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Surface Water Pollution Source Identification and Quantification: Literature Review
Mohammedsalih Kadir Gobana,
Alemayehu Haddis,
Dessalegn Dadi
Issue:
Volume 9, Issue 3, September 2023
Pages:
50-57
Received:
24 April 2023
Accepted:
10 July 2023
Published:
20 July 2023
Abstract: Surface waters are important natural resources and widely used for different purpose in human life such as agriculture, industry, municipal services and so on. Using surface water at high rate led to increasing of their pollution and scarcity. This pollution is mainly human made, in some case anthropogenic. Recognizing this problem currently, water pollution source identification and quantification is an active research area. The main objective of this review is to identify different pollution factors of surface water, approaches and methods used by different researchers for identification and quantification this pollution sources. There is different pollution factors surface water such as: heavy metal, micro plastic, nutrients like Nitrogen and phosphorus, waterborne pathogenic microbes, and petroleum hydrocarbons. Different pollution identification and quantification methods were used in different literature based on objectives and scopes of the studies. This include: Inverse Methods, Bayesian Inference, an Innovative Biosensor Network, Differential Evolution (DE) optimization algorithm, Combining Differential Evolution Algorithm (DEA) and Metropolis– Hastings–Markov Chain Monte Carlo (MH–MCMC), Field Observation and Laboratory Analysis, and Multivariate Receptor Model.
Abstract: Surface waters are important natural resources and widely used for different purpose in human life such as agriculture, industry, municipal services and so on. Using surface water at high rate led to increasing of their pollution and scarcity. This pollution is mainly human made, in some case anthropogenic. Recognizing this problem currently, water...
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Optimization of Hydropower Generation Potential of Arjo Dedessa Irrigation Dam
Issue:
Volume 9, Issue 3, September 2023
Pages:
58-68
Received:
22 June 2023
Accepted:
18 July 2023
Published:
27 July 2023
Abstract: Hydropower has been developed to have a positive impact on the quality of life for rural residents in many ways. It offers a wide range of facilities, such as improved lighting, energy for small industries, schools, computer and communication service centers, and clinics. Ethiopia has constructed numerous dams for irrigation and water supply, yet these structures may have untapped potential for other purposes. One example of such a dam is the Arjo Dedessa Irrigation Dam located in western Ethiopia. Advanced optimization models have been developed to maximize the annual energy generation from the Arjo Dedessa Dam, while taking into account restrictions on water release for irrigation and ecological purposes, as well as the need to maintain maximum reservoir yield and storage capacity. The model was analyzed using LINGO software for different probabilities of mean annual inflow exceedance. Two scenarios for hydropower retrofitting were evaluated. The scenario of independent hydropower release with reservoir inflows at 50%, 75%, and 90% probabilities of exceedance results in a total annual hydropower output of 4.8 MW, 4.34 MW, and 0.99 MW, respectively. The matching values for the scenario of complementary hydropower release were 5.27 MW, 4.55 MW, and 1 MW, respectively. The study also measured the potential increase in the reservoir's live storage capacity to 1945.01 Mm3 by utilizing flood storage, which would allow for a maximum draft increase to 285.74 Mm3. With an upper limit on storage and draft, and reservoir inflows with probabilities of exceedance at 50%, 75%, and 90%, the hydropower production increased correspondingly to 6.51 MW, 4.54 MW, and 1.935 MW for the scenario of independent hydropower release arrangement. For the scenario of complimentary hydropower release, the hydropower production improved to 6.75 MW, 4.58 MW, and 1.94 MW respectively. The outcomes specify that the Arjo Dedessa Dam is appropriate for the production of hydroelectric power and that its generation potential is between 6.51 and 6.75 MW.
Abstract: Hydropower has been developed to have a positive impact on the quality of life for rural residents in many ways. It offers a wide range of facilities, such as improved lighting, energy for small industries, schools, computer and communication service centers, and clinics. Ethiopia has constructed numerous dams for irrigation and water supply, yet t...
