In recent decades, water pollution has become a major concern, threatening both humans and natural ecosystems. This study aims to analyze seasonal variations in the quality of surface water of the Nador Canal in Morocco, using the water quality index (WQI) and principal component analysis (PCA). Surface water samples from 22 sites along the canal were analyzed for physical, chemical, and heavy metal parameters. The results of the study revealed significant seasonal variations, with water quality decreasing in the summer months, while its quality generally improved in winter. The predominant water type was Na⁺-Cl⁻ in summer, while it was the mixed Ca²⁺-Na⁺-HCO₃⁻ water type in winter. WQI values also varied seasonally, with an average of 113.04 in summer and 160.6 in winter, classifying the water as unsuitable for drinking but suitable for irrigation throughout the year. The results of the water quality index are consistent with the results of the principal component analysis of surface water in the Nador Canal, where the results of the principal component analysis showed that there are significant seasonal variations in water quality. In both summer and winter, major ions like magnesium, sodium, and calcium predominantly indicate influences from natural and anthropogenic sources. In winter, heavy metals and nutrients, signaling pollution from industrial and agricultural runoff, become especially prominent. These variations are influenced by rainfall patterns and agricultural runoff, emphasizing the need for adaptive water management practices to maintain crop and soil health. This study provides new insights into the dynamic interplay between seasonal factors and water quality, offering valuable guidance for local water resource management.

In recent decades, water pollution has emerged as a significant concern, posing a threat to both humans and natural ecosystems. This study aimed to assess the spatial variations in water quality in the Nador Canal, Morocco using the water quality index combined with multivariate statistical techniques and geographic information systems (GIS). The parameters examined were then compared to the maximum permissible limit values recommended by Moroccan surface water standards and the World Health Organization. The results indicated that the WQI of Nador Canal is generally suitable for irrigation and unsuitable for drinking. It indicated that the quality of surface water in the Nador Canal is affected by organic pollutants, and this is evidenced by low levels of dissolved oxygen, the levels of elements were high, especially chlorine and sodium, in addition to a high concentration of ammonia, nitrate, and phosphate in some of the stations studied. Principal component analysis (PCA) results revealed that PC1–PC3 collectively accounted for 73% of the variation in surface water quality within the study area. The cluster analysis also proves that the water quality is relatively polluted. Potential contributing factors to surface water pollution include changes in the hydrological regime, household waste discharges, and agricultural activities. These findings furnish essential insights into water quality, particularly its suitability for irrigation, and contribute to enhancing the water quality management system of the Nador Canal in the Gharb region of Morocco.

The urban Oringa River basin is facing rapid degradation due to population growth and land use changes. The integration of remote sensing, GIS, and the Revised Universal Soil Loss Equation (RUSLE) provides an effective approach to monitor and to evaluate soil erosion in this region. The study...

Surface water quality is a crucial determinant of environmental and public health, particularly in arid and semi-arid regions such as northwestern Morocco, where waterways like the Drader Valley support agriculture, ecosystems, and local communities. This study assessed seasonal variations in nitrate contamination and associated human health risks in surface water from three sampling sites (S1–S3) along the Drader River. Nitrate concentrations varied strongly by season, peaking during the dry season and exceeding permissible limits at S2 and S3. Health risk assessment using the Target Hazard Quotient (THQ) revealed values above the safety threshold (THQ > 1) at S2 and S3, indicating potential non-carcinogenic risks for local residents. Children were identified as the most vulnerable group, with higher THQ values than adults across all sites and seasons. These findings highlight the urgent need for enhanced water quality monitoring, stricter pollution control measures, and targeted protection of vulnerable populations. The results provide a scientific basis for sustainable water resource management in the Drader Valley and comparable arid and semi-arid regions.