生物炭是由生物质在完全或部分缺氧的情况下经热解炭化产生的一类高度芳香化难熔性固态物质，具有改善土壤理化性质、调控营养元素循环、防治重金属、多环芳烃等污染物迁移转化等功能，因此，在土壤改良与修复领域具有较好的应用前景。但是，生物炭的施用将对土壤中的微生物群落结构组成带来影响，从而改变整个生态系统的物质循环过程。本文综述了近年来国内外有关生物炭对土壤微生物分布影响的研究进展，探讨了生物炭对土壤微生物生长代谢的作用机制，阐述了生物炭对于微生物主导的土壤生物地球化学过程产生的影响作用。相关研究发现，土壤总微生物生物量在生物炭施用后或增加，或不变，或呈现下降趋势；不同种类微生物对于生物炭的响应非常复杂，从而呈现出各异的土壤微生物群落结构组成。生物炭对微生物生长代谢的影响源于改变pH环境、影响水分分布、调节养分循环等多种机制的协同作用，而生物炭在对环境物质的吸附以及对微生物的直接吸附方面扮演着重要角色。同时，生物炭对于土壤微生物群落结构组成的影响还会随着时间的推移而发生变化。生物炭对土壤中微生物分布的改变还会进一步影响微生物的生物地球化学功能，对温室气体排放、碳氮循环和有机污染物降解等生物地球化学过程产生重要影响。因此，有待开展更多关于生物炭对于土壤微生物分布及其生态功能的影响的深入研究，以期更全面地评价生物炭对土壤环境质量的影响作用，为生物炭的实际应用提供依据。%Biochar, a solid material containing high fractions of aromatic functional groups, is produced through thermal degradation of biomass in the absence of oxygen or with limited oxygen. Biochar amendment can improve the physio-chemical properties of soils, regulate cycling of nutrient elements, and control transfer of pollutants, including heavy metals and poly-aromatic hydrocarbons. Although biochar can be potentially used for soil amendment, it influences the microflora in the soil environment, leading to changes in element cycling within the ecosystem. This paper summarizes recent advances about the effect of biochar on the distribution of soil microorganisms, discusses the mechanisms of biochar on the growth and metabolism of microbes, and illustrates the influence of biochar on the biogeochemical processes regulated by soil microorganisms. Previous studies demonstrated that the total biomass of soil microbes may increase, remain constant, or even decrease after biochar application to the soil environment. Different microorganisms show complex responses to biochar amendment, resulting in formation of unique microbial community structures in different soils. The influence of biochar on the growth and metabolism of microorganisms originated from the interrelated effects of several mechanisms, including pH changes, water distribution, and manipulation of nutrient cycling. In these mechanisms, adsorption of inorganic/organic compounds and microbial thallus by biochar play important roles. The effect of biochar on microbial community structure changes over time. Biochar also influences the eco-functions of microorganisms, resulting in changes in biogeochemical processes, such as emission of greenhouse gas, cycling of carbon and nitrogen, and degradation of organic pollutants. Further studies must be conducted to elucidate the effect of biochar on soil quality and provide useful information for biochar applicationin soil amendment.
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