Collaborative: BEE: C-EVO: Linking Carbon cycling to eco-EVOlutionary responses of a foundational plant to global change

人们越来越认识到对环境变化的进化反应如何改变重要的生态系统属性。本项目旨在研究生态优势植物对大气二氧化碳浓度升高和氮富集的进化响应如何影响沿海沼泽生态系统的碳流入和流出。研究人员计划利用一项长期实验来描述植物性状是如何影响光合作用的，沼泽沉积物中有机物的分解，以及沉积物的增加是如何随着二氧化碳和氮的可用性的增加而变化的。然后，他们计划为这些特征建立潜在的遗传基础，这样基因变异的变化就可以用来证实进化已经发生。最后，研究人员计划量化性状变化及其相关的遗传变异对高产沼泽生态系统中长期碳储存或损失的影响。这将使研究人员能够确定沿海沼泽中植物进化和碳循环之间的机制和功能联系，由于预期的海平面上升，这些沼泽面临着不确定的未来。这项研究的发现有可能提高我们对全球碳预算的理解，并通过提高我们对沼泽持久性的理解来促进更有效的沿海恢复。此外，该项目可以加强研究基础设施，创造新的教育和推广机会，包括公民科学家的参与，并促进来自科学界代表性不足群体的学生的本科研究。该项目采用了一套互补的研究，旨在明确地连接进化生物学和生态系统生态学。利用新实验和正在进行的长期全球变化实验的组织档案，研究人员计划利用ddrad产生的snp同时分析原位遗传和基因组变异，表征田间功能性状（如最大光合作用速率、气孔导度和水分利用效率）变异，并量化完整的沼泽碳预算（如量化NPP、气体C损失、凋落物分解率、土壤质量和土壤质量）。地下生物量和碳积累)。这些测量是在十多年二氧化碳和氮浓度升高的背景下进行的。为了进一步建立性状、遗传变异和碳通量之间的联系，研究人员计划对性状变异和生理进行一项补充性的从头开始的定量遗传学研究，目的是将两者与植物个体介导的碳通量联系起来。建立这样的机制联系可以改善沿海沼泽碳循环机制模型的参数化，从而能够更彻底地表征生物进化的生态系统级后果。这个项目的发现可以说明生物进化是否是生态系统功能的重要决定因素，并为全球变化如何直接和间接改变生态系统提供新的见解。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。

There is a growing appreciation for how evolutionary responses to environmental change can alter vital ecosystem attributes. This project aims to study how evolutionary responses of an ecologically dominant plant to elevated atmospheric carbon dioxide concentration and nitrogen enrichment influence the flow of carbon into and out of coastal marsh ecosystems. The researchers plan to leverage a long-term experiment to characterize how plant traits that impact photosynthesis, the decomposition of organic matter in marsh sediments, and sediment accretion shift in response to increased carbon dioxide and nitrogen availability. They then plan to establish the underlying genetic basis for these traits, so that changes in genetic variation can be used to confirm that evolution has taken place. And finally, the researchers plan to quantify the consequences of changes in traits, and their associated genetic variation, for long-term carbon storage in, or loss from, highly productive marsh ecosystems. This would enable the researchers to identify mechanistic and functional links between plant evolution and carbon cycling in coastal marshes, which face an uncertain future due to anticipated sea-level rise. Findings from this research have the potential to improve our understanding of the global carbon budget, and to foster more effective coastal restoration by advancing our understanding of marsh persistence. Furthermore, the project can strengthen research infrastructure, create new educational and outreach opportunities, including the engagement of citizen scientists, and facilitate undergraduate research by students from groups underrepresented in science.This project employs a complementary set of studies explicitly designed to bridge evolutionary biology and ecosystem ecology. Using a combination of new experiments and tissue archives from an ongoing, long-term global change experiment, the researchers plan to simultaneously assay in situ genetic and genomic variation using ddRAD-generated SNPs, to characterize functional trait (e.g. maximum rates of photosynthesis, stomatal conductance, and water use efficiency) variation in the field, and to quantify complete marsh carbon budgets (e.g. quantifying NPP, gaseous C losses, litter decomposition rate, and belowground biomass and C accumulation). These measurements are set in the context of more than a decade of exposure to elevated CO2 and nitrogen enrichment. To go beyond establishing associations between traits, genetic variation, and carbon flux post hoc, the researchers plan to conduct a complementary de novo quantitative genetics study of trait variation and physiology, with the intent of linking both to carbon fluxes mediated by individual plants. Establishing such mechanistic links can improve parameterization of a mechanistic model of C cycling in coastal marshes, enabling a more thorough characterization of ecosystem-level consequences of organismal evolution. Findings from this project can illustrate whether organismal evolution is an important determinant of how ecosystems function and offer new insights about how global change can directly and indirectly alter ecosystems.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.