Key Laboratory 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, 315800, China; Zhejiang Provincial Key Laboratory of Subtropic Soil and Plant Nutrition, Zhejiang University, Hangzhou, 310058 China.
Key Laboratory 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, 315800, China; Department of Environmental Sciences, University of Peshawar, Peshawar 25120, Pakistan.
J Hazard Mater. 2018 Apr 15;348:100-108. doi: 10.1016/j.jhazmat.2018.01.031.
Biochar application has attracted great attention due to its diverse uses and benefits in the fields of environmental management and agriculture. Biochar modifies the composition of dissolved organic matter (DOM) in soil, which directly or indirectly controls the mobility of metal contaminants and their bioaccumulation. In this study, ten different hydrothermal biochars pyrolysed from mushroom waste (MSBC), soybean straw (SBBC), sewage sludge (SSBC), peanut shells (PNBC) and rice straw (RSBC) at two pyrolysis temperatures (200 °C and 350 °C) were used to investigate DOM changes in soil solution and their effects on metal availability and bioaccumulation. Biochar induced modification of soil DOM which was characterized by spectroscopic analysis of water soluble organic carbon, specific absorbance (SUVA), UV-vis absorption, spectral slope (S) and the absorption coefficient. Regarding rice plant growth, the biochar effects on biomass were greatly varied. Biochars (except for RSBC and MSBC) prepared at high temperature significantly (P ≤ 0.05) suppressed the availability of As and Cd in soil and their subsequent bioaccumulation in rice plants. The highest reduction (88%) in bioaccumulated As was observed in rice grown on soil amended with SBBC prepared at 350 °C (the highest temperature for hydrothermal technique). The addition of biochars (except RSBC and MSBC) prepared at high temperature markedly (p < 0.05) decreased AsIII (30-92%), while the effects on dimethylarsenic acid (DMA) and arsenate (AsV) concentrations were not significant except for SSBC350 (prepared at 350 °C) treatment. These results highlight the potential of biochar-DOM interactions as an important mechanism for suppressing the mobility and bioaccumulation of As and Cd in biochar-amended paddy agricultural systems.
生物炭的应用因其在环境管理和农业领域的多种用途和益处而受到广泛关注。生物炭会改变土壤中溶解有机物质（DOM）的组成，从而直接或间接地控制金属污染物的迁移及其生物累积。在这项研究中，使用了十种不同的水热生物炭，它们是由蘑菇废物（MSBC）、大豆秸秆（SBBC）、污水污泥（SSBC）、花生壳（PNBC）和稻草（RSBC）在两种热解温度（200°C 和 350°C）下热解而成的，以研究土壤溶液中 DOM 的变化及其对金属有效性和生物累积的影响。生物炭诱导了土壤 DOM 的变化，这是通过水溶性有机碳的光谱分析、特定吸光度（SUVA）、UV-vis 吸收、光谱斜率（S）和吸收系数来表征的。就水稻生长而言，生物炭对生物量的影响差异很大。高温下制备的生物炭（除了 RSBC 和 MSBC）显著（P≤0.05）抑制了土壤中砷和镉的有效性及其在水稻植株中的后续生物累积。在添加了由 350°C 高温下制备的 SBBC 处理的土壤中，水稻中累积的砷的减少量最大（88%）。高温下制备的生物炭（除了 RSBC 和 MSBC）的添加明显（p<0.05）降低了 AsIII（30-92%），而对二甲基砷酸（DMA）和砷酸盐（AsV）浓度的影响除 SSBC350（在 350°C 下制备）处理外，并不显著。这些结果强调了生物炭-DOM 相互作用作为抑制生物炭添加的稻田农业系统中砷和镉迁移和生物累积的重要机制的潜力。
