A class of Ruscheweyh – type harmonic functions associated with both sigmoid function and probabilities of the generalized distribution series is defined using differential operators. We then establish properties of the class such as coefficient estimate, distortion theorem, extreme point, and convex combination condition. Several applications of our results are obtained as corollaries by varying various parameters involved.
{"title":"Ruscheweyh – Type Harmonic Functions Associated with Probabilities of the Generalized Distribution and Sigmoid Function Defined by q- differential Operators","authors":"Awolere Ibrahim Taiwo, Oyekan Ezekiel Abiodun","doi":"10.4314/mejs.v13i2.1","DOIUrl":"https://doi.org/10.4314/mejs.v13i2.1","url":null,"abstract":"A class of Ruscheweyh – type harmonic functions associated with both sigmoid function and probabilities of the generalized distribution series is defined using differential operators. We then establish properties of the class such as coefficient estimate, distortion theorem, extreme point, and convex combination condition. Several applications of our results are obtained as corollaries by varying various parameters involved.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42565822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The paper was aimed at examining the relationship between the distribution of public primary and secondary schools and the population in Kaduna State. The study used GPS Map 78 to ascertain the location of the schools through field observation. The student population was obtained from the headteacher while the population was obtained from the projected 2006 census figure. A multistage sampling method was adopted to select nine LGAs within the three senatorial zones of the state. Descriptive statistics using Statistical Package for the Social Sciences (v25), Spearman Rank Correlation, and Pearson Correlation was used for data analysis. The 1907 public schools (1634 public primary and 273 secondary schools) were found. The result revealed that the overall Location Quotient (LQ) value for all public schools (primary, junior and secondary schools) is 1.14 which represents a moderate concentration of public schools. The result showed that Kaduna South LGA has the least LQ (0.23) and is closely followed by Zaria LGA (0.56), while Kajuru LGA has the most concentration of schools with an LQ of 2.2. The result also revealed that LQ for Junior Secondary Schools (JSS) value varies from (1.9) in Kagarko LGA, having the highest concentration of JSS and to 0.5 in Jemaá LGA The Spearman Rank Correlation with the coefficient of 0.188 revealed a weak positive relationship between the provision of public schools and students’ population while Pearson Correlation established a negative relationship between the distribution of public schools and general population with the coefficient of -0.19. The study concluded that there is no relationship between the population and distribution of public schools in Kaduna State.
{"title":"Analysis of the Relationship between Public Schools Distribution and Population in Kaduna State, Nigeria","authors":"Ezeamaka Cyril Kanayochukwu","doi":"10.4314/mejs.v13i2.4","DOIUrl":"https://doi.org/10.4314/mejs.v13i2.4","url":null,"abstract":"The paper was aimed at examining the relationship between the distribution of public primary and secondary schools and the population in Kaduna State. The study used GPS Map 78 to ascertain the location of the schools through field observation. The student population was obtained from the headteacher while the population was obtained from the projected 2006 census figure. A multistage sampling method was adopted to select nine LGAs within the three senatorial zones of the state. Descriptive statistics using Statistical Package for the Social Sciences (v25), Spearman Rank Correlation, and Pearson Correlation was used for data analysis. The 1907 public schools (1634 public primary and 273 secondary schools) were found. The result revealed that the overall Location Quotient (LQ) value for all public schools (primary, junior and secondary schools) is 1.14 which represents a moderate concentration of public schools. The result showed that Kaduna South LGA has the least LQ (0.23) and is closely followed by Zaria LGA (0.56), while Kajuru LGA has the most concentration of schools with an LQ of 2.2. The result also revealed that LQ for Junior Secondary Schools (JSS) value varies from (1.9) in Kagarko LGA, having the highest concentration of JSS and to 0.5 in Jemaá LGA The Spearman Rank Correlation with the coefficient of 0.188 revealed a weak positive relationship between the provision of public schools and students’ population while Pearson Correlation established a negative relationship between the distribution of public schools and general population with the coefficient of -0.19. The study concluded that there is no relationship between the population and distribution of public schools in Kaduna State. \u0000 \u0000 ","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47211184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tree height is a parameter useful for calculating above-ground forest biomass and is mostly measured traditionally by ground survey. On the other hand, measuring the forest tree height and biomass estimation through field survey is labor-intensive and time-consuming. The