Wadi El Research Articles

Osmophilic/osmotolerant and halophilic/halotolerant fungi from mud, salt crusts, and air collected from Wadi El- Natrun lakes

Osmophilic/osmotolerant and halophilic/halotolerant fungi from mud, salt crusts, and air collected from Wadi El- Natrun lakes

Messinian Lago-Mare ostracods from Tunisia

Micropalaeontological analyses were performed on two stratigraphical sections sampled in upper Messinian deposits outcropping in eastern Tunisia, allowing us to identify some sedimentary levels with high concentrations of fresh or brackish water ostracods, which can be referred to the Lago-Mare fauna. Some of these species can be considered Paratethysian, or rather as species that spread in the Mediterranean area starting from the Paratethys areas, while others show Paratethysian affinity. The Lago-Mare fauna is little known in the south Mediterranean regions and the present article provides new data on its geographic distribution. Of the two sections sampled, the first one, the Wadi El Kebir section, is located in the south eastern part of the Cape Bon Peninsula and shows horizons dominated by Cyprideis agrigentina and Cyprideis ex C. torosa group; the second one, the Salakta section, is located in the Sahel region and shows a level with a very rich Lago-Mare ostracod fauna consisting essentially of Amnicythere propinqua, Mediocytherideis punctata, and Ilyocypris gibba.

Assessment and Spatial Analysis of Sensitivity to Desertification in Wadi El Natrun, Northwestern Egypt using MEDLAUS model

Land degradation is a global environmental issue, given the various negative impact on socio-economic and ecological implications. It leads to reduced production capacity in addition to soil erosion, physical /chemical /biological /economic land deterioration, and long-term loss (or degradation) of vegetation. When a severe deterioration in drought areas called the process of desertification i.e. arid, dry sub-humid and semi-arid areas. Desertification processes reduces the productivity of the soil and as a result effect on food stocks. The main objective of this study is integrating remote sensing data and a geographic information system (GIS) to evaluate the environmental sensitivity for desertification in Wadi El Natrun, Egypt based on the Mediterranean Desertification and Land Use (MEDALUS) approach. The collected soil data; from description of represented soil profiles and analysis of soil samples, in addition to climate, plant cover, and management data were considered for assessing the sensitivity of desertification. The obtained results showed that 10.4 % of Wadi El Natrun area is considered severe sensitivity to desertification as a result of alkalinity and salinity, while the moderately sensitive area occupies approximately 10.93 % of the study area. The low sensitive one exhibits 76.3 %. This area is described by high soil quality because of the study area is one of the new development areas which were not affected by the factors of desertification. It can be concluded that the desert extension of El-Beheira Governorate (i.e. Wadi El Rayan) is one of the areas that possess valuable land resources which should be considered for future land reclamation projects. Similar international studies are recommended to be achieved with the use of multi-criteria GIS modeling (i.e. MEDALUS) which considered all relevant factors in the form of thematic layers for easier implementation and assessments. Present study represents one of the initial attempts to use the MEDALUS model for desertification assessment in the desert extension of El-Beheira Governorate.

Delineation of groundwater recharge zones in the Mitidja plain, north Algeria, using multi-criteria analysis

Abstract This work aims to identify the potential groundwater recharge zones in the Mitidja plain (north Algeria) using the multi-criteria approach. The analysis was based on the use of a geographical information system (GIS) and remote sensing to establish eight thematic maps, weighted, categorized and inserted, that allowed us to establish the potential zones’ map for groundwater recharge. Three potential groundwater recharge classes were defined corresponding, respectively, to low (26%), moderate (47%) and high (27%). The best groundwater potential zones are situated in the piedmont of the Blidean Atlas (the south of the study area), precisely, upstream near to wadis (wadi El Harrach, wadi Djemaa, wadi Mazafran) and the western aquifer limit, where the hydrogeological units are formed by the alluvium formation which is characterized by high hydraulic conductivity, high water flow, low slope, low drainage, low quantity transported sediments and good water quality. The obtained results, in this work, describe the groundwater recharge potential areas and supply information for a suitable mapping and the management of aquifer resources in the study area.

