Ma Renjie, Xu Zining, Sun Jiayi, Li Dongrui, Cheng Zhen, Niu Yali, Guo He, Zhou Jian, Wang Tiecheng
College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, Shaanxi 712100, PR China.
College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, PR China.
J Hazard Mater. 2023 Oct 5;459:132326. doi: 10.1016/j.jhazmat.2023.132326. Epub 2023 Aug 16.
As microplastics (MPs) are organic polymers with a carbon-based framework, they may affect nutrient cycling. Information regarding how MPs influence N, P, and C cycling and the underlying driving force remains lacking. N, P, and C cycling induced by soil hydraulic properties under MPs exposure (including polyethylene (PE), polyvinyl chloride (PVC), polystyrene (PS), polypropylene (PP)) in the natural environment were investigated in this study. MPs exposure increased the soil water content (11.2-84.5%) and reduced bulk density (11.4-42.8%); soil saturated hydraulic conductivity increased by 7.3-69.4% under PP and PE exposure. MPs exposure led to increases in available phosphorus, NO-N, NH-N, and soil organic matter; the bacterial communities related to N and C cycling were significantly changed. Expression levels of soil N and C cycling-related genes were enhanced under low concentrations (0.5% and 2%) of MPs, except PVC; consequently, soil nitrogen storage and organic carbon storage increased by 12-75% and 6.7-93%, respectively. Correlation analyses among soil hydraulic properties, bacterial communities, and functional genes related to nutrient cycling revealed that soil hydraulic properties (including soil water content, saturated water capacity, and soil saturated hydraulic conductivity) were the dominant factors affecting soil N and C storage under MPs exposure.
由于微塑料（MPs）是具有碳基骨架的有机聚合物，它们可能会影响养分循环。关于微塑料如何影响氮、磷和碳循环以及潜在驱动力的信息仍然缺乏。本研究调查了在自然环境中微塑料（包括聚乙烯（PE）、聚氯乙烯（PVC）、聚苯乙烯（PS）、聚丙烯（PP））暴露下，土壤水力性质诱导的氮、磷和碳循环。微塑料暴露增加了土壤含水量（11.2 - 84.5%）并降低了容重（11.4 - 42.8%）；在聚丙烯和聚乙烯暴露下，土壤饱和导水率增加了7.3 - 69.4%。微塑料暴露导致有效磷、硝态氮、铵态氮和土壤有机质增加；与氮和碳循环相关的细菌群落发生了显著变化。在低浓度（0.5%和2%）的微塑料（聚氯乙烯除外）作用下，土壤氮和碳循环相关基因的表达水平增强；因此，土壤氮储量和有机碳储量分别增加了12 - 75%和6.7 - 93%。土壤水力性质、细菌群落和与养分循环相关的功能基因之间的相关性分析表明，土壤水力性质（包括土壤含水量、饱和持水量和土壤饱和导水率）是微塑料暴露下影响土壤氮和碳储量的主要因素。