application of remote sensing for forest above-ground biomass (AGB) estimation without forest destruction is important in order to estimate the carbon sequestration potential of the forest. The unmanned aerial vehicle (UAV) is an elating technology, which can help to estimate tree height and it is evolving at a rapid speed. Moreover, assessing the relationship between estimated and measured tree height is necessary for the future application of estimated tree height on AGB estimation. However, tree height estimation from photogrammetric UAV imagery in the dry Afromontane Forest and its sensitivity to AGB estimation are not investigated. Thus, this study aimed to assess the accuracy of tree height estimated from photogrammetric UAV imagery and the sensitivity of the estimated tree height on AGB estimation. Photogrammetric UAV acquired images and sample trees height measured on the ground were collected in Desa’a dry Afromontane Forest, Northern Ethiopia. Tree height was estimated from photogrammetric UAV acquired images and compared with tree heights measured on the ground. Moreover, the sensitivity of the estimated tree height on AGB estimation was investigated. The estimated tree height explained 89% of the tree height measured in the field. A considerable difference between estimated and measured tree height has an insignificant effect on AGB estimation. Thus, in the dry land Afromontane Forest the application of UAV aerial imagery for tree height estimation is promising to estimate AGB.
{"title":"Tree Height Estimation from Unmanned Aerial Vehicle Imagery and Its Sensitivity on Above Ground Biomass Estimation in Dry Afromontane Forest, Northern Ethiopia","authors":"Tigistu Hadush, Atkilt Girma, A. Zenebe","doi":"10.4314/mejs.v13i2.5","DOIUrl":"https://doi.org/10.4314/mejs.v13i2.5","url":null,"abstract":"Tree height is a parameter useful for calculating above-ground forest biomass and is mostly measured traditionally by ground survey. On the other hand, measuring the forest tree height and biomass estimation through field survey is labor-intensive and time-consuming. The application of remote sensing for forest above-ground biomass (AGB) estimation without forest destruction is important in order to estimate the carbon sequestration potential of the forest. The unmanned aerial vehicle (UAV) is an elating technology, which can help to estimate tree height and it is evolving at a rapid speed. Moreover, assessing the relationship between estimated and measured tree height is necessary for the future application of estimated tree height on AGB estimation. However, tree height estimation from photogrammetric UAV imagery in the dry Afromontane Forest and its sensitivity to AGB estimation are not investigated. Thus, this study aimed to assess the accuracy of tree height estimated from photogrammetric UAV imagery and the sensitivity of the estimated tree height on AGB estimation. Photogrammetric UAV acquired images and sample trees height measured on the ground were collected in Desa’a dry Afromontane Forest, Northern Ethiopia. Tree height was estimated from photogrammetric UAV acquired images and compared with tree heights measured on the ground. Moreover, the sensitivity of the estimated tree height on AGB estimation was investigated. The estimated tree height explained 89% of the tree height measured in the field. A considerable difference between estimated and measured tree height has an insignificant effect on AGB estimation. Thus, in the dry land Afromontane Forest the application of UAV aerial imagery for tree height estimation is promising to estimate AGB. \u0000 \u0000 ","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45142830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Brhanemeskel Weleabzgi, T. Alemayehu, Samual Estifanos
The paper presents the environmental impact of artisanal gold mining activities on the waters and sediments around Meli, northwestern Tigray, Ethiopia. Stream sediment, water, and tailing samples were collected in the dry season in January of 2019 and analyzed for heavy metals Cu, Zn, Pb, and As. The physicochemical parameters (pH, EC, major cations, and anions) of a few water samples were also measured. Flame atomic absorption spectrometry was used to determine the level of the metals in stream sediments. The results show that tailing has the highest concentration of metals followed by the stream sediments. The least concentrations are recorded in water for all metals. Pb has the highest mean concentration of all heavy metals in stream sediments, waters, and tailing samples. The mean Geo-accumulation Index (Igeo) and Contamination Factor (CF) suggest that the sediment represents uncontaminated to moderately contaminated classes. Concentrations of Cu and Zn in the water samples are generally within the maximum allowable concentration of the WHO, whereas concentrations of Pb and As are above the limit. Metal Index for surface and groundwater suggests that the area is polluted with heavy metals Pb and As. The main sources of the metals are assumed to be the sulfide ores facilitated by natural weathering processes and artisanal mining activities like excavations, crushing, grinding, and amalgamation processes. The Gibbs and Durov plots show that major hydrogeochemical processes controlling the water chemistry are water-rock interactions with considerable mixing of water types.
