Collaborative Research: Metabolic habitat barriers imposed on tropical diel vertical migrators

合作研究：对热带昼夜垂直迁徙者施加的代谢栖息地障碍

• 批准号: 2127299
• 负责人: Amy Maas
• 金额: $ 29.77万
• 依托单位: Bermuda Institute of Ocean Sciences (BIOS), Inc.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2127299&HistoricalAwards=false
• 关键词: Collaborative; Research; Metabolic; habitat; barriers

This project is seeking to define physiologically-accessible habitat for animals faced with changing ocean conditions. Many oceanic animals migrate daily from warm, oxygenated surface waters at night to deep, cold and hypoxic waters during the daytime, and these migrations play critical roles in oceanic ecology and biogeochemical cycles. Over their depth ranges, migrators face very different ecological and environmental demands that may lead to unique traits that in turn, influence how they respond to a warming ocean where oxygen minimum zones are also expanding. This study is combining ecological and physiological approaches during two expeditions to the Gulf of California. The investigators are measuring metabolic traits in a diverse suite of ocean animals that exhibit vertical migration to determine possible roles of oxygen and temperature in triggering changes in vertical and latitudinal distribution. They are also measuring species distributions in relation to environmental oxygen and temperature to determine ecologically-relevant thresholds of environmental tolerance. The project involves training and experiential learning for graduate and undergraduate students. In addition, engagement with educational experts and artists will generate media and lesson plans to support STEM education and Next Generation Science Standards. These activities leverage the Bermuda Institute of Ocean Sciences’ Databytes and Mid-Atlantic Robotics IN Education (MARINE) programs, designed to improve ocean literacy and technological fluency and targeting students from groups traditionally underrepresented in science. Project products also include a new level for a video game that introduces the concepts of how oxygen minimum zones influence animal distribution.Climate change is driving poleward shifts in the distributions of marine animals. These shifting edges of the range of species habitats are often interpreted as a manifestation of oxygen limitation that is presumed to occur at high water temperatures due to a mismatch between physiological oxygen supply and thermodynamically-driven oxygen demand. However, recent work by the investigators suggests that oxygen supply has evolved to meet demand regardless of temperature. These opposing views predict very different thermal thresholds for range expansion. In this study, the investigators are employing a relationship between metabolic traits to infer a unique temperature sensitivity in tropical diel vertical migrators and to map their metabolically-available habitat in the Eastern Pacific. Specifically, the investigators propose that oxygen supply does not limit metabolism in tropical migrators, even in the oxygen minimum zone. Instead, they contend that the active metabolic rate for tropical migrators is highly sensitive to temperature, and that this creates a barrier to range expansion where the aerobic scope for growth and reproduction is insufficient in cold waters. This temperature sensitivity will also allow migrators to expand poleward to newly available habitat following modest warming, rather than simply being extirpated from their native tropical habitat by excess warming. This hypothesis, if supported, would transform our mechanistic understanding of species’ responses to climate change, amend our predictions of range expansion, and modify our assessment of migrator contributions to oceanic biogeochemical cycles in a warmer future ocean.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该项目正在旨在为面临不断变化的海洋状况的动物定义物理上可接近的栖息地。许多海洋动物每天从夜间温暖，含氧的地表水迁移到白天的深，冷和低氧水域，这些迁移在海洋生态学和生物地球化学周期中起着至关重要的作用。在其深度范围内，迁移者面临着非常不同的生态和环境需求，这可能导致独特的特征，从而影响他们对氧气最小区域也在扩大的温暖海洋的反应。这项研究正在与加利福尼亚湾进行两次探险期间结合生态和物理方法。研究人员正在测量一组海洋动物套件中的代谢特征，这些特征暴露了垂直迁移，以确定氧气和温度在触发垂直和纬度分布变化中的可能作用。他们还在测量与环境氧和温度有关的物种分布，以确定环境耐受性与生态相关的阈值。该项目涉及研究生和本科生的培训和专家学习。此外，与教育专家和艺术家的互动将制定媒体和课程计划，以支持STEM教育和下一代科学标准。这些活动利用了百慕大海洋科学研究所的数据素和教育中大西洋中部机器人技术（旨在提高海洋素养和技术流利性，并针对传统上代表性不足的群体的学生。项目产品还包括一个视频游戏的新级别，该游戏介绍了氧最小区域如何影响动物分布的概念。气候变化正在推动海洋动物分布的极点变化。这些物种栖息地范围的转移边缘通常被解释为氧限制的表现，由于物理氧供应与热力学驱动的氧气需求之间的不匹配，这表明是在高水温下发生的。但是，研究人员最近的工作表明，无论温度如何，氧气供应已经发展为满足需求。这些相反的观点预测了范围扩展的非常不同的热阈值。在这项研究中，研究人员正在采用代谢性状之间的关系来推断热带模具垂直迁移者的独特温度敏感性，并在东太平洋绘制其代谢可用的栖息地。具体而言，研究人员建议即使在氧最小区域中，氧气供应也不会限制热带迁移者的代谢。取而代之的是，他们认为，热带迁移器的主动代谢率对温度高度敏感，这为范围扩展造成了障碍，在冷水中，有氧增长和繁殖的范围不足。这种温度敏感性还将使迁移者在适度的变暖后将迁移者扩展到新近可用的栖息地，而不是通过过量的变暖从其天然的热带栖息地中消除。如果得到支持，该假设将改变我们对物种对气候变化的反应的机械理解，修改了我们对范围扩展的预测，并修改了我们对迁移者对海洋生物地球化学循环的贡献的评估，这是NSF的法定任务，反映了NSF的法定任务，并通过使用基金会的范围和广泛的评估来进行评估，并通过评估了支持。