Books by Dr. Ahmed E El-Rayes
Papers by Dr. Ahmed E El-Rayes
International Journal on Environmental Sciences, 2015
Human activities contribute numerous hydrogeological threats including waterlogging, soil saliniz... more Human activities contribute numerous hydrogeological threats including waterlogging, soil salinization and water pollution in East Nile Delta region. Landsat Thematic Images were utilized to detect the environmental changes in the study area during the last three decades. Remote sensing and Geographic Information Systems data were integrated to monitor and measure surface areas of agricultural and urban developments. Risk assessment maps were constructed for waterlogging and soil salinization threats. The results cleared that both evaporation from logged and flood irrigation water surfaces cause up to 30% of water loss. The logged areas increased from 25km in 1984 to 180km in 2014 along the El-Tina plain which represents the most threated zone. The total changes of waterlogging cover at east Nile Delta varies between 930km in 1989, 685km in 1998 after the construction of El-Salam Canal and 1044km in 2014. The total estimated water loss by direct evaporation was up to 23.6Mm/year. Fo...
Geoenvironmental Disasters, 2023
Background The Southern Suez Canal Province (SSCP) has recently encountered hydro-environmental h... more Background The Southern Suez Canal Province (SSCP) has recently encountered hydro-environmental hazards such as water logging and soil salinization, both of which impede the efficient land use planning. Purpose This study aims to assess the hydro-environmental threats to SSCP and identify the key factors that contribute to their occurrence. Previous research has demonstrated that the Gulf of Suez Rifting-related tectonic movements have a significant impact on the entire SSCP region. The influence of tectonic setting on the development of hydroenvironmental dangers was not examined in almost any studies. Methods Remote sensing, GIS, hydrogeological, and geophysical techniques are used to identify and assess topographic, hydrogeological, and tectonic variables that affect hydro-environmental hazards in the SSCP. Results This study found that the distributions of water logging, saturated soil salinization, urban areas, and vegetation cover changed more dramatically between 1984 and 2015. The expansion of water logging area (+10.68 km 2 rating +0.35 km 2 /y), saturated saline soil (+24.40 km 2 rating +0.79 km 2 /y), and urbanized area (+58.43 km 2 rating +1.89 km 2 /y) is strongly associated to the expansion of vegetation cover (+188.13 km 2 at a rate of 6.07 km 2 /y). This could imply that growing agricultural expansion and urbanization are influencing the dominance of hydro-environmental hazards in SSCP. The distribution of water logging features identified on the land cover map corresponds closely to a buried horst structure dominating the middle part of the surveyed area. Conclusion The lowland water logging features of the SSCP provide support for the hypothesis that the buried horst structure that dominates the Miocene and pre-Miocene strata has an impact on the thickness and groundwater flow regime of the quaternary aquifer that lies above. The present study came to the conclusion that the shallow depth of groundwater, the vast expanse of newly cultivated lands, the impervious clay layer beneath the thin topsoil layer, and the low topography are the key factors influencing the development of water logging and soil salinization features in SSCP.
Journal of Mountain Science, 2023
The Safaga Region (SR) is part of the Red Sea mountain range in Egypt. Catastrophic flash floodin... more The Safaga Region (SR) is part of the Red Sea mountain range in Egypt. Catastrophic flash flooding is now an inescapable event, wreaking havoc and causing massive loss of life and property. The majority of the floodwater, however, has been wasted as runoff to the Red Sea, which, if used wisely, could meet a fraction of the water demands for a variety of applications in this area. The current work aims to use GIS techniques to integrate remote sensing data for evaluating, mitigating, and managing flash floods in SR. The data set comprised Tropical Rainfall Measuring Mission (TRMM) thematic rainfall data, 1:50,000 scale topographical map sheets, geological maps, the ASTER Digital Elevation Model (ASTER GDEM), Landsat 7 Enhanced Thematic Mapper" (ETM7+), and Landsat 8 Operational Land Imager. The flash flood risk model of SR is developed using ArcGIS-10.3 geoprocessing tools integrating all the causal factors thematic maps. The final flood risk model for the SR suggests that 57% of the total basins in the SR are at high risk of flooding. Almost 38% of all basins are at moderate flood risk. The remaining 5% of basins are less prone to flooding. Flood-prone zones were identified, suitable dam-building sites were located, and extremely probable areas for water recharge were recognized. On the basis of reliable scientific data, structural and non-structural mitigation strategies that might reduce the damage susceptibility, alleviate the sensitivity of the flash flood, and best utilize its water supply were recommended.