{"title":"Assessing the Environmental Impact of Artisanal Gold Mining Activities on the Waters and Sediments Around Meli, Northwestern Tigray, Ethiopia","authors":"Brhanemeskel Weleabzgi, T. Alemayehu, Samual Estifanos","doi":"10.4314/mejs.v13i2.6","DOIUrl":"https://doi.org/10.4314/mejs.v13i2.6","url":null,"abstract":"The paper presents the environmental impact of artisanal gold mining activities on the waters and sediments around Meli, northwestern Tigray, Ethiopia. Stream sediment, water, and tailing samples were collected in the dry season in January of 2019 and analyzed for heavy metals Cu, Zn, Pb, and As. The physicochemical parameters (pH, EC, major cations, and anions) of a few water samples were also measured. Flame atomic absorption spectrometry was used to determine the level of the metals in stream sediments. The results show that tailing has the highest concentration of metals followed by the stream sediments. The least concentrations are recorded in water for all metals. Pb has the highest mean concentration of all heavy metals in stream sediments, waters, and tailing samples. The mean Geo-accumulation Index (Igeo) and Contamination Factor (CF) suggest that the sediment represents uncontaminated to moderately contaminated classes. Concentrations of Cu and Zn in the water samples are generally within the maximum allowable concentration of the WHO, whereas concentrations of Pb and As are above the limit. Metal Index for surface and groundwater suggests that the area is polluted with heavy metals Pb and As. The main sources of the metals are assumed to be the sulfide ores facilitated by natural weathering processes and artisanal mining activities like excavations, crushing, grinding, and amalgamation processes. The Gibbs and Durov plots show that major hydrogeochemical processes controlling the water chemistry are water-rock interactions with considerable mixing of water types. \u0000 \u0000 ","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42340565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abdelwassie Hussien, Tesfamichael Gebreyohannes, M. Hagos, G. Berhane, K. Amare, G. Zenebe
Due to the ever-increasing demand for water in Aynalem catchment and its surrounding, there has been an increased pressure on the Aynalem well field putting the sustainability of water supply from the aquifer under continuous threat. Thus, it is vital to understand the water balance of the catchment to ensure sustainable utilization of the groundwater resource. This in turn requires proper quantification of the components of water balance among which recharge estimation is the most important. This paper estimates the groundwater recharge of the Aynalem catchment using high-resolution hydro-meteorological data. Daily precipitation and temperature measurement data for years 2001-2018; groundwater level fluctuation records collected at every 30 minutes; and soil and land use maps were used to make recharge estimations. In the groundwater level fluctuation, three boreholes were monitored, but only two were utilized for the analysis because the third was under operation and does not represent the natural hydrologic condition. Thornthwaite soil moisture balance and groundwater level fluctuation methods were applied to determine the groundwater recharge of the Aynalem catchment. Accordingly, the annual rate of groundwater recharge estimated based on the soil-water balance ranges between 7mm/year and 138.5 mm/year with the weighted average value of 89.04 mm/year. The weighted average value is considered to represent the catchment value because the diverse soil and land use/cover types respond differently to allow the precipitation to recharge the groundwater. On the other hand, the groundwater recharge estimated using the groundwater level fluctuation method showed yearly groundwater recharge of 91 to 93 mm/year. The similarity in the groundwater recharge result obtained from both methods strengthens the acceptability of the estimate. It also points out that the previously reported estimate is much lower (36 to 66 mm/year).
