CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China.
Global Innovative Centre for Advanced Nanomaterials, School of Engineering, The University of Newcastle, Callaghan, New South Wales, Australia.
Glob Chang Biol. 2023 Jul;29(14):3895-3909. doi: 10.1111/gcb.16734. Epub 2023 Apr 26.
Although the presence of nanoplastics in aquatic and terrestrial ecosystems has received increasing attention, little is known about its potential effect on ecosystem processes and functions. Here, we evaluated if differentially charged polystyrene (PS) nanoplastics (PS-NH and PS-SO H) exhibit distinct influences on microbial community structure, nitrogen removal processes (denitrification and anammox), emissions of greenhouse gases (CO , CH , and N O), and ecosystem multifunctionality in soils with and without earthworms through a 42-day microcosm experiment. Our results indicated that nanoplastics significantly altered soil microbial community structure and potential functions, with more pronounced effects for positively charged PS-NH than for negatively charged PS-SO H. Ecologically relevant concentration (3 g kg ) of nanoplastics inhibited both soil denitrification and anammox rates, while environmentally realistic concentration (0.3 g kg ) of nanoplastics decreased the denitrification rate and enhanced the anammox rate. The soil N O flux was always inhibited 6%-51% by both types of nanoplastics, whereas emissions of CO and CH were enhanced by nanoplastics in most cases. Significantly, although N O emissions were decreased by nanoplastics, the global warming potential of total greenhouse gases was increased 21%-75% by nanoplastics in soils without earthworms. Moreover, ecosystem multifunctionality was increased 4%-12% by 0.3 g kg of nanoplastics but decreased 4%-11% by 3 g kg of nanoplastics. Our findings provide the only evidence to date that the rapid increase in nanoplastics is altering not only ecosystem structure and processes but also ecosystem multifunctionality, and it may increase the emission of CO and CH and their global warming potential to some extent.
尽管纳米塑料在水生态系统和陆地生态系统中的存在已经引起了越来越多的关注，但对于其对生态系统过程和功能的潜在影响知之甚少。在这里，我们通过 42 天的微宇宙实验评估了带不同电荷的聚苯乙烯（PS）纳米塑料（PS-NH 和 PS-SO H）是否对微生物群落结构、氮去除过程（反硝化和厌氧氨氧化）、温室气体（CO 、CH 和 N O）排放以及有和没有蚯蚓的土壤的生态系统多功能性产生不同的影响。我们的结果表明，纳米塑料显著改变了土壤微生物群落结构和潜在功能，带正电荷的 PS-NH 的影响比带负电荷的 PS-SO H 更为明显。生态相关浓度（3 g kg）的纳米塑料抑制了土壤反硝化和厌氧氨氧化速率，而环境现实浓度（0.3 g kg）的纳米塑料降低了反硝化速率并增强了厌氧氨氧化速率。两种类型的纳米塑料始终抑制土壤 N O通量，抑制率为 6%-51%，而在大多数情况下，纳米塑料会增强 CO 和 CH 的排放。重要的是，尽管纳米塑料降低了 N O的排放，但在没有蚯蚓的土壤中，纳米塑料增加了总温室气体的全球变暖潜势 21%-75%。此外，在 0.3 g kg 的纳米塑料作用下，生态系统多功能性增加了 4%-12%，而在 3 g kg 的纳米塑料作用下，生态系统多功能性降低了 4%-11%。我们的研究结果提供了迄今为止唯一的证据，证明纳米塑料的快速增加不仅改变了生态系统结构和过程，而且改变了生态系统的多功能性，它可能在某种程度上增加 CO 和 CH 的排放及其全球变暖潜势。
