RUI: River and sediment-modulated stress in planktonic and early settlement Mya arenaria

RUI：浮游生物和早期定居的河流和沉积物调节的胁迫

• 批准号: 0961825
• 负责人: Mark Green
• 金额: $ 50.02万
• 依托单位: Saint Joseph's College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2014-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0961825&HistoricalAwards=false
• 关键词: RUI; River; sediment; modulated; stress

Estuaries are productive, complex and have great economic value by virtue of their fisheries, ecosystem services and recreation potential. They are typically less buffered to acid than open oceans due to the combined effects of acid production during heterotrophy and acidic inputs from both land and atmosphere. Within estuaries, it is important to understand how varying acid burdens impact living resources, particularly those that provide ecosystem services and/or generate income as fisheries. The bivalve Mya arenaria, the focal species of this proposed research, is one such resource that sustains a valuable coastal fishery while providing service via its filtration capacity. Because Mya shells are constructed from a relatively soluble form of calcium carbonate (aragonite), and the clams often inhabit eutrophic waters, they may be particularly vulnerable as pH declines. Planktonic larvae and benthic juveniles are critical life stages -- even small reductions in theier abundances could substantially decrease adult populations. This proposed research addresses four distinct hypotheses concerning the roles of riverine and sediment interactions on the viability of larval and juvenile Mya. Research activities include the following. 1. Fieldwork will evaluate the spatial and seasonal changes in aragonite saturation state within the Kennebec River Estuary and Casco Bay. Seasonal sampling will be coupled with high-frequency sampling during the annual Mya spawn to observe and document the effect of lowered aragonite saturation state on the health status of larval Mya. 2. Using larval Mya, laboratory experiments will mimic the aragonite saturation state observed in Casco Bay during the high-frequency cruises. Metamorphic change (veligers, pediveligers, and metamorphosed juveniles), growth rate, and survivorship of Mya will be evaluated as a function of aragonite saturation state. 3. Spatially intensive daily cohort monitoring of the intertidal mud flats in Falmouth, Maine, will establish the link between changes in abundance of settling juveniles and aragonite saturation state during the period of Mya set. Cohort monitoring of settling Mya will be examined in reference to sediment pH and aragonite saturation state in nearby deposits to ascertain if sediment saturation state is a primary settlement cue for transitioning larvae. 4. A diagnostic model will be developed for the shellfish management community that can be used to detect aragonite saturation state of the water column. The model would run on routine oceanographic measurements (salinity, temperature, oxygen and chlorophyll fluorescence). Intellectual merit of study: The chemical consequences of increasing atmospheric CO2 and resulting hydrolysis of carbonic acid is well understood and resultant ocean acidification has been accurately predicted with the current generation of global circulation models. These predictions have accelerated research into the effects of ocean acidification on marine organisms, particularly those with CaCO3 exoskeletons. Estuarine waters are far less buffered than oceans, are subject to a variety of acid loadings, and are quite possibly acidifying at a faster rate than the open ocean. Yet, these regions have been largely ignored in 'acidification' research. Effects of acidification on calcifying organisms are similar regardless of whether of acid origin -- atmospheric exchange, net heterotrophy, or discharge of acidic river water. Likewise, each of these acid fluxes is being perturbed via anthropogenic activity (e.g. fossil fuel use, deforestation, agriculture). The proposed research will further understanding of the combined and cumulative impacts of varied acid burdens on calcifying organisms in coastal waters. Broader impacts of study: Saint Joseph's College of Maine is an undergraduate institution with many potential opportunities to introduce students to the excitement of scientific research and discovery. This project will have special significance to the 70% of women that make up the student body at Saint Joseph's College, many of whom will experience research science for the first time. The immersion of students into research will be modeled after other sponsored research at SJC, resulting in a new marine science major, in over 35 SJC undergraduates attending and/or presenting research results at national/international conferences (12 as co-authors), and in 4 students co-authoring recent papers for publication.

河口多产、复杂，并因其渔业、生态系统服务和娱乐潜力而具有巨大的经济价值。由于异养过程中产生的酸以及来自陆地和大气的酸输入的综合影响，它们通常比开阔海洋对酸的缓冲较少。在河口内，重要的是了解不同的酸负荷如何影响生物资源，特别是那些提供生态系统服务和/或作为渔业产生收入的资源。这项拟议研究的重点物种双壳类Mya arenaria就是这样一种资源，通过其过滤能力维持宝贵的沿海渔业，同时提供服务。由于MYA贝壳是由一种相对可溶的碳酸钙(文石)构成的，而文蛤经常生活在富营养化的水域，随着pH的下降，它们可能特别容易受到伤害。浮游幼虫和底栖幼虫是关键的生活期--即使它们的丰度略有减少，也可能大幅减少成虫数量。这项拟议的研究提出了四个不同的假设，即河流和沉积物相互作用对幼体和幼体Mya生存的作用。研究活动包括以下内容。1.实地调查将评估肯纳贝克河口和卡斯科海湾文石饱和状态的空间和季节变化。在一年一度的Mya产卵期间，将结合季节性采样和高频采样，观察和记录降低文石饱和状态对Mya幼虫健康状况的影响。2.使用幼虫Mya，实验室实验将模拟高频巡航期间在卡斯科海湾观察到的文石饱和状态。Mya的变质变化(幼虫、幼虫和幼虫)、生长速度和存活率将作为文石饱和状态的函数进行评估。3.对缅因州法尔茅斯潮间带泥滩进行空间密集的每日队列监测，将建立Mya Set期间定居幼体丰度的变化与文石饱和状态之间的联系。将参照附近沉积物中的沉积物pH和文石饱和状态检查沉淀物Mya的队列监测，以确定沉积物饱和状态是否是过渡幼虫的主要定居线索。4.将为贝类管理界开发一个诊断模型，可用于检测水柱的文石饱和状态。该模型将根据常规的海洋测量(盐度、温度、氧气和叶绿素荧光)运行。研究的智慧价值：人们很好地了解了大气中二氧化碳增加和由此导致的碳酸水解的化学后果，并利用当前一代全球环流模型准确地预测了由此产生的海洋酸化。这些预测加速了对海洋酸化对海洋生物的影响的研究，特别是那些具有CaCO3外骨骼的海洋生物。河口水域的缓冲比海洋少得多，受到各种酸负荷的影响，而且酸化的速度很可能比公海更快。然而，在酸化研究中，这些地区在很大程度上被忽视了。酸化对钙化生物的影响是相似的，无论是酸的来源--大气交换、净异养，还是酸性河水的排放。同样，这些酸通量中的每一个都受到人为活动(例如使用化石燃料、砍伐森林、农业)的干扰。拟议的研究将进一步了解各种酸负荷对沿海水域钙化生物的综合和累积影响。学习的更广泛影响：缅因州圣约瑟夫学院是一所本科院校，有许多潜在的机会向学生介绍科学研究和发现的兴奋。这个项目将对圣约瑟夫学院70%的女性学生具有特殊的意义，她们中的许多人将第一次体验研究科学。学生沉浸在研究中的模式将效仿澳大的其他赞助研究，开设一个新的海洋科学专业，超过35名澳大本科生参加和/或在国内/国际会议上展示研究成果(12人作为合著者)，4名学生共同撰写最近发表的论文。