EFFECTS OF HEAVY METALS (Cd, Zn and Cu) ON CARBON, NITROGEN AND IRON MINERALIZATION IN SOIL
Journal: Malaysian Journal of Sustainable Agriculture (MJSA)
Author: Falguni Akter, Humaira Hasan Tinni, Parmita Banarjee, Mohammad Zaber Hossain
This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
A sixty days laboratory incubation study was conducted to investigate the effect of heavy metals on soil carbon, nitrogen and iron mineralization under aerobic condition. Sulphate salts of cadmium, zinc and copper were added individually and in combinations to soil samples and incubated in different plastic pots. Soil organic carbon did not change significantly throughout the incubation period. Soil microbial biomass carbon declined from 0.38mgkg-1to 0.19 mgkg-1 in Cd treated soil and 0.39 mgkg-1 to 0.28 mgkg-1 in Cu treated soil which account for about 50% and 28% reduction (p ≤0.05) in biomass carbon respectively. Cd:Zn and Cu:Cd treated soil had reduced 36.84% while Zn:Cu had 42.11% reduction in biomass carbon.CO2-C effluxes peaked by day 15 for all the single metal amended soil indicating that priming effects might have occurred. But in combination, metal showed some interaction for what the respiration rates were declined for the first 15 days. Rapid ammonification with presumed immobilization to ok place up to day 30. The result indicated a significant (p ≤0.05) net mineralization of nitrogen for Cd:Zn (63.72%) and Cu:Cd (66.66%) treatments at the end of the experiment. Available iron content showed significant changes in combined metal treatment than a single metal.