Mohamed Yousif

The integration between the environmental chemistry and remote sensing data can be considered a new approach introduced through this study to investigate and monitor the ambient environment. The research findings relative to chemical and bacteriological analyses show disparities in the elements' concentrations of wastewater (influent, effluent, seepage, and overflow) with a salinity range between 3539 and 9509 mg/l. Groundwater salinity values range from 3680 to 11471 mg/l, NO3 (1.4 to 11.2 mg/l), viable bacteria (16 to 70), COD (70 to 125 mg/l), BOD (15 to 40 mg/l), and TOC (90 to 192 mg/l). These data reveal the penetration of the wastewater till a depth of 125 m. To discuss the impact of wastewater on the carbonate landform, a new chemical approach has been presented. In this approach, the water chemistry was expressed by their hypothetical salts, whereas the rocks were expressed via their main chemical constituent (CaCO3, 95%). The approach provides the possibility of creating all the potential chemical reactions with their equations. The obtained equations indicate possibility of rock dissolution, crumbling and continuous release of CO2 (a greenhouse gas). The results of the study led to recommendations to protect the region's unique landform and work to resist environmental degradation.

The desert environment is a clean, dynamic system due to its remoteness from human interventions. Yet, sometimes it is approached by anthropogenic activities that change its balanced ecosystem. The present study states that the non-planned construction of wastewater plants has affected the environment and led to water resource deterioration. The presented approach is based on the integration of hydrogeologic data together with remote sensing and GIS applications as well as statistical, chemical, biochemical, and bacteriological analyses of water samples. The groundwater showed high salinity values (up to 13,236 mg/l) where it is extracted from two coastal aquifers; the Middle Miocene aquifer represents the main one, while the Pleistocene aquifer is of limited use. The obtained results reveal the existence of pollution indicators in both stored rainwater and groundwater where the colony bacteria, NO₃, chemical and biological oxygen demands, and total organic carbon exceed the permissible limits. The satellite images acquired between 2003 and 2021 demonstrated a land use change through the construction of a wastewater plant with two forests that led to the spreading of the partially treated water over the Marmarica Plateau. The photogeological lineaments are extracted where the plateau is affected by many faults (NE-SW, NW–SE, and E-W) that facilitate surface–groundwater interaction. The results indicate that the studied groundwater becomes vulnerable to the existing pollution sources, with the possibility of being affected by climate change and saltwater intrusion. Therefore, this integrated approach is presented to assess the current environmental problems and suggests a strategy to mitigate the pollution hazards.

This study is focused on developing an approach for spatial mapping of groundwater by considering four types of factors (geological, topographical, hydrological, and climatic factors), and by using different bivariate statistical models, such as frequency ratio (FR) and Shannon’s entropy (SE). The developed approach was applied in a fractured aquifer basin (Ameln Basin, Western Anti-Atlas, Morocco), to map the spatial variation of groundwater potential. Fifteen factors (15) influencing groundwater were considered in this study, including slope degree, slope aspect, elevation, topographic wetness index (TWI), slope length (LS), topographic position index (TPI), plane curvature, profile curvature, drainage density, lineament density, distance to rivers and fault network, normalized difference vegetation index (NDVI), lithology, and land surface temperature (LST). The potential maps produced were then classified into five classes to illustrate the spatial view of each potential class obtained. The predictive capacity of the frequency ratio and Shannon’s entropy models was determined using two different methods, the first one based on the use of flow data from 49 boreholes drilled in the study area, to test and statistically calibrate the predictive capacity of each model. The results show that the percentage of positive water points corresponds to the most productive areas (high water flow) (42.86% and 30.61% for the FR and SE models, respectively). On the other hand, the low water flows are consistent with the predicted unfavorable areas for hydrogeological prospecting (4.08% for the FR model and 6.12% for the SE model). Additionally, the second validation method involves the integration of 7200 Hz apparent resistivity data to identify conductive zones that are groundwater circulation zones. The interpretation of the geophysical results shows that the high-potential zones match with low apparent resistivity zones, and therefore promising targets for hydrogeological investigation. The FR and SE models have proved very efficient for hydrogeological mapping at a fractured basement area and suggest that the northern and southern part of the study area, specifically the two major fault zones (Ameln Valley in the north, and the Tighmi-Tifermit Valley in the south) has an adequate availability of groundwater, whereas the central part, covering the localities of Tarçouat, Boutabi, Tililan, and Ighalen, presents a scarcity of groundwater. The trend histogram of the evolution of positive water points according to each potentiality class obtained suggests that the FR model was more accurate than the SE model in predicting the potential groundwater areas. The results suggest that the proposed approach is very important for hydrogeological mapping of fractured aquifers, and the resulting maps can be helpful to managers and planners to generate groundwater development plans and attenuate the consequences of future drought.

Monitoring of air pollutants using satellite data has been largely improved over the past few decades, which can provide deeper insights into the effects of anthropogenic activities on the air quality. The observations and measurements of atmospheric NO₂ are poorly investigated in North Africa, therefore, the current study applied a multi-proxy approach to better understand of the ambient environment. This approach is based on satellite observations, chemical and biological analyses, and investigative information during fieldworks. The Aura satellite provides the basic data for the current study with fine resolution of atmospheric NO₂ and O₃ concentrations. The obtained results reveal noticeable increases of atmospheric NO₂ values since the 2011, where its emission reaches the peak during summer season that is characterized by high anthropogenic activities. The study area has many sources for NO₂ emissions, such as the urban region, traffic, as well as the NH₃ emission that is in turn converted to NO_2. Although the discharged and spreading wastewater (80,000 m³/day in summer) has a limited role in NO₂ emissions, it represents an indicator of the anthropogenic activities. The wastewater analyses confirm the occurrence of nitrate (NO₃⁻), nitrite (NO₂⁻), and ammonia (NH₄⁺), which provide an appropriate condition for NO₂ release. The analyses of multi-climate datasets (previous records and the expected scenarios) reveal an increase of temperature accompanied by decrease of precipitation which confirmed the existence of climate change. Therefore, the study presents a set of suggestions to mitigate the release of NOx gases and achieve Net-Zero emissions.

The study of the mineral compositions of a definite area is very important to discover interesting elements. In this work, four rock samples were provided from the surface and six rock samples were obtained from different depths of groundwater wells. The area of study belongs to the western side of El-Minia, the Western-Desert of Egypt. The types of collected rock samples are limestone, dolomitic-limestone, and gravelly-sandstone for surface rock samples while the subsurface rock samples are limestone, clay, and gravelly-sandstone. A Neutron Activation Analysis (NAA) is utilised to describe the mineralogical compositions of these samples. The NAA is determining seventeen elements in the surface rock samples including two rare earth elements REEs while it is detected twenty-three elements in the subsurface rock samples including six REEs. The results indicated that the main elements of surface rock samples are (Fe, Na, Al, Ca, K, and Mg) while subsurface samples are (Ca, Fe, Al, Mg, and K) with different concentrations. The data also indicated that the subsurface samples contain (REEs) at reasonable levels than surface samples. The correlation analysis was applied to evaluate the inter-element relationships in the studied area. The obtained results were compared with the corresponding recent studies and it was found that the results agree with previous studies to a large extent.