Dissolved organic matter (DOM) and base-extracted particulate organic matter (BEPOM) collected from a plankton senescence experiment from water samples offshore of North Carolina

<p>A mixed assemblage of natural phytoplankton community collected from waters offshore of North Carolina were used to create planktonic dissolved organic matter (DOM) and particulate organic matter (POM). The latter was extracted with 0.1 M NaOH to create base-extracted POM (BEPOM). Methods are reported in Kinsey et al. (2018) and Osburn et al. (2019).&nbsp;<br /> The medium used was: Natural Assemblage 2x filtered North Atlantic Surface water with f/2 nutrients; Whole water experiment - unfiltered North Atlantic Surface water with f/20 nutrients Irradiance ~70-100 umol photon m-2 s-1 (cool white bulbs); on roller table; diel cycle, 19 °C&nbsp;</p> <p>Controls:&nbsp; 0.2 um Filtered Sargasso seawater amended with f/2 nutrients; NASW (or WW) unfiltered Sargasso Seawater amended with f/20 nutrients; NASW: Sargasso seawater amended with plankton tow sample and f/2 nutrients.&nbsp; All samples were in 1.9 L bottles with minimal headspace.</p>本研究以从北卡罗来纳州近岸海域采集的天然浮游植物混合群落为实验材料，制备了浮游性溶解有机质（dissolved organic matter, DOM）与颗粒有机质（particulate organic matter, POM）。采用0.1 mol/L氢氧化钠溶液对颗粒有机质进行提取，得到碱提取颗粒有机质（base-extracted POM, BEPOM）。具体实验方法详见Kinsey等人（2018）与Osburn等人（2019）的研究成果。 实验所用培养液配置如下：天然群落组采用经2倍过滤的北大西洋表层水，并添加f/2级营养盐；全水实验组采用未过滤的北大西洋表层水，添加f/20级营养盐；光照强度约70~100 μmol光子·米⁻²·秒⁻¹，光源为冷白色荧光灯；实验置于滚床之上，设置昼夜节律循环，培养温度为19 ℃。 对照组设置如下：① 经0.2 μm过滤的马尾藻海水，添加f/2级营养盐；② NASW（即WW）组：未过滤的马尾藻海水，添加f/20级营养盐；③ NASW组：马尾藻海水添加浮游生物拖网样品，并补充f/2级营养盐。所有实验样品均置于1.9 L培养瓶中，且顶空体积尽可能最小。