Collaborative Research: ORCC: Carryover effects of multiple climate change stressors in oysters: mechanisms and consequences across stages of ontogeny

气候变化使物种暴露在多种压力之下，影响它们的生长、繁殖和提供造福人类的生态系统服务的能力。然而，在生物体的一生中反复暴露于相同的应激源可能会使某些物种适应并避免这些负面影响，特别是如果最初的暴露发生在个体年轻的时候。这项研究使用牡蛎来实验测试早期生命暴露在海洋变暖和低溶解氧下如何影响牡蛎在以后的生活中对这些同样的应激源的反应。东方牡蛎是一种重要的经济物种，它为人类提供生态系统服务，如减少沿海系统的氮负荷，保护海岸线免受风暴的影响。但牡蛎的生存和生长受到陆地高营养径流和大气二氧化碳和温度上升导致的溶解氧下降的负面影响。这些发现将提高我们对重复压力暴露如何影响物种对气候变化的反应的理解，以及重复压力暴露是否可以作为一种工具来改善水产养殖和资源管理中的食品和工作安全。这一潜在战略将在一系列研讨会上与马里兰州各地的水产养殖利益攸关方分享。它将吸引研究生和本科生从事科学研究。它还将通过开发和分发Science-to-Go模块，向小学到高中的学生介绍气候变化的概念和海洋生态系统对人类福祉的重要性，这些模块提供与该项目相关的主题的家庭科学活动工具包。表型可塑性是生物体对气候变化反应的重要组成部分，但通常只研究与个人当前环境有关的问题。然而，生物体表型经常受到过去环境经验的影响，例如那些发生在生命早期的环境经验，但人们对这些“世代内遗传效应”或驱动它们的机制如何在有机体个体发育中持续和变化知之甚少。这项拟议的研究将探索生命早期暴露于两种相互作用的气候变化应激源--缺氧和变暖--如何影响东方牡蛎(Crassostrea Virgiica)的健康，以及这些影响在个体发育过程中的多年和多个时间点产生的潜在机制和生态后果。这项研究包括实验室和现场(在水产养殖场)的一系列操纵实验，并分析了牡蛎在每个个体发育阶段的适合度、微生物群、甲基组和氮含量。需要了解随时间变化的可塑性以及过去环境对生物体特征的持久影响，这对于准确预测生物体对气候变化的反应至关重要。由于气候变化增加了生物体在其一生中反复暴露于相同应激源的可能性，代内延续效应在适应反应中可能发挥着越来越重要的作用。结转效应可能是一种使生物体快速适应未来环境的手段，可以与选择性育种结合使用，以创造更具弹性的生物体。因此，这项研究将产生关于应对气候变化对水产养殖和沿海系统影响的潜在战略的数据。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。

Climate change is exposing species to multiple stressors that affect their ability to grow, reproduce, and provide ecosystem services that benefit humans. However, repeated exposure to the same stressors over an organism’s lifetime may allow some species to acclimate and avoid these negative effects, especially if the initial exposure occurs when an individual is young. This study uses oysters to experimentally test how early life exposure to ocean warming and low dissolved oxygen affects oysters’ responses to these same stressors later in life. The eastern oyster is an economically important species that provides ecosystem services to humans such as reducing nitrogen loading to coastal systems and protecting shorelines from storms. But oyster survival and growth are negatively affected by declining dissolved oxygen caused by high nutrient runoff from land and rising atmospheric carbon dioxide and temperature. The findings will improve our understanding of how repeated stress exposure affects species’ responses to climate change, and whether repeated exposure is a tool that can be harnessed to improve food and job security in aquaculture and resource management. This potential strategy will be shared with aquaculture stakeholders throughout Maryland in a series of workshops. It will engage graduate students and undergraduates in scientific research. It will also introduce elementary through high school students to the concepts of climate change and the importance of marine ecosystems to human well-being through the development and distribution of Science-to-Go modules that provide at-home science activity kits on topics related to the project.Phenotypic plasticity is an important component of organismal responses to climate change, but is typically examined only in relation to an individual’s current environment. However, organism phenotypes are frequently influenced by past environmental experiences such as those that occur early in life, but little is known about how these “within-generation carryover effects,” or the mechanisms that drive them, persist and change across organism ontogeny. The proposed research will explore how early life exposure to two interacting climate change stressors – hypoxia and warming – impacts eastern oyster (Crassostrea virginica) fitness as well as the potential mechanisms and ecological consequences of these carryover effects across multiple years and at multiple points during ontogeny. This study involves a series of manipulative experiments in the lab and field (on an aquaculture farm) and analyzes oyster fitness, microbiomes, methylomes, and nitrogen content at each ontogenetic stage. The need to understand plasticity through time and the lasting influence of past environments on organism traits is critical to accurately predict organismal responses to climate change. Because climate change is increasing the likelihood that organisms will be exposed to the same stressors repeatedly over their lifetimes, within-generation carryover effects may play an increasingly important role in adaptive responses. Carryover effects may be a means of quickly acclimating organisms to future environments that can be used in conjunction with selective breeding to create more resilient organisms. This research will thus generate data on a potential strategy for addressing effects of climate change on aquaculture and coastal systems.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.