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，同时，沿海沃茨受到环境压力因素的影响，如海洋酸化加剧和溶解氧减少。这些压力对沿海海洋生物的影响仍然知之甚少，因为迄今为止的大多数研究都研究了物种对一个因素的敏感性，但没有对一个以上的组合。该项目将确定一种模式鱼类大西洋银汉鱼将如何对观测和预测的溶解二氧化碳（CO2）和氧气（O2）水平作出反应。短期实验将测量胚胎和幼虫的存活、生长和代谢，并确定经历压力条件的父母是否能产生更健壮的后代。长期实验将研究海洋酸化对整个生命周期的影响，方法是量化高二氧化碳条件对男女比例、终生生长和生殖投资的影响。这些研究将提供一个更全面的观点，如何多重压力可能会影响人口的大西洋银鱼和潜在的其他重要饲料鱼类。这一合作项目将支持和培训康涅狄格大学和斯托尼布鲁克大学（纽约）的三名研究生，这两所大学吸引少数群体学生。它还将通过暑期研究项目、纳入“妇女参与科学和工程”方案以及监测浮标环境数据的互动展示，为本科生参与研究和公众了解这项研究提供各种机会。这两位早期职业调查员致力于通过公开讲座和演讲提高海洋素养和对NSF资助研究的认识。该项目响应了公认的对物种对人为环境变化的敏感性进行多压力源评估的需要。它将联合收割机环境监测与先进的实验方法相结合，以表征大西洋银汉鱼（Menidia menidia）的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，也是美国东海岸沿着大部分地区的重要饲料鱼。实验将采用一个新建成的，计算机控制的鱼类饲养系统，允许独立和联合操纵海水pCO2和溶解氧（DO）含量和应用程序的静态和波动的pCO2和DO水平，选择代表当代和潜在的未来情景在生产性沿海栖息地。首先，将使用3个CO2 × 3 DO水平的全析因设计，通过饲养从受精至孵化后20天（dph）从野生成虫中收集的后代，量化适合度相关早期生活史（ELH）性状的CO2、DO和CO2 × DO依赖性反应规范，包括孵化前和孵化后存活率、孵化时间、孵化后生长。第二，将量化不同幅度的潮汐和昼夜CO2 × DO波动对银汉鱼ELH性状的影响。为了解决这个物种的CO2敏感性的知识差距，成年产卵环境和互惠后代暴露实验室操作将阐明跨代可塑性的作用，作为一个潜在的短期机制，以科普不断变化的环境。为了更好地理解鱼类早期生命CO2敏感性的机制，温度× CO2对孵化前后代谢的影响将被稳健地量化。最终的目标是饲养银汉鱼从受精到成熟在不同的CO2水平和评估潜在的CO2对性比和整个生命的生长和繁殖力的影响。

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.