Reduced bioavailability and plant uptake of polycyclic aromatic hydrocarbons from soil slurry amended with biochars pyrolyzed under various temperatures
- 191 Downloads
Biochar has high potential for organic pollutant immobilization due to its powerful sorption capacity. Nevertheless, potential risks may exist when biochar-sorbed organic pollutants are bioavailable. A direct plant exposure assay in combination with an organic solvent extraction experiment was carried out in this study to investigate the bioavailability of polycyclic aromatic hydrocarbons (PAHs) with the application of pine needle biochars pyrolyzed under different temperatures (100, 300, 400, and 700 °C; referred as P100–P700 accordingly). Biochar reduced solvent extractability and plant uptake of PAHs including naphthalene (Naph), acenaphthene (Acen), phenanthrene (Phen), and pyrene (Pyr), especially for three- and four-ring PAHs (Phen and Pyr) with high-temperature biochar. Plant uptake assay validates with organic solvent extraction for bioavailability assessment. Sorption of PAHs to biochars reduced plant uptake of PAHs in roots and shoots by lowering freely dissolved PAHs. Aging process reduced the bioavailability of PAHs that were bound to biochar. High pyrolysis temperature can be recommended for biochar preparation for purpose of effectively immobilizing PAHs, whereas application of moderate-temperature biochar for PAH immobilization should concern the potential risks of desorption and bioavailability of PAHs.
KeywordsBiochar Polycyclic aromatic hydrocarbons Bioavailability Plant uptake Aging Pyrolysis temperature
This project was supported by the National Natural Science Foundation of China (Grant nos. 21425730, 21537005, 21621005, and 21607125), the National Basic Research Program of China (Grant no. 2014CB441106), and the Postdoctoral Science Foundation of China (Grant no. 2015M581943).
- Cornelissen G, Gustafsson O, Bucheli TD, Jonker MTO, Koelmans AA, Van Noort PCM (2005) Extensive sorption of organic compounds to black carbon, coal, and kerogen in sediments and soils: mechanisms and consequences for distribution, bioaccumulation, and biodegradation. Environ Sci Technol 39:6881–6895CrossRefGoogle Scholar
- Hauck M, Huijbregts MAJ, Koelmans AA, Moermond CTA, van den Heuvel-Greve MJ, Veltman K, Hendriks AJ, Vethaak AD (2007) Including sorption to black carbon in modeling bioaccumulation of polycyclic aromatic hydrocarbons: uncertainty analysis and comparison to field data. Environ Sci Technol 41:2738–2744CrossRefGoogle Scholar
- Ren X, Sun H, Wang F, Cao F (2016) The changes in biochar properties and sorption capacities after being cultured with wheat for 3 months. Chemosphere 144:2257–2263Google Scholar
- Sun D, Meng J, Chen W (2013a) Effects of abiotic components induced by biochar on microbial communities. Acta Agricul Scandinavica B 63:633–641Google Scholar
- Wang C, Zou X, Zhao Y, Li B, Song Q, Li Y, Yu W (2016) Distribution, sources, and ecological risk assessment of polycyclic aromatic hydrocarbons in the water and suspended sediments from the middle and lower reaches of the Yangtze River, China. Environ Sci Pollut Res 23:17158–17170CrossRefGoogle Scholar