Globally,groundwater has globally emerged as a crucial freshwater source for domestic,irrigation,and industrial needs.The evaluation of groundwater quality in the Toshka region is imperative to ensure its suitability ...Globally,groundwater has globally emerged as a crucial freshwater source for domestic,irrigation,and industrial needs.The evaluation of groundwater quality in the Toshka region is imperative to ensure its suitability for the extensive agricultural and industrial activities underway in this promising,groundwater-dependent development area.This is particularly significant as Egypt increasingly relies on groundwater reserves to address freshwater deficits and to implement mega-development projects in barren lands.In this study,fifty-two samples were collected from the recently drilled wells tapping into the Nubian Sandstone Aquifer(NSA)in the Toshka region.Groundwater quality was assessed through hydrochemical analysis,Piper diagram,and various indicators such as Na%,SAR,RSC,KR,MH and PI.The hydrochemical analysis revealed improved groundwater quality characteristics,attributed to continuous recharge from Lake Nasser.The Piper diagram categorised most of the water samples as"secondary salinity"water type.Almost all wells proved suitable for irrigation with only two wells unsuitable based on MH values and six wells based on KR values.Considering Total Hardness(TH)values,all samples were classified as"Soft",indicating their suitability for domestic and industrial purposes.Water Quality Index(WQI)results concluded that all samples met WHO and FAO guidelines for drinking and irrigation,respectively.Spatial distribution maps,constructed using GIS,facilitate the interpretation of the results.Regular monitoring of quality parameters is essential to detect any deviation from permissible limits.展开更多
The quality of a water body is usually characterized by sets of physical, chemical, and biological parameters, which are mutually interrelated. Since August 1997, monthly records of 33 parameters, monitored at 102 loc...The quality of a water body is usually characterized by sets of physical, chemical, and biological parameters, which are mutually interrelated. Since August 1997, monthly records of 33 parameters, monitored at 102 locations on the Nile Delta drainage system, are stored in a National Database operated by the Drainage Research Institute (DRI). Correlation patterns may be found between water quantity and water quality parameters at the same location, or among water quality parameters within a monitoring location or among locations. Serial correlation is also detected in water quality variables. Through the investigation of the level of information redundancy, assessment and redesign of water quality monitoring network aim to improve the overall network efficiency and cost effectiveness. In this study, the potential of the Artificial Neural Network (ANN) on simulating interrelation between water quality parameters is examined. Several ANN inputs, structures and training possibilities are assessed and the best ANN model and modeling procedure is selected. The prediction capabilities of the ANN are compared with the linear regression models with autocorrelated residuals, usually used for this purpose. It is concluded that the ANN models are more accurate than the linear regression models having the same inputs and output.展开更多
Progressively anthropogenic intrusion and increasing water demand necessitate frequent water quality monitoring for sustainability management. Unlike laborious, time consuming field-based measurements, remote sensing-...Progressively anthropogenic intrusion and increasing water demand necessitate frequent water quality monitoring for sustainability management. Unlike laborious, time consuming field-based measurements, remote sensing-based water quality retrieval proved promising to overcome difficulties with temporal and spatial coverage. However, remotely estimated water quality parameters are mostly related to visibility characteristic and optically active property of water. This study presents results of an investigated approach to derive oxygen-related water quality parameter, namely Dissolved Oxygen (DO), in a shallow inland water body from satellite imagery. The approach deduces DO levels based on interrelated optical properties that dictate oxygen consumption and release in waters. Comparative analysis of multiple regression algorithms was carried out, using various combinations of parameters;namely, Turbidity, Total Suspended Solids (TSS), Chlorophyll-a, and Temperature. To cover the wide range of conditions that is experienced by Edku coastal lake, ground truth measurements covering the four seasons were used with corresponding satellite imageries. While results show successful statistically significant correlation in certain combinations considered, yet optimal results were concluded with Turbidity and natural logarithm of temperature. The algorithm model was developed with summer and fall data (R2 0.79), then validated with winter and spring data (R2 0.67). Retrieved DO concentrations highlighted the variability in pollution degree and zonation nature within that coastal lake, as related to boundary interactions and irregularity in flow dynamics within. The approach presented in this study encourages expanded applications with space-based earth observation products for exploring non-detectable water quality parameters that are interlinked with optically active properties in water.展开更多
The lack of water resources in Egypt’s Sinai Peninsula is a major constraint for further socioeconomic development, and flash floods in this region can damage roads and infrastructure. The Wadi Watir basin is the mai...The lack of water resources in Egypt’s Sinai Peninsula is a major constraint for further socioeconomic development, and flash floods in this region can damage roads and infrastructure. The Wadi Watir basin is the main water source for the groundwater aquifer, which supplies fresh water to Nuweiba city, where demands for groundwater are increasing. The objective of this research was to assess the hydrogeological suitability of installing Aquifer Storage and Recovery (ASR) systems in the Wadi Watir delta by using numerical groundwater models. The developed models were used to evaluate the effects of hydrogeological and operational parameters on the recovery efficiency of ASR systems at five potential locations in the study area. As the estimation of recovery efficiency depends on the salinity of recovered water, the recovered water salinity limit was assumed as 150% of the injected water salinity, where 150% refers to the point at which recovery has ended because the concentration of recovered water reached 150% of that of injected water. The most important output from the model runs was that the recovery efficiency of these ASR systems ranged from 25% to 54% with a longitudinal dispersivity of 10 m, volume of injected water of 12,000 m3, and storage period of 180 days. The main conclusions are as follows. 1) Using coupled numerical groundwater flow and solute transport models is an effective tool for predicting the effects of mixing between injected water and ambient groundwater in ASR systems. 2) The groundwater aquifer in the study area is not suitable as strategic area for ASR systems because the thickness of the water storage layer is relatively small and the distance to the sea is very close;consequently, it is recommended that artificial recharge systems be developed with existing technology to replenish the groundwater aquifer in the Wadi Watir delta.展开更多
