The physical and chemical properties of control soil, soil treated with 75% silk dyeing effluent, and biotreated effluent soil were evaluated in a pot study under freshwater conditions. The biofertilizer Pseudomonas fluorescens was applied by mixing it with crude effluent and allowing biological treatment. Physical parameters such as pH and electrical conductivity (EC) of the biotreated soil were within standard limits, similar to the control soil. Soil texture remained consistent throughout the study.
The results also demonstrated that biotreatment enhanced the micronutrient content of the soil, keeping it within the optimal range. The biofertilizer significantly improved levels of macronutrients: Calcium, Nitrogen, Phosphorus, and Potassium increased from 105, 76, 4, and 137 ppm in effluent-treated soil to 110, 200, 14.5, and 390 ppm, respectively, in biotreated effluent soil. Similarly, micronutrients such as Iron, Manganese, Copper, and Zinc increased from 1.2, 10, 0.4, and 0.2 ppm in effluent-treated soil to 6.1, 26.22, 2.26, and 2.13 ppm, respectively, in biotreated soil.
These findings indicate that the adverse impact of effluent on soil nutrients was effectively mitigated by the biofertilizer. Overall, biotreatment enhanced both macro- and micronutrient levels in effluent-contaminated soil, providing a cost-effective and eco-friendly approach to sustaining the productivity of green leafy vegetable crops.