Role of woody biochar and fungal-bacterial co-inoculation on enzyme activity and metal immobilization in serpentine soil
- 987 Downloads
In 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 methods
A 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 discussion
An 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.
Results 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.
KeywordsBiochar Bioremediation Black carbon Charcoal Phytotoxicity
Biochar production and characterization of this research was supported by the Basic Science Research Program, through the National Research Foundation of Korea (NRF), funded by the Ministry of Education, Science and Technology (project number: 2012R1A1B3001409) (100 %).
- Neilson S, Rajakaruna N (2015) Phytoremediation of agricultural soils: using plants to clean metal-contaminated arable land. In: Phytoremediation, Springer, 159–168Google Scholar
- Rajakaruna N, Tompkins KM, Pavicevic PG (2006) Phytoremediation: an affordable green technology for the clean-up of metal-contaminated sites in Sri Lanka. Ceylon J Sci 35:25–39Google Scholar
- Rajapaksha A, Ahmad M, Vithanage M, Kim K-R, Chang J, Lee S, Ok Y (2015) The role of biochar, natural iron oxides, and nanomaterials as soil amendments for immobilizing metals in shooting range soil. Environ Geochem Hlth 1–12Google Scholar
- Smith SE, Read DJ (1996) Mycorrhizal symbiosis. Academic pressGoogle Scholar
- Tabatabai MA (1994) Soil enzymes. In: Bottomley PS, Angle JS, Weaver RW (eds) Methods of soil analysis: part 2—microbiological and biochemical properties. Soil Science Society of America, Madison, pp 775–833Google Scholar