Pub Date : 2020-01-21DOI: 10.4236/ojmh.2020.101001
O. Al-Khashman, H. Alnawafleh
The study was undertaken to assess the physicochemical and chemical quality of the Tannur dam water in southern Jordan. The water samples were collected in two intervals the first during May 2015 and the second during September 2015. All samples were analyzed for temperature, conductivity, dissolved oxygen, pH, major cations (Ca2+, Mg2+, K+, Na+), and major anions (Cl-, NO3-, HCO3- and SO42-). The hydrogeochemical analyses of thirty-six water samples were used to determine the properties and type of water in the Tannur dam. The ion concentration in the water samples was from dissolution of carbonate rocks and ion exchange processes in clay. The general chemistry of water samples was typical alkaline earth waters with prevailing bicarbonate chloride. The PHREEQC Hydrogeochemical modeling was used to obtain the saturation indices of specific mineral phases, which might be related to interaction with water and aquifer, and to identify the chemical species of the dissolved ions. Calcite and dolomite solubility were assessed in terms of saturation index where they show positive values indication oversaturated SI > 0. The hydrogeochemistry behavior is rather complicated and is affected by anthropogenic and natural sources. The positive correlation values between various parameters indicate that most of ions result from same lithological sources. The abundance of the major ions in water samples is in the following order: HCO3-> Ca2+ > Cl- > NO3- > SO42-) > Na+ > Mg2+ > K+. Water samples of the Tannur dam are generally very hard, high to very high saline and medium alkaline in nature. High total hardness (TH) and total dissolved solids (TDS) in some samples identify the permissible for domestic and irrigation purposes. According to the residual sodium carbonate, SAR and conductivity values, the studied water is suitable for agricultural purposes.
{"title":"Hydrochemistry and Quality Assessment of Water in Tannur Dam, Southern Jordan","authors":"O. Al-Khashman, H. Alnawafleh","doi":"10.4236/ojmh.2020.101001","DOIUrl":"https://doi.org/10.4236/ojmh.2020.101001","url":null,"abstract":"The study was undertaken to assess the physicochemical \u0000and chemical quality of the Tannur dam water in southern Jordan. The water \u0000samples were collected in two intervals the first during May 2015 and the \u0000second during September 2015. All samples were analyzed for temperature, \u0000conductivity, dissolved oxygen, pH, major cations (Ca2+, Mg2+, \u0000K+, Na+), and major anions \u0000(Cl-, NO3-, HCO3- and SO42-). The \u0000hydrogeochemical analyses of thirty-six water samples were used to determine \u0000the properties and type of water in the Tannur dam. The ion concentration in \u0000the water samples was from dissolution of carbonate rocks and ion exchange \u0000processes in clay. The general chemistry of water samples was typical alkaline \u0000earth waters with prevailing bicarbonate chloride. The PHREEQC Hydrogeochemical \u0000modeling was used to obtain the saturation indices of specific mineral phases, \u0000which might be related to interaction with water and aquifer, and to identify \u0000the chemical species of the dissolved ions. Calcite and dolomite solubility \u0000were assessed in terms of saturation index where they show positive values \u0000indication oversaturated SI > 0. The hydrogeochemistry behavior is rather \u0000complicated and is affected by anthropogenic and natural sources. The positive correlation \u0000values between various parameters indicate that most of ions result from same \u0000lithological sources. The abundance of the major ions in water samples is in \u0000the following order: HCO3-> Ca2+ > Cl- > NO3- > SO42-) > Na+ > Mg2+ > K+. Water samples of the Tannur dam are \u0000generally very hard, high to very high saline and medium alkaline in nature. \u0000High total hardness (TH) and total dissolved solids (TDS) in some samples \u0000identify the permissible for domestic and irrigation purposes. According to the \u0000residual sodium carbonate, SAR and conductivity values, the studied water is \u0000suitable for agricultural purposes.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42001071","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}
Pub Date : 2020-01-01DOI: 10.4236/ojmh.2020.103004
R. Diédhiou, S. Sambou, Seïdou Kane, Issa Lèye, S. Diatta, Moussé Landing Sane, D. Ndione
