title: The influence of various biochars on the bioaccessibility and bioaccumulation of PAHs and potentially toxic elements to turnips (Brassica rapa L.).
abstract: The influence of amending a contaminated soil with different dry-pyrolyzed biochars on the bioaccessibility and biouptake of polycyclic aromatic hydrocarbons (PAH) and potentially toxic elements (PTE) in turnip (Brassica rapa L.,) was investigated. This is the first study to examine the influence of biochar amendments on turnips grown in a contaminated soil. The biochars came from different local feedstocks, including sewage sludge biochar (SSBC), soybean straw biochar (SBBC), rice straw biochar (RSBC) and peanut shell biochar (PNBC). The biochars were applied to soil at 2% and 5% amendments, and the resulting influence on various soil and porewater properties were quantified. The bioaccessible concentrations of PAHs in soil and their bioaccumulation in B. rapa L. significantly (P < 0.05) decreased in the biochar amended soils. Biochar additions significantly (P ≤ 0.05) reduced the bioaccumulation of PTEs (As, Cd, Cu, Pb and Zn) in B. rapa L, though not as much as for PAHs. The most effective biochar at reducing both PAHs and PTEs was PNBC (P ≤ 0.05). Amendments of 5% biochar were more effective at reducing contaminant bioaccessibility than amendments at 2% (P < 0.05). Crop yield, however, increased the most for the 2% biochar amendments, in particular for SSBC (with a 49% increase in crop yield compared to the non-amended soil). Therefore, which biochar would be the most advantageous in this system would require a cost-benefit analysis between increasing crop yield (best achieved with 2% SSBC amendments) and decreasing the PAH and PTE uptake (best achieved with 5% PNBC amendments).
authors.affiliation: Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Department of Environmental Science, University of Peshawar, Peshawar 25120, Pakistan. Electronic address: sardar.khan2008@yahoo.com.
authors.forename: Sardar
authors.initials: S
authors.lastname: Khan
authors.affiliation: Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Department of Environmental Science, University of Peshawar, Peshawar 25120, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Waqas
authors.affiliation: College of Ecology, Lishui University, Lishui 323000, China.
authors.forename: Fenghua
authors.initials: F
authors.lastname: Ding
authors.affiliation: Department of Environmental Science, University of Peshawar, Peshawar 25120, Pakistan.
authors.forename: Isha
authors.initials: I
authors.lastname: Shamshad
authors.affiliation: Department of Environmental Engineering, Norwegian Geotechnical Institute, Ullevaal Stadion, Oslo NO-0806, Norway.
authors.forename: Hans Peter H
authors.initials: HPH
authors.lastname: Arp
authors.affiliation: Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Ningbo Urban Environment Observation and Research Station, Chinese Academy of Sciences, Ningbo 315830, China. Electronic address: gli@iue.ac.cn.
authors.forename: Gang
authors.initials: G
authors.lastname: Li
mesh_terms: D010367:Arachis; D001151:Arsenic / Q000378:metabolism*; D029688:Brassica napus / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D002606:Charcoal / Q000494:pharmacology*; D019216:Metals, Heavy / Q000378:metabolism*; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism*; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D019216:Metals, Heavy; D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants; C540010:biochar; D002606:Charcoal; D001151:Arsenic
keywords: Bioaccumulation; Biochars; Polycyclic aromatic hydrocarbons; Potentially toxic elements; Turnip