气候变化领域集成服务门户(CCPortal): Controls on boron isotopes in a cold-water coral and the cost of resilience to ocean acidification

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DOI	10.1016/j.epsl.2020.116662
	Controls on boron isotopes in a cold-water coral and the cost of resilience to ocean acidification
	Gagnon A.C.; Gothmann A.M.; Branson O.; Rae J.W.B.; Stewart J.A.
发表日期	2021
ISSN	0012821X
卷号	554
英文摘要	Coral skeletal growth is sensitive to environmental change and may be adversely impacted by an acidifying ocean. However, physiological processes can also buffer biomineralization from external conditions, providing apparent resilience to acidification in some species. These same physiological processes affect skeletal composition and can impact paleoenvironmental proxies. Understanding the mechanisms of coral calcification is thus crucial for predicting the vulnerability of different corals to ocean acidification and for accurately interpreting coral-based climate records. Here, using boron isotope (δ11B) measurements on cultured cold-water corals, we explain fundamental features of coral calcification and its sensitivity to environmental change. Boron isotopes are one of the most widely used proxies for past seawater pH, and we observe the expected sensitivity between δ11B and pH. Surprisingly, we also discover that coral δ11B is independently sensitive to seawater dissolved inorganic carbon (DIC). We can explain this new DIC effect if we introduce boric acid diffusion across cell membranes as a new flux within a geochemical model of biomineralization. This model independently predicts the sensitivity of the δ11B-pH proxy, without being trained to these data, even though calcifying fluid pH (pHCF) is constant. Boric acid diffusion can resolve why δ11B is a useful proxy across a range of calcifiers, including foraminifera, even when calcifying fluid pH differs from seawater. Our modeling shows that δ11B cannot be interpreted unequivocally as a direct tracer of pHCF. Constant pHCF implies similar calcification rates as seawater pH decreases, which can explain the resilience of some corals to ocean acidification. However, we show that this resilience has a hidden energetic cost such that calcification becomes less efficient in an acidifying ocean. © 2020 Elsevier B.V.
关键词	B/Ca biomineralization boron isotopes coral ocean acidification pH proxy
英文关键词	Biomineralization; Bone; Boric acid; Boride coatings; Boron; Cytology; Diffusion in liquids; Isotopes; Oceanography; Physiology; Seawater; Dissolved inorganic carbon; Environmental change; External conditions; Fundamental features; Geochemical modeling; Ocean acidifications; Physiological process; Skeletal compositions; Acidification; biomineralization; boron isotope; calcium; cold water; coral; ecosystem resilience; ocean acidification; pH; proxy climate record; Anthozoa; Foraminifera
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203093
作者单位	School of Oceanography, University of Washington, Seattle, WA, United States; Joint Institute for the Study of the Atmosphere and Ocean, University of Washington, Seattle, WA, United States; Departments of Physics and Environmental Studies, St. Olaf College, Northfield, MN, United States; Department of Earth Sciences, University of Cambridge, Cambridge, United Kingdom; School of Earth and Environmental Science, University of St. Andrews, St. Andrews, United Kingdom; School of Earth Sciences, University of Bristol, Bristol, United Kingdom
推荐引用方式 GB/T 7714	Gagnon A.C.,Gothmann A.M.,Branson O.,et al. Controls on boron isotopes in a cold-water coral and the cost of resilience to ocean acidification[J],2021,554.
APA	Gagnon A.C.,Gothmann A.M.,Branson O.,Rae J.W.B.,&Stewart J.A..(2021).Controls on boron isotopes in a cold-water coral and the cost of resilience to ocean acidification.Earth and Planetary Science Letters,554.
MLA	Gagnon A.C.,et al."Controls on boron isotopes in a cold-water coral and the cost of resilience to ocean acidification".Earth and Planetary Science Letters 554(2021).