Kotayba Al-Youzbakey’s scientific contributions

Groundwater is an important resource, especially in areas where water resources do not meet the requirements of life. Therefore, population centers in areas far from rivers are linked to the quantity and quality of groundwater available. The study area represents a large part of the eastern part of Nineveh Governorate, which is dotted with small cities and villages with population and agricultural activity. The quantity and quality of groundwater are related to the nature of the reservoir rocks in the region, which are mainly represented by the Pila Spi Formation, composed of dolomite limestone, the Fat’ha Formation, composed of periodic successions of marl, limestone, and gypsum, and the Injana Formation, composed of periodic successions of sandstone, siltstone, and clay. The quality of the rocks exposed in the study area, especially at the feet of the Bashiqa and Ain Al-Safra mountains, and the ability of the minerals that make up them to dissolve in conditions of weathering and erosion also affect the water content of dissolved salts. The water quality index (WQI) was calculated to determine its suitability for civil use based on the physical (pH, E.C, T.D.S and T.H) and chemical (Ca2+, Mg2+, Na+, K+, HCO3-, SO42-, Cl- and NO3-) specifications. In light of this, the distribution of wells was determined according to their specifications. In general, there were six regions; The first in the northern part has excellent water, the second in the south has good water, the third in the south has unsuitable water, and the fourth area, which represents the area confined between the city of Mosul and Mount Bashiqa, has poor water quality, while the area adjacent to Ain Al-Sufra Mountain is classified as having good water quality, while The area located to the southwest towards the Tigris River is of very poor quality. There are sites for wells whose specifications vary according to the type of activity there.

The study of water geochemistry is of great importance in evaluating surface water sources, and the physical and chemical properties are among the most important criteria adopted to determine the suitability of water for various uses, including irrigation, The term irrigation water quality coefficient expresses the suitability of water. Water quality is affected by natural processes and human activities.A geochemical study was carried out to evaluate the water quality for irrigation and other uses of the main valleys (Al-Rashediya, Al-Kharrazi, Al-Khosar, Al-Danffilli, Al-Shor) lies on the left side of Mosul city. for the purpose of evaluating its quality and suitability for irrigation purposes. 48 samples were collected, and field and physical measurements were conducted, which included temperature, pH, electrical conductivity, total dissolved salts, total hardness, and turbidity. The concentrations of the main ions were also measured and it was found that the dominant positive ions are) Ca2+>Mg2+>Na+>K+ ), and negative ions(HCO3->SO42->Cl->NO3- ), The classification developed from the Piper water scheme of the studied valleys showed that the water quality in Al-Rashediya Valley is (Ca-Mg-SO4) type , the water quality in both the valley of Al-Khosar and Al-Shor is of the type (Ca-Mg-SO4-Cl). The water quality in Al-Kharrazi Valley is of the type (Alkaline earths exceed alkali metals). While the water quality in Al-Danffilli Valley is of the type (Ca, Mg, HCO3). The classifications of Sodium Adsorption Ratio (SAR), Magnesium Adsorption Ratio (MAR), Sodium Saturation Percentage (SSP), Wilcox scheme, Residual Sodium Carbonate (RSC)