Potential variations in groundwater quality for household and irrigation applications as affected by climate change

Abstract

Groundwater quality is being deteriorated as a result of climate change, overuse, and decreased precipitation, consequently impacting both agricultural productivity and human health. Thus, to investigate the potential variations in groundwater quality for irrigation and household applications, groundwater samples were collected from 88 different sites in Sarat Al-Baha region, Saudi Arabia. The Al-Baha region is characterized by a fragile agro-ecosystem, which is extremely susceptible to climate change. The collected samples were subjected to hydrochemical analyses to determine whether groundwater was suitable for irrigation and household consumption. Results showed that concentrations of nitrate and heavy metals were within maximum permissible limits for drinking purposes in 91% of the collected samples. However, because of elevated levels of arsenic and nitrate, 8% of the collected groundwater samples were deemed to be of poor or very poor quality for drinking purposes. The estimated saturation index revealed that the majority of the minerals in the samples were under-saturated, suggesting a higher possiblity of salinity owing to the dissolution of under-saturated minerals, conseqently increasing iron, calcium, magnesium, sodium, chloride, and sulfate concentrations. No sodicity risks were anticipated, despite of medium to higher salinity hazard. More than 90% of the collected groundwater samples had unsatisfactory quality for irrigation purposes due to the presence of salts in higher amounts, which could be due to lower precipitation and higher temperature in the study area. Hence, employing suitable management strategies to maximize groundwater utilization is recommended to avoid further groundwater quality deterioration. Groundwater discharge must be ristricted, cropping patterns should be altered to boost water productivity, and grounwater quality must be monitored on regular basis.