Phytoplankton pigment data collected during the ABRACOS 1 and 2 surveys performed along the northeast Brazilian continental shelf, slope and open ocean

samples were collected during the “acoustics along the brazilian coast (abracos)” oceanographic campaigns, carried out in austral spring (30 august - 20 september of 2015 - abraços1; bertrand, 2015) and fall (9 april - 9 may of 2017 - abraços 2; bertrand, 2017) on board the french r/v antea. spring 2015 and fall 2017 are representative of canonical spring and fall conditions in terms of thermohaline structure and currents dynamics (assunção et al., 2020; dossa et al., 2021). water sampling for pigments was carried out using a rosette at four depths defined by ctd profiles: surface, mixed layer, deep chlorophyll maximum (dcm) (which showed a mean depth of 100 m in spring and 80 m in fall) and at 200 m. in shelf shallow stations (< 50 m depth), where no peak of fluorescence was observed, the dcm and 200 m samplings were replaced by a sampling depth at ~10 m above the bottom. for each station and sampled depth, 500 ml of water were filtered in whatman gf/f glass fiber for the estimation of pigment concentrations of the total phytoplankton community. size fractionation of water samples was done using 20 μm filter meshes to distinguish the pico- and nanophytoplankton from total phytoplankton pigments. microphytoplankton fraction (> 20 μm), was estimated by the difference between total and < 20 μm fractions. filters were stored at 80 ◦c for subsequent hplc pigment analysis.chemotaxonomic analysis was carried out on an agilent technology 1200 series hplc following the lov method described in hooker et al. (2000), to assess phytoplankton biomass and diversity. pigments were extracted in 100% methanol in the dark for 5 min at 4◦c. samples were then sonicated and filtered on cellulose acetate filters to remove cell debris. a 600 μl aliquot was diluted with 150 μl milli-q water. for the analysis, 125 μl of this solution was taken and diluted in an injection loop with 125 μl of a 28 mm solution of tetrabutyl ammonium acetate. the pigments were then separated on a zorbaxeclipse xdb-c8 column from agilent technology, with 3 mm in diameter,150 mm in length and 3.5 μm in porosity. the column temperature was maintained at 60 ◦c and the flow rate at 0.55 ml min 1. the separation was based on a linear gradient between a solution of methanol/tetrabutyl ammonium acetate 28 mm, 70:30 (v/v), and a 100% solution of methanol. chlorophyll-a + divinyl chlorophyll-a were used to determine total phytoplankton biomass (tchl-a), while all other pigment markers allowed identifying major algal groups (table 1). the hplc system was calibrated with external standards (dhi water and environment, horsholm, denmark).

本研究样本采集自“巴西海岸声学调查（Abraços）”海洋学考察活动，该活动分别在澳大利亚春季（2015年8月30日至9月20日——Abraços1；Bertrand，2015）和秋季（2017年4月9日至5月9日——Abraços 2；Bertrand，2017）期间，于法国R/V Antea号科考船上执行。2015年春季和2017年秋季在热盐结构及环流动力学方面，代表了典型的春季和秋季条件（Assunção等，2020；Dossa等，2021）。色素的水样采集利用CTD剖面确定的四个深度进行：表层、混合层、深层叶绿素最大值层（DCM，春季平均深度为100米，秋季为80米）以及200米。在大陆架浅水站（水深<50米），由于未观察到荧光峰值，DCM和200米的水样采集被替换为距海底约10米深度的采样。对于每个站点的每个采样深度，使用Whatman GF/F玻璃纤维滤纸过滤500毫升水，以估计总浮游植物群落中的色素浓度。通过20微米滤网对水样进行粒径分级，以区分微型浮游植物和总浮游植物色素。微型浮游植物部分（>20微米）通过总与<20微米部分的差值进行估算。滤纸在80℃下储存，以备后续的高效液相色谱（HPLC）色素分析。化学分类分析采用Agilent技术1200系列HPLC，遵循Hooker等（2000）所述的Lov方法进行，以评估浮游植物生物量和多样性。色素在4℃的黑暗环境中用100%甲醇提取5分钟。样品随后进行超声波处理，并通过醋酸纤维素滤纸过滤，以去除细胞碎片。取600微升样品，用150微升Milli-Q水稀释。分析时，取125微升此溶液，用125微升28mm四丁基铵醋酸盐溶液进行稀释。色素随后在Agilent技术Zorbax Eclipse XDB-C8柱上进行分离，该柱直径为3毫米，长度为150毫米，孔径为3.5微米。柱温维持在60℃，流速为0.55毫升/分钟。分离基于甲醇/四丁基铵醋酸盐溶液28mm，70:30（体积比），与100%甲醇溶液之间的线性梯度。叶绿素a和二乙烯基叶绿素a用于确定总浮游植物生物量（TChl-a），而所有其他色素标记则允许识别主要藻类群体（见表1）。HPLC系统以外部标准（DHI Water and Environment，Horsholm，丹麦）进行校准。