Composition and changes in the spontaneous flora of the Wadi El Rayan Ramsar site, Fayoum, Egypt, in the last 20 years

Abstract Wadi El Rayan is located in Egypt in the Sahara ecoregion the Palearctic ecozone (the world’s largest hot desert). The total area of Wadi El Rayan is 1759km2. The aim of this work was to study the ecosystems, compare species composition, species richness and species diversity of the study sites in the Wadi El Rayan protected area and the distributions of plants in the different landform. The field observations found that there is a low diversity and number of plant species around the lakes, in particular a decline in vegetation cover in accordance with a dramatic decrease in the water level in the lakes compared to earlier studies. The reduction of water levels due to decreased water supply is considered the main threat facing ecosystems and biodiversity in the lake area which requires a continuous survey of flora and measures to be implemented to conserve the natural vegetation in the area. Based on investigations of the spontaneous flora of Wadi El Rayan in 2018, 18 taxa of vascular plants were recorded. This inventory was compared with published records of investigations made in 1998, 2002 and 2014. A total of 18 vascular plant species belonging to 14 families were recorded in the wetland and desert ecosystems around the lakes of Wadi El Rayan. The vegetation mainly consists of sparsely distributed xerophytic and halophytic plants except in the wetland ecosystem around the lakes where it is characterized by some hydrophytic and halophytic plants. The family with the highest number of species was Poaceae followed by Zygophyllaceae. The results showed that a higher number of species was recorded from the Lower Lake (13 species) than the Upper Lake (10 species) and (5 species) for the connecting channel. The most frequently recorded species were Phragmites australis, Tamarix nilotica, Juncus rigidus and Alhagi graecorum: the first two species were the most successful species as they grow in a variety of ecosystems and habitats.

Factors controlling in the concentration of gold and uranium in the Lower Carboniferous marl at Wadi El Kharig area, Southwestern Sinai, Egypt

The Lower Carboniferous middle member of Um Bogma Formation at Wadi El Kharig composed mainly of marl and interbedded dolostone with pockets of gibbsite and marly gibbsite. The organic carbon (related to the presence of organic matter) reaches 2.31%, 6.39%, and 1.36% in the marly gibbsite, black gibbsite, and marl, respectively. The black gibbsite and marly gibbsite have high concentrations of some metals such as Zn, Cu, Ba, and Ni than that in the marl. New detection of high radioactive anomalies was recorded at Wadi El Kharig in the marly gibbsite, black gibbsite, and marl of the middle member of Um Bogma Formation with an average of U-content reaches 342, 726.3, and 229 ppm, respectively. Metatorbernite, carnotite, and autunite are the main secondary uranium minerals recorded in the radioactive facies. Also, new occurrences of gold were recorded at Wadi El Kharig in the marl (1.2 ppm) and its interbedded dolostone (1.4 ppm) of the middle member of Um Bogma Formation. Carbonaceous material and/or organic matter in addition to the presence of iron oxides are playing important roles in the concentration of Au and U and some metals in the studied facies.

Integrating of remote sensing, GIS and geophysical data for recharge potentiality evaluation in Wadi El Tarfa, eastern desert, Egypt

In Egypt, water resources management is considered a major socio-economic issue and a central component for future development. With the increasing rate of population growth, urbanization and agricultural expansion, groundwater resources are gaining more demand and attention. Wadi El Tarfa area is one of the semi-arid areas located in the Eastern Desert of Egypt, composed of Cretaceous and Eocene limestone and Quaternary sediments. This study focused on delineation, evaluation and verification of the groundwater potential zones using remote sensing, geospatial techniques and field work. In this regard, thematic maps of the contributing factors such as stream networks, lineaments, lithology, slope, landcover/landuse and rainfall were generated using the Geographic Information Systems (GIS) and Remote Sensing (RS) techniques. Based on the determined recharge favorability, weighing, and overlaying, a groundwater potential of the study area was prepared. The output recharge potential map shows three zones of groundwater prospective potential: good, moderate and low constituting 25%, 69% and 6% of the study area respectively. Of them, the high and moderate zones are strongly recommended for further exploration. The geophysical, water data and transmissivity data for some water points located within the targeted area confirmed the recommended zones. The overall results reflect the effectiveness of using the remote sensing data and geospatial techniques to target areas for groundwater exploration.

