| Institution: | 1.Chemical and Environmental Systems Modeling Research Group,National Institute of Fundamental Studies,Kandy,Sri Lanka;2.Microbial Biotechnology Unit,National Institute of Fundamental Studies,Kandy,Sri Lanka;3.College of the Atlantic,Bar Harbor,USA;4.Unit for Environmental Sciences and Management,North-West University,Potchefstroom,South Africa;5.Korea Biochar Research Center and Department of Biological Environment,Kangwon National University,Chuncheon,Korea |
| Abstract: | PurposeIn this study, we investigated the effect of biochar (BC) and fungal bacterial co-inoculation (FB) on soil enzymatic activity and immobilization of heavy metals in serpentine soil in Sri Lanka.Materials and methodsA pot experiment was conducted with tomatoes (Lycopersicon esculentum L.) at 1, 2.5, and 5 % (w/w) BC ratios. Polyphenol oxidase, catalase and dehydrogenase activities were determined by idometric, potassium permanganate oxidisable, and spectrophotometric methods, respectively. Heavy metal concentrations were assessed by 0.01 M CaCl2 and sequential extraction methods.Results and discussionAn increase in BC application reduced polyphenol oxidase, dehydrogenase, and catalase activity. The application of FB increased soil dehydrogenase activity, with the maximum activity found in 1 % BC700?+?FB treatment. Moreover, the CaCl2 extractable metals (Ni, Mn, and Cr) in 5 % BC700 amended soil decreased by 92, 94, and 100 %, respectively, compared to the control. Sequential extraction showed that the exchangeable concentrations of Ni, Mn, and Cr decreased by 55, 70, and 80 % in 5 % BC700, respectively.ConclusionsResults suggest that the addition of BC to serpentine soil immobilizes heavy metals and decreases soil enzymatic activities. The addition of FB to serpentine soil improves plant growth by mitigating heavy metal toxicity and enhancing soil enzymatic activities. |
