LTER: Scales of Variability in Ecosystem Dynamics and Production on the Changing Northeast U.S. Shelf (NES II)

LTER：变化中的美国东北部陆架生态系统动态和生产的变异规模 (NES II)

• 批准号: 2322676
• 负责人: Heidi Sosik
• 金额: $ 637.5万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2028-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2322676&HistoricalAwards=false
• 关键词: LTER; Scales; Variability; Ecosystem; Dynamics

The Northeast U.S. Shelf (NES) is the region of the Northwest Atlantic Ocean that overlies the continental shelf from North Carolina to Maine. The NES has a long history of intense human utilization and provides an array of ecosystem services including shipping, recreation, conservation, and energy development. The NES also comprises a seasonally dynamic and productive ecosystem, supporting renowned fisheries, whose integrity is critical to the health of the Northeast U.S. economy. The NES ecosystem’s productivity is fueled by planktonic organisms that interact with each other in complex food webs whose structure depends on environmental conditions (e.g., temperature, light, and nutrient levels). These conditions are rapidly changing because of climate-change-related warming and human utilization. For example, the NES is seeing the largest development of coastal wind farms in the U.S. to date. Phase II of the Northeast U.S. Shelf Long-Term Ecological Research program (NES-LTER II) advances our ability to predict how anthropogenic impacts will affect the dynamics of the shelf’s planktonic food webs and their ability to support the productivity of higher trophic levels, from fish to whales and humans. Because the NES is subject to long-term challenges that will impact many people, the project emphasizes an active education component for helping to train the next generation of marine scientists and outreach activities to increase public understanding of marine science and technology. The project team conducts education and outreach via three main components: (1) training and mentoring for early career researchers from undergraduates to postdoctoral researchers in LTER research; (2) an LTER Schoolyard program that engages middle and high school teachers and students; and (3) public outreach through targeted events, the project website, and social media channels.Patterns of ecosystem change over seasons to decades have been documented in the NES, but the key mechanisms linking changes in the physical environment, planktonic food webs, and higher trophic levels remain poorly understood. As a result, predictive capability is limited and management strategies are largely reactive. To address these needs, NES II is targeting a mechanistic understanding of how food web structure and function responds to environmental conditions, natural variability and human induced changes. NES II combines observations that provide regional-scale context, process cruises along a high gradient cross-shelf transect, high-frequency time series at an inner-shelf location, coupled biological-physical food web models, and targeted population models. In addition, the research team is investigating how community structure and trophic transfer are impacted by disturbances including (i) the increasing prevalence of heat waves, (ii) intrusions of offshore water associated with increasing instability in the Gulf Stream, and (iii) offshore wind farms now under construction on the NES. The long-term research plan is guided by the overarching science question: “How is climate change impacting the pelagic NES ecosystem and, in particular, affecting the relationship between compositional (e.g., species diversity and size structure) and aggregate (e.g., rates of primary production, and transfer of energy to higher trophic levels) variability?” The investigators are assessing the extent to which the NES ecosystem possesses a biodiversity reservoir that is resilient to dramatic changes in the environment and that will allow the ecosystem to maintain overall productivity.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.

美国东北部大陆架 (NES) 是西北大西洋的一个区域，覆盖从北卡罗来纳州到缅因州的大陆架，该地区有着悠久的人类密集利用历史，并提供一系列生态系统服务，包括航运、娱乐、保护、 NES 还包括一个季节性动态且富有成效的生态系统，支持着名的渔业，其完整性对于美国东北部经济的健康至关重要。 NES 生态系统的生产力由相互相互作用的浮游生物推动。复杂的食物网，其结构取决于环境条件（例如温度、光照和营养水平），由于与气候变化相关的变暖和人类利用，这些条件正在迅速变化，例如，沿海地区正在经历最大的发展。迄今为止，美国东北部大陆架长期生态研究计划 (NES-LTER II) 的第二阶段提高了我们预测人为影响将如何影响大陆架浮游食物网动态的能力。它们支持更高营养级（从鱼类到鲸鱼和人类）生产力的能力由于 NES 面临着影响许多人的长期挑战，因此该项目强调积极的教育内容，以帮助培训下一代海军陆战队。项目团队通过三个主要组成部分开展教育和宣传活动：(1) 对 LTER 研究中从本科生到博士后研究人员的早期职业研究人员进行培训和指导；吸引中学生参与的校园计划以及高中教师和学生；(3) 通过有针对性的活动、项目网站和社交媒体渠道进行公众宣传。生态系统随季节至几十年的变化模式已记录在 NES 中，但与物理变化相关的关键机制环境、浮游食物网和较高的营养水平仍然知之甚少，因此，预测能力有限，管理策略在很大程度上是被动的。为了满足这些需求，NES II 的目标是对食物网结构和功能如何响应进行机械理解。环境条件、自然NES II 结合了提供区域尺度背景的观测、沿高梯度跨大陆架横断面的过程巡航、大陆架内位置的高频时间序列、耦合的生物物理食物网模型和目标。此外，研究小组正在研究扰动对群落结构和营养转移的影响，这些扰动包括（i）热浪的日益流行，（ii）与墨西哥湾流日益不稳定相关的近海海水入侵，以及（ iii) 现在的海上风电场长期研究计划以总体科学问题为指导：“气候变化如何影响远洋NES生态系统，特别是影响组成（例如物种多样性和大小结构）和总体（例如，初级生产力和能量向更高营养级的转移）变异性？研究人员正在评估 NES 生态系统拥有的生物多样性库的程度，该库能够适应环境的剧烈变化，并允许该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。