title: The effects and mode of action of biochar on the degradation of methyl isothiocyanate in soil.
abstract: Biochar is used as a new type of fertilizer in agriculture; however, its effect on the fate of fumigants in soil is not fully understood. The objective of this study was to investigate the effects of biochar on methyl isothiocyanate (MITC) degradation in soil in laboratory incubation experiments, including the effects of biochar composition, amendment rate, moisture, temperature, soil sterilization and soil type. The dissipation pathways of MITC in biochars included adsorption and chemical degradation. The adsorption of MITC by biochars was positively correlated with the specific surface area (SSA) of the biochar. Biochar with a high SSA and low H/C value (such as biochar type BC-1) reduced MITC degradation in soil substantially; following BC-1 amendment, the degradation rate was 73.9% slower than in unamended soil. The degradation of MITC was positively correlated with the H/C value of biochar, and MITC degradation in soil increased 2.2-31.1 times following amendment with biochars with higher H/C values (e.g. biochar types BC-3-6). The biochar with the lowest organic matter and low H/C value did not affect the fate of MITC in soil. Biochars affect abiotic degradation processes more than biodegradation. When soil samples had a higher water content (>10%), higher temperature (40°C), and lower organic matter, the addition of BC-1 biochar reduced MITC degradation substantially; and this did not change significantly when the amendment rate increased. However, BC-4 biochar accelerated MITC degradation with increasing amendment rate, increasing temperature, and decreasing soil water content. The differences in degradation rates due to soil type were minimized by amendment with BC-4, but significant differences in BC-1. The results showed that the rational use of biochar has the potential to reduce MITC emission by accelerated degradation and adsorption.
authors.affiliation: Plant Protection Institute of Chinese Academy of Agricultural Sciences, State key Laboratory for Biology of Plant Disease and Insect Pests, Beijing 100193, China.
authors.forename: Wensheng
authors.initials: W
authors.lastname: Fang
authors.affiliation: Plant Protection Institute of Chinese Academy of Agricultural Sciences, State key Laboratory for Biology of Plant Disease and Insect Pests, Beijing 100193, China. Electronic address: qxwang@ippcaas.cn.
authors.forename: Qiuxia
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Plant Protection Institute of Chinese Academy of Agricultural Sciences, State key Laboratory for Biology of Plant Disease and Insect Pests, Beijing 100193, China.
authors.forename: Dawei
authors.initials: D
authors.lastname: Han
authors.affiliation: Plant Protection Institute of Chinese Academy of Agricultural Sciences, State key Laboratory for Biology of Plant Disease and Insect Pests, Beijing 100193, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Liu
authors.affiliation: Plant Protection Institute of Chinese Academy of Agricultural Sciences, State key Laboratory for Biology of Plant Disease and Insect Pests, Beijing 100193, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Huang
authors.affiliation: Plant Protection Institute of Chinese Academy of Agricultural Sciences, State key Laboratory for Biology of Plant Disease and Insect Pests, Beijing 100193, China.
authors.forename: Dongdong
authors.initials: D
authors.lastname: Yan
authors.affiliation: Plant Protection Institute of Chinese Academy of Agricultural Sciences, State key Laboratory for Biology of Plant Disease and Insect Pests, Beijing 100193, China.
authors.forename: Canbin
authors.initials: C
authors.lastname: Ouyang
authors.affiliation: Plant Protection Institute of Chinese Academy of Agricultural Sciences, State key Laboratory for Biology of Plant Disease and Insect Pests, Beijing 100193, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Plant Protection Institute of Chinese Academy of Agricultural Sciences, State key Laboratory for Biology of Plant Disease and Insect Pests, Beijing 100193, China. Electronic address: caoac@vip.sina.com.
authors.forename: Aocheng
authors.initials: A
authors.lastname: Cao
mesh_terms: D002606:Charcoal / Q000737:chemistry*; D004784:Environmental Monitoring; D052918:Environmental Restoration and Remediation / Q000379:methods*; D017879:Isothiocyanates / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*
chemical_list: D017879:Isothiocyanates; D012987:Soil; D012989:Soil Pollutants; D002606:Charcoal
keywords: Abiotic degradation; Adsorption; Fertilizer; Fumigant; MITC