Raw data of Cedar Creek Experiment

<strong>1.-Experiment </strong> The experimental design consisted of 21 populations inoculated with 1 mL water samples taken near the Cedar Bog Lake dock on July 7th. Each population consisted of a final volume of 39 mL in transparent Greiner Bio-One vented-cap culture flasks. We used a three-by-two factorial design with three nitrogen concentrations (standard BG11 medium (17.6 mM NaNO3), a reduced nitrogen BG11 medium (9 mM NaNO3), and a BG11-0 medium (without nitrogen)) and (10 mM NaCl) and without NaCl addition. To account for the effect of nutrient addition, we added a control treatment with deionized water. Three replicates population of each experimental condition were stabilized. The experiment was run for 3 weeks. Table 1: Experimental design. <strong>dH20</strong> <strong>BG11</strong> <strong>BG11 reduce Nitrogen</strong> <strong>B11 without Nitrogen </strong> <strong>BG11 +NaCl</strong> <strong>BG11 reduce Nitrogen</strong> <strong>+NaCl</strong> <strong>B11 without Nitrogen+NaC</strong>l R1 R16 R10 R4 R19 R13 R7 R2 R17 R11 R5 R20 R14 R8 R3 R18 R12 R6 R21 R15 R9 <strong>1.1 FlowCam( Fluid Imaging Technologies) Data collection</strong> 0.15 mL aliquots of each population at week three were run through a Flowcam cytometer (Fluid Imaging Technologies) at a speed of 0.14 mL/min and collect images of individual particles and estimate biovolume using total area. The 10x magnification setting was used with a calibration factor of 0.5525. For each sample, the first 1,000 images taken by FlowCam were selected for species diversity analysis. Each folder is a separate population at T3 (21 days). It contains the original run (pictures and files) and within it can be found the classification by “groups” (pictures and files). <strong>1.2 Flotation Device Technical Description</strong> Flotation Device is a suspension system to safely maintain planktonic microbial populations to carry out studies at the water temperature and light conditions of a water body. <strong>1.3 Bradford Protein Assay Data </strong> Populations were checked weekly by sampling aliquots of all the populations and running Bradford Protein Assays as a proxy for population growth.<strong>1. 实验</strong>本实验共设置21个种群，于7月7日接种取自锡达博格湖（Cedar Bog Lake）码头附近的1 mL水样。每个种群均置于带透气盖的透明Greiner Bio-One培养瓶中，最终培养体积为39 mL。本实验采用3×2析因设计，设置3种氮浓度梯度：标准BG11培养基（BG11 medium，含17.6 mM硝酸钠）、低氮BG11培养基（BG11 medium，含9 mM硝酸钠）以及无氮BG11-0培养基（BG11-0 medium，不含氮源）；同时设置2种氯化钠添加条件：添加10 mM氯化钠与不添加氯化钠。为控制营养添加的干扰效应，增设去离子水对照组。每种实验条件设置3个生物学重复种群。实验周期为3周。表1：实验设计方案。<strong>去离子水（dH₂O）</strong><strong>BG11培养基</strong><strong>低氮BG11培养基</strong><strong>无氮BG11培养基</strong><strong>BG11培养基+氯化钠</strong><strong>低氮BG11培养基+氯化钠</strong><strong>无氮BG11培养基+氯化钠</strong>R1 R16 R10 R4 R19 R13 R7 R2 R17 R11 R5 R20 R14 R8 R3 R18 R12 R6 R21 R15 R9<strong>1.1 FlowCam（流体成像技术公司，Fluid Imaging Technologies）数据采集</strong>实验第3周时，从每个种群中取0.15 mL等分试样，以0.14 mL/min的流速通过FlowCam流式细胞仪进行检测，采集单个颗粒物的图像，并通过总投影面积估算其生物体积。实验采用10倍放大倍率，校准因子为0.5525。每个样本选取FlowCam采集的前1000张图像用于物种多样性分析。每个文件夹对应T3时刻（第21天）的独立种群，文件夹内包含原始采集的图像与数据文件，同时可找到按"类群"分类的图像及对应文件。<strong>1.2 浮游装置技术说明</strong>浮游装置为一套悬浮系统，可安全维持浮游微生物种群，以便在水体原有的水温与光照条件下开展相关研究。<strong>1.3 Bradford蛋白定量实验数据</strong>每周对所有种群进行等分取样，通过Bradford蛋白定量实验作为种群生长量的替代检测指标。