Microbial ecology at cabled seafloor observatories

由维多利亚大学运营的金星和海王星有线观测台为研究海洋生物如何对其环境变化作出反应的时间序列提供了前所未有的机会。我的研究计划将率先使用这些观测站来研究海洋微生物的生态学。一系列研究项目将开发一个观测工具箱，其中包括直接和间接研究对生态系统功能至关重要的微生物过程的方法和方法规程。我们将研究环境因素如何影响微生物控制氮的生物利用率、为热液喷口生物生产食物和分解沉积物中的有机碎片的方式。 直接研究将量化与环境变量有关的微生物现存量变化、群落结构和代谢过程。间接研究将侧重于生物扰动的动力学，这是影响微生物生长和代谢的一个关键物理变量。将在胡安·德富卡海岭的主要奋进热液喷口地区的海王星观测站开展两个项目。一个遥控水取样器将收集喷口流体样本，用于研究海底地下环境中与流体化学有关的微生物脱氮作用。第二个热液项目将利用遥控摄像机研究宏观微生物垫生长与流体排放和动物群放牧活动的关系。在大陆边巴克利峡谷的海王星观测站，将使用照相机和微型剖面探测器调查大型底栖动物对表层沉积物的生物扰动与季节性生境变量之间的关系。在沿海的萨尼奇湾，在金星天文台未来的水柱剖面仪仪器包的网站，我们将研究微生物硝化在透光层，强调以前观察到的不平衡的两个连续的步骤硝化（铵氧化和亚硝酸盐氧化）和潮汐混合的关系。这项工作还将有助于为2012年安装在VENUS剖面仪上的自动微生物基因分析仪准备实验。

The VENUS and NEPTUNE cabled observatories operated by the University of Victoria offer unprecedented opportunities for the time series study of how marine organisms respond to changes in their environment. My research program will pioneer the use of these observatories to study the ecology of marine microorganisms. A series of research projects will develop an observatory toolbox of approaches and methodological protocols for the direct and indirect study of microbial processes that are important to ecosystem function. We will study how environmental factors influence the way in which microbes control the bioavailability of nitrogen, produce food for hydrothermal vent organisms and decompose organic debris in sediments. Direct studies will quantify microbial standing stock variations, community structure and metabolic processes, in relation to environmental variables. Indirect studies will focus on the dynamics of bioturbation, a key physical variable that influences microbial growth and metabolism. Two projects will be undertaken at the NEPTUNE observatory site in the Main Endeavour hydrothermal vent field on the Juan de Fuca Ridge. A remotely-activated water sampler will collect vent fluid samples for a study of microbial denitrification in the subsurface environment below the seafloor, in relation to fluid chemistry. The second hydrothermal project will use remote-controlled cameras to study the dynamics of macroscopic microbial mat growth in relation to fluid discharge and faunal grazing activity. At the NEPTUNE site in Barkley Canyon, on the continental margin, cameras and micro-profiling sensors will be used to investigate the relationship of bioturbation of surface sediments by the macrofauna, to seasonal habitat variables. In coastal Saanich Inlet, at the site of the VENUS observatory's future water column profiler instrument package, we will study microbial nitrification in the photic zone, emphasizing a previously observed imbalance in the two successive steps in nitrification (ammonium oxidation and nitrite oxidation) and its relationship to tidal mixing. This work will also serve to prepare experiments for an automated microbial gene analyzer to be installed on the VENUS profiler in 2012.