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Tétel Szabadon hozzáférhető Adsorption of Sodium in an Aqueous Solution in Activated Date Pits(2023) Rahal, Zakaria; Abderrahmane, Khechekhouche; Barkat, Ayoub; Smolyanichenko, Alla Sergeevna; Chekima, HamzaTétel Korlátozottan hozzáférhető Assessment of Complex Terminal Groundwater Aquifer for Different Use of Oued Souf Valley (Algeria) Using Multivariate Statistical Methods, Geostatistical Modelling and Water Quality Index(2021) Barkat, Ayoub; Bouaicha, Foued; Bouteraa, Oualid; Mester, Tamás; Ata, Behnam; Balla, Dániel Zoltán; Rahal, Zakaria; Szabó, GyörgyTétel Szabadon hozzáférhető Assessment of Spatial Distribution and Temporal Variations of the Phreatic Groundwater Level Using Geostatistical Modelling: The Case of Oued Souf Valley-Southern East of Algeria(2022) Barkat, Ayoub; Bouaicha, Foued; Mester, Tamás; Debabeche, Mahmoud; Szabó, GyörgyTétel Szabadon hozzáférhető Evaluation of climatic conditions from 1978 to 2020 of Oued Souf Valley (Southern East of Algeria)(2023) Barkat, Ayoub; Bouaicha, Foued; Rahal, Zakaria; Mester, Tamás; Szabó, GyörgyTétel Szabadon hozzáférhető Evaluation of climatic conditions from 1978 to 2020 of Oued Souf valley (Southern East of Algeria)(2023-06-30) Barkat, Ayoub; Bouaicha, Foued; Rahal, Zakaria; Mester, Tamás; Szabó, GyörgyIn this research, a climatic synthesis was built to assess the climatic parameters of the Oued Souf Valley through the meteorological data obtained from Guemar station (airport). It was revealed that the hydrological year of Oued Souf Valley is branded by the presence of a dry period and the total absence of a wet period over the year, even during January, when it was observed to have the lowest temperature and highest precipitation, which classified it as a Saharan climate (Hyper arid). The irregularity and the scarcity of precipitation, high temperatures and extremely high evapotranspiration had significant repercussions on surface runoff and infiltration which implies a high pressure on the water resources of Oued Souf valley and may disrupt the future socioeconomic project and increase the damage of natural drought and desertification.Tétel Szabadon hozzáférhető Hydrochemical assessment of groundwater using multivariate statistical methods and water quality indices (WQIs)(2024) Hamma, Bellal; Alodah, Abdullah; Bouaicha, Foued; Bekkouche, Mohamed Faouzi; Barkat, Ayoub; Hussein, Enas E.Tétel Szabadon hozzáférhető Hydrochemical Assessment of the Kisköre Reservoir (Lake Tisza) and the Impacts of Water Quality on Tourism Development(2023) Mester, Tamás; Benkhard, Borbála; Vasvári, Mária; Csorba, Péter; Kiss, Emőke; Balla, Dániel Zoltán; Fazekas, István; Csépes, Eduárd; Barkat, Ayoub; Szabó, GyörgyTétel Szabadon hozzáférhető Inequalities in Regional Level Domestic CO2 Emissions and Energy Use: A Case Study of Iran(2022) Ata, Behnam; Pakrooh, Parisa; Barkat, Ayoub; Benhizia, Ramzi; Pénzes, JánosTétel Szabadon hozzáférhető Integrated Assessment of the Groundwater Resources of the Northwest Sahara Aquifer System: Case of the Oued Souf ValleyBarkat, Ayoub; Szabó, György; Bouaicha, Foued; Földtudományok doktori iskola; Természettudományi és Technológiai Kar::Földtudományi Intézet::Tájvédelmi és Környezetföldrajzi TanszékSince the early 1980s, various regions in northern Algeria's Sahara have been grappling with rising groundwater levels. Among these regions, the Oued Souf Valley has been particularly affected by this phenomenon due to a combination of natural and anthropogenic factors, which have exacerbated the north west Sahara aquifer system pollution. In this thesis, I employed a comprehensive methodology structured around hydrogeochemical analysis, the application of water quality indices for drinking, irrigation, and pollution detection, multivariate statistical analysis, and spatial analysis. This approach aimed to investigate the Northwest Sahara Aquifer System both qualitatively and quantitatively by identifying pollutants within the aquifer, ensuring water safety for consumption and use, and assessing the phreatic groundwater aquifer's condition. Consequently, in this dissertetion, an evaluation of the vertical drainage system performance and its impact on the phreatic groundwater level stabilization has been performed by mapping the water table of the phreatic groundwater level using geostatistical modelling using Ordinary kriging (OK) interpolation method, which has been applied to analyze the spatial and temporal structure of groundwater level fluctuation. Meanwhile, hierarchical cluster analysis (HCA) was applied for grouping the wells based on the groundwater fluctuations for 2008, 2009, 2014, 2016, 2018, and 2021. However, the vertical drainage system reflected a significant decline of groundwater from 2009 to 2018 due to the important drained volumes through it but