Groundwater fauna can be used as indicators of anthropogenic impacts on aquifers: A case study from Meknes area, Morocco

Abstract

The groundwater in the plain of Fez-Meknes constitutes a major resource in the region. The study highlights the importance of this resource, especially its irreplaceability. However, a number of inferences of point source pollution or diffuse were made. In this context, this study aimed at showing the possible relationships between the water quality of wells and springs and the diversity of the aquatic fauna which occurs in these habitats. To this end, the water quality and the fauna were regularly investigated in several stations (8 wells and 2 springs) selected in the region. The stations were chosen considering visible differences related to both their fauna and also some evident characteristics i.e. water table depth, nature of geological substratum, protection and human use, so that it was possible to expect certain diversity. The total faunal richness of stations was poorly correlated with water quality but, in contrast, the specific richness of the stygobiontic fauna (the subterranean species living in groundwater), and moreover the abundance of these stygobiontic species decreased significantly in case of water pollution. Thus the stygobiontic fauna and especially the peracarid crustaceans appear to be good indicators of water quality in the studied wells and springs.

Global overview on groundwater fauna

“…More detailed evaluation of the reviewed studies revealed that 70% of studies in Africa concentrated on the description of newly discovered groundwater fauna (Figure 7a). Nevertheless, more than a dozen of studies in Algeria and Morocco conducted eco‐toxicological investigations, revealing that faunal richness in some urban and mining areas is linked with groundwater quality and stygofauna abundance decreases with pollution (Aidaoui, 2019; Boughrous, 2007; Boughrous et al, 2007; Boulaassafer et al, 2021; Boulal et al, 2017; Boutin et al, 1995; Boutin & Idbennacer, 1989; El Adnani et al, 2006, 2007; el Moustaine et al, 2013, 2014; Hallam et al, 2008; Hichem et al, 2019; Laid & Zouheir, 2018; Merzoug et al, 2011, 2014; Ramzi et al, 2020) with authors proposing the use of stygofauna as bioindicators of water quality (Merzoug et al, 2011, 2014). Boulaassafer et al (2021) study on evolutionary processes considerably expanded the knowledge of diversity and geographic range of a freshwater snail genus, and information on endemism and biogeographical distribution of stygobiotic crustacean species of Africa and Madagascar has been recorded (Tuekam Kayo et al, 2012).…”