Collaborative Research: Impact of Climate Warming and Ocean Carbonation on Eelgrass (Zostera marina L.)

智力价值：过去几十年来，越来越多的证据表明，人类活动对整个地球的基本生物地球化学过程产生了深远的影响，特别是在支持各种高生产力生态系统的沿海环境中，包括珊瑚礁、海草草甸和河口。海草的生态意义在很大程度上是因为它们对水下水生生物表现出非凡的适应程度。然而，尽管进行了多次成功的适应，但海草对光照的要求很高，这使得它们很容易受到人为干扰。这种矛盾的脆弱性很大程度上是因为它们高度依赖溶解的水二氧化碳进行光合作用。人们很早就认识到，大气中二氧化碳浓度上升可能对全球气候产生显著的变暖影响，但“其他二氧化碳问题”，也称为海洋酸化，其潜在影响直到最近才开始得到重视。与气候变化的其他影响一样，世界海洋中溶解的水二氧化碳[CO2(AQ)]浓度的增加将在生物之间引起积极和消极的反应，最终加剧生态输家和赢家。该项目将结合操作实验、生理/生化研究和数学模型，探索沿海海洋变暖背景下eelgras对增加的二氧化碳(AQ)的反应。研究人员假设，增加二氧化碳(AQ)将通过改善光合作用相对于呼吸作用的Q10响应，从而提高植物的高温耐受性，从而导致更高的生长速度，提高营养枝在高温下的存活率，甚至开花产量和种子产量。该项目将调查对这些至关重要的海洋被子植物的光需求和碳平衡动态具有负面(海洋变暖)和正面(海洋碳化)影响的环境参数之间的关键关系。通过专注于生长在大西洋海岸鳗草分布的南部极限附近的切萨皮克种群，研究人员将获得预测性的洞察，了解气候变化如何改变这种至关重要的物种在其他沿海环境中的地理分布，这些环境可能受到较小的温度压力，但海洋碳酸盐水平相似。广泛的影响：这项工作将为合作者维多利亚·希尔博士提供植物生理学和生物化学方面的培训，并将支持至少两名研究生在为期4年的研究过程中的论文研究。与弗吉尼亚水族馆和海洋科学中心的合作将促进该项目的教育解释和节目的开发，该项目将专门针对每年参观水族馆的65万至70万人。

Intellectual Merit: The past few decades have accumulated mounting evidence of profound anthropogenic effects on fundamental biogeochemical processes across the planet, especially in coastal environments that support a diverse array of highly productive ecosystems including coral reefs, seagrass meadows, and estuaries. The ecological significance of seagrasses is largely due to the remarkable degree of adaptation they exhibit to a submerged aquatic existence. Despite numerous successful adaptations, however, seagrasses have high light requirements that make them vulnerable to anthropogenic disturbances. The paradoxical vulnerability results largely from their high reliance on dissolved aqueous CO2 for photosynthesis. The potential for rising atmospheric CO2 concentrations to have significant warming impacts on the global climate has long been recognized, but the potential impacts of the "other CO2 problem", also known as ocean acidification, have only recently begun to be appreciated. As with other impacts of climate change, the increased concentrations of dissolved aqueous CO2 [CO2 (aq)] in the oceans of the world will elicit both negative and positive responses among organisms, ultimately potentiating ecological losers and winners. This project will explore the response of eelgrass to increased CO2 (aq) within the context of a warming coastal ocean using a combination of manipulative experiments, physiological/biochemical investigations and mathematical modeling. The investigators hypothesize that rising CO2(aq) will increase the high temperature tolerance of plants by improving the Q10 response of photosynthesis relative to respiration, thereby leading to higher growth rates, improved survival of vegetative shoots at high temperature, and even flowering output and seed production. This project will investigate the key relationships between environmental parameters that have both negative (ocean warming) and positive (ocean carbonation) impacts on the light requirements and dynamics of carbon balance in these critically important marine angiosperms. By focusing on Chesapeake populations growing near the southern limit of eelgrass distribution on the Atlantic coast, the investigators will gain predictive insight into how climate change may alter the geographic distribution of this critically important species in other coastal environments that may be subjected to less temperature stress but similar levels of ocean carbonation.Broader Impacts: This work will provide training in plant physiology and biochemistry to the co-PI, Dr. Victoria Hill and will support the dissertation research of at least two graduate students over the course of the 4-year study. Collaboration with the Virginia Aquarium and Marine Science Center will facilitate the development of educational interpretation and programming from this project that will be specifically targeted to the 650,000 to 700,000 people that visit the Aquarium each year.