Mathematical Modeling Of Water Quality With A Different Chemical State; Nutrients And Arid Environmental Conditions, Siwa Oasis, Egypt

Purpose: A comprehensive monitoring and evaluation study was conducted on wells, water table and drainage water for water quality index. The study aimed to achieve a sustainable integrated management for water and soil at the study area. Methodology: Assessment and evaluation of water samples were: Evaluate the physic- chemical properties; Discuss the Hydro chemical coefficient; Assessment of the appropriate use of water quality such as permeability index (PI) and Kelly's indicator (KI); Water quality identification and assessment through calculate of WQI; It was conducted various assessments of the elements within the water, such as the contamination factor (CFi); geo-accumulation index (Igeo) and the potential ecological risk index (RI). Findings: The results shown that the dominance of Na+ cation and Cl- anions due to the influence of marine sediments on water elements which resulted in increased the mention ions in drainage water> water table> wells. TDS values of wells, water tables and drainage water were no detected, 2374 to 9088 and 3641.6 to 13952mg L-1, respectively and RSC values of water samples were not significant. KI indicated that the well water is safe for drinking and the water table and drainage water are not acceptable for drinking. PI indicated that the suitability of water to be used in agriculture. WQI confirmed that the water is highly appropriated for Olive's tree and Palms cultivation. CFi indicated that the wells gave low to moderate contamination of Mn, Cu and B while, the Fe, Zn and Si concentrations were low. A very high degree of contamination by Fe, Mn, Zn, Cu and B were observed in water tables; however Si concentration was low to considerable degree. Generally, drainage water gave a very high degree of contamination with Mn, Cu, and B, whereas the concentration of Fe, Zn and Si were low, moderate and considerable degree. Analytical modeling proved that the Igeo values for Mn, Zn, Cu and Si were assigned to Class 0 for water sources at study area. RI indicated the wells and water table samples (exception of Cu was moderate to high) were slightly risk as well as the RI of drainage water samples was low risk. Contribution to theory, practice and policy: The results provided the relationships between the water resources assessment and water quality management, and to ensure their environmental reflections such as (contamination factor (CFi); geo-accumulation index (Igeo); the potential ecological risk (RI)), with the safe use of water based on its properties. Keywords: Hydro chemical coefficient; permeability index (PI); Kelly's indicator (KI); water quality index (WQI); contamination factor (CFi); geo-accumulation index (Igeo); the potential ecological risk (RI).