Study of the quality index of groundwater (GWQI) and its use for irrigation purposes using the techniques of the geographic information system (GIS) of the plain Nekor-Ghiss (Morocco)

Abstract

Groundwater is an indispensable source of water for drinking water supply, agriculture and industry worldwide. In arid and semi-arid regions, groundwater has seriously deteriorated in recent decades due to environmental changes, anthropogenic activities and marine intrusion. A total of 79 groundwater samples from the Nekor-Ghiss plain were sampled for major chemical ion analysis. These analyzes showed that the water samples were highly mineralized (>1,500 mg/L), with hardness (83.5% of the samples were very hard) and high concentrations of chemical elements, such as Cl−, Mg2+, Na+ and SO42-. To assess the quality of water in the study area for irrigation and consumption purposes, we used the quality index (GWQI) as well as a multi-criteria analysis based on “geographic information system” by assigning a weight to the different water quality parameters. Also, Piper and Durov diagram was investigated. The results of the study were focused on the water quality parameters of the collected groundwater samples, such as the sodium adsorption rate (SAR), the percentage of soluble sodium (Na%), the Residual Sodium Carbonate (RSC) and Permeability Index (PI) Majority of water samples in the study area are suitable to be used for irrigation. Magnesium Risk (MH) and Kelley’s Ratio Kelly ratio. 51.9% unsuitable samples to 59.49% good samples for irrigation purposes. Monitoring the quality and quantity of groundwater is crucial for the effective and sustainable management of this valuable resource. According to the results obtained, it appears that 92% of all the samples are located in the domain of frequent recharge waters of limestone and dolomitic aquifers, namely, Ca-Mg-HCO3. About 8% of the samples measured have a composition of the Ca-Na-Mg-HCO3 type.

Evaluation of the adaptation of groundwater quality in the Ketama Al-Hoceima region (Morocco) to agricultural irrigation

“…The study area lies between 35°0'0'' to 34°40'0''N and 4°20′0'' to 4°50′0''W. The total area covered by this zone is 956 km 2 . The study region experiences alternating dry and wet seasons because of its climate typically semi-arid.…”

“…Cl -, with high levels in water, are often considered an indicator of pollution and a marker of groundwater contamination [2]. Chloride concentration varies between 0.09 meq/L and 3.69 meq/L, with an average of 0.46 meq/L.…”

“…Severe water shortages plague the majority of nations worldwide, particularly in arid and semi-arid areas [1]. These regions are known for their erratic rainfall patterns, frequent overuse of groundwater, and high evaporation, which cause the volume of groundwater to significantly decline [2]. The security of water supply for agricultural irrigation relies heavily on groundwater resources [3].…”

Hydrochemical evolution and groundwater quality assessment of the Tinejdad-Touroug quaternary aquifer, South-East Morocco

“…Chloride, a common element, is found in groundwater from various sources, including surrounding rocks, salt is transported through rainwater, seawater intrusion, and pollution caused by domestic sewage and industrial waste (Goswami et al, 2022;Alshehri and Abdelrahman, 2023;Elkhalki et al, 2023). Water that contains a significant amount of chloride tends to emanate an unpleasant odor (Honig et al, 2020).…”