Magnetic water treatment is considered as one of many techniques used worldwide that affects plant growth and development.This study examines whether there are beneficial effects of magnetic treatment of irrigation wa...Magnetic water treatment is considered as one of many techniques used worldwide that affects plant growth and development.This study examines whether there are beneficial effects of magnetic treatment of irrigation water on yield and water productivity as well as water saving.Three experiments were performed involving three crops(eggplant,faba beans and tomato)with different salinity tolerance thresholds ECw 0.7,1.1 and 1.7 dS/m,respectively.Two types of irrigation water were applied magnetically treated and non-magnetically treated.The experiments were carried out at Wadi EL Natroon station of Water Management Research Institute,El-Behira Governorate,Egypt during two sequentially winter seasons of 2015/2016 and 2016/2017 in a complete randomized design analysis with four replicates.There was a decrease of pH of the soil irrigated with magnetically treated water(MTW)compared with the non-MTW.The pH reached neutral values in some locations,especially the area cultivated with the faba beans(pH between 7.05 and 7.08).Results showed significant increases of water productivity for the MTW compared with non-MTW equal to 1.65,1.88 and 1.78 for eggplant,faba beans and tomato,respectively.It was also observed that the MTW affected the amounts of irrigation water added to different crops during its growing period.The percentages of water savings were 11%,13.5%and 14.2%for eggplant,faba beans and tomato,respectively.As a result the net return increased by 1.97,3.0 and 2.45 for the three crops,respectively.展开更多
Monitoring of variations in water for lakes and reservoirs is a requirement for meeting human needs and assessing ongoing climatic changes. However, regular gauging networks fail to provide the information needed for ...Monitoring of variations in water for lakes and reservoirs is a requirement for meeting human needs and assessing ongoing climatic changes. However, regular gauging networks fail to provide the information needed for water volume data. The aim of this study is to evaluate an approach to estimate water volume variation for the southern part of Lake Nasser in Egypt without in-situ gauge measurements and bathymetry maps. Combination of both Hydroweb satellite altimetry and Landsat 8 satellite imagery data was used. As compared to in-situ water levels, satellite altimetry provided accurate water levels variations for Lake Nasser;the RMSE was 0.28 m, with excellent agreement (R2 is 0.98). The lowest water level of altimetry database i.e. 174.57 m was used as a reference level for estimating water volumes variations for the study duration 8/2014-6/2015. All water altimetry levels were converted to differences of recorded water level above the lowest altimetry Level (ΔWL). Series of Landsat 8 imagery data were selected to extract surface areas corresponding to radar altimetry water levels dates. Areas-ΔWL relationship model was established as a polynomial function: A = f(ΔWL), and therefore, the relationship of the water volume above the lowest water level for the study time (ΔV) and ΔWL was obtained through the analytical integration of (Area-ΔWL) model. Another approach (Heron method) was also applied for estimating water volume variations. Validation of these two approaches showed that estimated water volume variations above reference water level using both methods i.e. integration and Heron agreed well with in-situ measurements of volume variation deduced from recent bathymetry map and in-situ water levels (R2 for both methods = 0.98). The RMSE for integration method is 323.89 MCM and for Heron method was 318.09 MCM, being approximately 13.2% of the mean volume variations above the lowest reference water level for mean surface area ≈658 km2. Another byproduct for these approaches was the modeling for a remote detecting water level. Once the F(L) relationship is set up for a given region, future Landsat images can be utilized to track water levels freely of radar altimetry. Finally it can be concluded that remote sensing resources (satellites radar altimeters and optical satellite images) that are openly accessible these days represent a great opportunity to remotely monitor reservoir water capacity and help in examining and observing hydrological and water driven procedures.展开更多
In this study,?the water flow and nitrate transport to a subsurface drain, using a simplified and detailed model, are simulated for the specific hydro-geological conditions of Elverdinge and Assenede, Belgium. Previou...In this study,?the water flow and nitrate transport to a subsurface drain, using a simplified and detailed model, are simulated for the specific hydro-geological conditions of Elverdinge and Assenede, Belgium. Previously, the DRAIN?MOD-N model proved to be able to simulate nitrate concentrations and drainage well for an?in-situleaching experiment, the?“Hooibeekhoeve”?in the community of Geel (north-eastern part of Belgium), conducted in 1992-1995. In this study, the calibrated model is used to simulate the nitrate leaching for the winter period 2000-2001 in Elverdinge and Assenede and is compared to a model with a simplified nitrate transport description. The comparative analysis between both model approaches reveals that the simplified model is able to predict sufficiently accurate the observed nitrate leaching. The detailed approach however has the advantage of giving?a more accurate estimate of the nitrogen mineralization, N deposition and denitrification, resulting in a more precise modeling of the nitrate leaching to surface waters and groundwater.展开更多
The system dynamics technique is used as a decision tool for engineering problems. It is one of the object oriented approaches that study and manage complex feedback systems. In this paper, the system dynamics techniq...The system dynamics technique is used as a decision tool for engineering problems. It is one of the object oriented approaches that study and manage complex feedback systems. In this paper, the system dynamics technique was used to simulate the performance of a drainage system under wheat crop in a clay soil. The model was calibrated and validated using observed experimental field data (drainage discharge and water table level) collected from Mashtul Pilot Area (MPA), Egypt. The results indicated that, the model is capable to predict hydrological parameters such as water table fluctuation, drainage discharge, upward flux, evapotranspiration, deep percolation, infiltration, runoff, soil moister content and unsaturated hydraulic conductivity on the basis of variation of soil moister content. The trends of the parameters found to be legible. Six statistical indexes were calculated to determine the agreement between the observed and simulated values of water table and drainage discharge. Results indicated that the system dynamics technique can be considered as a good decision tool to predict the subsurface drainage water precisely.展开更多