Mineralogical and natural radioactivity investigations of Wadi El Reddah stream sediments

ABSTRACT Wadi El Reddah (valley), Central Eastern Desert, Egypt extends in North-South direction, it represents a semi-closed basin with only one outlet in its northern tip. Wadi El Reddah is mainly surrounded by scattered exposures in a sequence of metagabbro-diorite and metavolcanics complex in addition to wide sector of Hammamat sedimentary rocks, monzongranites of Gabal El Reddah, perthitic leucogranites of Gabal Gattar as well as swarms of post-granitic dykes. The studied sediments showed wide variation in their Uranium, Thorium, Radium (eU) and potassium (K%) contents. Uranium ranges from 5 to 51 ppm, with an average of 17.33 ppm, Th contents between 16 and 141 ppm, with 32.47 ppm as an average. Ra (eU) varies between 5 and 26 ppm with an average of 9.56 ppm. While potassium falls between 2.19% and 4.41% with an average of 3.19%. The disequilibrium conditions in the stream sediments under investigation indicated that they are mostly recent which is due to the fact that most of the radiometric measurements are lower than the chemical measurements. eTh/eU ratio values of old uranium deposits in the studied sediments suggested mineralisation in an environment of rapid deposition of rock detritus and poor weathering with the dominance of detrital radioactive minerals like thorite, samarskite, euxenite and xenotime.

QUANTIFY IMPACT OF WIND EROSION ON ORGANIC MATTER CONTENT UNDER MANAGEMENT PRACTICES, WADI EL RAML, NWCZ, EGYPT

Wind soil erosion is one of the land degradation processes in North Western Coastal Zone (NWCZ) of Egypt. It was assessed under condition of wheat crop grown on a sandy loam soil in Wadi El Raml in 2018/2019. Three tillage treatments of no-tillage (NT), minimum tillage (MT) and conventional tillage (CT) were assessed with or without organic manuring (30 m3 ha-1) combined with or without mulching (with rice straw covering 60% of soil surface).The aim of the study was assessment the impact of wind erosion on wheat yield and soil organic matter content (SOM) under different tillage practices under rainfed agriculture at Wadi El Raml in NWCZ. The highest bulk density was associated with NT. Losses (kg m-2 y-1) of about 275, 221 and 173 were shown in the CT, MT and NT treatments, respectively.The erodibility average values andloss of OM and TN were highest in the bare soil. Soil loss materials for the bare soil was higher than for the cultivated soils, which gave their the highest loss of 275 kg m-2y-1with non-manured non-mulched CT and the lowest of 16 kg m-2y-1for the manured and mulched NT. The highest wheat yield was obtained with manured and mulched CT. The results of this study showed that the use of 30 m3ha-1of organic manure and 60% of the coverage with rice straw in each cultivation type led to improving the soil content of organic matter and reducing soil loss by erosion by wind. This study emphasized the benefits of conservation tillage, such as improving bulk density as a guide to soil quality, which keeps it from degradation, as happens with conventional tillage. The study also recommended the use of conservation tillage in cultivated cereal crops for more than one season under rainfed conditions in Egypt to increase the content of soil organic matter, thus increasing crop productivity compared to the traditional tillage system to achieve sustainable agricultural production inNWCZ of Egypt.