{"title":"High-resolution Data Based Groundwater Recharge Estimations of Aynalem Well Field","authors":"Abdelwassie Hussien, Tesfamichael Gebreyohannes, M. Hagos, G. Berhane, K. Amare, G. Zenebe","doi":"10.4314/mejs.v13i1.1","DOIUrl":"https://doi.org/10.4314/mejs.v13i1.1","url":null,"abstract":"Due to the ever-increasing demand for water in Aynalem catchment and its surrounding, there has been an increased pressure on the Aynalem well field putting the sustainability of water supply from the aquifer under continuous threat. Thus, it is vital to understand the water balance of the catchment to ensure sustainable utilization of the groundwater resource. This in turn requires proper quantification of the components of water balance among which recharge estimation is the most important. This paper estimates the groundwater recharge of the Aynalem catchment using high-resolution hydro-meteorological data. Daily precipitation and temperature measurement data for years 2001-2018; groundwater level fluctuation records collected at every 30 minutes; and soil and land use maps were used to make recharge estimations. In the groundwater level fluctuation, three boreholes were monitored, but only two were utilized for the analysis because the third was under operation and does not represent the natural hydrologic condition. Thornthwaite soil moisture balance and groundwater level fluctuation methods were applied to determine the groundwater recharge of the Aynalem catchment. Accordingly, the annual rate of groundwater recharge estimated based on the soil-water balance ranges between 7mm/year and 138.5 mm/year with the weighted average value of 89.04 mm/year. The weighted average value is considered to represent the catchment value because the diverse soil and land use/cover types respond differently to allow the precipitation to recharge the groundwater. On the other hand, the groundwater recharge estimated using the groundwater level fluctuation method showed yearly groundwater recharge of 91 to 93 mm/year. The similarity in the groundwater recharge result obtained from both methods strengthens the acceptability of the estimate. It also points out that the previously reported estimate is much lower (36 to 66 mm/year).","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46018945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper deals with the results of a pilot study conducted to estimate the shallow groundwater resource potential and irrigation capacity at the household level in Tahtay Koraro Woreda, northwestern zone of Tigray, Ethiopia. The potential evapotranspiration and actual evapotranspiration of the study area are estimated to be 1484 mm/year and 814 mm/year respectively. The runoff is approximately calculated to be 280 mm/year and the annual groundwater recharge is estimated to be 29 mm/year. The total annual groundwater abstraction for human, livestock, and irrigation is estimated to be 25 mm/year. It should be noted that the groundwater recharge rate is expected to remain constant while the total annual groundwater discharge is expected to increase from year to year. This relation when projected over a long period may result in a negative groundwater budget which can result in depletion of groundwater (lowering of groundwater levels), reduced baseflow to streams, and deterioration of water quality. The computed values for hydraulic conductivity of the aquifers range from 1.63 m/day to 7.27 m/day with an average value of 4.9 m/day and transmissivity from 48.9 m2/day to 218.1 m2/day with an average value of 147.14 m2/day. The aquifers in the highly weathered basalt and highly weathered siltstone – sandstone intercalation have transmissivity values ranging from 99 m2/day to 218.1 m2/day with an average value of 157 m2/day and are grouped into the moderate potentiality aquifers category. The aquifers in the slightly weathered and fractured metavolcanics grouped under low potentiality based on the lower transmissivity values (<50 m2/day). The study area has low to moderate groundwater potentiality, hence, large-scale groundwater pumping is not possible. Therefore, the current activity of using hand dug wells for household-level irrigation is the best way of using groundwater for irrigation and other uses as well. Increasing the depth of the existing hand dug wells that are constructed in highly weathered basalt and highly weathered siltstone – sandstone intercalation can also enhance the yield of the hand dug wells. It is recommended to use water-saving irrigation technologies rather than increasing the number of wells. This will also help in increasing the irrigation area. Groundwater recharge enhancement structures such as trenches, percolation ponds, and check dams be constructed in scientifically selected localities to further enhance the groundwater potential.