another rising phenomenon might be threatening the region in the near future, and this is what was indicated in the 2021 groundwater level data. Cluster analysis has generated four groups based on their fluctuation means that are increasing from the first group to the fourth group ascendingly. The first cluster grouped the drains that have a shallow depth (average mean of 5.91 mbgl) and declined over the clusters. The clusters are spatially combined with significant separation of the fourth cluster which represents the deepest group (12.89 mbgl). Based on this research, several factors are influencing the stability of the phreatic groundwater level and even the performance of the drainage system, the most important of which is the overexploitation from deep groundwater reservoirs such as complex terminal and continental intercalary (in drinking and irrigation) and even the illegal use of the phreatic groundwater with important quantities for irrigation and illegal industries. On the other side, using complex hydrogeochemical and geostatistical methods on the collected phreatic groundwater samples, it was revealed that groundwater temperatures of the phreatic aquifer ranged between 25 and 31.40°C, potentially influencing quality through microbial proliferation and reduced gas solubility. The pH values fluctuated between 6.78 and 8.57. While most samples fell within the World Health Organization's (WHO) recommended limits, approximately 32% exhibited slightly acidic conditions. EC values extended from 3100 to 7500 µs/cm, surpassing the WHO's guidelines for potable water. Elevated EC suggests a high concentration of total dissolved solids, which similarly exceeded WHO standards in most samples. Turbidity levels exhibited substantial variation, compromising aesthetic quality and necessitating treatment prior to consumption. Some samples were identified as turbid or relatively turbid. The concentrations of Ca, Mg, Na, K, and Cl were predominantly high, frequently exceeding WHO's drinking water thresholds. Specific samples demonstrated varying compliance with these standards. Moreover, numerous samples surpassed WHO limits for NO3, NO2, and NH4, suggesting potential contamination from agricultural runoff, sewage, or industrial effluents. Concentrations of F, SO4, and PO4 exceeded WHO guidelines in certain samples, whereas sulfate levels were generally within acceptable limits. DO, COD, and BOD varied among samples, reflecting differing degrees of biodegradability and pollution. Fecal and total coliform levels were elevated in some samples, indicating significant contamination. Employing various indices such as the National Sanitation Foundation Water Quality Index, Groundwater Pollution Index, and Nitrate Pollution Index, the study revealed poor water quality, substantial groundwater pollution, and diverse levels of nitrate contamination. Furthermore, fourteen hydrochemical parameters were analyzed from phreatic groundwater samples to compute the water quality index for drinking suitability analysis. These parameters, evaluated against the WHO limits established in 2011, included Ca, Mg, Na, K, F, NO3, HCO3, Cl, turbidity, EC, TDS, SO4, PO4, and pH. Across all 28 samples obtained from the studied aquifer, the findings revealed that the majority of the samples were classified as having good water quality. Additionally, two samples were categorized as excellent, three as poor, two as very poor, and four as unfit for drinking water utilization. The assessment of twenty-eight groundwater samples from a phreatic aquifer for irrigation suitability used various indices. Of these, nineteen were excellent for irrigation, and nine were good, based on the percentage of sodium (% Na) values. All twenty-eight samples were rated excellent according to the Sodium Adsorption Ratio (SAR), suitable for most soil types. Regarding total hardness (TH), four samples were moderately hard, twenty-two were hard, and two were very hard. The Magnesium Hazard (MH) index showed eighteen samples as suitable for irrigation, while ten were unsuitable. The Permeability Index (PI) indicated that all twenty-eight samples were unsuitable for irrigation. However, other indices like Kelley's Ratio (KR), Exchangeable Sodium Percentage (ESP), Residual Sodium Carbonate (RSC), and Relative Bicarbonate Sodium Concentration (RBSC) classified all samples as suitable. According to the Ps index, all samples were rated as injurious to unsatisfactory. The Ka index revealed four samples with permissible quality and twenty-four with doubtful quality for irrigation. Finally, the K index results showed ten samples of excellent quality, eight of good quality, five of injurious quality, and five as unsuitable for irrigation. On the other hand, two distinct groups of groundwater samples were identified based on HCA. The first group included twenty-one