Egypt suffers from the impacts of climate change. Adaption plans should solve the shortage in water resources and increase the use of renewable energy. Detailed data on rainfall as non conventional water and detailed ...Egypt suffers from the impacts of climate change. Adaption plans should solve the shortage in water resources and increase the use of renewable energy. Detailed data on rainfall as non conventional water and detailed data on potential renewable energy are important. The added value of this research is to investigate the suitability of satellite data locally in North Sinai in Egypt. The Tropical Rainfall Measuring Mission (TRMM) satellites and available data from ground rain gauges are studied at North Sinai of Egypt. Local multiplication factors and correlation equations on a monthly basis were developed based on short term historical data. General equation based on short term data was developed to enhance TRMM data for the rainy season to minimize spatial and temporal errors. This equation would be very useful, especially in the ungauged areas in North Sinai to adjust TRMM rainfall data. TRMM data are spatially distributed, so it enhances the hydrology models for runoff estimation. This runoff could be used as non conventional water resource. The runoff was estimated in the RasSudr area in the 2010 storm to be 3.6 (m3/s). The hydropower of this runoff was estimated and ranged from 15,135 to 57,352 (kWh). The solar energy is studied from (NASA) satellite data. The monthly averaged solar energy was estimated to get possible generated power from the solar panel at locations of rainfall ground stations. The generated solar energy would supply self-sufficient energy for ground stations measuring instruments rather than batteries. The results show that a small solar panel project of 200 (m2) could safe electric network power by generating about 20,385 (kWh/year). The results of this study could help in enhancing adapting plans for climate change and runoff estimation model that needs grid data, especially in the area lacking ground data.展开更多
This study aimed to assess the impact of the Nile flood with special reference to turbidity on the food chain in Lake Nasser water as one of the largest man-made lakes in Africa before the flood (BF) and after the flo...This study aimed to assess the impact of the Nile flood with special reference to turbidity on the food chain in Lake Nasser water as one of the largest man-made lakes in Africa before the flood (BF) and after the flood (AF) seasons. To achieve that aim, subsurface water samples were collected from 11 sampling stations along the lake before and after the flood for analyzing the water turbidity, total suspended solids, and total phosphorus, as well as chlorophyll-<em>a</em> and zooplankton to represent the food chain in the lake. Results showed an increase in water turbidity after the flood than that before the flood. Total suspended solids concentration displayed a similar trend as water turbidity. Chlorophyll-<em>a</em> concentration increased in AF all over the lake except at the entrance of the lake, as compared to the BF season. Zooplankton count was represented by copepods, cladocerans, and rotifers with the dominance of copepods in AF and rotifers in BF. The density of zooplankton was higher in the AF than the BF season. The negative impact of flood turbidity had appeared on crustacean organisms.展开更多
The rapid expansion of both the global economy and the human population has led to a shortage of water resources suitable for direct human consumption.As a result,water remediation will inexorably become the primary f...The rapid expansion of both the global economy and the human population has led to a shortage of water resources suitable for direct human consumption.As a result,water remediation will inexorably become the primary focus on a global scale.Microalgae can be grown in various types of wastewaters(WW).They have a high potential to remove contaminants from the effluents of industries and urban areas.This review focuses on recent advances on WW remediation through microalgae cultivation.Attention has already been paid to microalgae-based wastewater treatment(WWT)due to its low energy requirements,the strong ability of microalgae to thrive under diverse environmental conditions,and the potential to transform WW nutrients into high-value compounds.It turned out that microalgae-based WWT is an economical and sustainable solution.Moreover,different types of toxins are removed by microalgae through biosorption,bioaccumulation,and biodegradation processes.Examples are toxins from agricultural runoffs and textile and pharmaceutical industrial effluents.Microalgae have the potential to mitigate carbon dioxide and make use of the micronutrients that are present in the effluents.This review paper highlights the application of microalgae in WW remediation and the remediation of diverse types of pollutants commonly present in WW through different mechanisms,simultaneous resource recovery,and efficient microalgae-based co-culturing systems along with bottlenecks and prospects.展开更多
Partial Rootzone Drying (PRD) is an irrigation technique which offers a means of modifying the growth and development of crops through relatively simple changes to the method of water delivery. The technique causes th...Partial Rootzone Drying (PRD) is an irrigation technique which offers a means of modifying the growth and development of crops through relatively simple changes to the method of water delivery. The technique causes the stimulation of physiological responses which are normally associated with water stress and this results in a significant reduction in water use through the production of chemical signals in drying roots. Partial drying of one half of the roots of plants grown with two root systems is rapidly translated into a reduction in transpiration and assimilation of all the crop leaves. The aim of this research is to examine and simulate the novel irrigation method (PRD), which would stimulate the endogenous stress response mechanisms of Conocarpus erectus trees in the pilot area of the Arabian Gulf University in Bahrain and wheat and maize crops in the Mashtul Pilot Area (MPA), Egypt using Saltmed model so that vigor is reduced and the efficiency of water use is enhanced. This is to be achieved by the manipulation of the hydration status of parts of a crop’s roots that could be used to control vegetative vigor without detrimental effects on canopy water relations. The PRD technique is researched for wheat as a winter crop and maize as a summer crop in Egypt. The technique causes the stimulation of physiological responses which are normally associated with water stress and this results in a significant reduction in water use through the production of chemical signals in drying roots. The results confirmed an increase in irrigation water use efficiency using PRD comparing with conventional flood irrigation. The research highly recommends applying the PRD method in the Gulf Cooperation Council (GCC) countries and in new reclaimed areas in Egypt to save water and improve crop quality.展开更多
