Microbial community functional diversity enhances the degradation of organic matter and pollutants in the environment, but there is a growing concern that these ecosystem services may be altered by the introduction of emerging environmental contaminants including silver nanoparticles (AgNPs) into aquatic systems. We added 0, 25, 50, 75, 100, and 125 mg L⁻¹ (nominal concentrations) of citrate-AgNP and polyvinylpyrrolidone-AgNP (PVP-AgNP) each to freshwater sediment and examined their antimicrobial effects on microbial communities using community-level physiological profiling. The results showed that citrate-AgNP decreased the overall microbial catabolic activity by 80% from 1.16 ± 0.02 to 0.23 ± 08 while PVP-AgNP decreased the catabolic activity by 51% from 1.25 ± 0.07 to 0.61 ± 0.19 at 125 mg L⁻¹. Citrate-AgNP and PVP-AgNP caused a statistically significant reduction in substrate richness and substrate diversity that decreased microbial functional diversity. AgNPs decreased microbial catabolic capability and functional diversity at concentrations ranging from 0.12 ± 0.04 to 0.43 ± 0.07 mg Ag kg^-1 which are lower than the predicted concentrations in freshwater sediment. To our knowledge, this is the first study to demonstrate inhibition of microbial functional diversity by citrate-AgNP and PVP-AgNP in a pathogen impaired stream. Citrate-AgNP caused greater inhibition of carbon substrate utilization but amino acids, carbohydrates, and carboxylic acids were the most affected carbon groups which led to a shift in the metabolic fingerprint pattern of the microbial community. AgNPs decreased the catabolic capability and the ability of the microbial community to degrade organic matter and a variety of pollutants in the environment.

微生物群落功能的多样性促进了环境中有机物和污染物的降解，但人们日益关注的是，可能会通过将包括银纳米颗粒（AgNPs）在内的新兴环境污染物引入水生系统来改变这些生态系统服务。我们分别向淡水沉积物中添加了0、25、50、75、100和125 mg L ^-1（名义浓度）的柠檬酸盐-AgNP和聚乙烯吡咯烷酮-AgNP（PVP-AgNP），并使用社区-2检验了它们对微生物群落的抗菌作用。水平的生理分析。结果表明，在125 mg L ^-1时，柠檬酸盐-AgNP将整体微生物分解代谢活性从1.16±0.02降低至80％（0.23±08），而PVP-AgNP将其分解代谢活性从1.25±0.07降低51％，至0.61±0.19。。柠檬酸-AgNP和PVP-AgNP导致底物丰富度和底物多样性的统计学显着降低，从而降低了微生物功能多样性。AgNPs在0.12±0.04至0.43±0.07 mg Ag kg ^-1的浓度范围内会降低微生物的分解代谢能力和功能多样性低于淡水沉积物中的预测浓度。据我们所知，这是第一个证明柠檬酸盐-AgNP和PVP-AgNP在病原体受损流中抑制微生物功能多样性的研究。柠檬酸-AgNP对碳底物利用的抑制作用更大，但氨基酸，碳水化合物和羧酸是受影响最严重的碳基团，导致微生物群落的代谢指纹图谱发生变化。AgNPs降低了分解代谢的能力以及微生物群落降解环境中有机物和各种污染物的能力。