The Sahelian regions have experienced a drought that has made them vulnerable to hydro-climatic conditions. Strategies have been developed to reduce this vulnerability. The governments of Senegal, Mauritania, Mali and Guinea have created the Organization for the development of the Senegal River (OMVS in french) with the aim of realizing large hydraulic installations. This resulted in the construction of the Diama and Manantali dams in the Senegal River Basin. The first aims to stop the saline intrusion, the second to regulate the flow of the river, to allow the irrigation of agricultural perimeters, and to produce electrical energy. The impoundment of the Diama dam has modified the hydraulic behavior of the estuary. The purpose of this study is to carry out the hydraulic modeling of the estuary of Senegal river downstream of the Diama Dam in transient mode by the HEC-RAS software. Two geometric models were constructed on the basis of a digital terrain model (DTM) using the Arc-GIS and HEC GeoRAS soft wares after processing the collected topographic data. The first geometric model, of which the areas of Senegal river downstream Diama Dam have been represented by cross-section, is one-dimensional. The second one is also one dimensional; in this model, the area of the Senegal River estuary downstream Diama Dam is introduced as water storage zones. The components of these models are the stream sections, lateral links, and storage areas. The flood hydrograph downstream Diama Dam is introduced as conditions at the upstream limits of the models while the tidal is introduced as a downstream condition. After the stability and calibration, the results given by HEC-RAS simulations are the variations of the water levels, the temporal variations of the flow rates for each section, the maximum flow velocities and the propagation times of the flood waves. The analysis and comparisons of these results strongly suggest using HEC-RAS issues as a decision-making tool helping to manage floods during times of crisis.
{"title":"Calibration of HEC-RAS Model for One Dimensional Steady Flow Analysis—A Case of Senegal River Estuary Downstream Diama Dam","authors":"R. Diédhiou, S. Sambou, Seïdou Kane, Issa Lèye, S. Diatta, Moussé Landing Sane, D. Ndione","doi":"10.4236/ojmh.2020.103004","DOIUrl":"https://doi.org/10.4236/ojmh.2020.103004","url":null,"abstract":"The Sahelian regions have experienced a drought that has made them vulnerable to hydro-climatic conditions. Strategies have been developed to reduce this vulnerability. The governments of Senegal, Mauritania, Mali and Guinea have created the Organization for the development of the Senegal River (OMVS in french) with the aim of realizing large hydraulic installations. This resulted in the construction of the Diama and Manantali dams in the Senegal River Basin. The first aims to stop the saline intrusion, the second to regulate the flow of the river, to allow the irrigation of agricultural perimeters, and to produce electrical energy. The impoundment of the Diama dam has modified the hydraulic behavior of the estuary. The purpose of this study is to carry out the hydraulic modeling of the estuary of Senegal river downstream of the Diama Dam in transient mode by the HEC-RAS software. Two geometric models were constructed on the basis of a digital terrain model (DTM) using the Arc-GIS and HEC GeoRAS soft wares after processing the collected topographic data. The first geometric model, of which the areas of Senegal river downstream Diama Dam have been represented by cross-section, is one-dimensional. The second one is also one dimensional; in this model, the area of the Senegal River estuary downstream Diama Dam is introduced as water storage zones. The components of these models are the stream sections, lateral links, and storage areas. The flood hydrograph downstream Diama Dam is introduced as conditions at the upstream limits of the models while the tidal is introduced as a downstream condition. After the stability and calibration, the results given by HEC-RAS simulations are the variations of the water levels, the temporal variations of the flow rates for each section, the maximum flow velocities and the propagation times of the flood waves. The analysis and comparisons of these results strongly suggest using HEC-RAS issues as a decision-making tool helping to manage floods during times of crisis.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70315098","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}
Maurille P. S. Lanmandjèkpogni, F. P. Codo, B. Hountondji, B. Yao
Physiographic differences and conditions of use of water resources in anthropogenic basins explain the variability of risk to surface water. Based on the multi-criteria analysis of Saaty, the present work proposes an assessment of the vulnerability of surface water through a three-factor accessibility index: the slope, the subdivision rate and the drainage density of the basin. It is observed that the topographic (slope) and urbanistic (subdivision) conditions are the most important (weighting of 59%, 34%) in front of the hydrographic condition (drainage 6%) with an overall consistency of 2%. Thus, in the Okpara basin in the city of Parakou, the analysis of the vulnerability of surface waters by the accessibility index highlights two groups. The Ganre and Kokouro basins with about 30% of their areas in the low and moderate classes and the Wonka and Dama basins in the very strong class at more than 50% of their areas.
