Postdoctoral Fellowship: OCE-PRF: Quantifying the effects of ocean alkalinity enhancement on costal ecosystems and atmospheric carbon dioxide

过去两年来，科技行业对二氧化碳去除技术的投资迅速增加，加速了已经在自然生态系统中发挥作用的海洋碱度增强（OAE）公司的创建。然而，我们对大气中二氧化碳（CO2）的橄榄石溶解的理解仍处于起步阶段。此外，没有研究量化的影响，橄榄石引起的OAE对底栖生物礁群落的OAE测试网站的人口。该提案的目标是描述OAE对珊瑚礁底栖生物和水中微生物群落功能的影响，以设计一个衡量、报告和核查框架。该提案将通过恒化器实验、天然橄榄石海滩实地调查和生物地球化学建模，评估对环境和大气CO2的潜在影响。受控恒化器实验将能够直接测量橄榄石溶解产物，包括次生矿物沉淀及其对珊瑚礁群落动态的影响。拟议的研究将有助于了解新的基础知识：1）量化橄榄石在生态相关海水系统中的溶解速率; 2）响应橄榄石OAE的大气CO2通量和速率; 4）对珊瑚礁群落功能的影响。尽管多项研究已经确定了合理的脱靶效应，例如产生有毒镍以及改变与颗粒相关的微生物群落组成。在更多的OAE公司成立并开始影响这些重要的珊瑚礁生态系统之前，必须量化这些不确定性和生态系统影响。该提案旨在：1）描述OAE对主要的礁底栖初级生产者、其相关微生物群落和溶解有机物循环的影响; 2）量化礁生态系统中橄榄石的溶解速率和由此产生的大气CO2的下降; 3）开发一个地球化学-水动力耦合模型，以预测橄榄石OAE在开阔海洋系统中的功效，并量化区域尺度上大气CO2的去除; 4）为OAE的衡量、核实和报告制定新的方法和标准。这项工作有可能在OAE领域取得变革性进展，并引导这一新行业的规模扩大到最适合捕获大气中最多二氧化碳的系统，而不会影响其他重要的生态系统。该项目解决了美国国家科学院、工程院和医学院面临的挑战：开发OAE的经验框架，评估方法与环境影响之间的关系，制定稳健的测量、报告和验证策略。由于有效实施AOE迫切需要数据和准确的模型，一旦有任何数据可用，所有数据，实地研究和模型都将通过github存储库随时可用，该项目由GEO/OCE博士后奖学金计划和刺激竞争性研究的既定计划（EPSCoR）共同资助。该奖项反映了NSF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。

Rapidly increasing investment over the past two years into carbon dioxide removal technologies from the tech industry has accelerated the creation of ocean alkalinity enhancement (OAE) companies which are already acting in natural ecosystems. However, our understanding of olivine dissolution on atmospheric carbon dioxide (CO2) is still in its infancy. Moreover, no studies have quantified the impact of olivine induced OAE on the benthic reef communities which populate the OAE test sites. The goal of this proposal is to characterize the effects of OAE on the functioning of the coral reef benthos and water microbial community to design a framework for measurement, reporting and verification. This proposal will evaluate the potential impacts on both the environment and atmospheric CO2, through chemostat experiments, field surveys of natural olivine beaches and biogeochemical modeling. Controlled chemostat experiments will enable direct measurement of the olivine dissolution products including secondary mineral precipitation and their effect on reef community dynamics. The proposed research will contribute novel, fundamental knowledge to understand: 1) quantification of the dissolution rate of olivine in an ecologically relevant seawater system; 2) flux and rate of atmospheric CO2 in response to olivine OAE; 4) impact on coral reef community function. Although multiple studies have identified plausible off-target effects such as the creation of toxic nickel as well as shifting the particle-associated microbial community composition. Before more OAE companies are created and begin impacting these vital reef ecosystems, these uncertainties and ecosystem impacts must be quantified. This proposal aims to: 1) characterize the impact of OAE on dominant reef benthic primary producers, their associated microbial communities, and dissolved organic matter cycling; 2) quantify olivine dissolution rate in reef ecosystems and the resultant drawdown of atmospheric CO2; 3) develop a biogeochemical-hydrodynamic coupled model to predict the efficacy of olivine OAE in open-ocean systems and quantify atmospheric CO2 removal on a regional scale; 4) develop new methodologies and criteria for measurement, verification and reporting for OAE. This work has the potential to make transformative advances in OAE and guide the scaling of this new industry to systems which are best equipped to capture the most atmospheric CO2 without impacting other vital ecosystems. This project addresses challenges addressed in the National Academies of Sciences, Engineering, and Medicine: Development of an empirical framework for OAE, Assessment of the relationship between approach and environmental impact development of robust measurement, reporting, and verification strategies. Due to the immediate need of data and accurate models for effective implementation of AOE, all data, field studies, and models will be readily available through a github repository as soon as any data becomes available, prior to publication.This project is jointly funded by GEO/OCE Postdoctoral Fellowships Program and the Established Program to Stimulate Competitive Research (EPSCoR).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.