CAREER: Implications of phytoplankton trait adaptation for biogeochemical cycling

光合作用微生物(浮游植物)对维持地球宜居至关重要。这些微小的生物贡献了全球光合作用的大约一半，并形成了海洋食物网的基础--从而支持了全球渔业和其他海洋生态系统服务。了解这些基本微生物将如何随着海洋的变化而演变，对于预测未来海洋生态系统动态、全球碳循环和气候的变化至关重要。然而，我们仍然缺乏关于浮游植物如何适应未来环境变化的基础知识。此外，全球气候模型中还没有明确包含浮游植物进化的描述。因此，我们对未来碳循环和气候反馈的预测不包括这一将改变海洋生态系统动态的重要机制(进化)。该项目正在开发和测试与浮游植物适应相关的新假设，使用一个将进化理论与生态和物理海洋模型相结合的新框架。该项目调查浮游植物群落动态如何因适应不断变化的海洋而改变，以及这些变化对海洋碳循环的影响。在这个大数据时代，我们必须为学生提供更深入、更严谨的数据分析基础和计算工具体验。该项目正在生成一套计算模块，旨在增加向本科生和K-12级环境研究专业学生提供的定量课程。该课程正在利用在线平台广泛分发，特别侧重于为少数群体服务机构提供机会和培训。该项目的一个关键目标是增加代表不足群体的量化课程，最终目标是增加STEM领域的代表性。该项目通过将特征适应的进化模型与浮游植物动力学的机械性、基于特征的配额模型相结合，为动态环境中的浮游植物特征适应提供新的见解。通过用已发表的实验进化研究的生理学数据明确验证该模型，然后将该模型应用于来自全球循环模型的真实环境波动(温度、光照和营养限制)，这项研究正在扩大浮游植物适应对全球规模的影响。具体地说，该项目正在产生关于多应激源选择压力下适应可能导致的特征变化类型的新假设，限制海洋浮游植物适应的相关时间尺度，并对浮游植物适应对碳循环和生态系统动力学的影响产生新的理解。该项目正在创建一个新的框架，用于理解浮游植物特征适应多重压力的复杂多维问题，以及对未来碳循环可能发生的变化的新理解。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Photosynthetic microbes (phytoplankton) are vitally important for maintaining a habitable planet. These tiny organisms contribute approximately half of global photosynthesis, and form the base of the marine food web -- thereby supporting global fisheries and other marine ecosystem services. Understanding how these essential microbes will evolve as the oceans change is essential for predicting future shifts in marine ecosystem dynamics, global carbon cycling and climate. However, we still lack fundamental knowledge about how phytoplankton may adapt to future environmental changes. In addition, the representation of phytoplankton evolution has not yet been explicitly included in global climate models. As a result, our predictions of future carbon cycling and climate-feedbacks do not include this important mechanism (evolution) that will alter marine ecosystem dynamics. This project is developing and testing new hypotheses related to phytoplankton adaptation using a new framework that combines evolutionary theory with ecological and physical ocean models. This project investigates how phytoplankton community dynamics will be altered by adaptation in a changing ocean and the implications of these changes on ocean carbon cycling. In this age of big data, it is imperative that we provide our students with a deeper, more rigorous foundation in data analysis and experience with computational tools. This project is generating a set of computational modules aimed at increasing the quantitative curriculum provided to environmental studies students at both the undergraduate and K-12 level. This curriculum is being broadly distributed using online platforms with particular focus on providing access and training to Minority Serving Institutions. A key aim of this project is to increase quantitative curriculum for under-represented groups with the ultimate goal of increasing representation in STEM fields.This project is providing new insights into phytoplankton trait adaptation in a dynamic environment by combining an evolutionary model of trait adaptation with a mechanistic, trait-based quota model for phytoplankton dynamics. By explicitly validating the model with physiology data from published experimental evolution studies and then applying the model to realistic environmental fluctuations (temperature, light and nutrient limitation) from a global circulation model, this study is scaling-up the impact of phytoplankton adaptation to the global scale. Specifically, this project is generating new hypotheses about the types of trait changes that might result from adaptation under multi-stressor selective pressure, constraining the relevant timescales for marine phytoplankton adaptation, and creating new understanding of the implications of phytoplankton adaptation for carbon cycling and ecosystem dynamics. The project is creating a novel framework for understanding the complex multi-dimensional problem of phytoplankton trait adaptation to multi-stressors and new understanding of how carbon cycling might change in the future.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.