Ocean Acidification: Seasonal and Ontogenetic Effects of Ocean Acidication on Pteropods in the Gulf of Maine

海洋酸化：海洋酸化对缅因湾翼足类动物的季节性和个体发育影响

• 批准号: 1316040
• 负责人: Gareth Lawson
• 金额: $ 49.27万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2017-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1316040&HistoricalAwards=false
• 关键词: Ocean; Acidification; Seasonal; Ontogenetic; Effects

Dissolution of excess anthropogenic CO2 into the ocean is causing the marine environment to decrease in pH. This "ocean acidification" is predicted to threaten a broad variety of marine organisms, particularly calcifying animals such as the thecosome (i.e., shelled) pteropods. These pelagic gastropods form an aragonite shell, are prey for a number of commercially important fish, and are significant contributors to carbon biogeochemistry. Their ecosystem importance, abundance, and sensitivity to dissolution position them as an important group for investigating the impacts of acidification. Our understanding of the effect of high CO2 on pteropods and the pelagic ecosystem, however, is limited primarily to short-term studies of adult calcification and respiration response in the polar ecosystems. There have been no seasonal studies of sensitivity and our understanding of the effect of CO2 on pteropod early life stages is limited. Limacina retroversa is a particularly abundant thecosome pteropod in the North Atlantic, where it is prey for a number of fisheries species and other top predators. This species is also the most common pteropod in the Gulf of Maine (GoM) where it is present year round. L. retroversa thus offers the prospect of a useful model pteropod species, given both its ecological importance and its abundance in readily accessible waters. The investigators will conduct a series of short cruises to sample L. retroversa on a seasonal basis from local waters of the GoM near Cape Cod. The carbonate chemistry of the GoM fluctuates seasonally, proving them with the opportunity to assess the response of wild caught pteropods to natural changes in CO2. By characterizing the carbonate chemistry of the water column and measuring the metabolic rate, shell quality, and gene expression of pteropods throughout the year, the researchers will achieve a time series of pteropod sensitivity to CO2. Subsequently, using experimental manipulations the investigators will explore the effect of seasonal acclimation on pteropod response to short- and medium-term exposure to enhanced CO2. Pteropods frequently lay eggs in captivity, and at WHOI there is institutional expertise in maintaining these individuals in the laboratory. Building on these strengths, the researchers will also study the effect of CO2 on embryonic and larval development in L. retroversa. These earliest life-stages of marine calcifiers are thought to be especially sensitive since initial shell precipitation and the highly energetic processes of growth and development are impeded by CO2 exposure. They will also document mortality, shell production, abnormality, and developmental rate of clutches of pteropod embryos exposed to increased CO2.Intellectual Merit: Thecosome pteropods are an abundant group of calcifying zooplankters that have been chronically understudied, particularly in temperate regions. Due to its accessibility and ecological importance, L. retroversa can be developed as a valuable model, interesting both as the dominant pteropod in the commercially-important GoM region and also an abundant pteropod in the temperate waters of the North Atlantic. The goal of this research is to augment our knowledge of the distribution of L. retroversa, to attain an understanding of their seasonal sensitivity to natural variability in CO2, and to see how this exposure impacts responses to both short- and medium-term CO2 exposure. Using powerful transcriptomic technologies, the research will transform our understanding of this group by investigating the molecular mechanisms of response in L. retroversa to both seasonality and varying durations and intensities of acidification, contextualized by ecosystem- and organism-level metrics. Furthermore the study will examine the effect of CO2 on the eggs of pteropods for the first time, providing insight into their sensitivity to an acidifying environment.Broader Impacts: Ocean acidification is increasingly appreciated as an urgent societal concern. Thecosomes are important in biogeochemical cycles and as key prey for a variety of commercial fish and as such, the improved understanding we seek of pteropod ecology will have important implications for our understanding of the effects of ocean acidification on marine resources. The project will integrate research with education in a number of ways, including the training of undergraduate students as well as serving as a seminal experience in the career development of postdoc (and co-PI) Dr. Maas. Furthermore, taking advantage of the aesthetic appeal of these charismatic microfauna, the researchers will pair with journalists, artists, and photographers to continue to develop images and exhibitions aimed at increasing public awareness of the impacts of ocean acidification.

