Biochar has a strong ability to sorb various pollutants due to its unique surface properties, morphological characteristics and abundant, discretely-distributed pores, implying a great potential for use in soil pollution control and remediation. Following field application of biochar to soil, various ageing processes may occur due to the decomposition and leaching of biochar's labile components and the interactions between biochar, soil and microbes, leading to significant changes in biochar's chemical and physical properties over time. These mixed, complicated changes can be classified into: chemical changes (e.g., loss of inorganic elements, changes of surface functional groups, partial mineralization of unstable components) and physical changes (e.g., changes of pore system resulting from surface coating by soil-origin organic matter and minerals). Biochar's ageing may lead to changes in characteristics of sorption and desorption of organic pollutant in soil, which are highly dependent on properties of soil, biochar and organic pollutant. In this paper, the mechanisms and influential factors of biochar ageing in agricultural soil as well as its effects on the sorption and desorption of organic pollutants are reviewed, and the focuses of future study are also proposed.%生物质炭独特的表面性质、形貌结构及丰富而离散的孔隙系统使其对有机污染物具有良好的持留与吸附作用,可望用于土壤污染控制与修复.在田间条件下,进入土壤的生物质炭自身不稳定组分会发生转化、淋溶,并与土壤发生相互作用出现老化现象,导致生物质炭的化学与物理性质发生显著变化.生物质炭在土壤中的老化过程具有复杂性和多样性,主要包括:生物质炭化学性质的变化,如无机元素的流失、表面官能团组成的变化以及部分矿化反应;生物质炭物理性质的改变,主要是土壤有机质和矿物质对生物质炭的包覆作用造成生物质炭的孔隙特征发生改变.生物质炭在土壤中的老化可能会导致有机污染物的吸附-解吸行为发生改变,且受土壤、生物质炭以及污染物性质的影响较大.本文综述了生物质炭在农田土壤中的老化机理及主要影响因素研究方面的进展,总结了生物质炭在土壤中的老化对有机污染物吸附-解吸行为的影响,提出了尚待解决的相关前沿科学问题.
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