Collaborative Research: Reevaluating calcification response to changes in seawater chemistry by testing the Proton Flux Hypothesis and the Coral Metabolism Model

珊瑚构建碳酸钙骨架来维持珊瑚礁的三维结构，为许多生物提供栖息地，并保护海岸线免受生物侵蚀和风暴破坏。然而，海洋化学的变化威胁着珊瑚建造和维持这些重要生态结构的能力。为了进一步了解气候变化如何影响珊瑚礁，该项目研究了海洋碳酸盐化学变化如何直接影响珊瑚钙化。研究人员正在对在海水水箱中生长的珊瑚进行一系列实验，以研究珊瑚在不断变化的海洋中对海水化学的反应。该项目更广泛的影响包括学生研究机会、科学探究实验室和虚拟学习。本项目支持培养化学、工程、海洋生态等学科的几名早期科研人员、博士生、本科生和高中生。研究人员与德克萨斯州水族馆合作，通过虚拟研究探险系列与公众交流，重点关注珊瑚礁健康。这个系列包括采访、幕后之旅和夏威夷珊瑚礁的虚拟潜水。本项目通过研究珊瑚周围微环境中海水化学的调节，探讨了海水化学与珊瑚生理之间的基本联系。具体来说，本项目1)研究了珊瑚对不同碳酸盐化学的反应，2)表征了不同海洋酸化条件下珊瑚边界层的质子梯度。这项工作的结果分离了碳酸盐离子还是氢离子对钙化速率的影响更大。这项工作利用了一个最先进的实验介环境设施，该设施结合了一个自动化系统，可以同时独立地控制水箱中的总碱度和二氧化碳，以检查珊瑚在不同碳化学情景下的反应。珊瑚周围碳化学的小范围梯度正在使用一种创新的固态无试剂传感器进行表征，该传感器能够同时测量两个关键的碳系统参数。珊瑚生物反应变量在短期孵育和长期中观环境操作期间被量化，以了解跨多个尺度（即个体和群落尺度）和跨边界层的生理影响。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Corals build calcium carbonate skeletons to maintain the three-dimensional structure of a coral reef, which provides habitat for many organisms and protects shorelines from bioerosion and storm damage. However, changes in ocean chemistry threaten the ability of corals to build and sustain these ecological important structures. To further the understanding of how climate change impacts coral reefs, this project investigates how changes in ocean carbonate chemistry directly influence coral calcification. The researchers are conducting a series of experiments on corals grown in seawater tanks to study corals responses to seawater chemistry in a changing ocean. Broader impacts of the project include student research opportunities, science-inquiry labs, and virtual learning. This project supports the training of several early career researchers, Ph.D. students, undergraduates, and high school students in the disciplines of chemistry, engineering, and marine ecology. Researchers partner with the Texas State Aquarium to communicate with the general public through a virtual research expedition series that will focus on coral reef health. This series includes interviews, behind the scene tours, and virtual dives on coral reefs in Hawaii.This project examines the fundamental connections between seawater chemistry and coral physiology by investigating the modulation of seawater chemistry in the microenvironment surrounding corals. Specifically, this project 1) examines the response of corals to differing carbonate chemistry and 2) characterizes the proton gradient across the corals' boundary layers under differing ocean acidification conditions. Results of this work isolate whether carbonate ions or hydrogen ions have a stronger influence on calcification rates. This work utilizes a state-of-the-art experimental mesocosm facility that combines an automated systems to simultaneously and independently control both total alkalinity and carbon dioxide in the tanks to examine coral response under different carbon chemistry scenarios. Small-scale gradients in carbon chemistry surrounding the corals are being characterized using an innovative solid-state, reagentless sensor capable of making simultaneous measurements of two critical carbon system parameters. Coral biological response variables are quantified during short-term incubations and long-term mesocosm manipulations to understand physiological implications across multiple scales (i.e., individual and community scales) and across boundary layers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.