Biochars Reduce Mine Land Soil Bioavailable Metals. Issue 2 (1st March 2017)

• Record Type: Journal Article
• Authors: Ippolito, J. A.; Berry, C. M.; Strawn, D. G.; Novak, J. M.; Levine, J.; Harley, A.
• Is Part Of: Journal of Environmental Quality. Volume 46:Issue 2(2017)
• Page Start: 411
• Page End: 419
• Publication Date: 2017-03-01
• Subjects: Agricultural ecology -- Periodicals; Environmental engineering -- Periodicals; Pollution -- Periodicals; 630
• DOI: 10.2134/jeq2016.10.0388
• Languages: English
• ISSNs: 0047-2425

Abstract

Abstract : Biochar has been proposed as an amendment to remediate mine land soils; however, it could be advantageous and novel if feedstocks local to mine land sites were used for biochar production. Two different feedstocks (pine beetle–killed lodgepole pine [ Pinus contorta ] and tamarisk [ Tamarix spp.]), within close proximity to mine land–affected soils, were used to create biochars to determine if they have the potential to reduce metal bioavailability. Four different mine land soils, contaminated with various amounts of Cd, Cu, Pb, and Zn, received increasing amounts of biochar (0, 5, 10, and 15% by wt). Soil pH and metal bioavailability were determined, and the European Community Bureau of Reference (BCR) sequential extraction procedure was used to identify pools responsible for potential shifts in bioavailability. Increasing biochar application rates caused increases in soil pH (initial, 3.97; final, 7.49) and 55 to 100% (i.e., no longer detectable) decreases in metal bioavailability. The BCR procedure supported the association of Cd with carbonates, Cu and Zn with oxyhydroxides and carbonates, and Pb with oxyhydroxides; these phases were likely responsible for the reduction in heavy metal bioavailability. This study proved that both of these feedstocks local to abandoned mining operations could be used to create biochars and reduce heavy metal bioavailability in mine land soils. Core Ideas: Local feedstocks were used to create biochars used for local mine land reclamation. Novel creation and use of biochar were used to solve a localized issue. Biochar application caused bioavailable Cd, Cu, Zn, Pb reduction. Metal carbonate and oxyhydroxide precipitates formed after biochar application.