Microbial metabolism upholds a fundamental role in the sustainability of water ecosystems. However, how microorganisms surviving in low-concentration substrate water environments, including the existence of emerging compounds of interest, remains unclear. In this review, microbial strategies for concentrating, utilizing, and metabolizing of low concentration substrates were summarized. Microorganisms develop substrate-concentrating strategies at both the cell and aggregate levels in substrate-limited settings. Following, microbial uptake and transport of low-concentration substrates are facilitated by adjusting physiological characteristics and shifting substrate affinities. Finally, metabolic pathways, such as mixed-substrate utilization, syntrophic metabolism, dynamic response to nutrient variation, and population density-based mechanisms allow microorganisms to efficiently utilize low-concentration substrates and to adapt to challenging oligotrophic environments. All these microbial strategies will underpin devising new approaches to tackle environmental challenges and drive the sustainability of water ecosystems, particularly in managing low-concentration contaminants (i.e., micropollutants).

微生物代谢在水生态系统的可持续性中发挥着重要作用。然而，微生物如何在低浓度底物水环境中生存，包括新出现的感兴趣化合物的存在，仍不清楚。在这篇综述中，总结了微生物浓缩、利用和代谢低浓度底物的策略。在底物有限的环境中，微生物在细胞和聚集体水平上开发底物浓缩策略。接下来，通过调整生理特性和改变底物亲和力来促进微生物对低浓度底物的摄取和运输。最后，代谢途径，如混合底物利用、互养代谢、对营养变化的动态响应和基于种群密度的机制，使微生物能够有效地利用低浓度底物并适应具有挑战性的寡营养环境。所有这些微生物策略将支持设计新方法来应对环境挑战并推动水生态系统的可持续性，特别是在管理低浓度污染物（即微污染物）方面。