated with El Niño drought caused forest loss and degradation across more than 12% of the moist semi-deciduous and upland evergreen forest types. The workflow was implemented in Google Earth Engine, allowing stakeholders to visualize the results and download summaries. Information about historical disturbances will help to prioritize locations for future studies and target forest protection and restoration activities aimed at increasing resilience.Item Urban sprawl and land use/land-cover transition probabilities in peri-urban Kumasi, Ghana(West African Journal of Applied Ecology, 2018-10) Abass, K.; Adanu, S.K.; Gyasi, R.M.This paper examines Land Use and Land Cover (LULC) transition probabilities and its implications for KumasiMetropolis using remote sensing image analysis technique. Methods used for the study include sub-setting ofsatellite images for the metropolis using the metropolitan shapefile boundary and classification of the images using maximum likelihood image classification algorithm. A Markov Model was applied to predict probabilities of LULC changes in 15 years (2016 - 2031). Study results show the probability of urban lands changing to agricultural land as low and so is the probability of farmland transitioning to urban land use. Vegetation however shows a high probability of change to built-up area while the likelihood of change from water to other cover types is not a possibility. The study recommends enforcement of relevant land use policies backed by vigorous public education to make sustainable urban land use in the Metropolis a reality. Also, vertical rather than horizontal construction of buildings could stem the sprawling city.Item Peri-urbanisation and loss of arable land in Kumasi Metropolis in three decades: Evidence from remote sensing image analysis(Land Use Policy, 2018-03) Abass, K.; Adanu, S.K.; Agyemang, S.This paper examined the effects of peri-urbanisation on arable land in Kumasi Metropolis. The study involved classification of Landsat Thematic Mapper (TM) 1986 imagery and images from Enhanced Thematic Mapper Plus (ETM+) 2004 and Landsat 8 Operational Land Image and Thermal Infrared Sensor (OLI/TIRS) image for 2016 to show land use and cover changes in the Metropolis. The results show that the Metropolis has undergone significant land use and land cover changes in thirty years with negative repercussions for food crop production. While urban land use increased by 54.6% between 1986 and 2016, arable land declined by 15.6% over the same period. The results show a strong positive correlation between the size of arable land and crop output over a fifteen-year period. The paper calls for legislative enforcement as well as standards on urban land use and development as enshrined in the 2016 Land Use and Spatial Planning Act to ensure that land use in the city is consistent with sustainable principles.Item Modelling the effect of environmental disturbance on community structure and diversity of wetland vegetation in Northern Region of Ghana(Aquatic Ecology, 2019-03) Nsor, C.A.; Antobre, O.O.; Mohammed, A.S.; Mensah, F.The substantial variations in the anatomy, physiology and life-history trait of wetland plants tend to limit their ability to tolerate environmental stressors and can consequently affect their community composition and distribution. Comparative studies of wetland plants among water bodies of varying limnological characteristics are useful in understanding the different wetland plant communities’ responses to different environmental drivers. This study examined how community structural assemblages in six different tropical wetlands responded to environmental disturbances over a 1-year period (January–December 2017). They included three standing marshes (Kukobila, Tugu and Wuntori marshlands); two riparian systems (Adayili and Nabogo); and one artificial wetland (Bunglung). The prevalence index method was used to categorize plants as wetland or non-wetland species. Geometric series, individual-based rarefaction and Renyi diversity ordering models were applied to quantify community structural assemblages, while a direct ordination technique (CCA) was used to determine the how they respond to the influence of environmental factors. A total of 3034 individuals, belonging to 46 species from 18 families, were registered across the six wetlands. Grasses, herbs and woody species constituted 42.2%, 42.2% and 15.5%, respectively. Obligate species constituted 30.4%, while facultative wetland and obligate upland species were 47.8% and 26.1%, respectively. Wuntori marshland (n = 768) recorded the highest species per plot (18.73 ± 2.49), while Adayili riparian wetland (n = 260) was the least recorded (6.34 ± 1.80). Chrysopogon zizanioides, Echinochloa stagnina and Pennisetum polystachion were the most abundant species. Species assemblages were influenced by grazing, farming, fire, phosphorus, potassium and soil pH. These variables explained 61.29% of total variances in species abundance distribution, richness and diversity. The results highlight the threats on the wetlands and the need to protect them from further degradation.Item Impacts of coastal inundation due to climate change in a CLUSTER of urban coastal communities in Ghana, West