Phototrophic biofilms, also known as periphyton, are microbial freshwater communities that drive crucial ecological processes in streams and lakes. Gaining a deep mechanistic understanding of the biological processes occurring in natural periphyton remains challenging due to the high complexity and variability of such communities. To address this challenge, we rationally developed a workflow to construct a synthetic community by co-culturing 26 phototrophic species (i.e., diatoms, green algae, and cyanobacteria) that were inoculated in a successional sequence to create a periphytic biofilm on glass slides. We show that this community is diverse, stable, and highly reproducible in terms of microbial composition, function, and 3D spatial structure of the biofilm. We also demonstrate the ability to monitor microbial dynamics at the single species level during periphyton development and how their abundances are impacted by stressors such as increased temperature and a herbicide, singly and in combination. Overall, such a synthetic periphyton, grown under controlled conditions, can be used as a model system for theory testing through targeted manipulation.

光养生物膜，也称为附生生物，是微生物淡水群落，驱动溪流和湖泊中的关键生态过程。由于此类群落的高度复杂性和可变性，对自然附生生物中发生的生物过程进行深入的机械理解仍然具有挑战性。为了应对这一挑战，我们合理地开发了一个工作流程，通过共培养 26 种光养物种（即硅藻、绿藻和蓝细菌）来构建合成群落，这些物种按连续顺序接种，以在载玻片上形成附生生物膜。我们表明，这个群落在微生物组成、功能和生物膜的 3D 空间结构方面是多样化、稳定和高度可重复的。我们还展示了在附生植物发育过程中监测单个物种水平的微生物动态的能力，以及它们的丰度如何受到温度升高和除草剂等压力因素的影响，单独和组合。总体而言，这种在受控条件下生长的合成附生生物可以用作模型系统，通过有针对性的操作进行理论测试。