Estimation of salt balance in salt-affected ecosystems in arid areas, Case Study: El Fayoum depression, Egypt. (Dept. C. ( Irrigation And Hydraulics ) )

El Fayoum depression is a semi-closed depression located about 100 Km southwest of Cairo-Egypt It occupies an area of about 1200 Km2. Due to the complex geological and hydrological conditions of that area, water logging problem and soil salinization affect great parts of the cultivated areas. The geological conditions are manifested in the rich content of clay in the Quaternary aquifer, the relative small aquifer thickness and the dominance of faulted and fractured limestone at the base and on the peripheries. On the other hand, the hydrological conditions include the occurrence of a thick net of irrigation system and presence of huge surface water bodies; e.g. Qarun lake and Wadi El Rayan lakes. Moreover, the groundwater depths vary from few centimeters below ground surface to 7.51 m which reflect a critical soil salt-affected problem. The present paper throws light on the salt balance of the groundwater regime. The estimation of the input and output components is carried out based on the field measurements during 2006. The estimated mean annual salt influx reaches 2.05 million tons. The Output component includes the salt efflux through the drainage network, subsurface groundwater flow and the salinity losses due to plant uptake. The estimated annual mean value of salt efflux from these three components reaches 3.8 million tons. The average annual storage component is estimated to be -1.75 million tons. The estimation of salt balance shows that the groundwater or/and soil water receive an excess of annual salt content of 1.75 million tons due to leaching process of evaporites and clay lenses during its flow from the upstream till it reaches the downstream area (Qarun Lake). Mitigation of imbalanced salt load through minimizing the losses from drainage network and using low consumed cop pattern is highly recommended.

Controlling of Saltwater Intrusion Using Injection Wells (Case Study: Quaternary Aquifer of Delta Wadi El-Arish, Sinai)

window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag("js", new Date()); gtag("config", "UA-72322659-1");

Investigation of groundwater potential using magnetic and satellite image data at Wadi El Amal, Aswan, Egypt

In this study Aeromagnetic, ground-based magnetic and satellite imagery data have been processed and analyzed to delineate surface and subsurface structures to clarify its impacts on groundwater flow direction, and to detect the thickness of groundwater aquifer’s (accumulation) in the study area. To achieve this target, an interpretation of satellite digital elevation data is processed to generate the main drainage pattern in the area to delineate the Watersheds basins and where the surface water can be accumulated. Moreover, Aeromagnetic data have been used to detect the sedimentary cover in the area, and to assess the thickness distribution of the Nubian aquifer to detect the most eligible aquifer with the largest thickness, consequently the largest amount of groundwater reserve. Also, the ground magnetic survey was conducted in Wadi El Amal to reassure the results obtained from the airborne data. Two main approach techniques were applied to the data. Firstly, the trend analysis applied to the first vertical derivative map to detect main trend analysis and faults. The second approach is to calculate the depth to the basement, which represents the base of the Nubian aquifer in the area under consideration. The final results of the main trend found as follow, the ENE-WSW, NW-SE, and NE-SW trend which found to be is the main trend. The water table in this area is about 100 m, the calculated depth to the basement in the deepest parts study area is ranging between −300 and −700 below ground surface. The integration between satellite techniques and geophysical tools can give us the whole picture of groundwater distribution and its recharge sources.

Erosion sensitivity mapping using GIS-based multicriteria analysis—case study of the semiarid Macta watershed, North-West of Algeria

The exponential rise in the natural risk related to the soil erosion and important impacts resulting in the human activities was strongly threatening the biological richness of different regions in Macta watershed located in the North-West of Algeria. This serious and complex situation has been an environmental concern in Algeria. Soil erosion depends mainly on a combination of factors such as climate (rainfall), topography, vegetation cover, type of soil, and land use (agricultural activities). The study aims are to develop a methodological approach, based on the combined use of geographic information system, remote sensing, and a set of multicriteria analysis methods such as analytical hierarchy process, PROMETHEE, dedicated to the soil erosion sensitivity mapping. The different factors are implicated in a geographic database as layers to make it easier for their implementation in a decision aid dataset such as alternatives and criteria. Results showed that the dominant classes of the fragility to erosion correspond to low and moderate levels and only less than 8% of the watershed was vulnerable to soil erosion. The analysis of the maps obtained under GIS environment for different parameters shows that the areas with a high vulnerability to erosion are located in the North-East (part of sub-watershed: wadi El Hammam, wadi Mebtouh, and wadi Fekan) and someone in the South (part of sub-watershed: wadi Taria, wadi Saida) and West (North of Mekerrela and Louza sub-watershed).

