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Fish Assemblages and Fishery Analysis at the Mare aux Hippopotames in Burkina Faso
Raymond Ouedraogo,
Komandan Mano,
Desire Vogna,
Florent Marc Yabyoure Sawadogo
Issue:
Volume 10, Issue 6, December 2021
Pages:
156-164
Received:
20 September 2021
Accepted:
30 October 2021
Published:
5 November 2021
Abstract: Fish populations and the exploitation of water bodies data are essential for the implementation of sustainable fisheries management strategies. Thus, fish diversity, fisheries production and fishermen's income in the «Mare aux Hippopotames» located in western Burkina Faso were studied. This study aims to characterise the fish fauna and fisheries in this natural lake. From 12 to 16 May 2020, experimental fishing was conducted using gillnets with mesh sizes of 10, 20, 35 and 40 mm and cast-nets in five stations. Supplementary data were collected within 22 commercial fishing landings. In total, 1642 fish individuals belonging to 29 species were collected. Twenty-two genera and 13 families were identified. Sarotherodon galilaeus is the dominant species (46.83%) followed by Oreochromis niloticus (11.02%), Brycinus nurse (10.66%). The fish fauna is quite varied and reflects the characteristics of the tropical fish fauna. Length-weight relationship revealed that some fish species have allometric growth while others have isometric growth. The density of fishermen, which is between 0.18 and 0.36 fishers per hectare shows a moderate pressure on the reservoir. The total production of the lake is estimated at 47.85 tonnes per year, i.e. an average yield of 398.78 kg. ha-1. The average annual income of the fisherman is estimated at 528,000 FCFA.
Abstract: Fish populations and the exploitation of water bodies data are essential for the implementation of sustainable fisheries management strategies. Thus, fish diversity, fisheries production and fishermen's income in the «Mare aux Hippopotames» located in western Burkina Faso were studied. This study aims to characterise the fish fauna and fisheries in...
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Water Demand Investigation and Irrigation Requirement Analysis for Major Crops: A Case Study of Somodo Sub-watershed
Issue:
Volume 10, Issue 6, December 2021
Pages:
165-169
Received:
8 October 2021
Accepted:
28 October 2021
Published:
5 November 2021
Abstract: The social and economic transformations associated with growing urbanization, as well as the widespread implementation of irrigation to address climate change limits, have radically altered the pattern of water usage. The determination of water demands is the beginning point for water resource planning and management. As a result, this study was initiated with the objective of determining the various water demands in the Somodo watershed. The data employed in this investigation was secondary data. The data was population and livestock statistics gathered by the central statistical agency. Domestic water demand was calculated by multiplying the projected population number by the appropriate per capita demand, and from this, 10% of domestic water demand was adopted for industrial water demand. Water demand for livestock was estimated by multiplying the livestock population by the tropical livestock unit and the unit water requirement for each livestock. From the available water resources, 10% of the total available flow was left for the satisfaction of the environmental flow requirements. The total water demand for irrigation was estimated by multiplying the total area under irrigation with the irrigation water requirement for each cropping pattern. The total water demand for domestic and industrial water was 0.242 million cubic meters per year, according to the results. The demand for livestock water was 0.015 million cubic meters of water. The yearly environmental flow requirement was 5.6 million cubic meters (MCM), or 10% of total annual water flow. Irrigation requires a total of 0.107 million cubic meters of water.
Abstract: The social and economic transformations associated with growing urbanization, as well as the widespread implementation of irrigation to address climate change limits, have radically altered the pattern of water usage. The determination of water demands is the beginning point for water resource planning and management. As a result, this study was in...
