The results have indicated that application of sewage water for irrigation led to a significant difference in pH and EC of soil. The concentrations of K, Na and Cl did not show any significant difference in all the sewage irrigation sites. But there are significant differences on mean values in the concentrations of Ca, Mg, and SO4 for sewage applied sites. There was significant increase in the total nitrogen in the soil for sewage water (SW) and treated sewage water (TSW) applied sites as compared to the groundwater (GW) irrigation site. Effect of irrigation with different qualities of sewage on the concentration of heavy metals. It is apparent that the concentrations of heavy metals in soils with different kinds of irrigation water were lower in background values and non-significant; all the other heavy metals exhibit values below background concentrations for heavy metals in soils taken from FAO. The heavy metal concentrations (SW) applied site was, however, below the safe limits of Indian (Awashthi, 2000) and EU standard (European Union, 2002). The results of statistical analysis of total N, total P, Ca, K, Na, and Zn mg/kg−1 in tomatoes crop were significantly higher than the groundwater treated plants.
Alghobar, M. A., & Suresha, S. (2017). Evaluation of metal accumulation in soil and tomatoes irrigated with sewage water from Mysore city, Karnataka, India. Journal of the Saudi Society of Agricultural Sciences, 16(1), 49–59. https://doi.org/10.1016/j.jssas.2015.02.002