U.S. JGOFS Southern Ocean Process Study: Zooplankton Processes

9634052亨特利本研究项目是美国联合全球海洋通量研究(JGOFS)南大洋方案的一部分，旨在(1)更好地了解南大洋有机和无机碳的通量，(2)确定调节这些通量的大小和变化的物理、生态和生物地球化学因素和过程，以及(3)将这些通量置于当代全球碳循环的背景下。这项工作是在南大洋实验中合作的44个项目之一。南大洋实验是一项为期三年的努力，位于南极极地前锋地带以南，旨在追踪碳通过有机和无机路径从空气-海洋界面穿过整个水柱进入海底沉积物的流动。该实验将利用RVIB纳撒尼尔·B·帕尔默和R/V汤普森。这一具体项目是对南极极地锋区和罗斯海浮游动物碳利用的中尺度空间分布的季节性研究。有强有力的证据表明，浮游动物对颗粒物质的排放可以对南大洋高度可变和周期性的生物来源碳通量做出重大贡献。所采用的研究方法将在南极极地锋面带和罗斯海研究区域的变异性--涡旋分辨空间尺度和季节时间尺度--的尺度上量化中大型浮游动物群落的粪便总产量。量化过程将取决于在极地前锋区使用安装在SeaSoar上的光学浮游生物计数器测量浮游动物的丰度和分布，在罗斯海研究区使用安装在网络上的光学浮游生物计数器测量浮游动物的数量和分布，以及在两个区域进行声流测量。摄食率的实验测量将针对南极浮游动物食草动物的主要物种的体重、食物可获得性和昼夜周期建立经验关系。然后将这些关系与生物量和分布的测量相结合，以计算总粪便产生率。该办法涉及最有可能在浮游动物产生的生物源通量中引起最大变异性的因素：(1)浮游动物生物量的变异性，以及浮游动物生物量可利用的食物，在水平10公里和垂直10米的尺度上，(2)季节变异性，以及(3)可归因于浮游动物本身的大小-频率分布的变异性。研究结果将量化浮游动物在南大洋碳通量过程中的作用，从而更好地了解南大洋的碳循环。***

9634052 Huntley This research project is part of the US Joint Global Ocean Flux Study (JGOFS) Southern Ocean Program aimed at (1) a better understanding of the fluxes of carbon, both organic and inorganic, in the Southern Ocean, (2) identifying the physical, ecological and biogeochemical factors and processes which regulate the magnitude and variability of these fluxes, and (3) placing these fluxes into the context of the contemporary global carbon cycle. The work is one of forty-four projects that are collaborating in the Southern Ocean Experiment, a three-year effort south of the Antarctic Polar Frontal Zone to track the flow of carbon through its organic and inorganic pathways from the air-ocean interface through the entire water column into the bottom sediment. The experiment will make use of the RVIB Nathaniel B. Palmer and the R/V Thompson. This specific project is a seasonal study of the mesoscale spatial distribution of the carbon utilization by zooplankton in the Antarctic Polar Frontal Zone and the Ross Sea. There is strong evidence to indicate that the egestion of pellets by zooplankton can contribute significantly to a highly variable and episodic biogenic carbon flux in the Southern Ocean. The research approach used will quantify the rate of total fecal production by the meso- and macrozooplankton community at scales that dominate the variability -- eddy-resolving spatial scales and seasonal time scales -- in both the Antarctic Polar Frontal Zone and the Ross Sea study regions. The process of quantification will depend upon measurements of zooplankton abundance and distribution using a SeaSoar-mounted Optical Plankton Counter (OPC) in the Polar Frontal Zone, a net-mounted OPC in the Ross Sea study area, and underway acoustic current measurements in both regions. Experimental measurements of ingestion rate will be directed at developing empirical relationships to body weight, food availability, and diel periodicity for the p rincipal species of Antarctic zooplankton grazers. These relationships will then be combined with measurements of biomass and distribution to compute the rate of total fecal production. The approach addresses those factors that are most likely to give rise to the greatest variability in zooplankton-produced biogenic flux: (1) variability in zooplankton biomass, and the food available to that biomass, on scales of ten kilometers in the horizontal and ten meters in the vertical, (2) seasonal variability, and (3) variability that is attributable to the size-frequency distribution of the zooplankton themselves. The results will quantify the role of zooplankton in carbon flux processes of the Southern Ocean, leading to a better understanding of the Southern Ocean carbon cycle. ***