Soil Plastisphere\nReinforces the Adverse Effect of\nCombined Pollutant Exposure on the Microfood Web

Microbial interactions form microfood webs, crucial for\necological\nfunctions. The steady state of these webs, shaped by cooperation and\ncompetition among trophic levels, prevents pathogen proliferation\nand invasion, maintaining soil health. Combined pollutants pose a\nwidespread environmental issue, exerting significant pressure on microfood\nwebs. However, understanding how these webs respond to combined pollutants\nin soil plastispheres, an emerging niche, remains limited. This study\nexplores trophic interactions among bacteria, fungi, and protists,\nexamining their effects on potential pathogens in three soil types\namended with Cu or disinfectant, along with their plastispheres, using\na microcosm experiment. Pollutant exposure disrupts trophic-level\ninteractions through bottom-up and top-down regulation in soils and\nplastispheres, respectively. Microfood web network topology parameters\nprove more sensitive to pollutant stress than indicators from a single\ntrophic-level community composition. Combined exposure causes greater\ndisruption to the microfood web than exposure to a single pollutant\n(Cu or didecyl dimethylammonium chloride (DDAC)). Plastisphere reinforces\nnegative impacts of combined pollutant exposure on the microfood web\nnetwork, escalating potential pathogenic bacteria. Overall, this study\ndeepens our understanding of microfood web responses under pollutant\npressure in soil plastispheres and provides valuable insights for\nhealth risk assessments of soil combined pollutants.