GLOBEC 2000 -- A long-Term Observation Program Using Natural Stable Isotope Abundance for Detecting Coastal Gulf of Alaska Zooplankton Source Fluctuations in Fishes

GLOBEC 2000——利用天然稳定同位素丰度检测阿拉斯加湾沿海鱼类浮游动物源波动的长期观测计划

• 批准号: 0114560
• 负责人: Thomas Kline
• 金额: $ 65.01万
• 依托单位: Prince William Sound Science Center
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-01 至 2006-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0114560&HistoricalAwards=false
• 关键词: GLOBEC; 2000; long; Term; Observation

Decadal-scale changes in the production cycles of the sub-Arctic Pacific Ocean have been conjectured to effect population changes in fishes via their zooplankton forage base. Zooplankton populations occurring near the Gulf of Alaska continental shelf break appear to undergo dramatic oscillations in abundance over decadal time scales. These consist principally of inter-zonal (because life-history stages span shallow- and deep-water zones) zooplankton (primarily Neocalanus spp. copepods) stocks that are driven onto the shelf providing the ecosystem with an important forage base.The data arising from this project will enable the assessment of seasonal (during 2001 and 2003) and inter-annual 15N/14N and 13C/12C variability of large-bodied zooplankton (primarily Neocalanus) across the Gulf of Alaska continental shelf during their peak occurrence in spring and summer each year, that will be matched to analogous measurements for juvenile pink salmon and other fishes. These data will be used to isotopically characterize coastal and oceanic (offshore) organic carbon sources and their utilization by fishes. Isotopic shifts in fishes and diapausing copepods are expected to shift in synchrony varying proportionately with the intensity of cross-shelf transport. This project will augment and complement existing and continuing core LTOP observations being made along the Seward Line transect (GAK1 to GAK13) and select stations near and in Prince William Sound. Samples that were acquired by the P.I. from fall 1997 through summer 2000 on pilot LTOP project (Weingartner, P.I.) cruises will be analyzed for 13C/12C and 15N/14N content as part of this project during FY2001 and FY2002. Additional samples will be collected and analyzed as part of this project from 2001 through 2005. The data will also be used to validate the tacit assumption in NEP GLOBEC retrospective studies that 15N/14N values of lower food chain biota are constant so that so that changing values can be interpreted to reflect varying food chain length or salmon run size.

亚北极太平洋生产周期的十年尺度变化已被证明通过浮游动物饲料基地影响鱼类种群的变化。发生在阿拉斯加湾大陆架断裂附近的浮游动物种群在十年时间尺度上似乎经历了剧烈的丰度振荡。这些主要包括带间（因为生活史阶段跨越浅水区和深水区）浮游动物（主要是新哲水蚤属）。该项目产生的数据将使人们能够评估季节性的鱼类（桡足类）种群，大型浮游动物15 N/14 N和13 C/12 C的年际变化（主要是新哲水蚤）在每年春季和夏季的高峰期穿越阿拉斯加湾大陆架，这将与幼粉红鲑鱼和其他鱼类的类似测量相匹配。这些数据将用于对沿海和海洋（近海）有机碳源及其被鱼类利用的情况进行同位素表征。预计鱼类和滞育桡足类的同位素变化将与跨大陆架运输的强度成比例地同步变化。 该项目将增强和补充沿着苏厄德线样带（GAK 1至GAK 13）进行的现有和持续的核心LTOP观测，并选择威廉王子湾附近和内的台站。从私家侦探那里得到的样本。从1997年秋季到2000年夏季，LTOP试点项目（Weingartner，P.I.）在2001和2002财政年度期间，作为该项目的一部分，将对13 C/12 C和15 N/14 N含量进行分析。从2001年到2005年，作为该项目的一部分，将收集和分析更多的样本。 这些数据还将用于验证NEP GLOBEC回顾性研究中的默认假设，即较低食物链生物群的15 N/14 N值是恒定的，因此可以解释变化的值以反映不同的食物链长度或鲑鱼运行大小。