wells, while the second group consisted of seven wells. The key distinguishing factors between these groups appeared to be the concentrations of Na, K, F, NO3, HCO3, Cl, and EC, which exhibited a notable increase from the first group to the second. Notably, the samples in the first group did not exceed WHO limits for F and NO3 concentrations, indicating lower vulnerability to NO3 and F contamination. These samples were concentrated primarily within the main municipality of El Oued. Conversely, the second group of samples exhibited higher vulnerability in terms of Na, K, F, NO3, HCO3, Cl, and EC. This area was situated on the outskirts of El Oued, Debila, and Guemar municipalities, near agricultural areas. This analysis provides valuable insights into the spatial distribution and variations in hydro-chemical properties across the study area, offering important information for groundwater resource management and monitoring, especially in relation to potential contamination sources and vulnerability. Furthermore, the applied spatial analysis identified and emphasized on the existence of three typical spatial patterns within the parameters under study. Through applied spatial analysis, it was observed that peri-urban and agricultural areas are characterized by elevated levels of EC, Na, K, Cl, HCO3, PO4, and DO. In contrast, higher concentrations of Ca, Mg, F, NO2, and NH4 were discovered predominantly in urban areas. Additionally, NO3, SO4, BOD, and COD exhibited high levels in both agricultural and urban regions. The hydro-chemical analysis of phreatic groundwater samples revealed several key findings: Major Ion Abundances: The major ion abundances in both generated groups of phreatic groundwater samples followed an order of Ca > Mg > Na+K and Cl > SO4 > HCO3+ CO3. The hydrochemical facies in the phreatic groundwater exhibited slight differences between the first and the second group. The first group was characterized by Ca-Mg-Cl-SO4 type and Ca-Cl type waters, while the second group included Ca-Mg-Cl-SO4, mixed Ca-Na-HCO3, and Cl type waters. The Chadha plot revealed that all the samples in both groups belonged to the reverse ion-exchange Ca-Mg-Cl/SO4 water type, indicating Ca-Mg-Cl type, Ca-Mg dominant Cl type, or Cl-dominant Ca-Mg type waters. Gibbs diagrams illustrated that the majority of the total samples from the phreatic aquifer were in the evaporation-crystallization dominance (salinization) field, suggesting a significant influence of evaporation-crystallization processes. However, two samples were in the rock-dominance weathering field. The chloro-alkaline indices revealed that some samples exhibited positive values, indicating the exchange of Na+ and K+ from the groundwater with Mg2+ and Ca2+ of the rocks (base-exchange reaction), while others had negative indices, indicating the opposite exchange. The normalized Na graphs suggested a slight tendency towards silicate weathering and evaporate dissolution, as well as a slight tendency towards silicate weathering and carbonate dissolution in the phreatic groundwater samples. The saturation indices indicated that Anhydrite, gypsum, Halite, and Sylvite were completely dissolving, while Fluorite was dissolving in all samples except one. Aragonite, Calcite, Dolomite, and Hydroxyapatite were found to be dissolving in some samples, while other samples were characterized by the precipitation of these minerals. Mineral stability diagrams revealed that all samples fell within the Ca-smectite stability field, with a concentration in the Kaolinite field, indicating the role of these minerals in the groundwater chemistry of the phreatic aquifer. Also, as a one of the major parts of this thesis, contamination levels and the spatial pattern identification, as well as human and environmental health risk assessments of the heavy metals in the phreatic groundwater aquifer of the Oued Souf Valley were investigated for the first time. The applied methodology comprised a combination of heavy-metal pollution indices, inverse distance weighting, and human health risk assessment through water ingestion on samples collected from fourteen monitoring wells. The contamination trend in the phreatic aquifer showed Al > B > Sr > Mn > Fe > Pb > Ni > Cr > Ba > Cu > Zn. Similarly, the enrichment trend was Al > B > Sr > Mn > Ni > Pb > Cr > Ba > Cu > Zn. Ecologically, most of the analyzed metals reflected a low potential ecological risk, except for two wells, S13 and S14, which represented a considerable and high ecological risk in terms of Pb. According to the applied grouping method, the samples in the first group indicated a lower risk of contamination in terms of heavy metals due to their lower concentration compared to the second group. This makes the area containing the second group’s samples more vulnerable in terms of heavy metals, which could affect