Suitability of treated wastewater with respect to pH, electrical conductivity, selected cations and sodium adsorption ratio for irrigation in a semi-arid region

Abstract

Increasing incidents of drought spells in most Sub-Saharan African countries call for exploration of innovative alternative sources of water for irrigation. A study was conducted to investigate the cation concentrations for different disposal points of treated wastewater and for borehole water. A 4 × 5 factorial experiment included a borehole as a reference sampling site plus three other sampling sites along the wastewater disposal system over 5 months. Monthly collected water samples were analysed for pH, EC, Ca, Mg, Na and K, with sodium adsorption ratio (SAR) computed and compared with those of water from the borehole, the FAO-desired ranges and the South African (SA) quality standards for irrigation water. Except at two sampling sites during one month, pH values were within the FAO-desired range. Relative to the FAO desired ranges and SA water quality standards, most variables in treated wastewater were much lower, suggesting that the test treated wastewater was suitable for irrigation.

Metagenomic assessment of nitrate-contaminated mine wastewaters and optimization of complete denitrification by indigenous enriched bacteria

“…Pt-SA, with sewage contamination, had higher anion concentrations as compared to the D-Lst sample with more water hardness containing elevated Mg 2+ , Ca 2+ , and CaCO 3 concentrations (Grochowska, 2020). According to the Department of Water Affairs and Forestry (DWAF) regulations in South Africa, the value of sodium adsorption ratio (SAR) above 1.5 in irrigation water is considered toxic for the environment and both samples' higher SAR values of 4.2 in Pt-SA and 2.41 in D-Lst indicate their toxicity, even for farming activities (DWAF, 1996;Kgopa et al, 2018).…”

Biochar from Date Palm Waste via Two-Step Pyrolysis: A Modified Approach for Cu (II) Removal from Aqueous Solutions

“…Water is an essential resource for the sustenance and development of agricultural and industrial applications, which are integral to human life [1][2][3]. The global concern over water scarcity is escalating, primarily due to droughts and contamination [4]. In the Kingdom of Saudi Arabia, a significant desert landscape and the risk of drought, stemming from low water availability and high agricultural and industrial water demands, are notable [5].…”

Chemical analysis of corn cob-based biochar and its role as water decontaminants

“…Water is very important sources for the continuity of life on earth [1]. Water scarcity worldwide due to droughts and contamination are concerns that intensify global worrying [2]. Globally with increasing population size there are increasing demands of water supply but the rapid rates of urbanization and industrialization resulted in the generation of polluted effluent waste [3].…”

“…When the levels of contaminants and pollution are rising, they are influenced both human and ecological system at the same time [4]. So looking for other sources for water is very important for the solution of water scarcity in different countries [2].…”