Environmental Systems Research, Jun 23, 2023
The impacts of Geo-hazard events are main obstacles to the use of land in numerous arid and semi-... more The impacts of Geo-hazard events are main obstacles to the use of land in numerous arid and semi-arid provinces of the World. Furthermore, the various activities of industrial communities, such as Egypt's 10th Ramadan Industrial Region (10th RIR), are the most dangerous examples of waste's impact on soil, surface water, and groundwater. The current study uses image processing and GIS tools to identify, delineate, monitor, and assess some of the environmental hazards caused by both human and natural activities in the 10th RIR. The findings revealed that there are rapid changes in land cover, which could be attributed to both anthropogenic and natural activities. Furthermore, the results revealed that waterlogging, salt-affected soils, water pollution, and flash floods were the most serious environmental threats to the 10th RIR. The obtained geo-hazard map showed that the 10th RIR has high flash flood hazards zones that are geospatially distributed in the southern parts of the Wadi Gafra basin and the western parts of 10th of Ramadan City. Furthermore, salinized soil zones are viewed as geospatially restricted zone in the eastern portion of 10th of Ramadan City and/or near the oxidation ponds. Additionally, vast areas of highly contaminated groundwater exist beneath industrial, urban, and oxidation pond zones. The current work provides decision-makers with numerous mitigation measures and recommendations required to minimize the impacts of geo-environmental hazards endangering the 10th RIR.
Journal of Coastal Conservation
The satellite data, include Landsat 7 Enhanced Thematic Mapper (ETM+), Landsat-8 (OLI), Shuttle R... more The satellite data, include Landsat 7 Enhanced Thematic Mapper (ETM+), Landsat-8 (OLI), Shuttle Radar Topography Mission (SRTM), were processed and interpreted for creating an integrated geospatial map of the geomorphic indices (GI) of Wadi Hagul Basin (WHB). The present study is considered new, useful, and valuable in northwest of Gulf of Suez region to evaluate active tectonics using SRTM resulting drainage network and GI. Where fairly slight studies on active tectonics recognized on GI were prepared in the investigated area. The GI includes; Ratio of valley floor width to valley height (Vf), Transverse topographic symmetry factor (T), Stream length-gradient index (SL), Drainage basin shape (Bs), hypsometric integral (Hi), geomorphological landform and watershed analysis. Also, GI were integrated and combined with the seismic and structural lineaments intensities maps to create an integrated single index map. The morphotectonic geo-spatial distribution hazards map reveals that the...
Arabian Journal of Geosciences
The current study used remote sensing, GIS, and seismic data to determine the geological and morp... more The current study used remote sensing, GIS, and seismic data to determine the geological and morphometric parameters of the Wadi Beda Basin area, which is located in the northwestern part of the Gulf of Suez Province. The geomorphic parameters related with the development of neotectonics are deduced using the Shuttle Radar Topography Mission (SRTM), DEM-derived catchments, and drainage networks of the research area. The most important geomorphic parameters applied to the current study area are valley floor width to height ratio (Vf), stream length gradient index (Sl), transverse topographic symmetry index (T), hypsometric curve and integral (HI), and drainage basin shape (Bs). Based on the obtained geomorphic parameter results, the Wadi El-Noqra and Wadi Umm Athala basins exhibit moderate tectonic activity and moderate symmetry and are considered to be at their mature stage. The main basins of Wadi Umm Elda and Wadi Beda are moderately symmetrical and reflect the youth stage. Howeve...