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Hydrological and Hydraulic Analyses of Storm Water Drainage System of Enjebara Town Under the Effect of Land Use and Land Cover Change
Amare Tadesse Muche,
Yohannes Simeneh Ketsela,
Dereje Abera Ayene
Issue:
Volume 10, Issue 6, December 2021
Pages:
170-184
Received:
4 October 2021
Accepted:
4 November 2021
Published:
17 November 2021
Abstract: Urban drainage systems are desirable in all urban areas subsequently their interaction between human daily activity and natural water circulation. As the result of urban expansion and increasing surface impermeability, uncontrolled flooding from storm water drainage system has resulted in damage of small drainage channels, blockage of channels, deterioration of roads and land degradation. Hydrological analysis is thus critical to design road side drains for better management of storm water drainage. This study was conducted to evaluate hydrologic and hydraulic analyses of storm water drainage system for Enjebara town under the effect of land use land cover change. This research work included collection of both primary and secondary data. Landsat images of 1998, 2010 and 2019 for land use land cover classification were used. Geographical information system was used to prepare the classified maps and ground truth observations were also used to check the accuracy of classification. The result show that runoff volumes had increased due to land use land cover changes from 22.48% to 57.8%. In this study design of storm drainage system evaluated by using manning’s and fixing new size of reinforced concrete pipe for existing and proposed area. Bentley Civil Storm V8i dynamic storm water modeling was used to calculates and analyzes hydraulic response of existing drainage system through dependent channel, manhole and outlet to visualize flooding problems. The results obtained from hydraulic condition for storm water is flooding on the street due to peak flow generation from the catchment. According to respondent’s challenge for storm water management in Enjebara town is due to the lack of community awareness, shortage of disposing area, flooding occurrences in the street, blockage of drainage system and lack of clearance storm water drainage lines. Generally, the futures studies should conduct a more detailed study on identification of the flood causative factors to the specific location. Improve the drainage systems along Enjebara town highways, redesign storm water drainage system is essential.
Abstract: Urban drainage systems are desirable in all urban areas subsequently their interaction between human daily activity and natural water circulation. As the result of urban expansion and increasing surface impermeability, uncontrolled flooding from storm water drainage system has resulted in damage of small drainage channels, blockage of channels, det...
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Simulation of Runoff and Sediment Yield Using AnnAGNPS Model at Dawe Watershed, Eastern Hararghe, Ethiopia
Frezer Yemane,
Teshome Seyoum,
Robe Elema
Issue:
Volume 10, Issue 6, December 2021
Pages:
185-195
Received:
25 November 2021
Accepted:
25 December 2021
Published:
31 December 2021
Abstract: The high erosion rates are mainly affecting the developing countries due to intensive cultivation, deforestation; extreme climate hazard, sediment transport and loss of agricultural nutrients were caused by unwise land use practices, intensive cultivation and improper management. Soil conservation is the only known way to protect the productive land. In this study a physically based watershed model, Annualized Agricultural Non-Point Source (AnnAGNPS) pollution model was applied to the Dawe River watershed for simulation of the runoff and sediment yield. The objectives were to estimate potential runoff and sediment yield and to recommend and design appropriate soil and water conservation measures on a sub watershed basis in Dawe watershed of east hararghe zone. Sensitivity analysis, model calibration and validation were also performed. Four highly sensitive parameters were identified and of which CN was the most sensitive one. For model calibration, model efficiencies of 0.742, -231.081 and 0.828 were observed for surface runoff, peak runoff rate, and sediment yield, respectively. The corresponding determination of coefficients was 0.825, 0.1669 and 0.848, respectively. Runoff and sediment yield were well predicted but, peak runoff rate was over predicted. Validation results produced model efficiencies NSE of 0.769, -73.801 and 0.718 for surface runoff, peak runoff rate and sediment yield, respectively. With coefficient of determination (R2) of 0.9215, 0.235 and 0.764 for runoff, peak runoff rate and sediment yield, respectively. Surface runoff and sediment yield simulation were well in the validation stage and peak runoff rate shows the same trend as calibration. Dawe watershed was divided in thirteen sub-watersheds. Runoff and sediment yield for each sub-watershed were quantified. Average annual watershed runoff, average annual soil loss and total annual sediment outflow from Dawe watershed was 194.48mm, 22.467 tons/ha/yr and 354215 tons/yr, respectively. In Dawe watershed, gully, rill and inter-rill erosions were identified as major problems. Thus, check dam and bench terrace designed and vegetative waterway are recommended for intensively cultivated crop land of Dawe watershed.
Abstract: The high erosion rates are mainly affecting the developing countries due to intensive cultivation, deforestation; extreme climate hazard, sediment transport and loss of agricultural nutrients were caused by unwise land use practices, intensive cultivation and improper management. Soil conservation is the only known way to protect the productive lan...
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