APPLICABILITY OF SPENT MUSHROOM COMPOST (SMC) AS ORGANIC AMENDMENT FOR REMEDIATION OF POLLUTED SOILS

Abstract

In this paper we studied the remediation of two soils by applying spent mushroom compost (SMC) in three doses: 0, 40,000 and 80,000 kg ha -1 . The major pollutants considered were Cd, Pb and Cu. Triplex halimus was used as a plant indicator of the level of soil contamination. It was established that the addition of SMC affected the uptake of heavy metals in Atriplex halimus. There is a significant decrease in the concentration of heavy metals in shoots with increased dose of SMC. In the most polluted soil, the increase of SMC from 0 to 80,000 kg ha -1 caused a decrease in Pb in shoots from 48.62 to 11.32 mg kg -1 . Similarly Cd decreased from 8.66 to 4.44 mg kg -1 and Cu of 86.4 to 45.4 mg kg -1 . Results obtained after three months of plantation demonstrates that the SMC amendments produce a higher shoot and root growth in comparison with the control treatment. This is possibly due to an improvement in the physical properties of soils, a significant increase in available nutrients and an immobilization of heavy metals that otherwise produce toxic effects. That means that SMC can be a good organic amendment for soils used for sustainable plant production.