لخّصلي

Groundwater is an important commodity in Saudi Arabia.Groundwater is an important commodity in Saudi Arabia.Overall, this study justifies that continuous monitoring and management are required in this aquifer to maintain safe water quality and sustainable aquifer management in the study site.NO3- is mostly derived from anthropogenic sources (agriculture return flow, fertilizers, manures, domestic wastewater, pit lateen and septic tank leakage) while fluoride is derived from geogenic sources (fluoride minerals dissolution) in the study site.Contamination zone mapping (CZM) reveals that most of the parameters behave similarly and the groundwater is unsuitable in most of the territory except a few pockets in the southern and northern regions where groundwater is moderately suitable.In the case of HCO3-, higher values are identified in the middle and upstream regions due to geogenic sources and lower values are observed downstream due to evaporation and carbonate precipitation.Likewise, SAR (58%), KR (77%), Na% (34% good; 60% permissible), PI (8% good, 92% suitable) and MH (81%) are recommended for irrigation applications.Similarly, low sodium water (S1) is suitable for majority crops and plants whereas medium sodium water (S2) is suitable only for coarse-textured soil.The EC is generally < 5000 uS/cm in 68% of samples and elevated values are inferred in the coastal region, which seems to be due to evaporation and evaporite dissolution.The examination of drinking water appropriateness suggests that more than 90% of samples surpassed the recommended limit provided by national (SASO) and international (WHO) organisations and were not recommended for oral consumption.For example, Check dams and surface storage structures are important options to enhance the aquifer recharge and, consequently, reduce the salinity and other ions in the groundwater.Thus, groundwater quality evaluation along with contamination zone mapping was performed in the Kulais region, KSA.There is a large variation in water quality, inferred from EC, TDS and TH, in this aquifer and the water quality is controlled by multiple processes and sources in the study site.The water is neutral to slightly alkalineNO3- is mostly derived from anthropogenic sources (agriculture return flow, fertilizers, manures, domestic wastewater, pit lateen and septic tank leakage) while fluoride is derived from geogenic sources (fluoride minerals dissolution) in the study site.In the case of HCO3-, higher values are identified in the middle and upstream regions due to geogenic sources and lower values are observed downstream due to evaporation and carbonate precipitation.In the study region, the major water type is Ca-Mg-Cl (75%) followed by Na-Cl.

Groundwater is an important commodity in Saudi Arabia. Thus, groundwater quality evaluation along with contamination zone mapping was performed in the Kulais region, KSA. The GWL in the study site is generally shallow (< 10 mbgl) and deepwater level is noticed in the downstream region. Groundwater flows to West and discharges to the Red Sea. The nexus between GWL and EC suggests that the salinity increases along with groundwater flow direction towards Red Sea. The EC is generally < 5000 µS/cm in 68% of samples and elevated values are inferred in the coastal region, which seems to be due to evaporation and evaporite dissolution. The water is neutral to slightly alkaline. There is a large variation in water quality, inferred from EC, TDS and TH, in this aquifer and the water quality is controlled by multiple processes and sources in the study site.

In the study region, the major water type is Ca-Mg-Cl (75%) followed by Na-Cl. Wadi waters also show similar water types and are derived from groundwater discharge (baseflow). Moreover, the Ca-Mg-Cl type indicates that the groundwater is affected by the surface contaminations in this aquifer. The spatial distribution of major ions explains that groundwater quality in the central region is less mineralized compared to upstream and downstream regions. Concentrations are increasing from the middle stream to downstream and higher values are recorded in the downstream wells. In the case of HCO3-, higher values are identified in the middle and upstream regions due to geogenic sources and lower values are observed downstream due to evaporation and carbonate precipitation. The distribution of NO3- and F- do not show a particular trend and low values occurred in the northern region. NO3- is mostly derived from anthropogenic sources (agriculture return flow, fertilizers, manures, domestic wastewater, pit lateen and septic tank leakage) while fluoride is derived from geogenic sources (fluoride minerals dissolution) in the study site.

The examination of drinking water appropriateness suggests that more than 90% of samples surpassed the recommended limit provided by national (SASO) and international (WHO) organisations and were not recommended for oral consumption. Irrigation suitability assessment explains that only 38% of samples belong to the fair class while the remaining are poor to unsuitable for irrigation based on salinity. Likewise, SAR (58%), KR (77%), Na% (34% good; 60% permissible), PI (8% good, 92% suitable) and MH (81%) are recommended for irrigation applications. USSL classification illustrates that water samples are clustered only in three zones such as C3S1 (34%), C4S2 (24%) and C5S3 (21%). Water samples plotted in C5 are not recommended for irrigation whereas C3 and C4 are suitable for high permeability soil and crops with salt tolerant. Similarly, low sodium water (S1) is suitable for majority crops and plants whereas medium sodium water (S2) is suitable only for coarse-textured soil. Groundwater usability for livestock and poultry application is assessed by salinity and 68% of samples are recommended for livestock and poultry uses. Further, multiple parameters assessment (EC, NO3-, Mg2+ and F-) suggest that 47% of samples are recommended to use livestock and poultry.

Groundwater is an important commodity in Saudi Arabia.Overall, this study justifies that continuous monitoring and management are required in this aquifer to maintain safe water quality and sustainable aquifer management in the study site.NO3- is mostly derived from anthropogenic sources (agriculture return flow, fertilizers, manures, domestic wastewater, pit lateen and septic tank leakage) while fluoride is derived from geogenic sources (fluoride minerals dissolution) in the study site.Contamination zone mapping (CZM) reveals that most of the parameters behave similarly and the groundwater is unsuitable in most of the territory except a few pockets in the southern and northern regions where groundwater is moderately suitable.In the case of HCO3-, higher values are identified in the middle and upstream regions due to geogenic sources and lower values are observed downstream due to evaporation and carbonate precipitation.Likewise, SAR (58%), KR (77%), Na% (34% good; 60% permissible), PI (8% good, 92% suitable) and MH (81%) are recommended for irrigation applications.Similarly, low sodium water (S1) is suitable for majority crops and plants whereas medium sodium water (S2) is suitable only for coarse-textured soil.The EC is generally < 5000 uS/cm in 68% of samples and elevated values are inferred in the coastal region, which seems to be due to evaporation and evaporite dissolution.The examination of drinking water appropriateness suggests that more than 90% of samples surpassed the recommended limit provided by national (SASO) and international (WHO) organisations and were not recommended for oral consumption.For example, Check dams and surface storage structures are important options to enhance the aquifer recharge and, consequently, reduce the salinity and other ions in the groundwater.Thus, groundwater quality evaluation along with contamination zone mapping was performed in the Kulais region, KSA.There is a large variation in water quality, inferred from EC, TDS and TH, in this aquifer and the water quality is controlled by multiple processes and sources in the study site.The water is neutral to slightly alkaline