urban, peri-urban, and even agricultural areas. All of the samples (100%) indicated the possibility of potential health risks in the case of children. While six samples showed that the non-cancer toxicity risk is considered low, the rest of the samples had high Hazard Index (HI) values, indicating the possibility of health risks occurring in the case of adults. The constructed vertical drainage system is acting as a supporter and accelerator of the pollution levels in the shallow groundwater aquifer. This is due to its contribution to the penetration of different pollutants into this aquifer system, depending on the residence time of the water, which appears to be long within the drainage system. In terms of deep aquifers, a comprehensive study has been conducted to assess the hydrogeochemical evolution of the deep groundwater aquifers such as the complex terminal groundwater aquifer in Oued souf valley for drinking and irrigation purposes. To achieve this, 49 groundwater samples from the complex terminal were examined and treated concurrently with multivariate statistical methods, geostatistical modeling and the WQI (water quality index). Focusing on the physico-chemical parameters, Q mode clustering analysis detected four major water groups, where the mineralization augmented from group 1 to group 4. The hydro-chemical type was the same, Ca-Mg-Cl-SO4 for all the groups. Calcite, dolomite, anhydrite, and gypsum would be the dominant reactions with the undersaturation of evaporates minerals, based on geochemical modeling, while the carbonate minerals are precipitating. Geostatistical analysis using ordinary Kriging demonstrated the exponential semi-variogram model fitted for EC, Ca, Mg, K, HCO3, Cl, and SO4. At the same time, the rational quadratic model was the best-fitted semi-variogram model for Na and NO3. EC, SO4, and NO3 have a strong spatial structure, while Ca, Na, K, and HCO3 have a moderate spatial structure. Moreover, there was a weak spatial structure for Mg and Cl. The WQI shows that CT (complex terminal groundwater aquifers) in many of the wells have poor to very poor water quality (55.10%), with only a small fraction exhibiting good quality. Only two samples were deemed unfit for drinking and their quality for irrigation fluctuates from good to moderate quality although its high mineralization. Furthermore, temporal changes in a complex terminal groundwater aquifer have been analyzed, particularly focusing on various water quality parameters such as pH, Electrical Conductivity (EC), total hardness, turbidity, and the concentrations of different ions and elements. The analysis reveals fluctuations in pH values with potential seasonal patterns, as well as outliers that may result from factors like contamination events or measurement errors. EC values indicate variations and frequent exceedance of WHO limits for drinking and irrigation purposes. Total hardness remains consistently high, while turbidity stays within WHO limits. Concentrations of Ca, Mg, Na, K, Fe, NH4, Cl, SO4, HCO3, NO2, PO4, and NO3 vary over the studied years, with some exceeding WHO limits. These variations may be linked to geological factors and potential communication with shallow aquifers. The comprehensive hydrogeochemical analysis of groundwater samples from the continental intercalary aquifer revealed several key findings. The temperature and pH generally met the 2011 World Health Organization (WHO) standards for drinking water, but elevated EC, TDS, and turbidity levels indicated brackish water with mineralization. Major cations (Ca, Mg, Na, and K) and anions (Cl, SO4, and HCO3) exceeded WHO standards, while NO3 levels were within acceptable limits. PO4 levels surpassed WHO thresholds in all samples, and some samples exhibited elevated NH4 levels. CI-1 showed elevated Fe levels exceeding WHO standards. Different major ion abundance orders indicated varying water types in the samples. Groundwater chemistry suggested the dissolution of calcite and ion exchange of Ca and Mg for Na and K. Saturation indices indicated mineral dissolution and precipitation. The water quality index classified all three samples as having "good" water quality for potable use, but irrigation suitability varied, with some samples being suitable and others doubtful or unsuitable. Nitrate levels remained below WHO standards, indicating a lack of nitrate pollution. CI-1 exhibited a higher degree of pollution compared to CI-2 and CI-3 based on the groundwater pollution index. Overall, the study provides insights into the hydrogeochemical dynamics and suitability of continental intercalary groundwater for various uses, highlighting variations in water quality and potential challenges for potable and irrigation purposes. The analysis of the temporal changes in the complex terminal groundwater quality over the years presents several