Journal of Coastal Conservation
The assessment of flash flood hazards in the coastal zone of Ras Ghareb City (RGC), Red Sea, Egyp... more The assessment of flash flood hazards in the coastal zone of Ras Ghareb City (RGC), Red Sea, Egypt, was accomplished through the use of GIS tools and the spatial multi-criteria approach. The presented work aims to assess, integrate, and generate potential flash flood hazard maps. The analytic hierarchy process was utilized to calculate weights of hazard and vulnerability of flash flood controlling factors and their parameters such as topographical, geological, and hydrological factors. In addition, the risk degree of each specific basin and its sub-basins is estimated by combining standardized parameter values. Despite its location in an arid region, the basin may receive a large amount of rainwater, which can cause flash floods at the basin's outlet. Recently, flash flooding took place in the coastal region of RGC in October 2016 and September 2020, resulting in the loss of many human lives and catastrophic effects on local infrastructure and surrounding environments. According...
The presented work is aimed at using GIS techniques to produce a potential flood hazard map based... more The presented work is aimed at using GIS techniques to produce a potential flood hazard map based on geomorphic parameters and to estimate the risk degree of individual subbasin by combining normalized values of the parameters. The study area-Dahab basin-is one of the most important basins in South Sinai, which drains into the Gulf of Aqaba, Egypt. It covers an area of about 2080 km 2. Although it is located in an arid region, the basin could receive a huge amount of rainwater during one of the rare storm events. The maximum recorded value reached up to 150 million m 3 /storm. Approximately 50% of the expected rainfall could turn into flash floods to the outlet of the basin, causing catastrophic effects on existing infrastructure and surrounding environments. Based on the Aster Digital Elevation Model, the drainage pattern of the Wadi's sub-basins were delineated and compared, with topographic map sheets of 1:50,000 scale as a reference. The sub-basins were extracted and morphometrically analysed to assess flash flood susceptibility. The morphometric parameters were measured by stream number and stream length. The parameters were computed using ESRI's ArcGIS 9.3, enriched by some VB code to compute stream numbers according to Strahler Theory. The case study results show that more than 35% of the sub-basins have high susceptibility of flooding and about 60% have medium susceptibility. Basins of high and moderate flood risk require detailed studies to implement actions to protect these areas against flood hazard.
Journal of Coastal Conservation, 2020
Groundwater (GW) is the primary source of water for local inhabitants in the Yemen Republic. The ... more Groundwater (GW) is the primary source of water for local inhabitants in the Yemen Republic. The Yemen Republic is dominated by an arid and semi-arid climate and suffers from a scarcity of natural resources and a soaring population growth rate. The IBB basin is one of the areas of main concern in Yemen, as the ascending local inhabitant's activities have led to an increase in the water demand throughout the IBB City (The major City of IBB basin area). The area is mainly covered by stratified volcanic rocks of Tertiary age. The current research aims to delineate, identify, integrate, assess and map the groundwater potentiality (GWP) zones in the Tertiary volcanic aquifer of the IBB basin, Yemen utilizing space-borne data and weighted overlay method in GIS tools. Thematic layers such as lithology, slope, plain curvature, structural lineaments density, geomorphology, land use/land cover, drainage density, and rainfall intensity were used as factors in the geo-database building of the GW potentiality map. To each class of the factor layers, a fixed score was assigned. The scores were ranked, and the weighted sum for all layers was calculated. Finally, a GW potentiality map of the IBB basin area was constructed by integrating the weighted thematic digital maps. The integrated model's results were classified into three main categories; low, moderate, and high GWP. The model validity was tested by considering the geospatial relationship between the resulted recharge productive zones and the distribution of the real-life productive wells and springs of IBB basin area. The integrated results successively delineate the GW potential zones in the IBB basin and raise awareness to methods useful for the management of GW resources and water recovery plans.
