Assessing Groundwater Quality and its Impact on Agricultural Productivity in Morocco

Abstract

This study investigates the relationship between groundwater quality and agricultural productivity across six experimental stations in Morocco: Doukkala, Bahira, Tassaout, Beni Amir, Beni Moussa and Tadla. To assess groundwater suitability for irrigation, a comprehensive suite of indices was employed, including the permeability index (PI), Kelly index (KI), sodium strength percentage (SSP), sodium adsorption ratio (SAR), residual sodium carbonate (RSBC), magnesium hazard (MH), Langelier saturation index (LSI), Ryznar stability index (RSI), aggression index (AI), Larson and Skold index (LS), and Puckorious saturation index (PSI). Results indicated significant variations among the stations. Doukkala showed moderate permeability and low salinity risk but high sodium levels (SSP 50.14, SAR 6.87). Bahira had similar trends with slightly higher PI and KI values. Tassaout demonstrated lower values across all indices, suggesting better groundwater quality. Beni Amir and Beni Moussa exhibited decreasing trends in indices, with Beni Moussa having the lowest values overall. Notably, Beni Amir had the most negative RSBC value, indicating a high sodium hazard and potential soil structure issues, while Tadla had the least negative RSBC value, indicating favorable conditions. Water in Beni Amir and Beni Moussa, with MH values of 56.37 and 56.84 respectively, was deemed unsuitable for irrigation, whereas Doukkala, Bahira, Tassaout, and Tadla, with MH values below 50, were considered suitable. The study concludes that groundwater quality varies significantly across regions, impacting agricultural productivity, with some regions posing higher risks due to sodium and magnesium hazards.

Keywords

• groundwater quality
• agricultural productivity
• irrigation suitability
• water quality indices
• sustainable water management