[RAW VALIDATED DATA] Properties of seawater and particulate matter from a FRRF instrument, operating in a flow-through mode on the continuous surface water sampling system during the Tara Oceans expedition 2009-2013

The Tara Oceans Expedition (2009-2013) sampled the world oceans on board a 36 m long schooner, collecting environmental data and organisms from viruses to planktonic metazoans for later analyses using modern sequencing and state-of-the-art imaging technologies. Tara Oceans Data are particularly suited to study the genetic, morphological and functional diversity of plankton. The present data set provides raw validated data of continuous measurements made with a FRRF instrument, operating in a flow-through mode during the 2009-2012 part of the expedition. It operates by exciting chlorophyll fluorescence using a series of short flashes of controlled energy and time intervals (Kolber et al, 1998). The fluorescence transients produced by this excitation signal were analysed in real-time to provide estimates of abundance of photosynthetic pigments, the photosynthetic yields (Fv/Fm), the functional absorption cross section (a proxy for efficiency of photosynthetic energy acquisition), the kinetics of photosynthetic electron transport between Photosystem II and Photosystem I, and the size of the PQ pool. These parameters were measured at excitation wavelength of 445 nm, 470nm, 505 nm, and 535 nm, allowing to assess the presence and the photosynthetic performance of different phytoplankton taxa based on the spectral composition of their light harvesting pigments. The FRRF-derived photosynthetic characteristics were used to calculate the initial slope, the half saturation, and the maximum level of Photosynthesis vs Irradiance relationship. FRRF data were acquired continuously, at 1-minute time intervals.

塔拉海洋科考航次（2009-2013年）依托一艘36米长的纵帆船开展全球海洋采样，收集了从病毒到浮游后生动物的各类生物样本与环境数据，用于后续依托现代测序技术与尖端成像技术开展分析研究。塔拉海洋数据集尤其适用于研究浮游生物的遗传、形态与功能多样性。本数据集提供了该航次2009-2012阶段中，采用流通式工作模式的快速重复激发荧光计（FRRF）所获取的经过校验的原始连续测量数据。该仪器通过一系列能量与时间间隔可控的短脉冲激发叶绿素荧光（Kolber等，1998）。研究人员对该激发信号产生的荧光瞬态进行实时分析，以此估算光合色素含量、光合量子产量（Fv/Fm）、功能吸收截面（光合能量捕获效率的替代指标）、光系统II（Photosystem II）与光系统I（Photosystem I）间光合电子传递动力学，以及质体醌库（PQ pool）的规模。上述参数在445 nm、470 nm、505 nm与535 nm的激发波长下完成测量，可基于不同浮游植物类群的光捕获色素光谱组成，评估其存在情况与光合性能。基于快速重复激发荧光计获取的光合特性数据，可计算光合-光强响应曲线的初始斜率、半饱和参数与最大光合水平。该仪器的采集数据以1分钟的时间间隔连续获取。