Environmental Earth Sciences, 2017
Land degradation and environmental impacts are major impediments to the utilization of land in ma... more Land degradation and environmental impacts are major impediments to the utilization of land in many arid and semiarid regions of the world and are a major issue in the Northwestern Sinai (NWS), Egypt. Monitoring and detecting of land-use/land-cover (LU/LC) changes and land degradation are very important for the planners, governments and the scientific communities, particularly where there are increasing pressures from human and natural activities on the adjacent environment. Waterlogged , saltaffected soils, coastal erosion and sand dunes encroachment are serious environmental hazards resulting in the wasteland and geoenvironmental risks. Presently, attempts have been made to analyze and determine the changes in LU/LC of NWS. The present work utilizes image processing and GIS techniques to determine most of the causes that result in intensive land degradations and recommends appropriate remedial measures within the NWS. Multi-temporal remote sensing data and ASTER GDEM were used to map the LU/ LC change areas. Many image processing techniques and statistical analysis were applied to draw numerous thematic and geospatial distribution maps for the degraded lands. The results showed that the rapid change in LC was attributed to human activities which led to heavy deteriorations of NWS environment. Also, the prevalence of natural risk corresponding to coastal erosion, water level rising and sand dunes encroachment increase the susceptibility of hazards to the NWS area. The current study provides decision makers and resources managers with appropriate remedial measures that are necessary to avoid severe future environmental difficulties within the NWS.
Wadi Ghweabae (3030 km2 area) is one of the largest hydrographic basins in the eastern desert of ... more Wadi Ghweabae (3030 km2 area) is one of the largest hydrographic basins in the eastern desert of Egypt. Many industrial projects are being started along the delta of this wadi. The basin receives a huge amount of rainwater which may reach as maximum as 149 million m3/storm with an annual mean value of 44 million m3/y. Up to 60 % of the maximum expected rainfall quantities could ran as flash floods to the outlet of the wadi causing a catastrophic effect on projects and surrounding environments. The present work is conducted to estimate the flood risks of this basin and to design a suitable management system to control its huge runoff quantities. The study aims also to use every possible source of water in the development strategies of the downstream industrial area. Three sub-basins, namely, Wadi El-Shonna, Wadi Ghweabae El-Soghier, and Wadi El Abyiad arerecognized as risky sub-basins. The resulted runoff due to the maximum rainfall storm event in these three sub-basins may reach as ...
Wadi Hagul (345 km2 area) is one of the largest hydrographic basins in the Eastern Desert of Egyp... more Wadi Hagul (345 km2 area) is one of the largest hydrographic basins in the Eastern Desert of Egypt. Many new major industrial projects are being started along the delta of this wadi. The basin area lies within the extremely arid belt of the Great Sahara. The rainfall over the study area is scarce, random and rarely exceeds 5mm as a monthly mean. However, the study area suddenly might receive large quantities of rainwater per one storm exceeding ten folds of the monthly mean quantities. The maximum amount of rainwater per one storm was recorded at Suez meteorological station as much as 49.6mm (October 1965) The equivalent amount of rainwater received by Wadi Hagul basin due to this maximum storm may reaches as maximum as 17 million m3/storm. Up to 64.7 % of the expected maximum rainfall quantities (about 11 million m3) could ran as flash floods through the outlet of the wadi, causing a catastrophic effect on the industrial projects and the surrounding environments. The present work i...
Drinking water resources in Wadi Feiran catchment area are available from three main types of aqu... more Drinking water resources in Wadi Feiran catchment area are available from three main types of aquifers, which are the fractured basement–cap aquifer, the Cretaceous-Miocene aquifer system and the Quaternary aquifer. Most of the discharged waters from these aquifers are characterized by low salt contents. They vary in composition between Ca-bicarbonate along the upstream basement terrain to Na(Mg)-chloride type along the downstream sedimentary reaches with a continuos lateral variation in each type mostly due to rock-water interactions /or biochemical processes. Although, most of the examined waters are of low salt contents, they are heavily polluted with microbiological and nutrients contaminants especially in / and around residential communities. These pollutants are more abundant in the shallow dug wells, around which reared animals breed and gardens are normally farmed. Algae are growing in most of these wells reflecting an environment enriched with nutrients and organic matters....
