OCE-PRF The ecological and economic consequences of coastal hypoxia: a case study using a novel in situ benthic observing system, Wormcam

OCE-PRF 沿海缺氧的生态和经济后果：使用新型原位海底观测系统 Wormcam 进行案例研究

• 批准号: 1324294
• 金额: $ 17万
• 依托单位: Sturdivant Samuel K
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1324294&HistoricalAwards=false
• 关键词: OCE; PRF; ecological; economic; consequences

Overview: In this project, the fellow will conduct a study of the dynamics of community structure of coastal benthic systems, in situ, and under hypoxic conditions, the role of physiological adaptations in maintaining benthic services and functions, and the economic cost of hypoxia. This work will be undertaken under the mentorship of Professor Cindy Lee Van Dover at the Marine Laboratory of the Nicholas School of the Environment, Duke University. Coastal hypoxia can have negative consequences on benthic community structure and function. While the effects of hypoxia on benthic community structure are well understood, less well known are impacts to community function. At the onset of hypoxia, mobile fauna are displaced, and, as the severity and duration of hypoxia increase, community structure of non-mobile infauna degrades (i.e., loss of biodiversity, biomass, activity). Impacts of hypoxia can have ecosystem-level consequences, including reductions in benthic fisheries that depend on infauna for their nutrition (e.g., demersal fish and epibenthic crustacean predators); degradation of the infauna community also reduces bioturbation rates, altering rates of biogenic remineralization of nutrients and pollutant sequestration. Intellectual Merit: This study will take advantage of comparative systems that experience sustained (Chesapeake Bay, VA) and intermittent (Neuse River, NC) seasonal hypoxia to answer the following questions: 1) What is the relationship between hypoxia and bioturbation rates under sustained and intermittent conditions of hypoxia? This question will be addressed through 12-months of benthic observations in two systems using time-series (hourly) sediment profile imaging (SPI) and environmental sensing systems, together with monthly replicate sampling for spatial characterization of bioturbation rates (sediment profiles) and community structure (sediment grabs). Study locations will be chosen based on the history of hypoxia in each system, using data from the Chesapeake Bay Benthic Monitoring and Neuse River Estuary Modeling and Monitoring Programs of the Chesapeake Bay Program and University of North Carolina Chapel Hill's Institute of Marine Science, respectively. 2) What is the relationship between hypoxia and physiological response of key system organisms? This relationship will be examined using respirometry and gene expression methodologies in two benthic polychaete species, and will test the hypothesis that there are significant differences in response between organisms cultured from Chesapeake Bay and the Neuse River. Cultured polychaetes from each system will be put through hypoxia trials using stop-flow respirometry to determine metabolic rate, O2 extraction, and the O2 saturation level that induces mortality. Subsamples of worms will be removed and frozen at intervals in the hypoxia trials for subsequent Restriction site Associated DNA sequencing to survey for differential gene expression. 3) What is the economic cost of coastal hypoxia. The fellow will develop a bioeconomic model that explores the economic costs of hypoxia in Chesapeake Bay by relating hypoxic affects to a benthic fishery (i.e. blue crabs), and compare those results with economic valuations of hypoxia previously conducted in the Neuse River. Broader Impacts: Research results will be disseminated in the scientific literature and will provide new knowledge useful to coastal environmental managers. The fellow will expand efforts to broaden the participation of minorities in ocean science through mentoring programs at Duke University, in the ASLO Multicultural Program, and in the annual Youth Education Summit of the National Association of Black Scuba Divers, which targets grade school minorities with an interest in ocean science.

概述：在这个项目中，该研究员将研究在原地和缺氧条件下沿海底栖系统群落结构的动态、生理适应在维持底栖服务和功能方面的作用以及缺氧的经济代价。这项工作将在杜克大学尼古拉斯环境学院海洋实验室的Cindy Lee货车多佛教授的指导下进行。沿海缺氧可对底栖生物群落结构和功能产生不利影响。虽然低氧对底栖生物群落结构的影响已广为人知，但对群落功能的影响却鲜为人知。在缺氧开始时，移动的动物群被取代，并且随着缺氧的严重程度和持续时间的增加，非移动的底栖动物群的群落结构退化（即，生物多样性、生物量、活动的丧失）。缺氧的影响可产生生态系统一级的后果，包括依赖底栖动物提供营养的底栖渔业减少（例如，底栖鱼类和底栖甲壳类食肉动物）;底栖动物群落的退化也降低了生物扰动率，改变了营养物的生物矿化率和污染物固存率。智力优势：本研究将利用经历持续（切萨皮克湾，弗吉尼亚州）和间歇性（纽斯河，北卡罗来纳州）季节性缺氧的比较系统来回答以下问题：1）在持续和间歇性缺氧条件下，缺氧和生物扰动率之间的关系是什么？这个问题将通过在两个系统中使用时间序列（每小时）沉积物剖面成像和环境传感系统进行为期12个月的海底观测来解决，同时每月进行重复采样，以确定生物扰动率（沉积物剖面）和群落结构（沉积物抓取）的空间特征。研究地点将根据每个系统的缺氧历史选择，分别使用来自切萨皮克湾计划和北卡罗来纳州查佩尔山海洋科学研究所的切萨皮克湾底栖监测和纽斯河口建模和监测计划的数据。2)缺氧与关键系统生物的生理反应有什么关系？这种关系将使用呼吸测定法和基因表达方法在两个底栖多毛类物种，并将测试的假设，有显着差异的反应之间培养的生物从切萨皮克湾和纽斯河。将使用停流呼吸测定法对来自每个系统的培养多毛纲动物进行缺氧试验，以确定代谢率、O2提取和诱导死亡的O2饱和度水平。在低氧试验中，将每隔一段时间取出蠕虫子样品并冷冻，用于随后的限制性位点相关DNA测序，以调查差异基因表达。3)沿海缺氧的经济代价是什么？该研究员将开发一个生物经济模型，探讨缺氧的经济成本在切萨皮克湾缺氧的影响，底栖渔业（即蓝蟹），并比较这些结果与缺氧的经济估值以前在纽斯河进行。更广泛的影响：研究结果将在科学文献中传播，并将为沿海环境管理人员提供有用的新知识。该研究员将通过杜克大学的辅导方案、ASLO多元文化方案和全国黑人水肺潜水员协会年度青年教育峰会，扩大少数群体对海洋科学的参与，该峰会的目标是对海洋科学感兴趣的小学少数群体。