{"title":"Accessibility Index of Aquatic Environments as an Indicator of Surface Water Vulnerability in Urban Areas: Case of the Okpara Basin (Benin)","authors":"Maurille P. S. Lanmandjèkpogni, F. P. Codo, B. Hountondji, B. Yao","doi":"10.4236/ojmh.2019.94006","DOIUrl":"https://doi.org/10.4236/ojmh.2019.94006","url":null,"abstract":"Physiographic \u0000differences and conditions of use of water resources in anthropogenic basins \u0000explain the variability of risk to surface water. Based on the multi-criteria \u0000analysis of Saaty, the present work proposes an assessment of the vulnerability \u0000of surface water through a three-factor accessibility index: the slope, \u0000the subdivision rate and the drainage density of the basin. It is observed that \u0000the topographic (slope) and urbanistic (subdivision) conditions are the most \u0000important (weighting of 59%, 34%) in front of the hydrographic condition \u0000(drainage 6%) with an overall consistency of 2%. Thus, in the Okpara basin in \u0000the city of Parakou, the analysis of the vulnerability of surface waters by the \u0000accessibility index highlights two groups. The \u0000Ganre and Kokouro basins with about 30% of their areas in the low and moderate \u0000classes and the Wonka and Dama basins in the very strong class at more than 50% \u0000of their areas.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43589089","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}
Ethiopia has been booming with active construction of dams within the past few decades for different infrastructural needs, but has never experienced demolition or failure of dams in its history; hence little attention is being given to possible breach scenarios of dams and the resulting floodings. This paper makes analysis of the possible breach of kesem dam and the resulting flood inundation. In this study, the dam has been checked for both overtopping and piping failure modes using one dimensional river analysis model called HEC-RAS. Empirical equations were used to predict dam breach parameters of the two failure modes for use in this model. PMF inflow with a peak 9237.77 m3/s is used as an input to the reservoir to check if overtopping failure was possible. The spill way has proven to have adequate capacity for the flood due to the PMF. Therefore, breaching of the embankment was not possible. Piping failure was also simulated in HEC-RAS and the resulting breach due to piping failure, was analyzed and flood hydrograph was obtained at different cross sections along the river. These are flood hydrographs at 20 km, 40 km and 60 km at the downstream. The resulting flood plain was also mapped using HEC-GeoRas to show the extent of flooding.
{"title":"Dam Breach Analysis Using HEC-RAS and HEC-GeoRAS: The Case of Kesem Kebena Dam","authors":"Abimael Leoul, Nebiyou Kassahun","doi":"10.4236/OJMH.2019.94007","DOIUrl":"https://doi.org/10.4236/OJMH.2019.94007","url":null,"abstract":"Ethiopia has been booming with active construction of \u0000dams within the past few decades for different infrastructural needs, but has \u0000never experienced demolition or failure of dams in its history; hence little \u0000attention is being given to possible breach scenarios of dams and the resulting \u0000floodings. This paper makes analysis of the possible breach of kesem dam and \u0000the resulting flood inundation. In this study, the dam has been checked for \u0000both overtopping and piping failure modes using one dimensional river analysis \u0000model called HEC-RAS. Empirical equations were used to predict dam breach \u0000parameters of the two failure modes for use in this model. PMF inflow with a \u0000peak 9237.77 m3/s is used as an input to the reservoir to check if \u0000overtopping failure was possible. The spill way has proven to have adequate capacity \u0000for the flood due to the PMF. Therefore, breaching of the embankment was not \u0000possible. Piping failure was also simulated in HEC-RAS and the resulting breach \u0000due to piping failure, was analyzed and flood hydrograph was obtained at \u0000different cross sections along the river. These are flood hydrographs at 20 km, \u000040 km and 60 km at the downstream. The resulting flood plain was also mapped \u0000using HEC-GeoRas to show the extent of flooding.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47319643","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}
Despite all of the many discrepancies and contradictions in the estimate of the water balance in the Barada Awaj basin, all the research and reports, both local and international, indicate that the basin suffers from water depletion. The agricultural sector is the largest consumer of water, and the area of land irrigated by the basin has risen significantly. Rapid population growth as a result of natural increase and massive immigration to the basin, piratical well-digging without permits, the failure to increase the area of land irrigated by modern methods and a decrease in rainfall and the drought that has affected Syria in general and the Barada Awaj basin in particular, have led to a water shortage in the basin during the first decade of this century.