Journal of Coastal Conservation, 2015
Environmental land degradation is a major impediment to the utilization of land in many arid and ... more Environmental land degradation is a major impediment to the utilization of land in many arid and semi-arid regions of the World and is a major issue in the East Nile Delta (END), Egypt. Waterlogging and salt-affected soil problems have serious implications for irrigated areas leading to socio-economic and agricultural development problems. In the present study, timely and accurate detection of land degradation through remote sensing and hydrosalinity indicators, along with their characteristics and severity classification in a GIS environment, has been undertaken to provide, determine, assess and map reliable geo-information of environmental land degradation. This research deals with an assessment of hydrosalinity and environmental land degradation based on some new, but simple and practical, approaches for assessing salinity and spread of land degradation through digital image processing, geo-statistics and geochemistry. This analysis utilises Landsat 8, ASTER GDEM data, hydrochemical and statistical analyses using a GIS, together with other field collected data sets for the same date of May 2014. The hydrosalinity mapping and the statistical data analysis of TDS, major ions, groundwater grouping and hydrochemical facies and also water table maps between 1994 and 2014 reveals that the main sources of groundwater recharge and water bodies are mostly attributed to the continuous seepage from newly cultivated lands. The new flow regime is the main contributing factor to the rising water level, water salinity and waterlogging problems. Moreover, the spatial distribution of major ion content could be attributed to the leaching of aquifer materials along the flow path (Na, Ca, and Cl), the study area affected by agricultural pollution (Mg and SO4) and the leaching process which acts on the easily soluble evaporate-rich fluvio-marine sediments of a shallow aquifer (NO3 and PO4). The spatial distribution maps of the physico-chemical properties of soil such as EC, pH, SAR, Na, Cl, SO4 and Ca are compared with remote sensing salinity indices and then integrated to classify and map the salinity and salt-affected soil by using GIS tools. These indicate that increases in soil salinity levels pose a serious threat to sustainable agricultural developments that requires special attention to maintain an appropriate soil–water plant relationship by providing an adequate drainage system. The identification of land degradation mitigation measures requires thorough knowledge of the ground and surface water, human activities, and the salinity dynamics of the study area.
Arabian Journal of Geosciences, 2014
Geographic information system and remote sensing techniques are used to determine the spatial ass... more Geographic information system and remote sensing techniques are used to determine the spatial association between the hydrogeochemical and seismological evidences of wellknown geothermal fields in South Sinai. Manipulation, combination, overlay, integration and reattribution GIS functions have been used to explore the possible new occurrences of geothermal resources in South Sinai. Moreover, surface observations and lineament analysis of satellite images are used to delineate the active geothermal areas. The distribution of recent earthquake epicentres over South Sinai shows three main active trends (N 6°E, N 40°-75°E and N 50°-60°W) conformable with the long fault extensions extracted from ETM+7 and ASTER GDEM satellite images and comprise the well-known hot springs in South Sinai. It is found that wherever the N 6°E trend intersects both of N 50°-60°W or N 40°-75°E, the temperature of spring waters is remarkably increased. This feature could be attributed to the deep penetration of groundwater along the N 6°E fault trend (Gulf of Aqaba trend). The seismicity patterns of well-known and newly predicted geothermal sites show that the majority of earthquakes have focal depth range between 3 and 33 km (within the upper Earth crust) and have micro to moderate magnitude (0.5≥Mb≤4.5). In addition, the maximum focal depth of events reached up to 50 km at the Hammam Faroun area revealing the deep-seated thermal source. The main chemical type of the known thermal water of South Sinai is Cl-Na, indicating a long flow pathway of this water. The high calcium contents of thermal water of South Sinai are accompanied with remarkably low sulphates. This could be attributed to the microbial or thermal reduction of sulphates in contact with organic carbon which is confirmed by the emission of H 2 S gas observed at the known thermal field sites. As a result, thermal waters of the Hammam Faroun and Hammam Musa are undersaturated with respect to gypsum and anhydrite. The hydrochemistry of the newly predicted thermal sites exhibit similar pattern of the known thermal waters. Such observations are used as indicators to locate six predicted new occurrences of geothermal fields in South Sinai.
