GLOBEC: Applying Molecular Organic Tracers to Determine Age Structure, Nutritional Status and Possible Trophic Transfer in Euphausiids Euphausia Pacifica and Thysanoessa Spinifer

这项研究项目研究了GLOBEC的两个主要目标生物--龙虾Euphausiid diapacphaa和棘胸甲Thysanoessa spinifera的种群年龄结构和营养状况。利用新陈代谢生化标记物(脂褐素)量化方面的最新进展，研究人员将确定加州现行系统中两种浮游动物的种群年龄结构，特别是在俄勒冈州中部外按物理分区分隔的种群。对相同种群亚群的脂肪分析将提供营养状况和喂食史的衡量标准。与当前的全球鲑鱼长期监测计划(L-TOP)相结合的采样将提供每个种群的身体结构信息，以及季节性和年际时间尺度上的营养状况衡量标准，以更好地预测它们的生产、补充，从而对鲑鱼的生长和生存具有重要意义。研究目标包括：1.应用最新的生物化学方法测定太平洋真甲虫和棘突足甲种群的年龄结构，以及中尺度动态对队列种群季节性和年际维持或中断的影响。使用脂类检查陆架水域物理分区对幼体和成体的营养状况和生殖潜力的影响；将使用季节性和年际措施，提供有关营养状况变化对随后的补充和丰度变化的潜在影响的信息。将年龄结构信息与脂类分析相结合，以了解营养状况在季节和年际时间尺度上对太平洋毛虫和刺毛虫野外种群年龄结构的影响。调查浮游动物和其他浮游动物的个体脂肪作为食物的分子标记，以及它们作为向捕食者营养转移的标记的可能性。

This research project addresses the population age structure and nutritional status of the two primary target organisms for GLOBEC, the euphausiids Euphausii diapacifica and Thysanoessa spinifera. Using recent advances in quantifying biochemical markers of metabolism (lipofuscins), the researchers will determine the population age structure of both zooplankton in the California current system with particular emphasis on populations separated by physical zonation off the central Oregon. Lipid analysis in subsets of the same populations will provide a measure of nutritional status and feeding history. Sampling in conjunction with the current GLOBEC long term monitoring program (L-TOP) will provide information on physical structuring of each population together with measures of nutritional status over seasonal and interannual time scales to better predict their production, recruitment and thus importance in salmonid growth and survival. The research objectives include:1. Application of recent advances in biochemical methods to determine the age structure in populations of the two major euphausiid species Euphausia pacifica and Thysanoessa spinifera and the effects of mesoscale dynamics on maintenance or disruption of cohort populations seasonally and interannually.2. Examine the effects of physical zonation in shelf waters on the nutritional status and thus reproductive potential in juvenile and adults euphausiids (and eggs) using lipid classes; seasonal and interannual measures will be used provide information on the potential effects of changing nutritional status on subsequent recruitment and variations in abundance.3. To combine age structure information with lipid analysis in sets of the same individuals to understand the impact of nutritional status on age structure in field populations of E. pacifica and T. spinifera over seasonal and interannual time scales.4. To investigate individual lipids in euphausiids and other zooplankton as molecular markers of diet and their potential as markers of trophic transfer to their predators.