Ocean Acidification, Hypoxia and Warming: Experimental Investigations into Compounded Effects of Global Change on Benthic Foraminifera

过去100年来，平均海表面温度(SST)有所上升，大气中二氧化碳分压(PCO2)的上升正在降低海洋的pH值，低氧底层水域的范围和强度正在增加，至少在某些区域是这样。这些正在进行的变化--变暖、酸化和缺氧--的生物学影响都得到了独立的研究，但很少有研究探索这些应激源之间可能的相互作用。这项研究由伍兹霍尔海洋研究所的一位科学家领导，研究了海洋酸化、缺氧和变暖对从新英格兰近海大陆架收集的底栖有孔虫组合的综合影响。有孔虫是这项工作的理想生物，因为它们(1)相对较小，可以在具有统计意义的种群上进行实验；(2)既有钙质的代表，也有非钙质的代表；(3)寿命相对较短，因此实验包括它们生命周期的主要部分；(4)包括好氧和厌氧生物；以及(5)提供化石记录，以便进行跨时间的比较。实验室培养实验将用来确定底栖有孔虫的生存和生长对共同变化的pH和氧气参数的反应，并探索温度升高对这些反应的影响。研究人员将研究较高的二氧化碳、较低的[O2]和较高的温度(T)对钙质和非钙质底栖有孔虫的相对影响。此外，他们将检查现场的工业化前底栖有孔虫组合，并将该组合与在工业化前(低于当前水平)和二氧化碳水平升高的实验中产生的组合进行比较。全球变暖、海洋酸化、海洋缺氧(“死区”)及其对海洋动植物的影响具有相当大的社会意义。该项目的资金支持一名博士后研究人员，两名本科生的暑期研究项目，并为大约十名额外的本科生提供第一次海上航行经验。此外，每年将至少招募一名当地高中生来开展一个附属的气候变化科学博览会项目。

The average sea surface temperature (SST) has increased over the last 100 years, rising atmospheric partial pressure of carbon dioxide (pCO2) is lowering the pH of the oceans, and the extent and intensity of low-oxygen bottom waters is growing, at least in certain regions. The biological impacts of these ongoing changes -- warming, acidification, and hypoxia -- have each been studied independently, but few studies have explored the possible interactions among these stressors. This research, led by a scientist from the Woods Hole Oceanographic Institution, studies the compounded effects of ocean acidification, hypoxia, and warming on an assemblage of benthic foraminifera collected from the continental shelf off New England. Foraminifera are an ideal organism for this work because they (1) are relatively small, allowing experimentation on statistically significant populations; (2) have both calcareous and non-calcareous representatives; (3) are relatively short-lived so experiments include a major portion of their life cycle; (4) include aerobes and anaerobes; and (5) provide a fossil record allowing comparisons across time. Laboratory culturing experiments will be used to determine the response of benthic foraminifera, in terms of survival and growth, to co-varying parameters of pH and oxygen, and to explore the influence of increased temperature on these responses. The researchers will examine the relative effects of higher pCO2, lower [O2], and higher temperature (T) on both calcareous and non-calcareous benthic foraminifera. In addition, they will examine the pre-Industrial benthic foraminiferal assemblage at the field site, and will compare that assemblage to those produced in the experiments under pre-Industrial (lower than current day) and elevated pCO2 levels. Global warming, ocean acidification, ocean hypoxia ("dead zones"), and their effect on marine flora and fauna, are of considerable societal interest. Funding of this project supports a Post-Doctoral Investigator, summer research projects of two undergraduate students, and provides a first seagoing experience for approximately ten additional undergraduate students. Also, at least one local high school student will be recruited each year to conduct an affiliated climate-change science fair project.