Concentrations of heavy metals and associated human health risk in unrefined salts of inland hypersaline lakes, Egypt

ABSTRACT This work investigates the heavy metal concentrations in Siwa Oasis and Wadi El Natrun unrefined salt. Sixteen samples were examined for the concentration of Cd, Co, Cr, Cu, Ni, Pb, V and Zn using inductively coupled plasma-optical emission spectrometer (ICP-OES). In addition, the major ions and mineralogical composition were investigated using X-Ray fluorescence (XRF) and X-ray powder diffraction (XRD) techniques. The result revealed that Wadi El Natrun salt contained an elevated concentration of these heavy metals when compared to those of Siwa Oasis and worldwide. Both non-carcinogenic and carcinogenic risk indicators for Siwa Oasis salt were lower than the acceptable levels; hence, consumption of these salts may not pose any significant human health risks. On the contrary, human health risk indicators values for Wadi El Natrun salt were higher than the acceptable levels; suggesting the consumption of this salt may be hazardous and can severely affect human health. The authors strongly recommend that the usage of Wadi El Natrun salt should be limited to industrial applications only.

Mid-to Late Holocene paleoclimatic changes and paleoenvironmental shifts inferred from pollen and diatom assemblages at Lake Hamra, Wadi El Natrun (Western Nile Delta, North Western Desert, Egypt)

Four palynological and three diatom zones of Mid-to Late Holocene are identified along a 370-cm-long radiocarbon dated sediment core collected in Lake Hamra at Wadi El Natrun (Western Nile Delta, Egypt). The Mid- Late Holocene between the Predynastic to Old Kingdom was terrestrial wetland habitat with high seasonal rainfall and/or Nile flood as revealed by the dominance of Cyperaceae pollen. Therefore, people gathered in and around the Nile Valley and the agricultural activities increased. During the early stage of Late Holocene coincident with the Old Kingdom to Middle Kingdom, the paleoclimate became more arid with low seasonal precipitation and/or Nile flood as reflected by the increasing abundance of Poaceae pollen and the absence of diatoms in addition to low values of TOC, TN, TS, C/S and high values of C/N. These drought conditions possibly played a role in the Old Kingdom collapsing. The late stage of the Late Holocene showed terrestrial wetland habitat with brackish conditions coupled with aquatic contribution under oxic conditions as inferred by the dominance of Typha sp. and Amaranthaceae pollens as well as the diatom assemblages. The relatively high values of TOC, C/N, C/S coupled with low values of TS and TN reveal terrestrial origin of organic matter. The Late Holocene-recent has turned into a terrestrial wetland habitat with more brackish conditions and increasing in the seasonal rainfall as supported by the marked increasing of Cyperaceae pollen. The overall increase of the Diatom Inferred Salinity (DIS) as well as the marked increasing of C/S, TN and decreasing of TOC, C/N and TS values towards the recent point to higher saline brackish wetland paleoenvironment and a terrestrial origin of the organic matter with more aquatic contribution under oxic conditions.

Separation of Thorium Ions Using Synthesized Zeolite–Phosphate Composite from Sulfate Solution

Zeolite modified with phosphate (Z/P) was synthesized and tested for Th4+ adsorption. The optimum adsorption conditions are as follows: pH 3.5, contact time of 30 min, 0.1 g of Z/P, initial Th4+ concentration of 400 mg/L, 20% tributyl phosphate (TBP) in toluene as solvent, and room temperature. Kinetics and equilibrium parameters of the Th4+ adsorption onto Z/P were determined. The maximum sorption capacity determined using the Langmuir model reached 92.59 mg/g. The Th4+ adsorption onto Z/P follows a pseudo-second-order kinetic model. Th4+ can be efficiently desorbed from the loaded Z/P with 1 M HNO3 solution. The optimized conditions were applied to the thorium adsorption from a conglomerate sandstone sample of Abu El Toyour, eastern side of Wadi El Sahu, Southwestern Sinai, Egypt.