Global Digital Elevation Models (DEMs) have been utilized in various geomatics activities worldwide. Recently, there exist several available DEMs vary significantly in terms of spatial resolution and release dates. Th...Global Digital Elevation Models (DEMs) have been utilized in various geomatics activities worldwide. Recently, there exist several available DEMs vary significantly in terms of spatial resolution and release dates. This paper examines the reliability of eight recent global DEMs, namely the EarthEnv-D90, SRTM 1, SRTM 3, ASTER, GMTED2010, GLOBE, GTOPO30, and AW3D30, in two study areas in Egypt and Saudi Arabia representing different topography patterns. Known ground control points with measured accurate coordinates and precise elevations have been utilized in evaluating the performance of those DEMs. It has been concluded that such a judgment procedure should not be carried based on a single statistical measure. First, five statistical measures, specifically the range, standard deviation, correlation, kurtosis, and skewness, have been evaluated separately for each DEM’s errors. Then, a new reliability index is introduced based on the weighted average concept. The accomplished results show that global DEMs perform differently in different topography patterns. It has been concluded that the EarthEnv-D90 and SRTM1 models attain high reliability indexes in the Nile delta region that represents a flat topography, while the GMTED2010 and EarthEnv-DEM90 models came in the first places for the second study area, Makkah, which represents mountainous topography.展开更多
This paper presents an analysis of four open-source Global Digital Elevation Models (GDEMs) and compares them on two topographic profiles (nearly flat, and hills regions) for mapping and geomatics applications. The ch...This paper presents an analysis of four open-source Global Digital Elevation Models (GDEMs) and compares them on two topographic profiles (nearly flat, and hills regions) for mapping and geomatics applications. The chief intention is to investigate if GDEMs-based heights, contour intervals, slopes, and topographic profiles are valid for all map scales of topographic mapping, which constitutes a major issue in mapping activities. Two case studies, the Nile delta in Egypt and Makkah city in Saudi Arabia, have been utilized to represent flat and moderate-topography patterns. The investigated GDEMs include the most-recent released models: ASTER v.3, ACE 2, SRTMGL1 v.3, and NASADEM_HGT v.1 released in 2019 and 2020 with spatial resolutions of 1 and 3 arc seconds. Available accurate Ground Control Points (GCP) consist of 540 stations in the Nile delta and 175 stations in Makkah. Based on the available datasets in two study areas, it has been found that the accuracy of investigated GDEMs over known checkpoints ranges from ±2.5 and ±5.1 meters in the Nile delta region, while it varies between ±5.1 and ±8.0 meters in the Makkah area. That indicates that the utilization of GDEMs in topographic mapping differs significantly between flat and hilly spatial regions. Therefore, it is recommended to avoid using GDEMs for developing topographic maps of scale 1:25,000 or larger in flat regions and map scale 1:50,000 or larger in hilly regions. Additionally, the accomplished results showed that all GDEM-based slopes do not match with the actual slopes from known GCP over cross section’s length up to 30 kilometers. Thus, it is concluded that GDEMs are not the appropriate heights’ source for topographic mapping at medium and large map scales, and could not be utilized for topographic profiling in precise engineering and geomatics applications.展开更多
With ever increasing demands on water resources, Egypt is facing increasing water needs, demanded by a rapidly growing population, by higher standards of living and by an agricultural policys. West Nile Delta represen...With ever increasing demands on water resources, Egypt is facing increasing water needs, demanded by a rapidly growing population, by higher standards of living and by an agricultural policys. West Nile Delta represents a new agricultural area where the reclaimed lands are irrigated with groundwater in addition to surface water. The evaluation of groundwater aquifers in West Nile Delta area requires information about the extension, depth and distribution and source of recharging these aquifers. In this work, an integrated study using geoelectric, geomagnetic, hydrogeologic and hydrochemistry investigations has been applied to evaluate groundwater aquifers and to delineate subsurface structures predominant in the basement rocks at El-Nubariya area, West Nile Delta, Egypt. Thirty-five Vertical Electrical Soundings (VES) have been applied to identify the subsurface geoelctric layers predominant in the study area. As well as a detailed land magnetic survey has been carried out along the study area using two automatic proton precession magnetometers with an accuracy of 1 nT. These surveys allowed us to establish the subsurface structures and their relation with the detected aquifers. The geoelectric results are illustrated along seven geoelectric profiles and correlated with the lithologic and hydrogeologic data of drilled wells. The third geoelectric layer represents the water saturated zone (aquifer) with thickness varies from 14 m to 58 m, increasing to east and southeast directions. The hydrchemisty anlysis shows that the salinity of the water aquifer ranges from 600 ppm in the southeast to 3900 ppm in the south. The major dominant dissolved salt is Nacl. In the east and southeast, the water type becomes more NaSO4 which refers to dissolution of gypsum in addition to fertilizers. The magnetic data have been analyzed using horizontal gradient and 3D magnetic modeling along the locations of geolectric profiles. The results indicate that the fault structures are trending in E-W, NW-SE and NE-SW directions. These faults confirm the results obtained from the well geolectric interpretation. These fault structures act as recharging paths from lower brackish to upper fresh water aquifers.展开更多
The present investigation demonstrates the synergistic action of using a sedimentation unit together with Cyperus papyrus(L.)wetland enriched with zeolite mineral in one-year round experiment for treating wastewater.T...The present investigation demonstrates the synergistic action of using a sedimentation unit together with Cyperus papyrus(L.)wetland enriched with zeolite mineral in one-year round experiment for treating wastewater.The system was designed to support a horizontal surface flow pattern and showed satisfactory removal efficiencies for both physicochemical and bacteriological contaminants within 3 days of residence time.The removal efficiencies ranged between 76.3%and 98.8%for total suspended solids,turbidity,iron,biological oxygen demand,and ammonia.The bacterial indicators(total and fecal coliforms,as well as fecal streptococci)and the potential pathogens(Escherichia coli,Staphylococcus aureus,and Pseudomonas aeruginosa)showed removal efficiencies ranged between 96.9%and 99.8%.We expect the system to offer a smart management for every component according to zero waste principle.The treated effluent was reused to irrigate the landscape of pilot area,and the excess sludge was recycled as fertilizer and soil conditioner.The zeolite mineral did not require regeneration for almost 36 weeks of operation,and enhanced the density of shoots(14.11%)and the height of shoots(15.88%).The harvested plant biomass could be a profitable resource for potent antibacterial and antioxidant bioactive compounds.This could certainly offset part of the operation and maintenance costs and optimize the system implementation feasibility.Although the experiment was designed under local conditions,its results could provide insights to upgrade and optimize the performance of other analogous large-scale constructed wetlands.展开更多