{"title":"Causes of Decreasing Water Balances in the Barada Awaj (Damascus) Drainage Basin until the Uprising in Syria","authors":"Firas Arraf","doi":"10.4236/ojmh.2019.94008","DOIUrl":"https://doi.org/10.4236/ojmh.2019.94008","url":null,"abstract":"Despite all of the many discrepancies and contradictions in the estimate of the water \u0000balance in the Barada Awaj basin, all the research and reports, both local and \u0000international, indicate that the basin suffers from water depletion. The \u0000agricultural sector is the largest consumer of water, and the area of land \u0000irrigated by the basin has risen significantly. Rapid population growth as a \u0000result of natural increase and massive immigration to the basin, piratical \u0000well-digging without permits, the failure to increase the area of land \u0000irrigated by modern methods and a decrease in rainfall and the drought that has \u0000affected Syria in general and the Barada Awaj basin in particular, have led to \u0000a water shortage in the basin during the first decade of this century.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46800478","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}
Water quality deterioration as a result of pollution comprised of several aspects, among others: nutrient input loads, fishery management, hydrological budget, toxicity, watershed deforestation, soil exposure, and exotic invaders. Thermal pollution is mostly considered as the impact of power or nuclear Station effluent or the effect of exceptional thermal abrupt shock. The long-term influence of global warming consideration is not extensively studied. The long-term (1969-2001) effect of climate change (warming and precipitation decline) on the Lake Kinneret ecosystem is presented. Water and air Temperature, Heat Capacity and Thermal conductivity of water combined with reduced precipitation accompanied by lake water level decline are analyzed. It was found that the temperature of surface water increased with WL decline and decreased in deep layers during high WL. Future management design is suggested.
{"title":"The Ecological Outcome of Climate Change in Lake Kinneret—Thermal Pollution","authors":"M. Gophen","doi":"10.4236/OJMH.2019.93005","DOIUrl":"https://doi.org/10.4236/OJMH.2019.93005","url":null,"abstract":"Water quality deterioration as a result of pollution \u0000comprised of several aspects, among others: nutrient input loads, fishery \u0000management, hydrological budget, toxicity, watershed deforestation, soil \u0000exposure, and exotic invaders. Thermal pollution is mostly considered as the \u0000impact of power or nuclear Station effluent or the effect of exceptional \u0000thermal abrupt shock. The long-term influence of global warming consideration \u0000is not extensively studied. The long-term (1969-2001) effect of climate change \u0000(warming and precipitation decline) on the Lake Kinneret ecosystem is \u0000presented. Water and air Temperature, Heat Capacity and Thermal conductivity of \u0000water combined with reduced precipitation accompanied by lake water level \u0000decline are analyzed. It was found that the temperature of surface water \u0000increased with WL decline and decreased in deep layers during high WL. Future \u0000management design is suggested.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42686633","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}
Climate change predictions for the Pacific Northwest region of the United States of America include increasing temperatures, intensification of winter precipitation, and a shift from mixed snow/rain to rain-dominant events, all of which may increase the risk of soil erosion and threaten agricultural and ecological productivity. Here we used the agricultural/environmental model SWAT with climate predictions from the Coupled Model Intercomparison Project 5 (CMIP5) “high CO2 emissions” scenario (RCP8.5) to study the impact of altered temperature and precipitation patterns on soil erosion and crop productivity in the Willamette River Basin of western Oregon. An ensemble of 10 climate models representing the full range in temperature and precipitation predictions of CIMP5 produced substantial increases in sediment yield, with differences between yearly averages for the final (2090-2099) and first (2010-2019) decades ranging from 3.9 to 15.2 MT·ha-1 among models. Sediment yield in the worst case model (CanESM2) corresponded to loss of 1.5 - 2.7 mm·soil·y-1, equivalent to potentially stripping productive topsoil from the landscape in under two centuries. Most climate models predicted only small increases in precipitation (an average of 5.8% by the end of the 21st century) combined with large increases in temperature (an average of 0.05°C·y-1). We found a strong correlation between predicted temperature increases and sediment yield, with a regression model combining both temperature and precipitation effects describing 79% of the total variation in annual sediment yield. A critical component of response to increased temperature was reduced snowfall during high precipitation events in the wintertime. SWAT characterized years with less than basin-wide averages of 20 mm of precipitation falling as snow as likely to experience severe sediment loss for multiple crops/land uses. Mid-elevation sub-basins that are projected to shift from rain-snow transition to rain-dominant appear particularly vulnerable to sediment loss. Analyses of predicted crop yields indicated declining productivity for many commonly grown grass seed and cereal crops, along with increasing productivity for certain other crops. Adaptation by agriculture and forestry to warmer, more erosive conditions may include changes in selection of crop kinds and in production management practices.