Radioactivity and environmental impacts of ferruginous sandstone and its associating soil

ABSTRACT Spots of high radioactive anomalies were recorded in the ferruginous sandstone of the upper part of the Adedia and the lower member of Um Bogma formations at Wadi El Sahu, Sinai, Egypt. Two types of samples from Wadi El Sahu were considered, rock samples from the high radioactive ferruginous sandstone of the Adedia Formation and the lower member of Um Bogma formations and soil samples (stream sediments) from Wadi El Sahu deposits to measure the natural radiation from 238U, 226Ra, 232Th and 40K using gamma-ray spectrometry. The absorbed dose rates in air (D) obtained from the specific activities of 226Ra, 232Th and 40K were calculated consequently; annual effective dose (AEDout) and excess lifetime cancer risk (ELCR) were calculated. The results illustrated that values of 238U, 226Ra, 232Th and 40K for soil samples are much lower than the corresponding values of the mother rock. The remobilisation parameter and the difference between chemically and radiometrically measured uranium confirm uranium migration in the studied rocks.

Mapping the Roman Water Supply System of the Wadi el Melah Valley in Gafsa, Tunisia, Using Remote Sensing

In recent years, very high-resolution satellite remote-sensing tools have been progressively used in archaeological prospecting to acquire information and improve documentation. Satellite remote sensing has also benefited from technical improvements, including better spectral and spatial resolution of sensors, which have facilitated the detection and discovery of unknown archaeological areas. This paper focuses on investigations conducted using multi-spectral satellite remote-sensing data of the ancient canal systems of the Wadi el Melah Valley (WMV) in southern Tunisia. The area used to be part of a huge military defense system along the desert border. This paper describes the use of GeoEye-1 and Ziyuan-3 satellite remote-sensing data to reveal ancient Roman canals, which were part of an advanced hydraulic system devised to capture runoff water and cope with the lack of water in the area. In general, this research provides new information on some essential sections of the Roman walled defense system Limes (Fossatum) in the southern part of the empire, where we study previously undetected sites.

Rock Art and Archaeology – a Short Visit to Zolat el Hammad, Northern Sudan

The striking sandstone formation of Zolat el Hammad is located in the southern Libyan Desert, about halfway between the Middle Wadi Howar and El Atrun. The place has been known for its numerous rock engravings for more than a hundred years. Wild and domesticated animals as well as few human figures are depicted. Cattle engravings largely dominate, followed by giraffes and ostriches. In 1997 the first paintings were discovered in a small rock shelter. Very schematic bovids are drawn in red and white colour. However, even though it is one of the most remarkable rock art sites in this part of the Sahara, Zolat el Hammad has never been intensely studied. Observations on rock art and archaeology made during a short stay in 2001 are the basis for presenting an account of the area with the aim of encouraging further research on it.

Investigation of groundwater occurrences in structurally controlled terrain, based on geological studies and remote sensing data: Wadi El Morra, South Sinai, Egypt

ABSTRACT The investigations of groundwater occurrences and its recharge mechanisms in structurally controlled terrain under arid environments are necessary for developing sustainable management strategies. In current study, an interdisciplinary approach includes readily accessible climatic, geological, topographic, and hydrological datasets together with satellite imagery and field data, were employed for better understand of the groundwater regime existing under special geological setting. Our findings indicate that: 1) the Araba sandstone aquifer has maximum thickness of about 220 m in some area controlled by structural setting, particularly the basement uplift, 2) the hydrologic analyses of this basin revealed that it received a total 52.66 × 106 m3 of rainfall between July 2018 to June 2019 that led to runoff volume about 29.47 × 106 m3 with total losses amounts about 23.2 × 106 m3, 3) topographically-driven modern recharge to the structural controlled terrain (Wadi El Morra) can be occurred, and therefore further investigation related to the aquifer response to climate variability, are required. The study suggested a management plan to capitalize the available surface water potentialities of El Morra basin through establishing three lakes that store water and enhance the groundwater recharge opportunities. In addition, three regions are selected for future groundwater exploration based on geological and subsurface data.