Collaborative research: Understanding the effects of acidification and hypoxia within and across generations in a coastal marine fish

沿海海洋生态系统为人类提供了许多重要的服务和资源，与此同时，沿海水域也受到海洋酸化加剧和溶解氧减少等环境压力的影响。这些压力源对沿海海洋生物的影响仍然知之甚少，因为迄今为止大多数研究都只考察了物种对一个因素的敏感性，而不是对一个以上因素的敏感性。该项目将确定一种模式鱼类——大西洋银鱼——将如何对观测到的和预测的溶解二氧化碳（CO2）和氧气（O2）水平做出反应。短期实验将测量胚胎和幼虫的存活、生长和新陈代谢，并确定经历压力条件的父母是否能产生更健壮的后代。长期实验将通过量化高二氧化碳环境对男女比例、终生生长和生殖投资的影响，研究海洋酸化在整个生命周期中的后果。这些研究将提供一个更全面的观点，多种压力因素如何影响大西洋银鱼和潜在的其他重要饲料鱼类物种的种群。这个合作项目将支持和培训康涅狄格大学和纽约石溪大学的三名研究生，这两所大学吸引的都是少数族裔学生。它还将为本科生提供各种参与研究和公众了解研究的机会，包括夏季研究项目，纳入“科学与工程中的女性”计划，以及监测浮标的环境数据的互动展示。这两位职业生涯早期的研究人员致力于通过公开演讲和演讲来提高人们对海洋的了解和对nsf资助的研究的认识。该项目响应了对物种对人为环境变化敏感性的多压力源评估的公认需求。它将环境监测与先进的实验方法相结合，以表征大西洋银鱼（Menidia Menidia）酸化和缺氧的早期和整个生命的后果，这是一种有价值的模式物种，也是美国东海岸大部分地区重要的饲料鱼。实验将采用一个新建的计算机控制的养鱼系统，允许独立和联合操纵海水二氧化碳分压和溶解氧（DO）含量，并应用静态和波动的二氧化碳分压和溶解氧水平，这些水平被选择来代表生产性沿海生境的当代和潜在的未来情景。首先，采用3 CO2 × 3 DO水平的全因子设计，通过饲养从受精到孵化后20天（dph）收集的野生成虫后代，量化与健康相关的早期生活史（ELH）性状，包括孵化前和孵化后存活率、孵化时间、孵化后生长。其次，量化潮汐和日间不同幅度的CO2 × DO波动对银鱼ELH性状的影响。为了解决关于该物种二氧化碳敏感性的知识空白，实验室操作的成虫产卵环境和相互后代暴露实验将阐明跨代可塑性作为应对环境变化的潜在短期机制的作用。为了更好地了解鱼类早期CO2敏感性的机制，将对温度× CO2对孵化前后代谢的影响进行稳健量化。最终目的是在不同的CO2水平下对银鱼从受精到成熟进行饲养，并评估CO2对性别比例、终生生长和繁殖力的潜在影响。

Coastal marine ecosystems provide a number of important services and resources for humans, and at the same time, coastal waters are subject to environmental stressors such as increases in ocean acidification and reductions in dissolved oxygen. The effects of these stressors on coastal marine organisms remain poorly understood because most research to date has examined the sensitivity of species to one factor, but not to more than one in combination. This project will determine how a model fish species, the Atlantic silverside, will respond to observed and predicted levels of dissolved carbon dioxide (CO2) and oxygen (O2). Shorter-term experiments will measure embryo and larval survival, growth, and metabolism, and determine whether parents experiencing stressful conditions produce more robust offspring. Longer-term experiments will study the consequences of ocean acidification over the entire life span by quantifying the effects of high-CO2 conditions on the ratio of males to females, lifetime growth, and reproductive investment. These studies will provide a more comprehensive view of how multiple stressors may impact populations of Atlantic silversides and potentially other important forage fish species. This collaborative project will support and train three graduate students at the University of Connecticut and the Stony Brook University (NY), two institutions that attract students from minority groups. It will also provide a variety of opportunities for undergraduates to participate in research and the public to learn about the study, through summer research projects, incorporation in the "Women in Science and Engineering" program, and interactive displays of environmental data from monitoring buoys. The two early-career investigators are committed to increasing ocean literacy and awareness of NSF-funded research through public talks and presentations. This project responds to the recognized need for multi-stressor assessments of species sensitivities to anthropogenic environmental change. It will combine environmental monitoring with advanced experimental approaches to characterize early and whole life consequences of acidification and hypoxia in the Atlantic silverside (Menidia menidia), a valued model species and important forage fish along most of the US east coast. Experiments will employ a newly constructed, computer-controlled fish rearing system to allow independent and combined manipulation of seawater pCO2 and dissolved oxygen (DO) content and the application of static and fluctuating pCO2 and DO levels that were chosen to represent contemporary and potential future scenarios in productive coastal habitats. First CO2, DO, and CO2 × DO dependent reaction norms will be quantified for fitness-relevant early life history (ELH) traits including pre- and post-hatch survival, time to hatch, post-hatch growth, by rearing offspring collected from wild adults from fertilization to 20 days post hatch (dph) using a full factorial design of 3 CO2 × 3 DO levels. Second, the effects of tidal and diel CO2 × DO fluctuations of different amplitudes on silverside ELH traits will be quantified. To address knowledge gaps regarding the CO2-sensitivity in this species, laboratory manipulations of adult spawner environments and reciprocal offspring exposure experiments will elucidate the role of transgenerational plasticity as a potential short-term mechanism to cope with changing environments. To better understand the mechanisms of fish early life CO2-sensitivity, the effects of temperature × CO2 on pre- and post-hatch metabolism will be robustly quantified. The final objective is to rear silversides from fertilization to maturity under different CO2 levels and assess potential CO2-effects on sex ratio and whole life growth and fecundity.