EU-US ECOHAB. EC-NSF Cooperative Activity in Environmental Research: In Situ Holographic Measurements of Particle Distributions and Small Scale Turbulence in Thin Layers

欧盟-美国ECOHAB。

• 批准号: 0402792
• 负责人: Joseph Katz
• 金额: $ 73万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-01 至 2008-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0402792&HistoricalAwards=false
• 关键词: EU; US; ECOHAB.; EC; NSF

This project was submitted under the EU-US Cooperative Activity on the Ecology and Oceanography of Harmful Algae. The U.S. PIs will join colleagues from France, Ireland, Spain and UK to study the physics and biology of thin layers with concentrated Harmful Algal Bloom (HAB). Serious problems in Europe are caused by contamination of farmed shellfish with Diarrheic Shellfish Poisoning (DSP) toxins produced by the dinoflagellate genus Dinophysis. The existence of thin layers with high Dinophysis concentration has come to light recently, but the information is sporadic because the layers can be present at any depth, and due to sampling difficulties with standard instruments. In the case of Dinophysis, the concentration does not depend solely on nutrition, but also on interactions between physics, life cycle and behavior. This study will determine the hydrodynamic (e.g. local flow structure, turbulence, stratification, small gyres and pycnoclines), biological (e.g. growth, nutrition and mortality) and chemical environment leading to the build up, maintenance and population dynamics of Dinophysis in thin layers. The field tests will take place under a variety of hydrodynamic regimes in the Rias of Galicia (NWSpain), the estuarine plume zones of the Atlantic coast of France, and in the bays of southwestern Ireland. All are shellfish production areas with history of harvest closures due to contamination with DSP toxins. The Johns Hopkins group will focus on small-scale biophysical and particle-particle interactions. By deploying a submersible holocamera, augmented with a digital holographic cinematography, they will observe and measure processes and interactions occurring at the critical scales of 10 mm to 10 cm. Automated data analysis tools will enable the investigators to process a large database under various conditions that will be used for parameterizing the behavior of Dinophysis. The results will include: i. The spatial and size distributions of different classes of particles. Particles larger than 10 mm are detected, and shapes can be defined in particles larger than 30 mm. ii. The nearest neighbor distance (NNS) within the same species, and between species, including predators and prey; iii. The instantaneous 3-D velocity distributions within the sample volume, which is used for calculating the local velocity, strain rate, vorticity, dissipation rate and turbulence intensity; iv. The swimming behavior (speed, trajectory, direction) of Dinophysis in its local environment; v. Direct observations on behavior, feeding and grazing of Dinophysis; vi. Conditional statistics of concentration, NNS and behavior based on local physical and biological parameters;Intellectual Merit: Progress in understanding of population dynamics of different phytoplankton species, including Dinophysis, requires detailed knowledge of their in-situ concentrations, behavior, and biophysical interactions. This project will deploy a new but proven/developed technology in the ocean in order to obtain detailed and unique insight on the interaction of dinoflagellates with their local biophysical environments. The results will illuminate processes affecting the formation and maintenance of thin layers containing Dinophysis. Broader Impacts. Socio-Economic Issues: HAB adversely affect health, tourism, fisheries and food production in the coastal ocean, causing closure of fisheries, illness and even death. This project will obtain essential information to develop such understanding of the importance of bio-physical mechanisms in the formation of some HABs. Education of future Scientists: Studies of biophysical interactions in the ocean require background in biology, fluid mechanics, and instrumentation. This project will support one such student in an interdisciplinary training program.

该项目是根据欧盟 - 美国关于有害藻类生态和海洋学的合作活动提交的。美国PI将与来自法国，爱尔兰，西班牙和英国的同事一起研究具有浓缩有害藻华（HAB）的薄层的物理和生物学。欧洲的严重问题是由于鞭毛鞭毛属Dinophysy产生的腹泻贝类中毒（DSP）毒素的耕种贝类污染引起的。最近发现了具有高饮食浓度的薄层的存在，但是信息是零星的，因为这些层可以在任何深度存在，并且由于标准仪器的抽样困难。在Dinophysy的情况下，浓度不仅取决于营养，还取决于物理，生命周期和行为之间的相互作用。这项研究将确定流体动力学（例如局部流动结构，湍流，分层，小回旋和pycnoclines），生物学（例如生长，营养和死亡率）以及化学环境，从而导致薄层中二层人群的维持和种群动态。现场测试将在加利西亚（NWSpain），法国大西洋海岸的河口羽状区以及爱尔兰西南海湾的各种流体动力学政权下进行。所有这些都是由于对DSP毒素污染而导致收获史的贝类生产区域。约翰·霍普金斯（Johns Hopkins）组将集中于小规模的生物物理和粒子粒子相互作用。通过部署可使用数字全息摄影的潜水性全部，他们将观察和测量在10 mm至10 cm的临界尺度上发生的过程和相互作用。自动数据分析工具将使研究人员能够在各种条件下处理一个大型数据库，以参数化Dinophysis行为。结果将包括：i。不同类别颗粒的空间和大小分布。检测到大于10 mm的颗粒，并且可以在大于30 mm的颗粒中定义形状。 ii。在同一物种中以及包括捕食者和猎物在内的物种之间的最近的邻居距离（NN）； iii。样品体积内的瞬时3-D速度分布，用于计算局部速度，应变速率，涡度，耗散速率和湍流强度； iv。 Dinophsy在当地环境中的游泳行为（速度，轨迹，方向）； v。对行为，喂养和放牧的直接观察； vi。基于局部物理和生物学参数的浓度，NNS和行为的有条件统计；智力优点：了解不同浮游植物物种种群动态的进展，包括Dinophysis，需要详细了解其原位浓度，行为，行为和生物物理相互作用。该项目将在海洋中部署一种新的但已验证的技术，以便获得有关鞭毛藻与当地生物物理环境相互作用的详细和独特的见解。结果将阐明影响含有Dinophysy的薄层的形成和维护的过程。更广泛的影响。社会经济问题：HAB在沿海海洋中不利影响健康，旅游业，渔业和粮食生产，导致渔业，疾病甚至死亡的关闭。该项目将获得基本信息，以发展对生物物理机制在某些HAB形成中的重要性的理解。对未来科学家的教育：海洋生物物理相互作用的研究需要生物学，流体力学和仪器的背景。该项目将在跨学科培训计划中为一个这样的学生提供支持。