Africa(Remote Sensing, 2011-12) Addo, K.A.; Larbi, L.; Amisigo, B.; Ofori-Danson, P.K.The increasing rates of sea level rise caused by global warming within the 21st century are expected to exacerbate inundation and episodic flooding tide in low-lying coastal environments. This development threatens both human development and natural habitats within such coastal communities. The impact of sea level rise will be more pronounced in developing countries where there is limited adaptation capacity. This paper presents a comprehensive assessment of the expected impacts of sea level rise in three communities in the Dansoman coastal area of Accra, Ghana. Future sea level rises were projected based on global scenarios and the Commonwealth Scientific and Industrial Research Organization General Circulation Models-CSIRO_MK2_GS GCM. These were used in the SimCLIM model based on the modified Bruun rule and the simulated results overlaid on near vertical aerial photographs taken in 2005. It emerged that the Dansoman coastline could recede by about 202 m by the year 2100 with baseline from 1970 to 1990. The potential impacts on the socioeconomic and natural systems of the Dansoman coastal area were characterized at the Panbros, Grefi and Gbegbeyise communities. The study revealed that about 84% of the local dwellers is aware of the rising sea level in the coastal area but have poor measures of adapting to the effects of flood disasters. Analysis of the likely impacts of coastal inundation revealed that about 650,000 people, 926 buildings and a total area of about 0.80 km2 of land are vulnerable to permanent inundation by the year 2100. The study has shown that there will be significant losses to both life and property by the year 2100 in the Dansoman coastal community in the event of sea level rise. © 2011 by the authors.Item Building disaster anticipation information into the Ghana development and poverty mapping and monitoring system(Geo-information for Disaster Management, 2005) Amamoo-Otchere, E.; Akuetteh, B.The Centre for Remote Sensing and Geographic Information Services (CERSGIS), a self-supporting, no-profit organization within the University of Ghana is an implementing agency an European Union supported project for Establishing Mapping and Monitoring System for Development Activities in Ghana (EMMSDAG). The current EDF-funding cycle of three years covers the Rural Phase of the EMMSDAG. The goal of the Rural Phase of the EMMSDAG is an on-line multi-functional/multi-application ArcGIS-driven government-owned data sets on social infrastructure facilities for rural community development projects and impact monitoring and evaluation. Five frontline government institutions are the primary stakeholders of the EMMSDAG - Ministries of Finance and Economic Planning, Local Government and Rural Development, Project Monitoring and Evaluation Unit of the Office of the President, National Development Planning Commission and House of Parliament. These are to be connected on-line through wide area network for direct use of the data resources of the EMMSDAG Laboratory at the CERSGIS. The project should facilitate widespread use (by government and nongovernmental organizations, donors, investors and the private sector in general) of the GIS-driven socio-economic databases to be sustainably maintained by CERSGIS. It will be the primary task of CERSGIS to assist potential and real users in defining profitable/practical uses of the data for problem-searching/defining and problem-solving. The National Disaster Management Organization (NADMO) will be one of the expected users of the EMMSDAG's data resources. © 2005 Springer-Verlag Berlin Heidelberg.Item Total coliforms, arsenic and cadmium exposure through drinking water in the Western Region of Ghana: application of multivariate statistical technique to groundwater quality(Environmental Monitoring and Assessment, 2015-02) Affum, A.O.; Osae, S.D.; Nyarko, B.J.B.; Afful, S.; Fianko, J.R.; Akiti, T.T.; Adomako, D.; Acquaah, S.O.; Dorleku, M.; Antoh, E.; Barnes, F.; Affum, E.A.In recent times, surface water resource in the Western Region of Ghana has been found to be inadequate in supply and polluted by various anthropogenic activities. As a result of these problems, the demand for groundwater by the human populations in the peri-urban communities for domestic, municipal and irrigation purposes has increased without prior knowledge of its water quality. Water samples were collected from 14 public hand-dug wells during the rainy season in 2013 and investigated for total coliforms, Escherichia coli, mercury (Hg), arsenic (As), cadmium (Cd) and physicochemical parameters. Multivariate statistical analysis of the dataset and a linear stoichiometric plot of major ions were applied to group the water samples and to identify the main factors and sources of contamination. Hierarchal cluster analysis revealed four clusters from the hydrochemical variables (R-mode) and three clusters in the case of water samples (Q-mode) after z score standardization. Principal component analysis after a varimax rotation of the dataset indicated that the four factors extracted explained 93.3 % of the total variance, which highlighted salinity, toxic elements and hardness