{"title":"Use of SWAT to Model Impact of Climate Change on Sediment Yield and Agricultural Productivity in Western Oregon, USA","authors":"G. Mueller-Warrant, C. Phillips, K. Trippe","doi":"10.4236/OJMH.2019.92004","DOIUrl":"https://doi.org/10.4236/OJMH.2019.92004","url":null,"abstract":"Climate change predictions for the Pacific Northwest region of the United States of America include increasing temperatures, intensification of winter precipitation, and a shift from mixed snow/rain to rain-dominant events, all of which may increase the risk of soil erosion and threaten agricultural and ecological productivity. Here we used the agricultural/environmental model SWAT with climate predictions from the Coupled Model Intercomparison Project 5 (CMIP5) “high CO2 emissions” scenario (RCP8.5) to study the impact of altered temperature and precipitation patterns on soil erosion and crop productivity in the Willamette River Basin of western Oregon. An ensemble of 10 climate models representing the full range in temperature and precipitation predictions of CIMP5 produced substantial increases in sediment yield, with differences between yearly averages for the final (2090-2099) and first (2010-2019) decades ranging from 3.9 to 15.2 MT·ha-1 among models. Sediment yield in the worst case model (CanESM2) corresponded to loss of 1.5 - 2.7 mm·soil·y-1, equivalent to potentially stripping productive topsoil from the landscape in under two centuries. Most climate models predicted only small increases in precipitation (an average of 5.8% by the end of the 21st century) combined with large increases in temperature (an average of 0.05°C·y-1). We found a strong correlation between predicted temperature increases and sediment yield, with a regression model combining both temperature and precipitation effects describing 79% of the total variation in annual sediment yield. A critical component of response to increased temperature was reduced snowfall during high precipitation events in the wintertime. SWAT characterized years with less than basin-wide averages of 20 mm of precipitation falling as snow as likely to experience severe sediment loss for multiple crops/land uses. Mid-elevation sub-basins that are projected to shift from rain-snow transition to rain-dominant appear particularly vulnerable to sediment loss. Analyses of predicted crop yields indicated declining productivity for many commonly grown grass seed and cereal crops, along with increasing productivity for certain other crops. Adaptation by agriculture and forestry to warmer, more erosive conditions may include changes in selection of crop kinds and in production management practices.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42547880","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}
S. Bansah, J. Quaye-Ballard, S. A. Andam-Akorful, Edward K. P. Bam, G. Anornu
The science that underpins our knowledge and understanding of Isotope-Based Hydrograph separation (IHS) has gained grounds, over the last few decades, in the identification of streamflow sources. However, challenges still exist in identifying appropriate tracers and the right combination of end-members for the IHS process. In a two-component IHS analysis, the application of the dual isotopes tracers, δ18O and (or) δ2H, is regarded as the simplest method. We undertook an IHS study within a nested system of eight Prairie watersheds located in South central Manitoba, Canada. The work evaluated about 17,000 results emanating from the application of a combination of two potential tracers (δ18O and δ2H) and eight each of potential “old” and “new” water end-members in a two-component IHS process. The outcome showed occurrences of many mathematically possible but hydrologically unacceptable IHS results. The observation was particularly predominant within relatively larger perennial sub-catchments of the watershed. It is also shown that inter-site sub-catchment isotopic end-member transferability is possible within watersheds of similar physio-hydrographic characteristics. We suggest that a careful evaluation of the physio-hydrographic characteristics of catchments be considered in IHS studies in addition to the recommended guidelines in the selection of tracers and end-members.
