Long-Term Ecological Research on the Antarctic Marine Ecosystem: An Ice-Dominated Environment

该提案将继续进行第二个为期六年的帕尔默长期生态研究计划，该计划的重点是南极半岛西部地区的海洋生态系统。本研究的一个核心原则是，海冰的年度进退是南极海洋生态系统结构和功能时空变化的主要物理决定因素，从年度总产量到海鸟的繁殖成功。我们目前正在评估一些可测试的假设，这些假设将海冰与以下因素联系起来：季节性初级生产的时间和规模，微生物圈和颗粒沉积的动态，磷虾的丰度，分布和招募，以及顶端捕食者的繁殖成功和生存。总体目标是：(1)记录年度海冰的年际变化以及相应的物理、化学、光学、初级生产和次生生产者和顶端捕食者的生活史参数；(2)为了解南极海洋生态系统内的生态现象和过程创造了重要的数据遗产；(4)构建生态系统过程与环境变量之间的联系模型，模拟生态系统的时空关系，并利用这些模型预测和验证冰-生态系统动力学。自1991年以来，该计划包括在该地区部分区域网格的年度和季节性巡航期间进行空间采样，以及在帕尔默站附近地区从春季到秋季（10月至3月）进行时间采样。该方案旨在在一个区域尺度网格内的多个空间尺度上进行采样，允许在季节和年时间尺度上重复采样，从而解决短期和长期的生态现象，并为具体的机制研究提供基础。迄今为止，已经有七个区域巡航和两个额外的巡航强调微生物动力学（表1和2）。在每年的巡航中，从船上常规取样和监测核心变量。文件和数据存储是通过加州大学圣巴巴拉分校计算地球系统科学研究所的一个电子中心组织的，该中心也在需要时作为数据存档。有核心数据、数据集和元数据的联机定义，组织这些定义是为了促进快速信息交换和联机数据文件编制。这个多学科项目位于气候敏感地区，有可能在自然变化的背景下探测南极生态系统的长期趋势。

9632763 Smith This proposal continues, for a second six year period, the Palmer Long-Term Ecological Research program which focuses on the marine ecosystem in the western Antarctic Peninsula region. A central tenet of this research is that the annual advance and retreat of sea ice is a major physical determinant of spatial and temporal changes in the structure and function of the Antarctic marine ecosystem, from total annual primary production to breeding success in seabirds. We are currently evaluating a number of testable hypotheses linking sea ice to: the timing and magnitude of seasonal primary production, the dynamics of the microbial loop and particle sedimentation, krill abundance, distribution, and recruitment, and the breeding success and survival of apex predators. The overall objectives are to: (1) document the interannual variability of annual sea ice and the corresponding physics, chemistry, optics, primary production and the life-history parameters of secondary producers and apex predators within the area, (2) create a legacy of critical data for understanding ecological phenomena and processes within the Antarctic marine ecosystem, (3) identify the processes that cause variation in physical forcing and the subsequent biological response among the representative trophic levels, (4) construct models that link ecosystem processes to environmental variables, which simulate spatial/temporal ecosystem relationships, and employ such models to predict and validate ice-ecosystem dynamics. Since 1991 the program has included spatial sampling during annual and seasonal cruises in portions of our regional grid in the region and temporal sampling from spring through fall (October to March) in the area adjacent to Palmer Station. The program was designed to sample at multiple spatial scales within one regional scale grid, permitting repeated sampling on both seasonal and annual time scales, thus addressing both short and long -term ecological phenomena, as well as providing a basis for specific mechanistic studies. To date, there have been seven regional cruises and two additional cruises emphasizing microbial dynamics (Tables 1 and 2). Core variables routinely sampled and monitored from shipboard during annual cruises. Documentation and data storage are organized through an electronic hub at the Institute for Computational Earth System Science at the University of California at Santa Barbara which also serves as a data archive as needed. There are on-line definitions of core data, datasets and metadata, organized to facilitate rapid information exchange and on-line data documentation. This multidisciplinary project, sited in a climatically sensitive region, has the potential to detect, against a background of natural variability, long term trends in the Antarctic ecosystem.