16S Sequencing from Ontario CSMI Cruise 2023

Microbial communities are essential for maintaining healthy aquatic ecosystems, forming the foundation of the food web, and regulating water quality through nutrient cycling. Large lakes, such as the Laurentian Great Lakes, display considerable intra-lake variability, characterized by nearshore-offshore gradients, point sources like cities and rivers, and spatial heterogeneity driven by seasonal hydrodynamic circulation patterns. However, there is still a gap in understanding how spatial variability impacts microbial abundance and community composition, along with implications for microbial metabolism and nutrient cycling. Using metabarcoding, flow cytometry, and water quality analyses, we mapped microbial biodiversity in Lake Ontario, achieving novel spatial breadth and resolution. Our findings emphasize the critical role that stratification and circulation play in shaping microbial communities and their ability to cycle nutrients

微生物群落在维持健康水生生态系统、构建食物网基础以及通过养分循环调控水质方面发挥着不可或缺的作用。诸如劳伦琴五大湖（Laurentian Great Lakes）这类大型湖泊，湖内变异性显著，具体表现为近岸-离岸梯度、城市与河流等点源污染，以及受季节性水动力环流模式驱动的空间异质性。然而当前学界对空间变异如何影响微生物丰度与群落组成，及其对微生物代谢和养分循环的潜在影响仍缺乏清晰认知。本研究采用元条形码测序（metabarcoding）、流式细胞术（flow cytometry）与水质分析技术，对安大略湖（Lake Ontario）的微生物多样性进行了系统性测绘，实现了前所未有的空间覆盖广度与分辨率。研究结果凸显了水体层化与环流在塑造微生物群落及其介导养分循环能力方面的关键作用。