过量的人为二氧化碳溶解到海洋中导致海洋环境的 pH 值下降。据预测，这种“海洋酸化”将威胁多种海洋生物，特别是钙化动物，例如壳体（即带壳）翼足类动物。这些远洋腹足动物形成文石壳，是许多具有重要商业价值的鱼类的猎物，并且是碳生物地球化学的重要贡献者。它们的生态系统重要性、丰富性和对溶解的敏感性使它们成为研究酸化影响的重要群体。然而，我们对高二氧化碳对翼足类动物和远洋生态系统影响的了解主要仅限于对极地生态系统中成体钙化和呼吸反应的短期研究。目前还没有针对敏感性的季节性研究，而且我们对二氧化碳对翼足类早期生命阶段影响的了解也很有限。 Limacina Retroversa 是北大西洋中一种特别丰富的壳体翼足类动物，是许多渔业物种和其他顶级掠食者的猎物。该物种也是缅因湾 (GoM) 最常见的翼足类动物，常年出现在该地区。因此，考虑到其生态重要性和在容易到达的水域中的丰富性，逆转录L.retroversa 提供了一种有用的翼足类动物模型的前景。研究人员将进行一系列短途巡航，按季节从科德角附近的墨西哥湾当地水域采集逆转录乳杆菌样本。墨西哥湾的碳酸盐化学成分随季节波动，这证明他们有机会评估野生捕获的翼足类动物对二氧化碳自然变化的反应。通过表征水体的碳酸盐化学并测量翼足类动物全年的代谢率、壳质量和基因表达，研究人员将获得翼足类动物对二氧化碳敏感性的时间序列。随后，研究人员将利用实验操作探讨季节性适应对翼足类动物对短期和中期暴露于增强二氧化碳的反应的影响。翼足类动物经常在圈养下产卵，WHOI 拥有在实验室中维持这些个体的机构专业知识。基于这些优势，研究人员还将研究二氧化碳对逆转录乳杆菌胚胎和幼虫发育的影响。人们认为海洋钙化物的这些最早的生命阶段特别敏感，因为最初的壳沉淀以及高能量的生长和发育过程都会受到二氧化碳暴露的阻碍。他们还将记录暴露在增加的二氧化碳中的翼足类胚胎的死亡率、产壳情况、异常情况和发育率。 智力优点：翼足类壳体是一群丰富的钙化浮游动物，长期以来一直未被充分研究，特别是在温带地区。由于其可及性和生态重要性，L.retroversa 可以开发为一种有价值的模型，既是具有商业重要性的 GoM 地区的优势翼足类动物，也是北大西洋温带水域中丰富的翼足类动物。这项研究的目的是增强我们对逆转录乳杆菌分布的了解，了解它们对二氧化碳自然变化的季节性敏感性，并了解这种暴露如何影响对短期和中期二氧化碳暴露的反应。该研究将使用强大的转录组技术，通过研究逆转录乳杆菌对季节性和不同持续时间和酸化强度的反应分子机制，并以生态系统和生物体水平指标为背景，改变我们对这一群体的理解。此外，该研究将首次研究二氧化碳对翼足类动物卵的影响，深入了解它们对酸化环境的敏感性。更广泛的影响：海洋酸化越来越被视为一个紧迫的社会问题。卵泡体在生物地球化学循环中很重要，并且是各种商业鱼类的主要猎物，因此，我们对翼足类生态学的进一步了解将对我们了解海洋酸化对海洋资源的影响产生重要影响。该项目将以多种方式将研究与教育结合起来，包括培训本科生以及为博士后（兼联合首席研究员）马斯博士的职业发展提供开创性的经验。此外，利用这些魅力十足的微型动物的审美吸引力，研究人员将与记者、艺术家和摄影师合作，继续开发图像和展览，旨在提高公众对海洋酸化影响的认识。