Collaborative Research: BEST: Mesozooplankton-microbial food web interactions in a climatically changing sea ice environment

俄勒冈州立大学提供的资金用于分析海冰条件变化对浮游生物食物网结构的影响，重点是微型浮游动物和中型浮游动物的营养联系以及春季海冰条件下白令海浮游植物大量繁殖的命运。为此，主要研究人员计划在冰、冰边和开放水域条件下进行一系列实验，特别是考虑到分离冰藻的重要性，如果存在，作为次要消费者的食物来源。作为这项工作的一部分，他们将确定浮游植物、微型浮游动物和中型浮游动物组合的常存量生物量、组成和大小结构，测量微型浮游动物的生长和中型浮游动物的繁殖率，测量异养原生生物和中型浮游动物优势种的放牧率和猎物偏好。它们还将确定浮游生物，特别是易碎形式的浮游植物，如殖民地浮游植物的细尺度垂直分布，以确定与水文特征有关的浮游生物/颗粒的薄层。他们的合作研究将明确解决以前未在亚北极地区探索的营养联系。他们假设，全球变暖导致的生态系统结构变化，例如季节性海冰减少，将改变这些营养相互作用，从而改变该地区藻类生产的最终命运。他们计划参加在BEST实地项目期间为春季海冰状况提出的三次年度巡航。他们将在BEST研究区内沿横断面的指定站点进行一整套分析（常住种群测定和速率测量）。丰度和速率测量将结合起来确定相对的微型浮游动物和中型浮游动物放牧的影响。虽然从该项目中获得的直接测量和观察将使主要研究人员能够详细描述白令海东部陆架的微型浮游动物和中型浮游动物及其放牧影响，但他们获得的数字也将为作为BEST的一部分开发的生态系统模型提供强有力的约束。这些模型将作为一个重要的工具，在综合的集体理解得出了最好的调查员。

Sherr 0732301Oregon State UniversityFunds are provided for an analysis of the impact of changing sea ice conditions on planktonic food web structure, focusing on microzooplankton and mesozooplankton trophic linkages and the fate of phytoplankton blooms in the Bering Sea during spring sea ice conditions. To this end, the principal investigators plan to conduct experiments over a range of ice, ice edge, and open water conditions, and, particularly, will consider the importance of detached ice algae, when present, as a food source for the secondary consumers. As part of this effort, they will determine standing stock biomass, composition, and size structures of phytoplankton, microzooplankton and mesozooplankton assemblages, measure microzooplankton growth and mesozooplankton reproduction rates, and measure grazing rates and prey preferences of heterotrophic protists and dominant species of mesozooplankton. They will also determine the fine scale vertical distribution of plankton, especially of fragile forms such as colonial phytoplankton, to identify thin layers of plankton/ particles in association with hydrographic features. Their collaborative study will explicitly address trophic linkages previously unexplored in this region of the subarctic. They hypothesize that changing ecosystem structure due to global warming, e.g. decrease in seasonal sea ice, will alter these trophic interactions, and thus the ultimate fates of algal production in this region. They plan to participate in each of the three annual cruises proposed for spring sea-ice conditions during the BEST field program. They will carry out a full set of analyses (standing stock determinations and rate measurements) at designated stations along transects within the BEST study area. Abundances and rate measures will be combined to determine relative microzooplankton and mesozooplankton grazing impacts. While the direct measurements and observations to be derived from this program will allow the principal investigators to describe the microzooplankton and mesozooplankton of the eastern Bering Sea shelf and their grazing impacts with a detail heretofore unavailable, the numbers they derive will also provide strong constraints on the ecosystem models to be developed as part of BEST. These models will serve as an important tool during the synthesis of the collective understanding derived by the BEST investigators.