RUI: Collaborative Research: Microscale interactions of foundation species with their fluid environment: biological feedbacks alter ecological interactions of mussels

RUI：合作研究：基础物种与其流体环境的微观相互作用：生物反馈改变贻贝的生态相互作用

• 批准号: 2050129
• 负责人: Michael Nishizaki
• 金额: $ 9.79万
• 依托单位: Carleton College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-02-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2050129&HistoricalAwards=false
• 关键词: RUI; Collaborative; Research; Microscale; interactions

The project investigates how the metabolic activity of dense aggregations of marine organisms alter the water chemistry of their interstitial spaces, and how these microscale alterations feedback to affect the organisms’ interactions in coastal ecosystems. The research team focuses on bivalve mussels, foundation species that form dense ‘beds’ typically known for facilitating other species by ameliorating harsh flow conditions. This ability can become a liability, however, if flow is not sufficient to flush the interstitial spaces and steep, metabolically-driven concentration gradients develop. The research evaluates whether corrosive chemical microclimates (such as low oxygen or low pH) are most extreme in low flow, high temperature conditions, especially for dense aggregations of mussels with large biomass and/or high respiration rates, and if they negatively impact mussel beds and the diverse biological communities they support. The research addresses a global societal concern, the impact of anthropogenic climate change on coastal marine ecosystems, and has potential applications to aquaculture and biofouling industries by informing adaptation strategies to “future-proof” mussel farms in the face of climate change and improved antifouling practices for ships, moorings, and industrial cooling systems. The project forges new collaborations with investigators from three campuses and integrates research and education through interdisciplinary training of a diverse group of graduate, undergraduate and high school students. STEM education and environmental stewardship is promoted by the development of a K-12 level science curriculum module and a hand’s-on public exhibit of bivalve biology at a local shellfish farm. Research findings are disseminated in a variety of forums, including peer-reviewed scientific publications and research presentations at regional, national and international meetings.The research team develops a framework that links environmental conditions measured at a coarse scale (100m-100km; e.g., most environmental observatories) and ecological processes at the organismal scale (1 cm – 10 m). Specifically, the project investigates how aggregations of foundation species impact flow through interstitial spaces, and how this ultimately impacts water chemistry immediately adjacent to the organisms. The research focuses on mytilid mussels, with the expectation that the aggregation alters the flow and chemical transport in two ways, one by creating a physical resistance, which reduces the exchange, and the other by enhancing the exchange due to their incurrent/excurrent pumping. These metabolically-driven feedbacks are expected to be strongest in densely packed, high biomass aggregations and under certain ambient environmental conditions, namely low flow and elevated temperature, and can lead to a range of negative ecological impacts that could not be predicted directly from coarse scale measures of ambient seawater chemistry or temperature. The team develops computational fluid dynamic (CFD) models to predict interstitial flows and concentration gradients of dissolved oxygen and pH within mussel beds. The CFD model incorporates mussel behavior and physiological activity (filtration, gaping, respiration) based on published values as well as new empirical work. Model predictions are compared to flow and concentration gradients measured in mussel aggregations in the laboratory and field. Finally, the team conducts several short-term experiments to quantify some of the potential negative ecological impacts of corrosive interstitial water chemistry on mussel aggregations, such as reduced growth, increased dislodgement, increased predation risk, and reduced biodiversity. Because the model is based on fluid dynamic principles and functional traits, the framework is readily adaptable to other species that form dense assemblages, thereby providing a useful tool for predicting the ability of foundation species to persist and provide desirable ecosystem services under current and future multidimensional climate scenarios.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.

该项目调查密集海洋生物聚集体的代谢活动如何改变其间隙空间的水化学，以及这些微尺度变化如何反馈影响沿海生态系统中生物的相互作用。研究小组将重点放在双壳贻贝上，这是一种基础物种，形成了密集的“床”，通常通过改善恶劣的流动条件为其他物种提供便利。然而，如果血流不足以冲洗间隙，并形成陡峭的新陈代谢驱动的浓度梯度，这种能力可能会成为一种不利因素。这项研究评估腐蚀性化学微气候(如低氧或低pH)在低流量、高温条件下是否最极端，特别是对于生物量大和/或呼吸速率高的贻贝密集聚集地，以及它们是否对贻贝床和它们所支持的多样化生物群落产生负面影响。这项研究解决了全球社会关注的问题，即人为气候变化对沿海海洋生态系统的影响，并通过在面对气候变化和改进船舶、系泊和工业冷却系统的防污实践，为“不受未来影响的”贻贝养殖场提供适应战略，从而潜在地应用于水产养殖和生物污损行业。该项目与来自三个校区的研究人员建立了新的合作关系，并通过对不同的研究生、本科生和高中生进行跨学科培训，整合了研究和教育。通过开发K-12级别的科学课程模块和在当地贝类养殖场举办双壳类生物学亲身公共展览，促进了茎教育和环境管理。研究结果在各种论坛上传播，包括同行评议的科学出版物和在区域、国家和国际会议上的研究报告。研究小组开发了一个框架，将粗略尺度(100米-100公里；例如大多数环境观测站)测量的环境条件与生物尺度(1厘米-10米)的生态过程联系起来。具体地说，该项目调查了基础物种的聚集如何影响通过间隙空间的流动，以及这最终如何影响紧挨着生物体的水化学。这项研究的重点是贻贝，期望这种聚集通过两种方式改变流动和化学运输，一种是通过产生物理阻力来减少交换，另一种是通过增加流入/流出泵送的交换来增强交换。这些由新陈代谢驱动的反馈预计在密集、高生物量聚集和某些环境环境条件下(即低流量和高温度)最强，并可能导致一系列负面生态影响，而这些负面生态影响无法通过环境海水化学或温度的粗略尺度测量直接预测。该团队开发了计算流体动力学(CFD)模型来预测贻贝床内的间质流动以及溶解氧和pH的浓度梯度。CFD模型结合了贻贝的行为和生理活动(过滤、张口、呼吸)，基于已公布的数值和新的经验工作。将模型预测与在实验室和田间测量的贻贝聚集物中测量的流动和浓度梯度进行比较。最后，该团队进行了几个短期实验，以量化腐蚀性间隙水化学对贻贝聚集体的一些潜在的负面生态影响，如生长减慢、移位增加、捕食风险增加和生物多样性减少。由于该模型基于流体动力学原理和功能特征，该框架很容易适应形成密集群落的其他物种，从而为预测基础物种在当前和未来多维气候情景下持续存在并提供理想的生态系统服务的能力提供了有用的工具。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。