The process of groundwater exploitation, which involves drawing water from subsurface aquifers, is often used to address surface water shortages. Because of population expansion and poor management approaches, overexploitation of groundwater continues to be a major issue in many nations despite the installation of management measures [1]. Actually, to provide a steady supply of high-quality water for an array of purposes and avoid possible risks of depletion and overexploitation, sustainable groundwater resource management is fundamental [2]. this overexploitation may harm the environment, particularly in dry and semi-arid areas vulnerable to water shortages [3].
Conventional approaches for groundwater research and mapping of Groundwater Potential Zones (GWPZs) are often expensive, time-consuming, and have a restricted scope [4]. These issues call for adaptable and cost-effective solutions. In this regard, thanks to the use of recent techniques, groundwater resource monitoring is now more efficient and affordable than before [5]. In other words, using multi-criteria decision analysis (MCDA) in conjunction with geospatial technologies like remote sensing, and GIS has shown to be a successful method for locating prospective groundwater zones around the globe. In fact, recent studies have shown the accuracy and reliability of these techniques in assessing potential groundwater sources. Actually, these methods can analyze numerous data and produce incredibly accurate findings, which makes them perfect tools for creating long-term groundwater management plans [4], [6]–[11].
Practically, researchers must first identify the most prominent factors that must be taken into account in order to establish a reliable Groundwater Potential Zone (GWPZ). In other words, the development of this model necessitates the selection of appropriate parameters, which involve linear density, geology/lithology, soil, drainage density, slope, land use/land cover (LULC), and precipitation. Generally, the features of the research field, the goals of the study, the availability of data, and other factors may influence the choice of parameters for Groundwater Potential Zone (GWPZ) models. Certain factors, however, such as lithology, lineament density, elevation, topographic wetness index (TWI), and geomorphology are given higher weight in other situations because of their significance in accurately forecasting probable groundwater sources [4]. Actually, once created, these models can provide more time and cost-effective options for groundwater research and mapping, as well as make groundwater resource management easier over the long run.
In the Guigou basin, there is now a higher need for irrigation water, especially during the dry season, as a result of the increasing cultivation of vegetable and cereal crops during the previous several decades, such as potatoes, onions, carrots, and grains. However, the lack of surface water and an ongoing series of dry years in the area have forced farmers in the Guigou River basin to dig wells to deal with the water shortage [12]. Indeed, an extensive study of the region's hydrogeological features is necessary for the long-term usage of its groundwater resources.
The main objective of the current study is to produce a map of areas of high groundwater potential by integrating GIS, remote sensing, and the Analytical Hierarchy Process (AHP) techniques, in order to identify optimal sites for the drilling of productive wells and to establish a comprehensive digital database that can help decision-makers design groundwater management strategies to address water shortages in the region.
To optimize writing in this manuscript, we're going to use abbreviations instead of long words (Tab, 1)
Table 1
Acronyms
|
Definition
|
GWPZ
GIS
MCDA
RS
LULC
AHP
CR
CI
OLI
DEM
USGS
ASTER
DWL
MBGL
|
Groundwater Potential Zones
Geographic Information System,
Multi-Criteria Decision Analysis,
Remote Sensing
land use/land cover
Analytical Hierarchy Process,
Consistency Ratio,
Consistency Index,
The Operational Land Imager,
Digital Elevation Model,
United States Geological Survey,
Advanced Spaceborne Thermal Emission and Reflection
Depth to Water Level
Meters below ground level
|
Study Area:
The Guigou Basin is situated upstream of the Upper Sebou Basin, covering an area that is equal to 14% of the former. With a southwest to northeast axis, the Sebou Basin spans a total of 1227 km2. In terms of latitude and longitude, this basin is situated between 33°15' and 33°27' north and 4°47' and 5°5' west. The Guigou Basin, which encompasses an intra-montane plain measuring around 175 km2, is also situated in the Central Middle Atlas. Around 1500 m is the basin's average elevation. In the southeast of the basin, the Folded Middle Atlas Mountains predominate, whereas in the northwest, the Tabular Middle Atlas Mountains predominate. (Fig. 1).
Different structural domains are covered by Guigou's geology. The investigations conducted [13], [14] demonstrate that the stratigraphic strata of the studied region span a significant time range, from the Triassic to the Quaternary. The Triassic is represented in the area by clay-salt facies and doleritic basalt facies that are interbedded in red argillites. The Jurassic lithology is characterized mainly by dolomitic limestone formations of the reef environment of the Lower Lias and marls of the Domerian. Moreover, a reef limestone formation from the upper Bajocian and greenish marly strata from the middle Bajocian make up the area's main stratigraphic cover.
According to Amrani (2016), the Quaternary period of the research region includes alluvium and residual basalt flow, both of which contain chunks of dolomite, flinty Liassic limestone, Eocene limestone, and Oligocene conglomerate.
Climatologically, the semi-arid environment of the study area is characterized by irregular rainfall patterns and protracted dry spells. At the Ait Khabache station, the annual precipitation is 350 mm, whereas at the Aguelmam Sidi Ali station, it is 405 mm (Fig. 2). There are also noticeable seasonal temperature variations, with summer highs of 38°C and winter lows of -4°C. El Hairchi et al. (2023) claim that this fluctuation causes the annual evaporation rates at the Ait Khabache and Aguelmam Sidi Ali stations to rise by 336 mm and 390 mm, respectively.
Hydrogeologically, the folded water tables and the tabular water tables of the Middle Atlas are two hydrogeological systems that meet at the Guigou basin. In fact, the geochemical compositions of these two systems are distinct, with the former having significant concentrations of sulfates and chlorides and the latter being less mineralized and comprising mostly calcium and magnesium [15]. Additionally, there is a discernible rise in the physicochemical characteristics and piezometric level of the water as it travels from Timahdit to Almis Guigou, pointing to the existence of a sizable recharge basin in this area.
Throughout the study area, the depth of the water's surface varies from less than 14 meters in areas near the fault to more than 20 meters in the center, and even more than 100 meters close to the Ahrouch fault (Fig. 3a). The subsurface flow is controlled by recent sub-meridional faults as well as transverse and longitudinal falls in the directions N20 to N45, N65 to N80, and N120 to N140 (Fig. 3b).