基金supported by the Ministry of Water Resources and Irrigation 2016(MWRI)which permitted access to the pumping wells,hydrogeological cross section near the study area and administered the sampling procedures。
文摘Globally,groundwater has globally emerged as a crucial freshwater source for domestic,irrigation,and industrial needs.The evaluation of groundwater quality in the Toshka region is imperative to ensure its suitability for the extensive agricultural and industrial activities underway in this promising,groundwater-dependent development area.This is particularly significant as Egypt increasingly relies on groundwater reserves to address freshwater deficits and to implement mega-development projects in barren lands.In this study,fifty-two samples were collected from the recently drilled wells tapping into the Nubian Sandstone Aquifer(NSA)in the Toshka region.Groundwater quality was assessed through hydrochemical analysis,Piper diagram,and various indicators such as Na%,SAR,RSC,KR,MH and PI.The hydrochemical analysis revealed improved groundwater quality characteristics,attributed to continuous recharge from Lake Nasser.The Piper diagram categorised most of the water samples as"secondary salinity"water type.Almost all wells proved suitable for irrigation with only two wells unsuitable based on MH values and six wells based on KR values.Considering Total Hardness(TH)values,all samples were classified as"Soft",indicating their suitability for domestic and industrial purposes.Water Quality Index(WQI)results concluded that all samples met WHO and FAO guidelines for drinking and irrigation,respectively.Spatial distribution maps,constructed using GIS,facilitate the interpretation of the results.Regular monitoring of quality parameters is essential to detect any deviation from permissible limits.
文摘The quality of a water body is usually characterized by sets of physical, chemical, and biological parameters, which are mutually interrelated. Since August 1997, monthly records of 33 parameters, monitored at 102 locations on the Nile Delta drainage system, are stored in a National Database operated by the Drainage Research Institute (DRI). Correlation patterns may be found between water quantity and water quality parameters at the same location, or among water quality parameters within a monitoring location or among locations. Serial correlation is also detected in water quality variables. Through the investigation of the level of information redundancy, assessment and redesign of water quality monitoring network aim to improve the overall network efficiency and cost effectiveness. In this study, the potential of the Artificial Neural Network (ANN) on simulating interrelation between water quality parameters is examined. Several ANN inputs, structures and training possibilities are assessed and the best ANN model and modeling procedure is selected. The prediction capabilities of the ANN are compared with the linear regression models with autocorrelated residuals, usually used for this purpose. It is concluded that the ANN models are more accurate than the linear regression models having the same inputs and output.
文摘Progressively anthropogenic intrusion and increasing water demand necessitate frequent water quality monitoring for sustainability management. Unlike laborious, time consuming field-based measurements, remote sensing-based water quality retrieval proved promising to overcome difficulties with temporal and spatial coverage. However, remotely estimated water quality parameters are mostly related to visibility characteristic and optically active property of water. This study presents results of an investigated approach to derive oxygen-related water quality parameter, namely Dissolved Oxygen (DO), in a shallow inland water body from satellite imagery. The approach deduces DO levels based on interrelated optical properties that dictate oxygen consumption and release in waters. Comparative analysis of multiple regression algorithms was carried out, using various combinations of parameters;namely, Turbidity, Total Suspended Solids (TSS), Chlorophyll-a, and Temperature. To cover the wide range of conditions that is experienced by Edku coastal lake, ground truth measurements covering the four seasons were used with corresponding satellite imageries. While results show successful statistically significant correlation in certain combinations considered, yet optimal results were concluded with Turbidity and natural logarithm of temperature. The algorithm model was developed with summer and fall data (R2 0.79), then validated with winter and spring data (R2 0.67). Retrieved DO concentrations highlighted the variability in pollution degree and zonation nature within that coastal lake, as related to boundary interactions and irregularity in flow dynamics within. The approach presented in this study encourages expanded applications with space-based earth observation products for exploring non-detectable water quality parameters that are interlinked with optically active properties in water.
文摘The lack of water resources in Egypt’s Sinai Peninsula is a major constraint for further socioeconomic development, and flash floods in this region can damage roads and infrastructure. The Wadi Watir basin is the main water source for the groundwater aquifer, which supplies fresh water to Nuweiba city, where demands for groundwater are increasing. The objective of this research was to assess the hydrogeological suitability of installing Aquifer Storage and Recovery (ASR) systems in the Wadi Watir delta by using numerical groundwater models. The developed models were used to evaluate the effects of hydrogeological and operational parameters on the recovery efficiency of ASR systems at five potential locations in the study area. As the estimation of recovery efficiency depends on the salinity of recovered water, the recovered water salinity limit was assumed as 150% of the injected water salinity, where 150% refers to the point at which recovery has ended because the concentration of recovered water reached 150% of that of injected water. The most important output from the model runs was that the recovery efficiency of these ASR systems ranged from 25% to 54% with a longitudinal dispersivity of 10 m, volume of injected water of 12,000 m3, and storage period of 180 days. The main conclusions are as follows. 1) Using coupled numerical groundwater flow and solute transport models is an effective tool for predicting the effects of mixing between injected water and ambient groundwater in ASR systems. 2) The groundwater aquifer in the study area is not suitable as strategic area for ASR systems because the thickness of the water storage layer is relatively small and the distance to the sea is very close;consequently, it is recommended that artificial recharge systems be developed with existing technology to replenish the groundwater aquifer in the Wadi Watir delta.
