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Impact of Tailings on Surrounding Streams at a Mining Area in Sierra Leone
Ishmail Sheriff,
Eldred Tunde Taylor,
Alusine Bai Kamara,
Abdul Sannoh
Issue:
Volume 7, Issue 5, October 2018
Pages:
202-208
Received:
18 July 2018
Accepted:
8 August 2018
Published:
6 September 2018
Abstract: Access to clean water and sanitation is the centerpiece of Africa water vision 2025 and Goal six (6) of the 2030 UN agenda for Sustainable Development. Considering the current national WASH regulatory structures in Sierra Leone, meeting these targets enshrined in the policy documents would be a critical challenge for the government. The overarching objectives sought by the study were to determine the available composition of physio-chemical parameters and evaluate impact of mine tailings on nearby water bodies within the operational areas of Sierra Rutile Mining Company Limited. Twenty-four (24) water samples obtained from six (6) streams were tested for seventeen (17) physical and chemical parameters. About 30% of the indicators were noted to be above the permissible limit of water quality standard in almost all of the sampling sites. A pattern of decrease concentration downstream for Zn, Pb and Cu was observed but those at the tailing points were noted otherwise. The results revealed that mining activities have to an extent negative impact on the local water sources. Consequently, certain indicators were considered to be of public health concern considering their baseline levels. It would be necessary for the company to examine the mechanism of discharge of tailings and strengthen the environmental surveillance within its concessionary areas to enhance sustainability with the ultimate goal to improve environmental performance.
Abstract: Access to clean water and sanitation is the centerpiece of Africa water vision 2025 and Goal six (6) of the 2030 UN agenda for Sustainable Development. Considering the current national WASH regulatory structures in Sierra Leone, meeting these targets enshrined in the policy documents would be a critical challenge for the government. The overarching...
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The Traditional Knowledge Associated to Biodiversity in an Age of Climate Change
Lun Yin,
Misiani Zachary,
Yanyan Zheng
Issue:
Volume 7, Issue 5, October 2018
Pages:
209-215
Received:
1 August 2018
Accepted:
21 August 2018
Published:
15 September 2018
Abstract: Climate change has largely influenced the biodiversity in the world, as the biodiversity hotspots areas are often also rich in cultural diversity, the local peoples have rich traditional knowledge associated to biodiversity, and these knowledge also provide alternative information about climate variability and climate change based on the experience and practices of biodiversity resource use. This review work examines the researches about traditional knowledge associated to biodiversity in monitoring and adapting to changing climatic conditions in different parts of the globe. We reviewed different reports from both International and Regional Organizations whereby we based our findings from the traditional knowledge and climate change, the traditional knowledge’s perception and lastly traditional knowledge’s adaption to climate change. In our findings we realized that traditional knowledge associated to biodiversity is not only effective toolbox, but also a process to adopt to the climate change at local level. Lastly this review also demonstrates how local people use their traditional knowledge about the climate to guide their biodiversity resource and its management. The disasters arising from negative impacts of climate change has brought many risks and threats to the indigenous peoples. This paper highlights the importance of integrating the scientific models in conjunction with traditional knowledge system of indigenous peoples. Integrating this traditional knowledge can add a significance value to the development of sustainable climate change mitigation and adaptation strategies that are rich in local content. It was observed that the traditional knowledge and coping strategies can no longer be fully adapted to the intensity and frequency of the present climate change due to unlimited resources and also lack the enough support from both local and international communities’ responsible for the climate policies.
Abstract: Climate change has largely influenced the biodiversity in the world, as the biodiversity hotspots areas are often also rich in cultural diversity, the local peoples have rich traditional knowledge associated to biodiversity, and these knowledge also provide alternative information about climate variability and climate change based on the experience...
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Coupled Flow Simulation and Geomechanical Modeling on CO2 Storage in a Saline Aquifer
Issue:
Volume 7, Issue 5, October 2018
Pages:
216-226
Received:
23 July 2018
Accepted:
3 September 2018
Published:
28 September 2018
Abstract: As an option to mitigate the increasing level of greenhouse gas emission, a number of Carbon Capture and Storage (CCS) testing and pilot projects have been brought up all over the world. In general, there are three types of CO2 storage formations, such as deep saline aquifers, depleted oil and gas reservoirs, and un-mineable coal seams. This study is focused on the deep saline aquifer which has the largest potential for CO2 storage. There are a lot of uncertainties associated with this type of storage, such as storage capacity, geomechanical properties, and sealing behaviour of the caprock. Pressure (and temperature) changes during CO2 injection and storage can have significant impact on the stress and strain field and may cause relevant geomechanical problems. This paper shows a case study of a synthetic saline aquifer storage site, where a 15-year injection at a rate of 15 MT/year was simulated. Sealing performance and leakage risk were evaluated. A number of sensitivity studies were conducted to analyse the impacts of different rock properties on CO2 leakage potentials. Coupled flow simulation and geomechanical modeling was performed to monitor stress-strain evolutions and to predict failure potentials in response to pressure changes during CO2 injection and storage. The findings show that CO2 leakage is most sensitive to caprock permeability. Other factors such as reservoir properties, boundary conditions, and perforation intervals also have certain degree of influence on the leakage. During the 15-year injection, there is no significant risk of potential failure; however, this may happen in local area due to formation heterogeneity.
