Phytoplankton samples collected on the CLIVAR voyage of the Aurora Australis, 2001

Locations of sampling sites for ASAC project 40/1343 on voyage 3 of the Aurora Australis in the 2001/2002 season. The dataset also contains information on chlorophyll, carotenoids, coccolithophorids and species indentification and counts.

The data can be accessed via the Biodiversity Database at the provided URL.

From the abstract of the referenced publication:

Variations of phytoplankton assemblages were studied in November-December 2001, in surface waters of the Southern Ocean along a transect between the Sub-Antarctic Zone (SAZ) and the Seasonal Ice Zone (SIZ; 46.9-64.9 degrees S; 142-143 degrees E; CLIVAR-SR3 cruise). Two regions had characteristic but different phytoplankton assemblages. Nanoflagellates (less than 20 microns) and pico-plankton (~2 microns) occurred in similar concentrations along the transect, but were dominant in the SAZ, Sub-Antarctic Front (SAF), Polar Front Zone (PFZ) and the Inter-Polar Front Zone (IPFZ), (46.9-56.9 degrees S). Along the entire transect their average cell numbers in the upper 70 m of water column, varied from 300,000 to 1,100,000 cells per litre. Larger cells (greater than 20 microns), diatoms and dinoflagellates, were more abundant in the Antarctic Zone-South (AZ-S) and the SIZ (60.9-64.9 degrees S). In AZ-S and SIZ diatoms ranged between 270,000 and 1,200,000 cells per litre, dinoflagellates from 31,000 to 102,000 cells per litre. A diatom bloom was in progress in the AZ-S showing a peak of 1,800,000 cells per litre. Diatoms were dominated by Pseudo-nitzschia spp., Fragilariopsis spp., and Chaetoceros spp. Pseudo-nitzschia spp. outnumbered other diatoms in the AZ-S. Fragilariopsis spp. were most numerous in the SIZ. Dinoflagellates contained autotrophs (eg Prorocentrum) and heterotrophs (Gyrodinium/Gymnodinium, Protoperidinium). Diatoms and dinoflagellates contributed most to the cellular carbon: 11-25 and 17-124 micrograms of carbon per litre, respectively. Small cells dominated in the northern region characterised by the lowest N-uptake and new production of the transect. Larger diatom cells were prevalent in the southern area with higher values of N-uptake and new production. Diatom and nanoflagellate cellular carbon contents were highly correlated with one another, with primary production, and productivity related parameters. They contributed up to 75% to the total autotrophic C biomass. Diatom carbon content was significantly correlated to nitrate uptake and particle export, but not to ammonium uptake, while flagellate carbon was well correlated to ammonium uptake, but not to export. Diatoms have contributed highly to particle export along the latitudinal transect, while flagellates played a minor role in the export.

This work was completed as part of ASAC projects 40 and 1343.

See also the related metadata record, "Spring Phytoplankton Assemblages in the Southern Ocean Between Australia and Antarctica".

本数据集记录了2001/2002航季“南极光号”（Aurora Australis）第三次航行中ASAC项目40/1343的采样点位分布。本数据集同时包含叶绿素、类胡萝卜素、颗石藻（coccolithophorids）的相关数据，以及物种鉴定与计数信息。

可通过提供了访问URL的生物多样性数据库获取本数据集。

引用文献的摘要如下：
本研究于2001年11-12月，沿亚南极带（Sub-Antarctic Zone, SAZ）与季节性海冰带（Seasonal Ice Zone, SIZ；南纬46.9°-64.9°，东经142°-143°；CLIVAR-SR3航次）之间的断面，对南大洋表层水体的浮游植物群落变化展开了调查。两个区域拥有特征各异的浮游植物群落。
微型鞭毛虫（粒径<20μm）与超微型浮游生物（粒径约2μm）在整个断面上的丰度相近，但在亚南极带、亚南极锋（Sub-Antarctic Front, SAF）、极锋带（Polar Front Zone, PFZ）以及极间锋带（Inter-Polar Front Zone, IPFZ，南纬46.9°-56.9°）为优势类群。在整个断面的上层70m水体中，这类微型生物的平均细胞丰度介于3×10^5至1.1×10^6个/升之间。
大型细胞（粒径>20μm）即硅藻与甲藻，在南南极区（Antarctic Zone-South, AZ-S）与季节性海冰带（南纬60.9°-64.9°）中丰度更高。在南南极区与季节性海冰带中，硅藻的丰度介于2.7×10^5至1.2×10^6个/升，甲藻丰度则介于3.1×10^4至1.02×10^5个/升。
南南极区当时正处于硅藻水华期，细胞丰度峰值达1.8×10^6个/升。该区域硅藻主要由拟菱形藻属（Pseudo-nitzschia spp.）、脆杆藻属（Fragilariopsis spp.）与角毛藻属（Chaetoceros spp.）构成优势类群。南南极区中，拟菱形藻属的丰度高于其他硅藻类群；季节性海冰带中则以脆杆藻属为绝对优势类群。
甲藻类群包含自养类群（如原甲藻属*Prorocentrum*）与异养类群（如旋沟藻属/裸甲藻属*Gyrodinium/Gymnodinium*、多甲藻属*Protoperidinium*）。硅藻与甲藻对细胞碳库的贡献最大，分别为11~25μg C/升与17~124μg C/升。
小型细胞类群在断面最北部区域占据优势，该区域的氮摄取量与新生产力均为全断面最低水平；大型硅藻细胞则在南部区域占据优势，该区域的氮摄取量与新生产力均处于较高水平。
硅藻与微型鞭毛虫的细胞碳含量彼此间存在高度相关性，同时与初级生产力及生产力相关参数显著相关。二者合计可占总自养碳生物量的75%。
硅藻碳含量与硝酸盐摄取量及颗粒碳输出量呈显著相关，但与铵盐摄取量无明显关联；而微型鞭毛虫碳含量则与铵盐摄取量显著相关，与颗粒碳输出量无明显关联。在该经纬度断面上，硅藻对颗粒碳输出的贡献极高，而微型鞭毛虫的贡献则相对有限。

本研究作为ASAC项目40与1343的一部分完成。

亦可参考相关元数据记录：《澳南之间南大洋春季浮游植物群落》（"Spring Phytoplankton Assemblages in the Southern Ocean Between Australia and Antarctica"）。