{"title":"End-Member Selection in Two-Component Isotope-Based Hydrograph Separation","authors":"S. Bansah, J. Quaye-Ballard, S. A. Andam-Akorful, Edward K. P. Bam, G. Anornu","doi":"10.4236/OJMH.2019.92003","DOIUrl":"https://doi.org/10.4236/OJMH.2019.92003","url":null,"abstract":"The science that underpins our knowledge and understanding of Isotope-Based Hydrograph separation (IHS) has gained grounds, over the last few decades, in the identification of streamflow sources. However, challenges still exist in identifying appropriate tracers and the right combination of end-members for the IHS process. In a two-component IHS analysis, the application of the dual isotopes tracers, δ18O and (or) δ2H, is regarded as the simplest method. We undertook an IHS study within a nested system of eight Prairie watersheds located in South central Manitoba, Canada. The work evaluated about 17,000 results emanating from the application of a combination of two potential tracers (δ18O and δ2H) and eight each of potential “old” and “new” water end-members in a two-component IHS process. The outcome showed occurrences of many mathematically possible but hydrologically unacceptable IHS results. The observation was particularly predominant within relatively larger perennial sub-catchments of the watershed. It is also shown that inter-site sub-catchment isotopic end-member transferability is possible within watersheds of similar physio-hydrographic characteristics. We suggest that a careful evaluation of the physio-hydrographic characteristics of catchments be considered in IHS studies in addition to the recommended guidelines in the selection of tracers and end-members.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41543188","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 Huron River consists of alternating bedrock reaches and alluvial reaches. Analysis of historical aerial photography from 1950-2015 reveals six major channel avulsion events in the 8-km study area. These avulsions occurred in the alluvial reaches but were strongly influenced by the properties of the upstream bedrock reach (“inherited characteristics”). The bedrock reaches aligned with the azimuth of joint sets in the underlying bedrock. One inherited characteristic in the alluvial reach downstream is that the avulsion channels diverged only slightly from the orientation of the upstream bedrock channel (range 2 ° - 38 °, mean and standard deviation 12.1 ° ± 13.7 °). A second inherited characteristic is that avulsion channels were initiated from short distances downstream after exiting the upstream bedrock channel reach (range 62 - 266 m, mean and standard deviation 143.7 ± 71.0 m), which is a fraction of the meander wavelength (1.2 km). Field evidence shows that some avulsion channel sites were re-occupied episodically. In addition, two properties were necessary for channel avulsions: 1) avulsion events were triggered by channel-forming hydrologic events (5-year recurrence interval flows), but not every channel-forming hydrologic event resulted in an avulsion, and 2) channel sinuosity (P) increased to 1.72 - 1.77 prior to an avulsion then decreased to 1.65 - 1.70 following an avulsion, suggesting that P ≥ 1.72 is the “critical sinuosity” or triggering value for avulsions on the Huron River. In summary, for this river consisting of alternating bedrock and alluvial reaches, the bedrock reaches impose certain parameters on downstream alluvial reaches (including sediment supply, channel direction and avulsion channel position downstream after exiting a bedrock reach) while adjustments in sinuosity and sediment storage occur in the alluvial reaches.