Earth Science Informatics, 2021
Rockfall is a natural hazard in mountainous areas not to be underestimated. Mass activities diffe... more Rockfall is a natural hazard in mountainous areas not to be underestimated. Mass activities differing in rock volume may cause considerable economic damage. Accomplishing qualitative appraisal of high-potential zones for rockfall is a first step towards implementing mitigation strategies. Nowadays, Geographical Information Systems (GIS) are the state-of-the-art tool for a fast and economic approach of identifying potential hazard zones rather than using conventional mapping with in-situ field data. Primarily, current research focuses on designing and implementing user-friendly tools delineating potential rockfall hazard zonation (RHZ). The constructed model examines triggering factors like slope, aspect, elevation, lithology, structural lineament, rainfall intensity, and seismic activity focal depth of a mountainous coastal region (Gulf of Aqaba, Egypt). The extracted geomorphological parameters were based on a high-resolution TanDEM-X Digital Elevation Model. The enhanced Landsat E...
Journal of Coastal Conservation, 2023
The satellite data, include Landsat 7 Enhanced Thematic Mapper (ETM+), Landsat-8 (OLI), Shuttle R... more The satellite data, include Landsat 7 Enhanced Thematic Mapper (ETM+), Landsat-8 (OLI), Shuttle Radar Topography Mission (SRTM), were processed and interpreted for creating an integrated geospatial map of the geomorphic indices (GI) of Wadi Hagul Basin (WHB). The present study is considered new, useful, and valuable in northwest of Gulf of Suez region to evaluate active tectonics using SRTM resulting drainage network and GI. Where fairly slight studies on active tectonics recognized on GI were prepared in the investigated area. The GI includes; Ratio of valley floor width to valley height (V f), Transverse topographic symmetry factor (T), Stream length-gradient index (S L), Drainage basin shape (B s), hypsometric integral (H i), geomorphological landform and watershed analysis. Also, GI were integrated and combined with the seismic and structural lineaments intensities maps to create an integrated single index map. The morphotectonic geo-spatial distribution hazards map reveals that the high risky area is 82.75% of the total area, the moderate-risk area is 16.51%, and the low risky morph-tectonic area is 0.81%. Based on this map, it is necessary for planners and decision makers to extremely study attractive applicable action concerning the recommended mitigation measurements from this study to avoid any serious future problems in WHB and its surroundings areas.
Environmental Systems Research, 2023
The impacts of Geo-hazard events are main obstacles to the use of land in numerous arid and semi-... more The impacts of Geo-hazard events are main obstacles to the use of land in numerous arid and semi-arid provinces of the World. Furthermore, the various activities of industrial communities, such as Egypt's 10th Ramadan Industrial Region (10th RIR), are the most dangerous examples of waste's impact on soil, surface water, and groundwater. The current study uses image processing and GIS tools to identify, delineate, monitor, and assess some of the environmental hazards caused by both human and natural activities in the 10th RIR. The findings revealed that there are rapid changes in land cover, which could be attributed to both anthropogenic and natural activities. Furthermore, the results revealed that waterlogging, salt-affected soils, water pollution, and flash floods were the most serious environmental threats to the 10th RIR. The obtained geo-hazard map showed that the 10th RIR has high flash flood hazards zones that are geospatially distributed in the southern parts of the Wadi Gafra basin and the western parts of 10th of Ramadan City. Furthermore, salinized soil zones are viewed as geospatially restricted zone in the eastern portion of 10th of Ramadan City and/or near the oxidation ponds. Additionally, vast areas of highly contaminated groundwater exist beneath industrial, urban, and oxidation pond zones. The current work provides decision-makers with numerous mitigation measures and recommendations required to minimize the impacts of geo-environmental hazards endangering the 10th RIR.
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Books by Dr. Ahmed E El-Rayes
Papers by Dr. Ahmed E El-Rayes