CarbonBridge August 2014: Zooplankton abundance, biovolume and size structure along transect E north of Svalbard

Data on zooplankton abundance and biovolume were collected in concert with data on the biophysical environment at 7 stations along a transect north of Svalbard, crossing the Atlantic Water inflow into the Arctic Ocean, in August 2014. The data were sampled along vertical profiles by a Laser Optical Plankton Counter (LOPC; ODIM-Brooke Ocean Rolls Royce Canada Ltd., Herman et al. 2004) and a Conductivity-Temperature-Depth Sensor (CTD, Seabird 19plusV2, Seabird Electronics Inc., USA), both mounted on a sturdy rosette frame. Sampling depth was from surface to ca. 10 m above the bottom, but restricted to 1000 m at maximum, only down profiles are used. Based on the LOPC data, abundance (individuals/m**3) and biovolume (mm**3/m**3) were calculated as described in the LOPC Software Operation Manual [(Anonymous, 2006), http://www.brooke-ocean.com/index.html]. LOPC data were regrouped into 49 size groups of equal log10(body volume) increments, see Edvardsen et al. (2002, doi:10.3354/meps227205). LOPC data quality was checked as described in Basedow et al. (2013, doi:10.1016/j.pocean.2012.10.005). CTD data were screened for erroneous (out of range) values and then averaged to the same frequency as the LOPC data (2 Hz). All data were processed using especially developed scripts in the python programming language. The LOPC is an optical instrument designed to count and measure particles (0.1 to 30 mm equivalent spherical diameter) in the water column, see Herman et al., (2004, doi:10.1093/plankt/fbh095). In addition to zooplankton also particles are registered by the LOPC and might contribute to the small size classes in this data set, see discussion in Espinasse et al. (in press). The size of particles as equivalent spherical diameter (ESD) was computed as described in the manual (Anonymous, 2006), and in more detail in Checkley et al. (2008, doi:10.4319/lo.2008.53.5_part_2.2123) and Gaardsted et al. (2010, doi:10.1111/j.1365-2419.2010.00558.x).2014年8月，研究团队在斯瓦尔巴德以北横跨大西洋水团流入北冰洋通道的断面上，于7个站位同步采集了浮游动物丰度与生物体积数据，并同步获取了对应站位的生物物理环境数据。数据通过搭载于坚固多管采水器框架上的激光光学浮游生物计数器（Laser Optical Plankton Counter, LOPC; ODIM-Brooke Ocean Rolls Royce Canada Ltd., Herman et al. 2004）与温盐深传感器（Conductivity-Temperature-Depth Sensor, CTD, Seabird 19plusV2, Seabird Electronics Inc., USA）沿垂直剖面采集完成，采样深度范围为表层至距海底约10米处，最大采样深度限制为1000米，且仅使用下行剖面数据。基于LOPC采集数据，参照《LOPC软件操作手册》[(Anonymous, 2006), "http://www.brooke-ocean.com/index.html"]所述方法，计算得到浮游动物丰度（单位：ind./m³）与生物体积（单位：mm³/m³）。LOPC采集数据被重新划分为49个以log₁₀(个体体积)为等增量的尺寸组别，详细信息参见Edvardsen等（2002，doi:10.3354/meps227205）。LOPC数据的质量检查流程参照Basedow等（2013，doi:10.1016/j.pocean.2012.10.005）所述方法执行。CTD数据首先被筛除超出合理范围的错误值，随后被平均至与LOPC数据一致的采样频率（2 Hz）。所有数据均通过基于Python编程语言开发的专用脚本完成处理。LOPC是一款光学类仪器，用于计数并测量水柱内粒径范围为0.1~30 mm的等效球形直径颗粒，详细信息参见Herman等（2004，doi:10.1093/plankt/fbh095）。除浮游动物外，LOPC同样会记录水体中的其他悬浮颗粒，此类颗粒可能会对本数据集的小型尺寸组别产生贡献，相关讨论详见Espinasse等（即将刊出）。等效球形直径（Equivalent Spherical Diameter, ESD）的计算方法参照操作手册（Anonymous, 2006），详细推导过程可见Checkley等（2008，doi:10.4319/lo.2008.53.5_part_2.2123）与Gaardsted等（2010，doi:10.1111/j.1365-2419.2010.00558.x）。