Planting\nEnhances\nSoil Resistance to Microplastics:\nEvidence from Carbon Emissions and Dissolved Organic Matter Stability

Microplastics (MPs) have become a\nglobal hotspot due\nto their widespread\ndistribution in recent years. MPs frequently interact with dissolved\norganic matter (DOM) and microbes, thereby influencing the carbon\nfate of soils. However, the role of plant presence in regulating MPs-mediated\nchanges in the DOM and microbial structure remains unclear. Here,\nwe compared the mechanisms of soil response to 3 common nonbiodegradable\nMPs in the absence or presence of radish (Raphanus\nsativus L. var. <i>radculus Pers</i>) plants.\nFourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS)\nanalysis revealed that MPs reduced the chemodiversity and biodiversity\nof dissolved organic matter (DOM). MPs enhanced the degradation of\nlignin-like compounds and reduced the DOM stability. Comparative analysis\nshowed that MPs caused less disturbance to the microbial composition\nand metabolism in planted soil than in unplanted soil. In unplanted\nsoil, MPs stimulated fermentation while upregulating photoautotrophic\nactivity in planted soil, thereby enhancing system stability. The\nrhizosphere effect mitigated MPs-induced CO<sub>2</sub> emissions.\nOverall, our study highlights the crucial role of rhizosphere effects\nin maintaining ecosystem stability under soil microbe-DOM-pollutant\ninteractions, which provides a theoretical basis for predicting the\nresistance, resilience, and transitions of the ecosystem upon exposure\nto the anthropogenic carbon source.