Zhang Linjie, Wang Chenya, Xie Bing
Shanghai Engineering Research Center of Biotransformation on Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China.
Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
Environ Sci Technol. 2025 Sep 9;59(35):18927-18935. doi: 10.1021/acs.est.5c08835. Epub 2025 Aug 22.
Microplastics (MPs) are widespread in agricultural soils and may influence emissions of greenhouse gases (GHGs), though their specific impacts remain uncertain. This study utilized conventional and network meta-analysis to evaluate the effects of long-term exposure to environmentally relevant MP concentrations. Results showed that, compared with uncontaminated soil, polypropylene increased CH emissions by 2.01 times, while polyethylene terephthalate reduced them to 0.47 times. Polybutylene adipate terephthalate (PBAT) and polylactic acid/PBAT increased CO emissions by 3.13 and 2.70 times, respectively; polyethylene raised NO emissions by 1.52 times. Other MPs had no significant impact. Most types of MPs increased GHG emissions, with conventional MPs contributing more to NO emissions and biodegradable MPs contributing more to CO emissions. Biodegradable plastics were not necessarily more environmentally friendly in terms of global warming potential. Moreover, the study summarized issues in current meta-analyses targeting MPs, emphasizing the need to prioritize MP types, account for correlations and interactions among moderators, ensure effect size independence, and address potential "P-hacking" during the discretization of continuous variables. This deepens our comprehension of the environmental impacts of MPs and provides valuable guidance for future meta-analyses to accurately assess effects of MPs.
微塑料（MPs）在农业土壤中广泛存在，可能会影响温室气体（GHGs）排放，但其具体影响仍不确定。本研究利用传统和网络荟萃分析来评估长期暴露于环境相关MP浓度的影响。结果表明，与未受污染的土壤相比，聚丙烯使CH排放量增加了2.01倍，而聚对苯二甲酸乙二酯将其降至0.47倍。聚己二酸丁二醇酯对苯二甲酸酯（PBAT）和聚乳酸/PBAT分别使CO排放量增加了3.13倍和2.70倍；聚乙烯使NO排放量增加了1.52倍。其他MPs没有显著影响。大多数类型的MPs增加了温室气体排放，传统MPs对NO排放的贡献更大，可生物降解MPs对CO排放的贡献更大。就全球变暖潜力而言，可生物降解塑料不一定更环保。此外，该研究总结了当前针对MPs的荟萃分析中的问题，强调需要对MP类型进行优先排序，考虑调节因素之间的相关性和相互作用，确保效应大小的独立性，并在连续变量离散化过程中解决潜在的“P值篡改”问题。这加深了我们对MPs环境影响的理解，并为未来准确评估MPs效应的荟萃分析提供了有价值的指导。