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Assessment of Surface Irrigation Potential Using Geospatial Technology in the Megecha River Catchment
Girma Bekele Goba,
Teshale Fita
Issue:
Volume 9, Issue 3, September 2023
Pages:
69-76
Received:
20 April 2023
Accepted:
13 July 2023
Published:
31 July 2023
Abstract: The world is suffering from different crises, like the energy crisis, food insecurity, and a basic shortage of natural resources. This study has been conducted to assess the surface irrigation suitability of the Megecha River using geospatial models. The slope gradient, soil depth, soil drainage, soil type, land use (land cover), distance from a water source, and distance of the access road were considered to assess the land's suitability for surface irrigation. After preparing each criteria map, the weight for each parameter was calculated using the analytic hierarchy process and weight overlay map analysis conducted in the GIS environment. After conducting a pair-wise comparison matrix and normalizing the pair-wise comparison matrix, slope gradient, soil type, and soil depth were weighted at 33%, 23%, and 17%, respectively. The land use and land cover change detection revealed that agriculture and built-up areas had shown significant expansion while range land was promptly decreased. The reasons for these are mainly population growth, soil fertility loss, small industries, and business company expansion. About 581.74 km2 of area is moderately suitable, but the Megecha River has the potential to irrigate only 200ha for those selected crops based on CROPWAT 8.0 analysis. Finally, I recommend that the concerned offices enhance the soil and water conservation practices in the Megecha river watershed since it is the main water source for the private sector and the local community and its land use is changing in a hydrologically negative way.
Abstract: The world is suffering from different crises, like the energy crisis, food insecurity, and a basic shortage of natural resources. This study has been conducted to assess the surface irrigation suitability of the Megecha River using geospatial models. The slope gradient, soil depth, soil drainage, soil type, land use (land cover), distance from a wa...
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Validation of Ex-Situ Runoff Harvesting in Semi-Arid Areas Using Grid-Based NRCS – CN
Kennedy Ochieng Okuku,
Japheth Ogalo Onyando,
Nancy Waithira Matheri,
Samuel Muhoro Kinyanjui
Issue:
Volume 9, Issue 3, September 2023
Pages:
77-85
Received:
7 August 2023
Accepted:
22 August 2023
Published:
31 August 2023
Abstract: Arid and Semi-Arid agroclimatic zone covers about 80% of Kenya’s land mass and supports more than 50% of the livestock and 35% of human population. Subsistence rainfed farming is key in these areas as a source of livelihood and for food security. Cases of crop failure, under rain-fed systems, due to extra and intra season drought are rampant and currently amplified by climate change. This calls for adaptive management, water smart agricultural utilization systems, in-situ and ex situ runoff harvesting for crop production. This study aimed at validating ex-situ runoff harvesting, and the use of grid based NRCS-CN integrated with GIS tools in siting water harvesting structures and quantifying the runoff in a semi-arid zone. A multi-criteria analyses was applied to the study catchment by overlaying slope, proximity to irrigable land, soil characteristics, land use and drainage pattern. A grid-based NRCS-CN model was used to evaluate the spatial distribution of event-based rainfall excess and expected runoff volume at the selected site. The estimated volume was compared to the recorded storage volume at a water pan that was installed at selected site. Based on the multi-criteria analyses a suitable site was selected and a water pan installed with a collection ditch to direct flow to the pan. The estimated spatial rainfall excess varied between 2 mm and 7 mm for a 19.6 mm event. These reflects the potential of runoff harvesting in the area. The site selection was ground validated as runoff followed the expected pattern through the collection ditch into the water pan. The estimated event-based runoff using CN method was representative as these was reflected in recorded volume of run off harvested by the water pan. The grid based NRCS-CN integrated GIS model is proved as an effective tool for siting runoff harvesting structures and estimating the expected runoff volume.
Abstract: Arid and Semi-Arid agroclimatic zone covers about 80% of Kenya’s land mass and supports more than 50% of the livestock and 35% of human population. Subsistence rainfed farming is key in these areas as a source of livelihood and for food security. Cases of crop failure, under rain-fed systems, due to extra and intra season drought are rampant and cu...
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