Abstract: As an option to mitigate the increasing level of greenhouse gas emission, a number of Carbon Capture and Storage (CCS) testing and pilot projects have been brought up all over the world. In general, there are three types of CO2 storage formations, such as deep saline aquifers, depleted oil and gas reservoirs, and un-mineable coal seams. This study ...
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Assessing Accuracy of Vegetation Index Method to Estimate Actual Evapotranspiration
Arturo Reyes-González,
Jeppe Kjaersgaard,
Todd Trooien,
Christopher Hay,
Laurent Ahiablame
Issue:
Volume 7, Issue 5, October 2018
Pages:
227-235
Received:
15 August 2018
Accepted:
11 September 2018
Published:
11 October 2018
Abstract: The estimation of actual crop evapotranspiration (ETa) maps using complex equations and remotely sensed shortwave and thermal infrared imagery can be challenging and may require input data that are not available. There is an opportunity, therefore to create a simpler and faster method to generate ETa maps using fewer input parameters for situations where limited input data is available or greater uncertainty in the resulting ET estimates are acceptable. We compared the estimates of ETa produced by a crop coefficient and NDVI-based (Kc-NDVI) method to a full energy balance (EB) method. Clear sky images from Landsat 7 and Landsat 8 were processed and used for the ETa estimations from maize during two growing seasons in eastern South Dakota, USA. The results showed that the ETa values from the Kc-NDVI method were lower than the ETa values from the EB method by 18% for 2015 and 11% for 2016 growing season. During study period the accuracy of ETa estimation decreased 17% with the Kc-NDVI method. For both years the mean bias error was 0.81 mm day-1 and the root mean square error (RMSE) was 0.37 mm day-1. The average daily ETa of 5.3 mm day-1. The Kc-NDVI method performed acceptable for ETa estimations, indicating that this method can be used to estimate ETa with minimum input parameters at focused regional and field scales for short time periods.
Abstract: The estimation of actual crop evapotranspiration (ETa) maps using complex equations and remotely sensed shortwave and thermal infrared imagery can be challenging and may require input data that are not available. There is an opportunity, therefore to create a simpler and faster method to generate ETa maps using fewer input parameters for situations...
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Petro-Structural Characterization of Bonguen Area, Nyong Series, Cameroon: Insight into the Northern Extension of Kribi-Campo Shear Zone
Kouankap Nono Gus Djibril,
Njiosseu Tanko Evine Laure,
Takodjou Wambo Jonas Didero,
Kamguia Woguia Brice,
Afahnwie Ngambu Aloysius,
Fomena Tchinda Hermann,
Folah Mewa Cathy Laurianne
Issue:
Volume 7, Issue 5, October 2018
Pages:
236-241
Received:
22 September 2018
Accepted:
10 October 2018
Published:
24 October 2018
Abstract: The west Bonguen area is located within latitudes 03°25’N to N03°39’N and longitudes 10°04’E to 10°09’ E in South Cameroon. It belongs to the Nyong Series which is the north-western extension of the Congo Craton in Cameroon. In order to highlight the extension of the Kribi-Campo shear zone, petrographic studies and structural analysis were carried out. Mylonitic metagranodiorite outcropping as a large dome in biotite gneiss basement rocks, it is the main rock type in the study area, it is made up of Kfs + Qtz + Bt + Pl + Op. Majority of the minerals shows deformation marks such as sigmoidal shape of Kfs, rolling extension of Qtz ribbons, Subgrains of Qtz and kink-band of Bt. Three (03) deformation phases (D1, D2, and D3) were denoted in Bonguen west. The D1 deformation developed S1 foliation in biotite gneiss basement rocks and is characterized by the alternation of parallel compositional bands and lithological units. The D2 deformation developed S2 mylonitic shistosity, Shear bands (C2-planes) develop oblique to the main S2 mylonitic schistosity (S2-plane) showing dextral ductile shear, V2 veins and B2 boudins. The D3 phase is exclusively highlighted by brittle features such as V3 veins, F3 joints and faults. The area consequently underwent a polyphases ductilo-fragile tectonism dominated by a dextral thrusting kinematics. Bonguen area is here considered as a segment of the northern extension of the Kribi-Campo fault.
Abstract: The west Bonguen area is located within latitudes 03°25’N to N03°39’N and longitudes 10°04’E to 10°09’ E in South Cameroon. It belongs to the Nyong Series which is the north-western extension of the Congo Craton in Cameroon. In order to highlight the extension of the Kribi-Campo shear zone, petrographic studies and structural analysis were carried ...
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