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A Study on the Surface Wettability of Clastic Rocks with Potential Application for CO2 Storage Sites
Umar Bappah Adamu Gholami Raoof Raza Arshad Downey William Samuel Sarmadivaleh Mohammad Shah Afroz A. Nayak Prasanta 《Natural Resources Research》2020,29(3):2051-2061
Natural Resources Research - There have been many studies carried out in the past decades attempting to develop strategies for a safe injection of CO2 into storage sites without leakage and... 相似文献
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This study focused on the influence of base metal mining on heavy metal levels in soils and plants in the vicinity of Arufu lead-zinc mine, Nigeria. Soil samples (0-15 cm depth) and plant samples were collected from cul-tivated farmlands in and around the mine, the unmineralized site and a nearby forest (the control site). The samples were analyzed for heavy metals (Fe, Zn, Mn, Cu, Pb, Cr and Cd) by Atomic Absorption Spectrophotometry (AAS). The physical properties of soils (pH and LOI) were also measured. Results showed that soils from cultivated farm-lands have neutral pH values (6.5-7.5), and low organic matter contents (10%). Levels of Zn, Pb and Cd in culti-vated soils were higher than the concentrations obtained from the control site. These heavy metals are most probably sourced from mining and agricultural activities in the study area. Heavy metal concentrations measured in plant parts decreased in the order of rice leavescassava tuberspeelings. In the same plant species, metal levels decreased in the order of ZnFeMnCuPbCrCd. Most heavy metals were found in plant parts at average concentrations normally observed in plants grown in uncontaminated soil, however, elevated concentrations of Pb and Cd were found in a few cassava samples close to the mine dump. A stepwise linear regression analysis identified soil metal contents, pH and LOI as some of the factors influencing soil-plant metal uptake. 相似文献
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Christopher Iorfa Adamu Therese Nganje Aniekan Edet 《Environmental Earth Sciences》2014,71(9):3793-3811
Hydrochemical studies were carried out in parts of Oban Massif and Mamfe Embayment, Southeastern Nigeria to examine the contributions of barite mining activities on water quality. Pond and stream water samples were collected from six abandoned barite mines and adjoining streams areas during dry and wet seasons. These samples were analysed for physicochemical parameters using standard techniques. The results showed that the quality of water samples in the vicinity of barite mine sites was characterized by low pH, low mineralization, high suspended solids and deep colour. Sodium (Na+) and calcium (Ca2+) are the dominant cations and bicarbonate (HCO3 ?) and sulphate (SO4 2?) the dominant anions. The low concentration of dissolved silica, relatively high concentrations of Na+, HCO3 ? and SO4 2? suggest a combined influence of silicate, carbonate and weathering of mine spoils. The total dissolved solids, total suspended solids, electrical conductivity and major ions (except Na+ and K+) are higher for water draining barite mines from Cretaceous sediments, while Na+, K+, Ba2+ are higher in basement rock areas. Correlation and factor analyses suggest that the main components of the water samples are related to anthropogenic, geogenic, mineralization and environmental controls, while Gibbs diagram plots indicate weathering as the main process controlling the chemistry of water. Computed values of hardness and some irrigational parameters showed that the pond and stream water samples are generally soft and can be used for irrigation. Generally, the water quality satisfied the WHO (2008) and NIS (2007) standards for domestic, agriculture and industrial. However, there is the need to assess the impact of the pollution on the ecosystem and human health while remediation measures are being considered. 相似文献
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Global exponential water demand has resulted in the quantity and quality of household water declining rapidly in recent years. Across Sub-Saharan Africa, many small to medium size towns growing at more than 5% per annum provide the region’s momentum for urbanisation. Owing to the dismal performances of water utilities companies, urban populations have tended to resort to diverse and unsafe sources of household water. Illustrating with the city of Buea in the coastal south west Cameroon, this paper examines the changing trends in water sources and the potential health risks to its populations. It relied on a blend of information ranging from reviews of relevant secondary sources, empirical data to field surveys and laboratory analysis. Key findings point to a high level of water misallocation and non-revenue water by the water utility company; a growing movement of households from the certified pipe-borne water source to unimproved sources as follows: 36% to springs, 20% to wells, 25% to water vendors, 27% to rainwater, and 22% to boreholes and only 11% from open streams to piped water. This has resulted in the presence of coliform bacteria in all alternative water sources in Buea, corroborated by hospital returns on water borne intestinal bacterial infections. Given the proven efficiency of water distribution via public pumps and smaller retailers, there is the urgent need for a change of the water distribution paradigm in small and medium size cities in Sub-Saharan Africa to increase access for more people than through the more costly home connections preferred by utility companies. 相似文献
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Therese N. Nganje Christopher I. Adamu Anthony N. Ugbaja Essang Ebieme Gregory U. Sikakwe 《Arabian Journal of Geosciences》2011,4(1-2):199-205