{"title":"Avulsion Dynamics in a River with Alternating Bedrock and Alluvial Reaches, Huron River, Northern Ohio (USA)","authors":"Mark J Potucek, J. Evans","doi":"10.4236/OJMH.2019.91002","DOIUrl":"https://doi.org/10.4236/OJMH.2019.91002","url":null,"abstract":"The Huron River consists of alternating bedrock reaches and alluvial reaches. Analysis of historical aerial photography from 1950-2015 reveals six major channel avulsion events in the 8-km study area. These avulsions occurred in the alluvial reaches but were strongly influenced by the properties of the upstream bedrock reach (“inherited characteristics”). The bedrock reaches aligned with the azimuth of joint sets in the underlying bedrock. One inherited characteristic in the alluvial reach downstream is that the avulsion channels diverged only slightly from the orientation of the upstream bedrock channel (range 2 ° - 38 °, mean and standard deviation 12.1 ° ± 13.7 °). A second inherited characteristic is that avulsion channels were initiated from short distances downstream after exiting the upstream bedrock channel reach (range 62 - 266 m, mean and standard deviation 143.7 ± 71.0 m), which is a fraction of the meander wavelength (1.2 km). Field evidence shows that some avulsion channel sites were re-occupied episodically. In addition, two properties were necessary for channel avulsions: 1) avulsion events were triggered by channel-forming hydrologic events (5-year recurrence interval flows), but not every channel-forming hydrologic event resulted in an avulsion, and 2) channel sinuosity (P) increased to 1.72 - 1.77 prior to an avulsion then decreased to 1.65 - 1.70 following an avulsion, suggesting that P ≥ 1.72 is the “critical sinuosity” or triggering value for avulsions on the Huron River. In summary, for this river consisting of alternating bedrock and alluvial reaches, the bedrock reaches impose certain parameters on downstream alluvial reaches (including sediment supply, channel direction and avulsion channel position downstream after exiting a bedrock reach) while adjustments in sinuosity and sediment storage occur in the alluvial reaches.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43067838","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 evaluated the probability of landslide susceptibilities through the applica-tion of the Transient Rainfall Infiltration and Grid-Based Region Slope-Stability model in Cau river basin (Vietnam) using the scenarios-based approach under the influence of the warming climate. The tested cases were developed based on various options including rainfall amount and distribution, soil depth determination, and land-cover conditions. Input data for extreme rain events included historical rainstorm in 2013, the Probable Maximum Precipitation (PMP) with the durations of 24 hours and 48 hours. The results illustrated the reduction of slope stability when the land cover changed from land-use data in 2007 (Ha12) to land-use data in 2015 (Ha22). When the whole region was assumed to be replaced by soil (Ha02), the factor of safety (Fs) decreased to lower magnitude when compared to Fs value regarding to changes in land cover condition (Ha12 & Ha22) and changes in soil-depth (Ha33). The model simulations demonstrated the agreement with the slope-failure hazard association with the destabilizing factor such as slope-cutting activities at historical landslide events. Under the same land-cover and soil depth condition, the average value of factor of safety regarding to the historical rainstorm in 2013 (Ha32) declined by 0.069 and 0.189 when compared to Fs of the 24-hour PMP with the storm distribution type 3 (1332) and Fs of the 48-hour PMP with the storm distribution type 3 (2332), respectively. The results reveal that in a warming climate, changes in extreme precipitation in terms of rain-total, rain-duration, and rain-distribution would result in the expansion of slope instability in the hilly region. This application is considered as a prevailing method for landslide susceptibility analysis and would provide important information for authorities in developing adequate land-management in the river basin.
{"title":"Evaluation of Landslide Susceptibility in Cau River Basin Using a Physical-Based Model under Impact of Climate Change","authors":"T. Le, Seiki Kawagoe","doi":"10.4236/OJMH.2019.91001","DOIUrl":"https://doi.org/10.4236/OJMH.2019.91001","url":null,"abstract":"This paper evaluated the probability of landslide susceptibilities through the applica-tion of the Transient Rainfall Infiltration and Grid-Based Region Slope-Stability model in Cau river basin (Vietnam) using the scenarios-based approach under the influence of the warming climate. The tested cases were developed based on various options including rainfall amount and distribution, soil depth determination, and land-cover conditions. Input data for extreme rain events included historical rainstorm in 2013, the Probable Maximum Precipitation (PMP) with the durations of 24 hours and 48 hours. The results illustrated the reduction of slope stability when the land cover changed from land-use data in 2007 (Ha12) to land-use data in 2015 (Ha22). When the whole region was assumed to be replaced by soil (Ha02), the factor of safety (Fs) decreased to lower magnitude when compared to Fs value regarding to changes in land cover condition (Ha12 & Ha22) and changes in soil-depth (Ha33). The model simulations demonstrated the agreement with the slope-failure hazard association with the destabilizing factor such as slope-cutting activities at historical landslide events. Under the same land-cover and soil depth condition, the average value of factor of safety regarding to the historical rainstorm in 2013 (Ha32) declined by 0.069 and 0.189 when compared to Fs of the 24-hour PMP with the storm distribution type 3 (1332) and Fs of the 48-hour PMP with the storm distribution type 3 (2332), respectively. The results reveal that in a warming climate, changes in extreme precipitation in terms of rain-total, rain-duration, and rain-distribution would result in the expansion of slope instability in the hilly region. This application is considered as a prevailing method for landslide susceptibility analysis and would provide important information for authorities in developing adequate land-management in the river basin.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70315475","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：