Effect of Long-term Application of Sewage Water on Soil Properties of Different District of Haryana in Indo-Gangetic Plain

Abstract

The use of sewage water for irrigation has been shown to improve the chemical properties and fertility status of soils. Sewage water provides essential nutrients for plant growth; however, it also contains heavy metals that may become toxic to health if their concentrations exceed permissible limits. To monitor this situation, a survey was conducted to assess the long-term impacts of sewage water irrigation on soil nutrient status and heavy metal concentrations. Soil samples were collected from fields irrigated with sewage water and non-sewage water at various sites in Karnal, Panipat and Hisar districts of Haryana, where these water sources are directly used for crop irrigation. Samples were taken from three soil depths (0–15, 15–30 and 30–45 cm) to assess changes in soil chemical properties due to sewage irrigation. Samples from nearby fields irrigated with non-sewage water served as controls. The highest soil EC (0.83 dSm-1) was observed in soil irrigated with sewage water in Hisar district after the harvest of pearl millet, whereas the highest pH and OC values, 8.39 and 0.85%, respectively, were recorded in soil from Karnal district after the harvest of wheat. The highest CaCO3 content (0.96%) was observed in soils irrigated with sewage water in Hisar after the wheat crop. Nitrogen (182 kg/ha) and phosphorus (26.14 kg/ha) contents were highest in soils irrigated with sewage water in Karnal during the wheat crop, whereas potassium (321 kg/ha) was highest in Panipat soils during the rice crop. The maximum cation exchange capacity (CEC) (19.95 cmol(p+)/kg) was observed in soils irrigated with sewage water. Exchangeable cations, Ca² (6.10 cmol(p+)/kg), Mg² (9.30 cmol(p+)/kg), Na (3.70 cmol(p+)/kg) and K (1.32 cmol(p+)/kg), were also higher in soils irrigated with sewage water. Exchangeable CO ² ions were not detected in the surface soil but were present in the subsurface layers of sewage-water-irrigated soil, irrespective of location and crop. Among the exchangeable anions, HCO (2.85 cmol(p+)/kg), Cl (3.28 cmol(p+)/kg) and SO ² (1.92 cmol(p+)/kg) reached their maximum values in sewage-irrigated soils.