Water, sediment, and mine spoil samples were collected within the vicinity of the Okpara coal mine in Enugu, Southeastern Nigeria, and analyzed for trace elements using ICP-MS to assess the level of environmental contamination by these elements. The results obtained show that the mine spoils and sediments are relatively enriched in Fe, with mean values of 1,307.8(mg/kg) for mine spoils and 94.15% for sediments. As, Cd, Cr, Mn,Ni, Pb, and Zn in the sediments were found to be enriched relative to the mean values obtained from the study area, showing contamination by these elements. The mean values of Fe, Mn, Cu, and Cr in the mine spoils and mean values of Fe, Cu, Pb, Zn, Ni, Cr, and Mn in sediments, respectively, are above the background values obtained from coal and shale in the study area, indicating enrichment with these elements. The water and sediments are moderately acidic, with mean pH values of 4.22?±?1.06 and 4.66?±?1.35, respectively. With the exception of Fe, Mn, and Ni, all other elements are within the Nigerian water quality standard and WHO limits for drinking water and other domestic purposes. The strong to moderate positive correlation between Fe and Cu (r?=?0.72), Fe and Zn (r?=?0.88), and Fe and As (r?=?0.60) at p?<?0.05 as obtained for the sediments depict the scavenging effect of Fe on these mobile elements. As also shows a strong positive correlation with Mn (r?=?≥ 0.70, p?<?0.05), indicating that Mn plays a major role in scavenging elements that are not co-precipitated with Fe. In water, the strong positive correlation observed between Cr and Cd (r?=?1.00), Cu and Ni (r?=?0.94), Pb and Cu (r?=?0.87) and Zn and Cu (r?=?0.99); Ni and Pb (r?=?0.83) and Zn and Ni (r?=?0.97); and between Pb and Zn (0.84) at p?<?0.05 may indicate similar element–water reaction control on the system due to similarities in chemical properties as well as a common source. Elevated levels of heavy metals in sediments relative to surface water probably imply that sorption and co-precipitation on Al and Fe oxides are more effective in the mobilization and attenuation of heavy metals in the mine area than acid-induced dissolution. The level of concentration of trace elements for the mine spoils will serve as baseline data for future reference in the study area. 相似文献
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Adamu Mustapha Ahmad Zaharin Aris Hafizan Juahir Mohammad Firuz Ramli 《Arabian Journal of Geosciences》2013,6(12):4903-4915
The present study investigates the surface water quality of three important tributaries of Jakara Basin, northwestern Nigeria to provide an overview of the relationship and sources of physicochemical and biological parameters. A total of 405 water samples were collected from 27 sampling points and analyzed for 13 parameters: dissolved oxygen (DO), 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), suspended solids (SS), pH, ammonia-nitrogen (NH3NL), dissolved solids (DS), total solids (TS), nitrates (NO3), chloride (Cl), phosphates (PO4), Escherichia coli (E. coli) and fecal coliform bacteria (FCB). Pearson’s product–moment correlation matrix and principal component analysis (PCA) were used to distinguish the main pollution sources in the basin. Four varimax components were extracted from PCA, which explained 84.86, 83.60, and 78.69 % of the variation in the surface water quality for Jakara, Tsakama, and Gama-Kwari Rivers, respectively. Strong positive loading included BOD5, COD, NH3NL, E. coli, and FCB with negative loading on DO attribute to a domestic waste water pollution source. One-way ANOVA revealed that there was no significant difference in the mean of the three water bodies (p?>?0.05). It is therefore recommended that the government should be more effective in controlling the point source of pollution in the area. 相似文献
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Evaluation of hydrogeochemical characteristics of groundwater in parts of the lower Benue Trough, Nigeria 总被引：1，自引：0，他引：1
The aim of this work is to evaluate the hydrogeochemical characteristics of groundwater in parts of the lower Benue Through
in Nigeria as well as to evaluate the variation in groundwater chemistry data and the suitability of the groundwater for drinking
and other domestic purposes. This was based on chemical analyses of 44 water samples from existing wells and boreholes in
the study area. From the statistical analysis (wide ranges, median and standard deviation), it is obvious that there are significant
variations in the quality/composition of groundwater in the period of sampling. The calculated SAR, Na% and RSC values indicated
that the water is of excellent to good quality and is suitable for irrigation. Na and HCO3 are dominant with respect to the chemical composition of the groundwater. On the basis of water chemistry, hydrochemical
indices and factor analysis the dominant controls or processes affecting the distribution of geochemical variables in the
study area have been shown to be water/rock interaction which is mainly controlled by carbonate and silicate dissolution as
well as anthropogenic influence to a lesser extent. Additional processes include cation exchange reactions and reverse ion
exchange to a minor extent. 相似文献
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Peter Adamu Shivee Ranjanee Kaliappan Abdalla Sirag Ruth John Chenbap 《GeoJournal》2017,82(2):369-377
This study investigates the convergence of well-being between Sub Saharan Africa (SSA) and Organization for Economic Cooperation and Development (OECD) member countries during the period 1980–2014. The gap in living standard was examined from a steady state represented by the average income of OECD countries. Applying the unit root estimation technique to test for convergence with and without structural breaks, the result shows that; among a total of 43 countries studied, about 14 % are converging towards the average of OECD average. When the shock caused by the economic crisis of 2008 was factored into the analysis, the gains of about five countries out of the six converging disappeared. These results are disturbing owing to the fact that countries in the Asian region that started almost at the same level with SSA have converged to form a convergence club. Therefore, a lot more effort is needed from the government and stake holders in most countries in SSA to improve on the determinants of growth like good health care, quality institutions, better education and commitments to pursue developmental programmes which will boost the income of an average African to acquire better life. 相似文献
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