{"title":"Potential of Shallow Groundwater for Household Level Irrigation Practices in Tahtay Koraro Woreda, Tigray, Northern Ethiopia","authors":"Ermias Hagos, Amare Girmay, Tesfamichael Gebreyohannes","doi":"10.4314/mejs.v13i1.3","DOIUrl":"https://doi.org/10.4314/mejs.v13i1.3","url":null,"abstract":"This paper deals with the results of a pilot study conducted to estimate the shallow groundwater resource potential and irrigation capacity at the household level in Tahtay Koraro Woreda, northwestern zone of Tigray, Ethiopia. The potential evapotranspiration and actual evapotranspiration of the study area are estimated to be 1484 mm/year and 814 mm/year respectively. The runoff is approximately calculated to be 280 mm/year and the annual groundwater recharge is estimated to be 29 mm/year. The total annual groundwater abstraction for human, livestock, and irrigation is estimated to be 25 mm/year. It should be noted that the groundwater recharge rate is expected to remain constant while the total annual groundwater discharge is expected to increase from year to year. This relation when projected over a long period may result in a negative groundwater budget which can result in depletion of groundwater (lowering of groundwater levels), reduced baseflow to streams, and deterioration of water quality. The computed values for hydraulic conductivity of the aquifers range from 1.63 m/day to 7.27 m/day with an average value of 4.9 m/day and transmissivity from 48.9 m2/day to 218.1 m2/day with an average value of 147.14 m2/day. The aquifers in the highly weathered basalt and highly weathered siltstone – sandstone intercalation have transmissivity values ranging from 99 m2/day to 218.1 m2/day with an average value of 157 m2/day and are grouped into the moderate potentiality aquifers category. The aquifers in the slightly weathered and fractured metavolcanics grouped under low potentiality based on the lower transmissivity values (<50 m2/day). The study area has low to moderate groundwater potentiality, hence, large-scale groundwater pumping is not possible. Therefore, the current activity of using hand dug wells for household-level irrigation is the best way of using groundwater for irrigation and other uses as well. Increasing the depth of the existing hand dug wells that are constructed in highly weathered basalt and highly weathered siltstone – sandstone intercalation can also enhance the yield of the hand dug wells. It is recommended to use water-saving irrigation technologies rather than increasing the number of wells. This will also help in increasing the irrigation area. Groundwater recharge enhancement structures such as trenches, percolation ponds, and check dams be constructed in scientifically selected localities to further enhance the groundwater potential.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46402962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Berihu Abadi Berhe, Fethangest Woldemariyam Tesema, G. Mebrahtu
The study area, Kombolcha town, forms an important industrial town situated in the Eastern Amhara region, Ethiopia. The geology of the area is mainly composed of basalts, rhyolitic ignimbrites, and Quaternary sediments. Hydrogeochemistry and the source of ions in the groundwater of the study area are poorly understood. Therefore, the current study aims to assess the factors and the different hydrochemical processes significantly controlling groundwater quality, source, and chemistry. For this purpose, a total of eighteen groundwater samples were collected using 250 ml sampling bottles at selected points in the dry season (May 2017) and wet season (November 2017). Gibbs diagram, correlation analysis, scatter plots of ionic molar ratio relations, saturation index values (estimated using PHREEQC Interactive 2.8) were used to decipher the hydrogeochemical process. Gibbs diagram shows that the rock-water interaction process is the predominant, Na+/Cl- and Ca2+/Mg2+ molar ratio value of all groundwater samples in both seasons reveals that the groundwater chemistry of the area is controlled by silicate minerals weathering. The strong correlation of Ca2+ with Mg2+ in the dry season, and Ca2+ with HCO3- and Na+ with HCO3- in the wet season could also be an indication of silicate weathering and ion exchange processes. The impact of anthropogenic practices on groundwater chemistry is also seen from the strong correlation of Ca2+ with Cl-, NO3-, PO43- and F-, NO2- with K+, Mg2+, and PO43- , PO43- with F- , and NO3- with Na+, Cl-, HCO3- . The negative values of chloro-alkaline indices in both seasons indicate base-exchange reaction where an indirect exchange of Ca2+ and Mg2+ of the water with Na+ and K+ of the host rock occurs. Saturation indices results for the wet season show that the groundwater is under-saturated with respect to calcite, aragonite, dolomite, gypsum, and anhydrite. In the dry season, however, some of the waters are oversaturated with respect to calcite and aragonite. To sum up, the groundwater quality of the study area is controlled by geological processes and anthropogenic effects.
