Response of antarctic marine diatoms to environment modification

Environmental manipulation and competition experiments on cultured and natural diatoms will identify the response of key taxa to environment modification. Understanding the environmental factors governing diatom distribution and natural variability will provide a basis to interpret palaeo-environment records, and allow predictions how this temperature-sensitive ecosystem will respond to future change.Environmental manipulation and competition experiments using diatoms will identify the response of key taxa to environment modification. Understanding the environmental factors governing their distribution and natural variability will provide a basis to interpret palaeo-environment records, and allow predictions how this temperature-sensitive ecosystem will respond to future change.Diatoms for the experiments were collected in 2002 (Aurora Australia, Voyage 1) and 2003 (Aurora Australis, Voyage 1). On each occasion water from the ship's online seawater tap was filtered through a 20 micrometre plankton net for up to one hour into a sample jar. A portion of the sample was preserved in lugol's iodine for later phytoplankton analysis, and the rest of the sample maintained alive in the dark in seawater at a constant low temperature. The live sample is maintained at the AAD for culturing and environment manipulation and competition experiments.Project 2364Twelve water samples were collected from 23/10/03 to 27/10/03, in open seawater between 60 degrees 45' S and 50 degrees 02' S. At each site, the following data were recorded from the ship's data logger: latitude, longitude, UTC time, local time, water depth, salinity, water temperature, fluorescence, UVB, and conductivity.针对培养及天然硅藻开展环境调控与竞争实验，可明确关键类群对环境改造的响应。解析调控硅藻分布与自然变异性的环境因子，可为古环境记录的解译提供依据，并能预测这一温度敏感型生态系统将如何响应未来环境变化。 通过硅藻开展的环境调控与竞争实验，可明确关键类群对环境改造的响应。解析调控其分布与自然变异性的环境因子，可为古环境记录的解译提供支撑，并可预测这一温度敏感型生态系统对未来环境变化的响应趋势。 本实验所用硅藻分别于2002年（澳大利亚号极光科考船，航次1）与2003年（南极光号极光科考船，航次1）采集。每次采样时，将科考船在线海水龙头采集的海水经20微米浮游生物网过滤，时长不超过1小时，收集至样品瓶中。取部分样品用卢戈碘液（Lugol's iodine）固定，用于后续浮游植物分析；剩余样品则置于黑暗环境下的恒温低温海水中活体保存。该活体样品留存于澳大利亚南极局（Australian Antarctic Division，下称AAD），用于后续培养、环境调控及竞争实验。 项目2364 该项目共采集12份海水样品，采样时间为2003年10月23日至10月27日，采样区域为南纬60°45′至50°02′的开阔海域。每个采样站位均通过科考船数据记录仪记录以下数据：纬度、经度、协调世界时（UTC）时间、当地时间、水深、盐度、水温、荧光值、紫外线B（UVB）辐射及电导率。