Rainwater Quality Evaluation for Agricultural Use: Case Study of a Portland Cement Producing Area

Abstract

The quality and chemical composition of rainwater available for agricultural purposes are influenced by anthropogenic factors that have  a significant impact on crops and yields. This study was performed primarily to identify baseline rainwater quality conditions for irrigation  and other agricultural purposes. Rainwater from Ibeshe, home to two proximate Portland cement plants, was analysed for  anions, and cations and assessed for its agrarian usefulness. The physicochemical characteristics and total dissolved solids (TDS) (34.56  mg/L) measured in situ were suitable for agricultural purposes. Among the cations and macronutrients, Ca2+(434.47±212.67), Na⁺ (1768.9±724.8), K⁺ (594.3±296.0), Mg²⁺(521.33±62.43), and B³⁺(10.53±1.75) measured in meq/L exceeded the standards required for irrigation water, while all anions except nitrate, were within acceptable limits. The irrigation quality potentials of the rainwater samples  were assessed by determining parameters including sodium adsorption ratio (SAR), sodium hazard (SH), Kelly’s index (KI), soluble  sodium percentage (SSP), magnesium hazard (MH), potential salinity (PS), and calcium/magnesium ratio (Ca/Mg). Irrigation quality  indicators, including SAR (80.91 meq/L), KI (1.85 meq/L), SSP (71.2%), Ca/Mg (0.833) and MH (54.53 meq/L) showed the unsuitability of the  rainwater for irrigation purposes, while the PS (0.01 meq/L) and %Na (53.0%) values were within acceptable limits. The rainwater  quality will make the soil alkaline, saline, and clayish over time, and unsuitable for specific crops without prior soil amendment. The findings contribute to the understanding of rainfall chemistry in the cement-producing area of Yewaland by providing baseline  information for a previously unstudied community.