{"title":"Assessment of Major Sources Controlling Groundwater Chemistry in Kombolcha Plain, Eastern Amhara Region, Ethiopia","authors":"Berihu Abadi Berhe, Fethangest Woldemariyam Tesema, G. Mebrahtu","doi":"10.4314/mejs.v13i1.2","DOIUrl":"https://doi.org/10.4314/mejs.v13i1.2","url":null,"abstract":"The study area, Kombolcha town, forms an important industrial town situated in the Eastern Amhara region, Ethiopia. The geology of the area is mainly composed of basalts, rhyolitic ignimbrites, and Quaternary sediments. Hydrogeochemistry and the source of ions in the groundwater of the study area are poorly understood. Therefore, the current study aims to assess the factors and the different hydrochemical processes significantly controlling groundwater quality, source, and chemistry. For this purpose, a total of eighteen groundwater samples were collected using 250 ml sampling bottles at selected points in the dry season (May 2017) and wet season (November 2017). Gibbs diagram, correlation analysis, scatter plots of ionic molar ratio relations, saturation index values (estimated using PHREEQC Interactive 2.8) were used to decipher the hydrogeochemical process. Gibbs diagram shows that the rock-water interaction process is the predominant, Na+/Cl- and Ca2+/Mg2+ molar ratio value of all groundwater samples in both seasons reveals that the groundwater chemistry of the area is controlled by silicate minerals weathering. The strong correlation of Ca2+ with Mg2+ in the dry season, and Ca2+ with HCO3- and Na+ with HCO3- in the wet season could also be an indication of silicate weathering and ion exchange processes. The impact of anthropogenic practices on groundwater chemistry is also seen from the strong correlation of Ca2+ with Cl-, NO3-, PO43- and F-, NO2- with K+, Mg2+, and PO43- , PO43- with F- , and NO3- with Na+, Cl-, HCO3- . The negative values of chloro-alkaline indices in both seasons indicate base-exchange reaction where an indirect exchange of Ca2+ and Mg2+ of the water with Na+ and K+ of the host rock occurs. Saturation indices results for the wet season show that the groundwater is under-saturated with respect to calcite, aragonite, dolomite, gypsum, and anhydrite. In the dry season, however, some of the waters are oversaturated with respect to calcite and aragonite. To sum up, the groundwater quality of the study area is controlled by geological processes and anthropogenic effects.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47168340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Almost 100% of the water supply of Dire Dawa City is from groundwater (including boreholes, dug wells, and springs). Recently, groundwater cause corrosion and scale problems to water distribution systems due to its content of dissolved ions that can cause public health and economic issues. The present paper investigates the corrosion and scale-forming potential of the groundwater in the city and visualizes it with mapping. Spectrophotometer, EDTA/Acid titration with calculation methods were used for water quality parameters analysis. GW Chart Calibration plot applied for the Piper diagram to categorizes the water types. Langelier saturation (LSI), Ryznar (RSI), aggressive (AI), Puckorius Scale (PSI), and Larson-Skold (LRI) indices were manipulated with Excel ® and visualized their spatial distribution using ArcGIS 10®. The mean values of LSI, RSI, PSI, AI, and LRI obtained were 0.29 ± 0.28, 6.4 ± 0.5, 5.10 ± 0.48, 12.20 ± 0.24, and 1.4±1.57 respectively. LSI and RSI results indicate moderate to low scale-forming tendency of groundwater in most parts except the northeastern part with corrosive groundwater. Based on the AI value, the groundwater ranges low corrosion in almost all zones except the edge of the northeast and northwest region. PSI indicated the water tends to form salt-scale at a medium rate. The LSI results showed that chloride and sulphate are unlikely to interfere with the formation of protecting film except in northwestern and northeastern regions where localized corrosion might occur. In conclusion, in almost all distribution system of the city is affected by calcium carbonate scale formation. The groundwater in the northwest and northeast resulted in localized corrosion because of relatively high contents of chlorides and sulphates.
