Restoration of pesticide contaminated agricultural soil through bio-augmentation and its kinetics

Abstract

Excessive use of pesticides is evident in third world countries and Pakistan is not the exception to this. Most of these pesticides are persistent and they remain present in ecosystem as active ingredient for longer duration. Their presence cause serious damage to micro flora and fauna, thus disturbing the functioning of ecosystems. After absorbance, they enter into food chain and tend to bio-accumulate. In the present situation, bio-augmentation and bio-stimulation are considered most safe techniques to clean pesticide contaminated soils. These techniques are natural, cost effective, do not produce toxic by products and easy to handle. The present study was designed to degrade chlorpyrifos (CP) in laboratory soil using Pseudomonas sp., which was isolated from industrial drain. This strain showed promising results in both liquid medium and soil. This strain degraded up to 60mg of CP per one Kg of soil. Among different organic amendments, farm yard manure was most effective and showed highly significant results. Kinetic analysis and its data also provide strong evidence of success. Kinetic parameters were as follow; R2 = 0.9917, Ks = 159.0271, Vmax = 9.64 and Vmax/Ks = 0.0606. This research is successful as it provided indigenous solution to a environmental problem.