文摘Magnetic water treatment is considered as one of many techniques used worldwide that affects plant growth and development.This study examines whether there are beneficial effects of magnetic treatment of irrigation water on yield and water productivity as well as water saving.Three experiments were performed involving three crops(eggplant,faba beans and tomato)with different salinity tolerance thresholds ECw 0.7,1.1 and 1.7 dS/m,respectively.Two types of irrigation water were applied magnetically treated and non-magnetically treated.The experiments were carried out at Wadi EL Natroon station of Water Management Research Institute,El-Behira Governorate,Egypt during two sequentially winter seasons of 2015/2016 and 2016/2017 in a complete randomized design analysis with four replicates.There was a decrease of pH of the soil irrigated with magnetically treated water(MTW)compared with the non-MTW.The pH reached neutral values in some locations,especially the area cultivated with the faba beans(pH between 7.05 and 7.08).Results showed significant increases of water productivity for the MTW compared with non-MTW equal to 1.65,1.88 and 1.78 for eggplant,faba beans and tomato,respectively.It was also observed that the MTW affected the amounts of irrigation water added to different crops during its growing period.The percentages of water savings were 11%,13.5%and 14.2%for eggplant,faba beans and tomato,respectively.As a result the net return increased by 1.97,3.0 and 2.45 for the three crops,respectively.
文摘Monitoring of variations in water for lakes and reservoirs is a requirement for meeting human needs and assessing ongoing climatic changes. However, regular gauging networks fail to provide the information needed for water volume data. The aim of this study is to evaluate an approach to estimate water volume variation for the southern part of Lake Nasser in Egypt without in-situ gauge measurements and bathymetry maps. Combination of both Hydroweb satellite altimetry and Landsat 8 satellite imagery data was used. As compared to in-situ water levels, satellite altimetry provided accurate water levels variations for Lake Nasser;the RMSE was 0.28 m, with excellent agreement (R2 is 0.98). The lowest water level of altimetry database i.e. 174.57 m was used as a reference level for estimating water volumes variations for the study duration 8/2014-6/2015. All water altimetry levels were converted to differences of recorded water level above the lowest altimetry Level (ΔWL). Series of Landsat 8 imagery data were selected to extract surface areas corresponding to radar altimetry water levels dates. Areas-ΔWL relationship model was established as a polynomial function: A = f(ΔWL), and therefore, the relationship of the water volume above the lowest water level for the study time (ΔV) and ΔWL was obtained through the analytical integration of (Area-ΔWL) model. Another approach (Heron method) was also applied for estimating water volume variations. Validation of these two approaches showed that estimated water volume variations above reference water level using both methods i.e. integration and Heron agreed well with in-situ measurements of volume variation deduced from recent bathymetry map and in-situ water levels (R2 for both methods = 0.98). The RMSE for integration method is 323.89 MCM and for Heron method was 318.09 MCM, being approximately 13.2% of the mean volume variations above the lowest reference water level for mean surface area ≈658 km2. Another byproduct for these approaches was the modeling for a remote detecting water level. Once the F(L) relationship is set up for a given region, future Landsat images can be utilized to track water levels freely of radar altimetry. Finally it can be concluded that remote sensing resources (satellites radar altimeters and optical satellite images) that are openly accessible these days represent a great opportunity to remotely monitor reservoir water capacity and help in examining and observing hydrological and water driven procedures.
文摘In this study,?the water flow and nitrate transport to a subsurface drain, using a simplified and detailed model, are simulated for the specific hydro-geological conditions of Elverdinge and Assenede, Belgium. Previously, the DRAIN?MOD-N model proved to be able to simulate nitrate concentrations and drainage well for an?in-situleaching experiment, the?“Hooibeekhoeve”?in the community of Geel (north-eastern part of Belgium), conducted in 1992-1995. In this study, the calibrated model is used to simulate the nitrate leaching for the winter period 2000-2001 in Elverdinge and Assenede and is compared to a model with a simplified nitrate transport description. The comparative analysis between both model approaches reveals that the simplified model is able to predict sufficiently accurate the observed nitrate leaching. The detailed approach however has the advantage of giving?a more accurate estimate of the nitrogen mineralization, N deposition and denitrification, resulting in a more precise modeling of the nitrate leaching to surface waters and groundwater.
文摘The system dynamics technique is used as a decision tool for engineering problems. It is one of the object oriented approaches that study and manage complex feedback systems. In this paper, the system dynamics technique was used to simulate the performance of a drainage system under wheat crop in a clay soil. The model was calibrated and validated using observed experimental field data (drainage discharge and water table level) collected from Mashtul Pilot Area (MPA), Egypt. The results indicated that, the model is capable to predict hydrological parameters such as water table fluctuation, drainage discharge, upward flux, evapotranspiration, deep percolation, infiltration, runoff, soil moister content and unsaturated hydraulic conductivity on the basis of variation of soil moister content. The trends of the parameters found to be legible. Six statistical indexes were calculated to determine the agreement between the observed and simulated values of water table and drainage discharge. Results indicated that the system dynamics technique can be considered as a good decision tool to predict the subsurface drainage water precisely.
