Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, School of Environmental Science and Engineering, Hainan University, Haikou 570228, China.
Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province, School of Environmental Science and Engineering, Hainan University, Haikou 570228, China; Key Laboratory of Environmental Toxicology, Hainan University, Haikou 570228, China.
J Hazard Mater. 2024 Dec 5;480:135763. doi: 10.1016/j.jhazmat.2024.135763. Epub 2024 Sep 5.
The effects of endogenous mangrove litterfall (MF) inputs on organic matter transformation in sediment polluted by exogenous microplastics (MPs) were investigated in this work, and their linkage with microbial characteristics was also explored. MF inputs significantly affected organic carbon transformation in MPs-polluted sediment by improving humification, enzymatic activities and carbon utilisation capacity of microbes. Such effects were mainly linked with the enrichment of microbes responsible for organic substance decomposition induced by MF inputs. Indeed, MF addition increased the relative abundance of fermentation- and cellulysis-assoicated bacteria, together with Saprotrophic fungi. Moreover, dissolved matters derived from MF played a non-neglected role in regulating organic carbon transformation in MPs-polluted sediment. Besides, MF addition decreased the complexity of bacterial community network in MPs-polluted sediment but fungal community network became complicated. And the complexity of microbial network was MF amount-dependent. Even though stochastic process was dominated in sediment with or without MF, MF inputs enhanced the relative contribution of determinism and reduced the migration of microbial communities. A strong response of sediment microbes to MF affected sedimentary organic matters transformation driven by microbes. This work uncovered linkages between organic carbon transformation and microbes in sediment with endogenous litterfall and exogenous MPs inputs in mangroves.
本研究考察了内生源红树林凋落物（MF）输入对受外生源微塑料（MPs）污染沉积物中有机质转化的影响，并探讨了其与微生物特性的联系。MF 输入通过改善微生物的腐殖化、酶活性和碳利用能力，显著影响 MPs 污染沉积物中的有机碳转化。这种影响主要与 MF 输入诱导的有机物质分解相关微生物的富集有关。事实上，MF 添加增加了与发酵和纤维素分解相关的细菌以及腐生真菌的相对丰度。此外，MF 衍生的溶解物质在调节 MPs 污染沉积物中的有机碳转化方面发挥了不可忽视的作用。此外，MF 添加降低了 MPs 污染沉积物中细菌群落网络的复杂性，但真菌群落网络变得复杂。微生物网络的复杂性与 MF 的数量有关。尽管在有或没有 MF 的沉积物中，随机过程占主导地位，但 MF 输入增强了确定性的相对贡献，减少了微生物群落的迁移。MF 对沉积物微生物的强烈响应影响了由微生物驱动的沉积物有机物质转化。本研究揭示了内生源凋落物和外生源 MPs 输入对红树林沉积物中有机碳转化与微生物之间的联系。
