Typology and classification of water quality in an intermittent river in a semi-arid Mediterranean climate.

The typology and classification of rivers are highly relevant concepts in the field of limnology and freshwater ecology. Water body typology systematically categorizes water bodies based on their natural attributes, while water body classification groups them based on specific criteria or purposes for management, regulatory, or administrative reasons. Both concepts play important roles in understanding and managing water resources effectively. This scientific article focuses on the ZAT River in Morocco as a model for studying low-flow and intermittent rivers. The objective is to develop an accurate model for the typology and classification of small, low-flow rivers into homogeneous classes based on natural and anthropogenic factors. The study also investigates the impact of human activities on altering the uniformity and reference nature of the water body. The typology of water bodies is carried out according to the European methodology specified in The European Commission's Water Framework Directive (WFD) in 2000. The classification of water bodies is conducted by assessing their chemical and biological quality using the weighted index (WI), the Iberian Biological Monitoring Working Group (IBMWP) index, and multivariate statistical methods such as principal component analysis (PCA) for confirming water quality assessment. The results indicate the possibility of dividing the basin into four water bodies. Water bodies show homogeneity in terms of chemical quality when human influence is minimal or during periods of high river flow. However, increased human influence and decreased river flows lead to heterogeneity in chemical quality, indicating an unstable state. This study is the first of its kind in arid and semi-arid intermittent rivers, where such an approach could be suggested to determine their typology and classification.

Groundwater quality in Zagora southeast of Morocco by using physicochemical analysis and geospatial techniques.

Groundwater in Morocco is restricted because of the semiarid to arid climatic conditions; it is under threat from organic and inorganic pollution. Furthermore, it is considered the only source of potable water as well as having different usages, making its quantitative and qualitative protection an urgent priority. The present study focused mainly on the anthropogenic impact on the natural resources and groundwater quality around Zagora city. Fifteen samples were collected from wells during rainy and dry seasons in 2 years 2020-2021 and the analysis of the groundwater quality of studied stations. The suitability of the aquifer Fezouata was investigated using drinking and irrigation water quality indices. The results showed that sulfate and chloride are the dominant anions in the groundwater samples. While the mean abundance of major cations is Na + > Mg2+ > Ca2+ > K+, the sodium ion is dominant and K + is the least abundant. The physicochemical parameters show that conductivity, nitrate, and sulfate exceed the limit fixed by WHO. Hydrogeochemical plots indicate that 93% of samples belong to Na-Cl facies and only 7% are mixt Cl-Mg-Ca in 2021, the results are similar except for two samples which are 13% belong Cl-Mg-Ca. The Water Quality Index suggests that 28.55% are good quality water, 23.90-47.55% are poor and very poor quality water, respectively, and 40.24% are unsuitable in 2020. Furthermore, the WQI of the 2021 campaign showed that only 17.48% were considered good quality water and 38.94% (43.58%) were poor or very poor quality water, respectively. However, 33.21% are unsuitable. Based on irrigation indices, the majority of groundwater samples can be used for agricultural purposes, notably those of the upstream part of the study area.