文摘Egypt suffers from the impacts of climate change. Adaption plans should solve the shortage in water resources and increase the use of renewable energy. Detailed data on rainfall as non conventional water and detailed data on potential renewable energy are important. The added value of this research is to investigate the suitability of satellite data locally in North Sinai in Egypt. The Tropical Rainfall Measuring Mission (TRMM) satellites and available data from ground rain gauges are studied at North Sinai of Egypt. Local multiplication factors and correlation equations on a monthly basis were developed based on short term historical data. General equation based on short term data was developed to enhance TRMM data for the rainy season to minimize spatial and temporal errors. This equation would be very useful, especially in the ungauged areas in North Sinai to adjust TRMM rainfall data. TRMM data are spatially distributed, so it enhances the hydrology models for runoff estimation. This runoff could be used as non conventional water resource. The runoff was estimated in the RasSudr area in the 2010 storm to be 3.6 (m3/s). The hydropower of this runoff was estimated and ranged from 15,135 to 57,352 (kWh). The solar energy is studied from (NASA) satellite data. The monthly averaged solar energy was estimated to get possible generated power from the solar panel at locations of rainfall ground stations. The generated solar energy would supply self-sufficient energy for ground stations measuring instruments rather than batteries. The results show that a small solar panel project of 200 (m2) could safe electric network power by generating about 20,385 (kWh/year). The results of this study could help in enhancing adapting plans for climate change and runoff estimation model that needs grid data, especially in the area lacking ground data.
文摘This study aimed to assess the impact of the Nile flood with special reference to turbidity on the food chain in Lake Nasser water as one of the largest man-made lakes in Africa before the flood (BF) and after the flood (AF) seasons. To achieve that aim, subsurface water samples were collected from 11 sampling stations along the lake before and after the flood for analyzing the water turbidity, total suspended solids, and total phosphorus, as well as chlorophyll-<em>a</em> and zooplankton to represent the food chain in the lake. Results showed an increase in water turbidity after the flood than that before the flood. Total suspended solids concentration displayed a similar trend as water turbidity. Chlorophyll-<em>a</em> concentration increased in AF all over the lake except at the entrance of the lake, as compared to the BF season. Zooplankton count was represented by copepods, cladocerans, and rotifers with the dominance of copepods in AF and rotifers in BF. The density of zooplankton was higher in the AF than the BF season. The negative impact of flood turbidity had appeared on crustacean organisms.
基金supported by the National Natural Science Foundation of China(31772529)the National Key R&D Program of China(2018YFE0107100)the Priority of Academic Program Development of Jiangsu Higher Education Institutions(PAPD 4013000011).
文摘The rapid expansion of both the global economy and the human population has led to a shortage of water resources suitable for direct human consumption.As a result,water remediation will inexorably become the primary focus on a global scale.Microalgae can be grown in various types of wastewaters(WW).They have a high potential to remove contaminants from the effluents of industries and urban areas.This review focuses on recent advances on WW remediation through microalgae cultivation.Attention has already been paid to microalgae-based wastewater treatment(WWT)due to its low energy requirements,the strong ability of microalgae to thrive under diverse environmental conditions,and the potential to transform WW nutrients into high-value compounds.It turned out that microalgae-based WWT is an economical and sustainable solution.Moreover,different types of toxins are removed by microalgae through biosorption,bioaccumulation,and biodegradation processes.Examples are toxins from agricultural runoffs and textile and pharmaceutical industrial effluents.Microalgae have the potential to mitigate carbon dioxide and make use of the micronutrients that are present in the effluents.This review paper highlights the application of microalgae in WW remediation and the remediation of diverse types of pollutants commonly present in WW through different mechanisms,simultaneous resource recovery,and efficient microalgae-based co-culturing systems along with bottlenecks and prospects.
文摘Partial Rootzone Drying (PRD) is an irrigation technique which offers a means of modifying the growth and development of crops through relatively simple changes to the method of water delivery. The technique causes the stimulation of physiological responses which are normally associated with water stress and this results in a significant reduction in water use through the production of chemical signals in drying roots. Partial drying of one half of the roots of plants grown with two root systems is rapidly translated into a reduction in transpiration and assimilation of all the crop leaves. The aim of this research is to examine and simulate the novel irrigation method (PRD), which would stimulate the endogenous stress response mechanisms of Conocarpus erectus trees in the pilot area of the Arabian Gulf University in Bahrain and wheat and maize crops in the Mashtul Pilot Area (MPA), Egypt using Saltmed model so that vigor is reduced and the efficiency of water use is enhanced. This is to be achieved by the manipulation of the hydration status of parts of a crop’s roots that could be used to control vegetative vigor without detrimental effects on canopy water relations. The PRD technique is researched for wheat as a winter crop and maize as a summer crop in Egypt. The technique causes the stimulation of physiological responses which are normally associated with water stress and this results in a significant reduction in water use through the production of chemical signals in drying roots. The results confirmed an increase in irrigation water use efficiency using PRD comparing with conventional flood irrigation. The research highly recommends applying the PRD method in the Gulf Cooperation Council (GCC) countries and in new reclaimed areas in Egypt to save water and improve crop quality.
文摘Global Digital Elevation Models (DEMs) have been utilized in various geomatics activities worldwide. Recently, there exist several available DEMs vary significantly in terms of spatial resolution and release dates. This paper examines the reliability of eight recent global DEMs, namely the EarthEnv-D90, SRTM 1, SRTM 3, ASTER, GMTED2010, GLOBE, GTOPO30, and AW3D30, in two study areas in Egypt and Saudi Arabia representing different topography patterns. Known ground control points with measured accurate coordinates and precise elevations have been utilized in evaluating the performance of those DEMs. It has been concluded that such a judgment procedure should not be carried based on a single statistical measure. First, five statistical measures, specifically the range, standard deviation, correlation, kurtosis, and skewness, have been evaluated separately for each DEM’s errors. Then, a new reliability index is introduced based on the weighted average concept. The accomplished results show that global DEMs perform differently in different topography patterns. It has been concluded that the EarthEnv-D90 and SRTM1 models attain high reliability indexes in the Nile delta region that represents a flat topography, while the GMTED2010 and EarthEnv-DEM90 models came in the first places for the second study area, Makkah, which represents mountainous topography.