{"title":"Assessment of Corrosion and Scale forming Potential of Groundwater Resources: Case Study of Dire Dawa City, Ethiopia","authors":"Girmaye Haile Gebremikael, Aman Hussien Dawod","doi":"10.4314/mejs.v13i1.6","DOIUrl":"https://doi.org/10.4314/mejs.v13i1.6","url":null,"abstract":"Almost 100% of the water supply of Dire Dawa City is from groundwater (including boreholes, dug wells, and springs). Recently, groundwater cause corrosion and scale problems to water distribution systems due to its content of dissolved ions that can cause public health and economic issues. The present paper investigates the corrosion and scale-forming potential of the groundwater in the city and visualizes it with mapping. Spectrophotometer, EDTA/Acid titration with calculation methods were used for water quality parameters analysis. GW Chart Calibration plot applied for the Piper diagram to categorizes the water types. Langelier saturation (LSI), Ryznar (RSI), aggressive (AI), Puckorius Scale (PSI), and Larson-Skold (LRI) indices were manipulated with Excel ® and visualized their spatial distribution using ArcGIS 10®. The mean values of LSI, RSI, PSI, AI, and LRI obtained were 0.29 ± 0.28, 6.4 ± 0.5, 5.10 ± 0.48, 12.20 ± 0.24, and 1.4±1.57 respectively. LSI and RSI results indicate moderate to low scale-forming tendency of groundwater in most parts except the northeastern part with corrosive groundwater. Based on the AI value, the groundwater ranges low corrosion in almost all zones except the edge of the northeast and northwest region. PSI indicated the water tends to form salt-scale at a medium rate. The LSI results showed that chloride and sulphate are unlikely to interfere with the formation of protecting film except in northwestern and northeastern regions where localized corrosion might occur. In conclusion, in almost all distribution system of the city is affected by calcium carbonate scale formation. The groundwater in the northwest and northeast resulted in localized corrosion because of relatively high contents of chlorides and sulphates.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42951045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The mining sector’s share in Ethiopia’s economy is gradually increasing. Among metallic mines, Legadembi for gold and Kenticha for tantalum are the main contributors. At Kenticha, the Ethiopian Mineral Development Share Company is producing tantalite concentrate of 40-60% grade by open pit mining. The mine area is comprised of the rocks of Neoproterozoic age, pegmatite, granite, serpentinite, and talc-chlorite schist. The ore-bearing pegmatite intruding the basement serpentinite, and talc schist rocks, is asymmetric, N-S trending, and locally affected by fractures and local faults. Mining, at present, is being done using conventional methods not by developing benches. An optimum open pit design is developed and its impact on the run of mine is evaluated based on the field data, technical mine report data, borehole data, tonnage data, grade data, and mine survey. The suggested design has taken into account the mine drainage, bench design, haul road design, and mine waste dump design. Also keeping in view the future mining and production requirements. The suggested open pit mine design can minimize the dilution and improve the ore recovery.
