Importance of Winter Upwelling to California Current Ecosystem Dynamics

冬季上升流对加州当前生态系统动态的重要性

• 批准号: 0929017
• 负责人: Bryan Black
• 金额: $ 22.37万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0929017&HistoricalAwards=false
• 关键词: Importance; Winter; Upwelling; California; Current

Climate variability on multiple temporal scales is increasingly recognized as a major factor influencing the structure, functioning, and productivity of the California Current Ecosystem. Yet despite long-term and integrative studies, a detailed understanding of climatic impacts is still lacking, compromising our abilities to interpret ecosystem variability over time and use that information to assess important concepts such as ecosystem health and resilience. Recent attempts to better establish the effects of climate have emphasized the relationship of reproductive and growth strategies of fish and seabirds to ecosystem phenology, particularly the timing of what is known as the "spring transition" from wintertime to spring upwelling conditions. However, there no clear definition of the spring transition has yet been established, and estimated spring transition dates do not adequately predict ecosystem productivity. Moreover, an increasing body of evidence suggests that ecosystem productivity is most sensitive to wintertime ocean variability prior to the traditional spring transition date. To address the importance of wintertime ocean conditions, a unique assemblage of rockfish and seabird time series relating to growth and reproductive success will be collated and analyzed with respect to environmental variability. All rockfish and seabird time series are multidecadal in length, annually resolved, and provide a view from the top by integrating ecosystem productivity after it has cascaded up through multiple lower trophic levels. This multi-species approach is particularly powerful considering that rockfish and seabird data independently reinforce one another. Pilot work shows that rockfish and seabird time series are strongly interrelated, and that these relationships are driven by shared sensitivities to wintertime ocean conditions, particularly February upwelling. Thus, the objectives of this study are to i) quantify the interrelationships among rockfish and seabird growth and reproduction time series, ii) identify the climatic variables, with an emphasis on the winter months, that correspond with covariability in rockfish and seabirds, and iii) evaluate the extent to which the abundance, distribution, and spatial organization of euphausiid crustaceans, a key prey item in the ecosystem, covary with seabirds, rockfish, and wintertime ocean conditions.This study will establish the times of year under which climate exerts the greatest influence on key upper-trophic level species, and provide leading biological and physical indicators of ecosystem productivity in the California Current Ecosystem. These biophysical indicators will be made available for integration into fisheries stock assessments and will also be of use for forecasting fisheries responses under various climatic scenarios. This information will also provide input to the California Current Integrated Ecosystem Assessment under development by NOAA-NMFS and others. In addition, the project will provide postdoctoral training in physical oceanography and undergraduate training in rockfish otolith growth-increment analysis.

多个时间尺度上的气候变化越来越被认为是影响加利福尼亚当前生态系统结构，功能和生产力的主要因素。然而，尽管长期和综合研究，仍然缺乏对气候影响的详细理解，这损害了我们解释随着时间的推移生态系统变异性的能力，并利用这些信息来评估重要概念，例如生态系统健康和韧性。最近试图更好地建立气候的影响的尝试强调了鱼类和海鸟与生态系统物候的生殖和生长策略的关系，尤其是从冬季到春季上升条件的“春季过渡”的时机。但是，尚未确定春季过渡的明确定义，估计的春季过渡日期不能充分预测生态系统的生产力。此外，越来越多的证据表明，在传统春季过渡日期之前，生态系统生产力对冬季海洋变异性最敏感。为了解决冬季海洋状况的重要性，将对与生长和生殖成功有关的岩石鱼类和海鸟时间序列的独特组合进行整理和分析，并在环境变异性方面进行分析。所有岩石和海鸟时间序列的长度都是多年代的，每年都可以解决，并通过在多个较低的营养水平上升级后，通过整合生态系统的生产率来从顶部提供视图。考虑到岩石鱼类和海鸟数据彼此独立增强，这种多种物种方法特别有力。飞行员工作表明，岩石和海鸟时间系列是密切相互关联的，这些关系是由对冬季海洋状况（尤其是2月上升趋势）的共同敏感性所驱动的。 Thus, the objectives of this study are to i) quantify the interrelationships among rockfish and seabird growth and reproduction time series, ii) identify the climatic variables, with an emphasis on the winter months, that correspond with covariability in rockfish and seabirds, and iii) evaluate the extent to which the abundance, distribution, and spatial organization of euphausiid crustaceans, a key prey item in the ecosystem,与海鸟，岩石和冬季海洋状况相关。这项研究将确定一年中的时代，气候对关键的上层营养水平物种产生最大的影响，并为加利福尼亚当前生态系统提供生态系统生产力的领先生物学和物理指标。这些生物物理指标将用于整合到渔业库存评估中，并且在各种气候场景下也将用于预测渔业反应。该信息还将为NOAA-NMF和其他人开发的加利福尼亚当前目前的综合生态系统评估提供意见。此外，该项目将提供物理海洋学和岩石鱼耳石生长灌溉分析的本科培训的博士后培训。