Effects of wastewater from peri-industrial site on soil physico-chemical properties in tropical environment

Abstract

Water scarcity and soil degradation are major environmental challenges which need immediate action for sustainable agriculture. At one side, urbanisation and industrialisation has dwindled freshwater resources and on the other hand generates a lot of wastewater which needs to be tackled. Under this situation, scientific management of wastewater can be resources for agriculture. To study the suitability of wastewater an incubation study was conducted to assess the impact of wastewater from a periindustrial area near the thermal power plant, Odisha at different wastewater dilution level of0, 25, 50, 75 and 100 percent with two methods of the application via cyclic and mixing on physicochemical properties of soil. Results indicated that with increased proportion of wastewater in soil, pH increased from 6.61 to 7.28 and electrical conductivity from 0.09 to 0.24 dS m-1. Similarly, cations viz. calcium, magnesium, ammoniacal-N, and sodium ions as well as anions nitrate-N and sulphate increased with increased wastewater proportion. Irrigation suitability in terms of sodium absorption ration (SAR), exchangeable sodium percentage (ESP) and magnesium hazards (MH) showed that 100% wastewater was suitable with respect to SAR and ESP but it had higher magnesium hazards compared to the permissible limit. Results showed that dilution level of 25% i.e. 75% freshwater and 25% wastewater showed better results in terms of suitability of water for irrigation without any harmful impact.