noteworthy trends. The pH levels have remained relatively stable, indicating slightly alkaline water, with an uptick in variability in the last two years. EC has been on a decline, pointing towards a reduction in water mineralization, with the initial years showing greater extremes. Turbidity has decreased, suggesting the water is becoming clearer, a trend that is supported by the decline in total dissolved solids. Cl and Na concentrations have dropped, although Na levels exhibit considerable annual fluctuations. A worrying trend is observed with K and NO3 levels, both of which have spiked in 2020, hinting at potential contamination issues. The rise in NO3 could be linked to agricultural runoff or interaction with shallower aquifers. NH4 levels are generally low but rose in 2020, potentially indicating organic pollution. PO4 concentrations have been consistently low, which helps in preventing eutrophication. Ca shows a decreasing trend with considerable year-to-year variation, while Mg levels have been relatively stable with a marginal downward trend. NO2 levels have been inconsistent, raising concerns about nitrogen compound contamination. SO4 levels have varied, with a peak in 2017, reflecting changing geochemical processes. HCO3 concentrations are low and on a downward trajectory, which could impact the water's buffering capacity. Lastly, Fe concentration has generally decreased, except for a significant outlier in 2019. These findings collectively suggest that while some aspects of water quality are improving, there are emerging concerns, particularly related to potential contamination from agricultural and organic sources. On the other hand, the analysis of the continental intercalary aquifer's hydrochemistry from 2012-2021 reveals fluctuations in pH and consistently high TH, indicating poor water quality for consumption. EC and turbidity levels often exceeded WHO standards. Variability was observed in Ca and Mg levels, with Mg exceeding WHO limits in most years. Data gaps limited the analysis of Na, K, and Fe. Cl and SO4 concentrations were consistently above drinking water standards, while NO3 remained within safe levels. PO4 levels varied, occasionally surpassing safe limits. The present dissertation discusses highly important results obtained from the analysis conducted on several horizons of the aquifer system in the Oued Souf Valley, which represents a part of the Northwest Sahara Aquifer System. The results obtained and discussed throughout this dissertation can contribute to drawing attention and increasing the awareness of water experts, both locally and globally, about the consequences of inadequate water management and the negligence in implementing integrated water resource management, especially in arid regions with substantial groundwater resources such as the Oued Souf Valley. While this thesis provides significant insights into groundwater resources in arid regions, it is important to acknowledge several limitations. The number of samples collected for hydrogeochemical analysis of the Phreatic, Complex terminal, and Continental Intercalary groundwater aquifers was insufficient to study the temporal changes in their quality. This necessitates continuous analysis of these aquifers in the future. A larger sample size is required to understand and confirm the origins of mineralization and pollutants (physicochemical, bacteriological, and heavy metals), which will be achieved by employing additional methods not utilized in this research. As a further step for future research, extensive investigations must be conducted on the three groundwater aquifers to more thoroughly assess their quality, with a focus on the phreatic groundwater aquifer, including its vertical drainage system. Additionally, the introduction of new and modern techniques such as deep and machine learning techniques (Support Vector Machines (SVMs), Gradient Boosting Machine, and M5 and M5-cubist Convolutional Neural Networks) will be essential. These will be used alongside several modified DRASTIC methods to estimate pollution levels and identify areas most vulnerable to pollution. An assessment of soil contamination resulting from rising phreatic groundwater levels will represent a completely novel research axis for my future work.Tétel Szabadon hozzáférhető Phytotoxicity Assessment of Oat Seeds Using Purified Water Treated with Palm Leaves and Date Pits(2024) Rahal, Zakaria; Abderrahmane, Khechekhouche; Chekima, Hamza; Barkat, Ayoub; Smolyanichenko, Alla SergeevnaTétel Szabadon hozzáférhető The Integrated Use of Heavy-Metal Pollution Indices and the Assessment of Metallic Health Risks in the Phreatic Groundwater Aquifer-The Case of the Oued Souf Valley in Algeria(2023) Barkat, Ayoub; Bouaicha, Foued; Ziad, Sabrina; Mester, Tamás; Sajtos, Zsófi; Balla, Dániel Zoltán; Makhloufi, Islam; Szabó, György