pollution as the dominant factors affecting groundwater quality. Cation exchange, mineral dissolution and silicate weathering influenced groundwater quality. The ranking order of major ions was Na+ > Ca2+ > K+ > Mg2+ and Cl− > SO4 2− > HCO3 −. Based on piper plot and the hydrogeology of the study area, sodium chloride (86 %), sodium hydrogen carbonate and sodium carbonate (14 %) water types were identified. Although E. coli were absent in the water samples, 36 % of the wells contained total coliforms (Enterobacter species) which exceeded the WHO guidelines limit of zero colony-forming unit (CFU)/100 mL of drinking water. With the exception of Hg, the concentration of As and Cd in 79 and 43 % of the water samples exceeded the WHO guideline limits of 10 and 3 μg/L for drinking water, respectively. Reported values in some areas in Nigeria, Malaysia and USA indicated that the maximum concentration of Cd was low and As was high in this study. Health risk assessment of Cd, As and Hg based on average daily dose, hazard quotient and cancer risk was determined. In conclusion, multiple natural processes and anthropogenic activities from non-point sources contributed significantly to groundwater salinization, hardness, toxic element and microbiological contamination of the study area. The outcome of this study can be used as a baseline data to prioritize areas for future sustainable development of public wells. © 2015, Springer International Publishing Switzerland.Item Spatiotemporal analysis of climate variability impacts on malaria prevalence in Ghana(Applied Geography, 2015-06) Adu-Prah, S.; Kofi Tetteh, E.There are conflicting results from research on the impacts of temperature and rainfall on malaria prevalence. As a result predicting malaria prevalence still remains a challenge. Generating relevant information on the role of temperature, rainfall, and humidity on malaria prevalence at different geographic scales is critical to efforts to combat the burden of prevalence. For better understanding of climate variability and the impacts on malaria prevalence, this study examined the varying spatial and seasonal distribution in malaria prevalence over time in Ghana. We used trajectory and time series analyses for temporal distribution and conducted GIS-based analyses of the spatial distribution of yearly malaria incidence and climate variables. We observed that the national annual malaria incidence has increased. Considerable inter-annual variations were also detected in the intensity of incidence across regions characterized with varying rainfall and temperature regimes. The results indicated that temperature and humidity have some association with malaria prevalence in Ghana. Although annual rainfall in the model was found to be less significant, there is evidence of rainfall as a predictor of malaria in Ghana. These findings show that public health resource allocations should focus on the areas with the highest malaria risk in Ghana. Spatiotemporal analysis of climate variability impacts on malaria prevalence in Ghana | Request PDF. Available from: https://www.researchgate.net/publication/276853053_Spatiotemporal_analysis_of_climate_variability_impacts_on_malaria_prevalence_in_Ghana [accessed Sep 18 2018].Item Remote Sensing and GIS Based Assessment of Land Degradation and Implications for Ghana’s Ecological Zones(Environmental Practice, 2015-03) Mensah, F.; Adanu, D.K.; Adanu, S.K.Land degradation and desertification have become complex environmental, social, and economic concerns in Ghana owing to decline in agricultural productivity, loss of biodiversity, and forced out-migration from degraded lands to cities in search of jobs or to rural forested communities for farming, resulting in further deforestation. In an attempt to address these complex land degradation and desertification problems, particularly in the northern areas of Ghana, land degradation was assessed in six major ecological zones of Sudan savanna, Guinea savanna, forest transition, moist semi-deciduous forest, evergreen forest, and coastal savanna. The objectives of the assessment were to: (a) analyze current satellite images to document land degradation, (b) model trends of land degradation, and (c) create a desertification hazard map for Ghana. Land degradation was modeled by using ArcGIS 9.3; satellite image analysis was conducted by using ERDAS Imagine software. Land degradation indicator data layers were soil, vegetation, climate, and land management data. The Modified Mediterranean Desertification and Land Use Model was adapted to model desertification and land degradation, which resulted in the production of a land degradation risk map for Ghana. In addition to the modeling, satellite image based land cover classification results from 2000 to 2008 showed evidence of approximately 880.006 sq km of land degradation in Ghana.Environmental Practice 00: 1-13 (2015) (PDF) RESEARCH ARTICLE: Remote Sensing and GIS Based Assessment of Land Degradation and Implications for Ghana’s Ecological Zones. Available from: https://www.researchgate.net/publication/273528995_RESEARCH_ARTICLE_Remote_Sensing_and_GIS_Based_Assessment_of_Land_Degradation_and_Implications_for_Ghana%27s_Ecological_Zones [accessed Sep 07 2018].