State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, The Research Center of Soil and Water Conservation and Ecological Environment, Chinese Academy of Sciences and Ministry of Education, Yangling, Shaanxi, China.
State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi, China.
Glob Chang Biol. 2024 Jul;30(7):e17415. doi: 10.1111/gcb.17415.
Microplastic (MP) pollution likely affects global soil carbon (C) dynamics, yet it remains uncertain how and to what extent MP influences soil respiration. Here, we report on a global meta-analysis to determine the effects of MP pollution on the soil microbiome and CO emission. We found that MP pollution significantly increased the contents of soil organic C (SOC) (21%) and dissolved organic C (DOC) (12%), the activity of fluorescein diacetate hydrolase (FDAse) (10%), and microbial biomass (17%), but led to a decrease in microbial diversity (3%). In particular, increases in soil C components and microbial biomass further promote CO emission (25%) from soil, but with a much higher effect of MPs on these emissions than on soil C components and microbial biomass. The effect could be attributed to the opposite effects of MPs on microbial biomass vs. diversity, as soil MP accumulation recruited some functionally important bacteria and provided additional C substrates for specific heterotrophic microorganisms, while inhibiting the growth of autotrophic taxa (e.g., Chloroflexi, Cyanobacteria). This study reveals that MP pollution can increase soil CO emission by causing shifts in the soil microbiome. These results underscore the potential importance of plastic pollution for terrestrial C fluxes, and thus climate feedbacks.
微塑料（MP）污染可能会影响全球土壤碳（C）动态，但目前尚不确定 MP 会以何种方式以及在何种程度上影响土壤呼吸。在这里，我们进行了一项全球荟萃分析，以确定 MP 污染对土壤微生物组和 CO 排放的影响。我们发现，MP 污染显著增加了土壤有机碳（SOC）（21%）和溶解有机碳（DOC）（12%）、荧光素二乙酸酯水解酶（FDAse）（10%）和微生物生物量（17%）的含量，但导致微生物多样性（3%）下降。特别是，土壤 C 成分和微生物生物量的增加进一步促进了土壤 CO 排放（25%），但 MPs 对这些排放的影响远高于对土壤 C 成分和微生物生物量的影响。这种效应可能归因于 MPs 对微生物生物量和多样性的相反作用，因为土壤 MP 积累招募了一些功能重要的细菌，并为特定的异养微生物提供了额外的 C 底物，同时抑制了自养类群（如绿弯菌门、蓝细菌）的生长。本研究表明，MP 污染通过改变土壤微生物组来增加土壤 CO 排放。这些结果强调了塑料污染对陆地 C 通量和气候反馈的潜在重要性。