文摘This paper presents an analysis of four open-source Global Digital Elevation Models (GDEMs) and compares them on two topographic profiles (nearly flat, and hills regions) for mapping and geomatics applications. The chief intention is to investigate if GDEMs-based heights, contour intervals, slopes, and topographic profiles are valid for all map scales of topographic mapping, which constitutes a major issue in mapping activities. Two case studies, the Nile delta in Egypt and Makkah city in Saudi Arabia, have been utilized to represent flat and moderate-topography patterns. The investigated GDEMs include the most-recent released models: ASTER v.3, ACE 2, SRTMGL1 v.3, and NASADEM_HGT v.1 released in 2019 and 2020 with spatial resolutions of 1 and 3 arc seconds. Available accurate Ground Control Points (GCP) consist of 540 stations in the Nile delta and 175 stations in Makkah. Based on the available datasets in two study areas, it has been found that the accuracy of investigated GDEMs over known checkpoints ranges from ±2.5 and ±5.1 meters in the Nile delta region, while it varies between ±5.1 and ±8.0 meters in the Makkah area. That indicates that the utilization of GDEMs in topographic mapping differs significantly between flat and hilly spatial regions. Therefore, it is recommended to avoid using GDEMs for developing topographic maps of scale 1:25,000 or larger in flat regions and map scale 1:50,000 or larger in hilly regions. Additionally, the accomplished results showed that all GDEM-based slopes do not match with the actual slopes from known GCP over cross section’s length up to 30 kilometers. Thus, it is concluded that GDEMs are not the appropriate heights’ source for topographic mapping at medium and large map scales, and could not be utilized for topographic profiling in precise engineering and geomatics applications.
文摘With ever increasing demands on water resources, Egypt is facing increasing water needs, demanded by a rapidly growing population, by higher standards of living and by an agricultural policys. West Nile Delta represents a new agricultural area where the reclaimed lands are irrigated with groundwater in addition to surface water. The evaluation of groundwater aquifers in West Nile Delta area requires information about the extension, depth and distribution and source of recharging these aquifers. In this work, an integrated study using geoelectric, geomagnetic, hydrogeologic and hydrochemistry investigations has been applied to evaluate groundwater aquifers and to delineate subsurface structures predominant in the basement rocks at El-Nubariya area, West Nile Delta, Egypt. Thirty-five Vertical Electrical Soundings (VES) have been applied to identify the subsurface geoelctric layers predominant in the study area. As well as a detailed land magnetic survey has been carried out along the study area using two automatic proton precession magnetometers with an accuracy of 1 nT. These surveys allowed us to establish the subsurface structures and their relation with the detected aquifers. The geoelectric results are illustrated along seven geoelectric profiles and correlated with the lithologic and hydrogeologic data of drilled wells. The third geoelectric layer represents the water saturated zone (aquifer) with thickness varies from 14 m to 58 m, increasing to east and southeast directions. The hydrchemisty anlysis shows that the salinity of the water aquifer ranges from 600 ppm in the southeast to 3900 ppm in the south. The major dominant dissolved salt is Nacl. In the east and southeast, the water type becomes more NaSO4 which refers to dissolution of gypsum in addition to fertilizers. The magnetic data have been analyzed using horizontal gradient and 3D magnetic modeling along the locations of geolectric profiles. The results indicate that the fault structures are trending in E-W, NW-SE and NE-SW directions. These faults confirm the results obtained from the well geolectric interpretation. These fault structures act as recharging paths from lower brackish to upper fresh water aquifers.
基金The authors wish to express their gratitude to the Microbiology Dep.,Central Laboratory for Environmental Quality Monitoring(CLEQM),National Water Research Center(NWRC)in Egypt for supporting this work.The authors would like also to thank Mr.Kyle Bowman,Head Bioelectrochemical Engineer at Wase-tech,London,UK for his language editing revision of the manuscript.
文摘The present investigation demonstrates the synergistic action of using a sedimentation unit together with Cyperus papyrus(L.)wetland enriched with zeolite mineral in one-year round experiment for treating wastewater.The system was designed to support a horizontal surface flow pattern and showed satisfactory removal efficiencies for both physicochemical and bacteriological contaminants within 3 days of residence time.The removal efficiencies ranged between 76.3%and 98.8%for total suspended solids,turbidity,iron,biological oxygen demand,and ammonia.The bacterial indicators(total and fecal coliforms,as well as fecal streptococci)and the potential pathogens(Escherichia coli,Staphylococcus aureus,and Pseudomonas aeruginosa)showed removal efficiencies ranged between 96.9%and 99.8%.We expect the system to offer a smart management for every component according to zero waste principle.The treated effluent was reused to irrigate the landscape of pilot area,and the excess sludge was recycled as fertilizer and soil conditioner.The zeolite mineral did not require regeneration for almost 36 weeks of operation,and enhanced the density of shoots(14.11%)and the height of shoots(15.88%).The harvested plant biomass could be a profitable resource for potent antibacterial and antioxidant bioactive compounds.This could certainly offset part of the operation and maintenance costs and optimize the system implementation feasibility.Although the experiment was designed under local conditions,its results could provide insights to upgrade and optimize the performance of other analogous large-scale constructed wetlands.