Abstract：
As a widespread pollutant in the environment, research on microplastics have attracted much attention. This review systematically analyzed the interaction between microplastics and soil microorganisms based on existing literatures. Microplastics can change the structure and diversity of soil microbial communities directly or indirectly. The magnitude of these effects depends on the type, dose and shape of microplastics. Meanwhile, soil microorganisms can adapt to the changes caused by microplastics through forming surface biofilm and selecting population. This review also summarized the biodegradation mechanism of microplastics, and explored the factors affecting this process. Microorganisms will firstly colonize the surface of microplastics, and then secrete a variety of extracellular enzymes to function at specific sites, converting polymers into lower polymers or monomers. Finally, the depolymerized small molecules enter the cell for further catabolism. The factors affecting this degradation process are not only the physical and chemical properties of the microplastics, such as molecular weight, density and crystallinity, but also some biological and abiotic factors that affect the growth and metabolism of related microorganisms and the enzymatic activities. Future studies should focus on the connection with the actual environment, and develop new technologies of microplastics biodegradation to solve the problem of microplastic pollution.
摘要：
作为环境中广泛存在的污染物，微塑料的研究备受关注。本文在已有文献的基础上,系统分析了微塑料与土壤微生物的相互作用。微塑料可以直接或间接改变土壤微生物群落的结构和多样性。这些影响的大小取决于类型，微塑料的剂量和形状。同时,土壤微生物可以通过形成表面生物膜和选择种群来适应微塑料引起的变化。综述了微塑料的生物降解机理,并探讨了影响这一过程的因素。微生物首先会在微塑料表面定居，然后分泌各种胞外酶在特定部位起作用，将聚合物转化为低级聚合物或单体。最后,解聚的小分子进入细胞进一步分解代谢。影响这种降解过程的因素不仅是微塑料的物理和化学性质，如分子量，密度和结晶度，但也有一些影响相关微生物生长代谢和酶活性的生物和非生物因素。未来的研究应侧重于与实际环境的联系，开发微塑料生物降解新技术，解决微塑料污染问题。