{"title":"Optimum Open Pit Design for Kenticha Tantalite Mine, Southern Ethiopia","authors":"Weldegebrial Haile, B. Konka","doi":"10.4314/mejs.v13i1.8","DOIUrl":"https://doi.org/10.4314/mejs.v13i1.8","url":null,"abstract":"The mining sector’s share in Ethiopia’s economy is gradually increasing. Among metallic mines, Legadembi for gold and Kenticha for tantalum are the main contributors. At Kenticha, the Ethiopian Mineral Development Share Company is producing tantalite concentrate of 40-60% grade by open pit mining. The mine area is comprised of the rocks of Neoproterozoic age, pegmatite, granite, serpentinite, and talc-chlorite schist. The ore-bearing pegmatite intruding the basement serpentinite, and talc schist rocks, is asymmetric, N-S trending, and locally affected by fractures and local faults. Mining, at present, is being done using conventional methods not by developing benches. An optimum open pit design is developed and its impact on the run of mine is evaluated based on the field data, technical mine report data, borehole data, tonnage data, grade data, and mine survey. The suggested design has taken into account the mine drainage, bench design, haul road design, and mine waste dump design. Also keeping in view the future mining and production requirements. The suggested open pit mine design can minimize the dilution and improve the ore recovery.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47502880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A substantial share of the total energy in various countries is consumed by industries and manufacturing sectors. Most of the energy is used for low and medium temperature process heating (up to 300 degrees C) as well as low and medium cooling capacity (up to 350kW). To meet the demand, the industrial sector consumes most of its energy in either thermal (heat) or electrical energy forms. The use of fossil fuels accounts for about half of the overall share. This resulted in a necessity to commercialize local and clean renewable energy sources efficiently considering the reduction of economic dependence on fossil fuels and greenhouse gases emission. As such, solar energy has proven potential and resulted in considerable development and deployment of solar heating industrial processes (SHIP) and solar cooling systems in recent times. Thus, an attempt to present a review of the available literature on overall energy intensiveness, process temperature levels, solar technology match, and solar thermal system performance and cost have been made in this paper. The review also includes identifying the potential and relevance of involving solar thermal for industrial heating and cooling demand. As a result, at least 624 SHIP including promising large-scale plants and 1350 solar cooling systems most of them in small and medium capacities in operation are identified. Though limited data is available for solar cooling potential and installation, investigations projected the global SHIP potential to 5.6 EJ for 2050. Consequently, given the presence of many low and medium temperature heating processes and cooling capacities in industries with immense solar energy potential, developing counties such as Ethiopia can take experience and pay attention to the development of sustainable industrial systems.
{"title":"A Review on Solar Thermal Utilization for Industrial Heating and Cooling Processes: Global and Ethiopian Perspective","authors":"Yacob Gebreyohannes, M. Bayray, J. Lauwaert","doi":"10.4314/MEJS.V12I2.6","DOIUrl":"https://doi.org/10.4314/MEJS.V12I2.6","url":null,"abstract":"A substantial share of the total energy in various countries is consumed by industries and manufacturing sectors. Most of the energy is used for low and medium temperature process heating (up to 300 degrees C) as well as low and medium cooling capacity (up to 350kW). To meet the demand, the industrial sector consumes most of its energy in either thermal (heat) or electrical energy forms. The use of fossil fuels accounts for about half of the overall share. This resulted in a necessity to commercialize local and clean renewable energy sources efficiently considering the reduction of economic dependence on fossil fuels and greenhouse gases emission. As such, solar energy has proven potential and resulted in considerable development and deployment of solar heating industrial processes (SHIP) and solar cooling systems in recent times. Thus, an attempt to present a review of the available literature on overall energy intensiveness, process temperature levels, solar technology match, and solar thermal system performance and cost have been made in this paper. The review also includes identifying the potential and relevance of involving solar thermal for industrial heating and cooling demand. As a result, at least 624 SHIP including promising large-scale plants and 1350 solar cooling systems most of them in small and medium capacities in operation are identified. Though limited data is available for solar cooling potential and installation, investigations projected the global SHIP potential to 5.6 EJ for 2050. Consequently, given the presence of many low and medium temperature heating processes and cooling capacities in industries with immense solar energy potential, developing counties such as Ethiopia can take experience and pay attention to the development of sustainable industrial systems.","PeriodicalId":18948,"journal":{"name":"Momona Ethiopian Journal of Science","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2021-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48834018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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