MTM 1: The sandy beach microbiome: physical, chemical and biological controls on diversity and function

沙滩占世界未冻海岸线的很大一部分，它们正受到海平面上升的严重威胁。它们提供重要的生态系统服务，包括水过滤和养分循环。这些过程是由一群微生物共同控制的，这些微生物被称为海滩地下的微生物群。虽然我们知道微生物组活性在这些系统中的重要性，但在这种环境中表征微生物群落的研究有限。该项目的目标是表征海滩地下微生物群，并研究控制其结构和功能的环境因素。这一目标将通过下一代测序方法实现，这些方法可以从DNA和RNA序列中提供大量的遗传信息。这个项目的成功完成将促进不同科学领域的知识和理解，包括环境微生物学、生态学和环境工程与科学。拟议的工作将通过进一步了解海滩提供的生态系统服务而造福社会，这是了解海平面上升对环境影响的关键信息。通过让来自不同背景的大学生参与研究，将增加美国STEM劳动力的多样性。与小学教师合作，为学龄儿童创建关于细菌的学习模块，将进一步造福社会。研究小组亦会在实地工作期间向公众宣传海滩生态系统，并与政府官员就海平面上升问题进行接触。陡峭的空间物理化学梯度和大的时间变化使沙质海滩地下河口成为一个理想的研究系统，可以集中研究海岸环境中微生物群结构和功能的规律。这将通过1)表征地下河口的微生物组，2)研究控制沙滩微生物组动态的机制，以及3)评估微生物通过沙子运输的迁移和对孔隙水化学变化的局部适应来实现。这项研究将采用最先进的扩增子测序、宏基因组学和宏转录组学以及水文学和生物地球化学的方法。该研究通过进一步了解海滩在生物地球化学循环方面提供的生态系统服务，使社会受益。由于海滩受到海平面上升的威胁，这项工作对于全面预测海平面上升对地球的影响至关重要。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。

Sandy beaches represent a large fraction of the world’s unfrozen shoreline and they are under serious threat from sea level rise. They provide important ecosystem services including water filtration and nutrient cycling. These processes are controlled by a community of microorganisms working together called a microbiome in the beach subsurface. While we know the importance of microbiome activity in these systems, there are limited studies that characterize the microbial community in this environment. The goal of this project is to characterize the microbiome in the beach subsurface and investigate the environmental factors that control its structure and function. This goal will be achieved using next generation sequencing methods that provide vast amounts of genetic information from DNA and RNA sequences. Successful completion of this project will advance knowledge and understanding across different scientific fields including environmental microbiology, ecology, and environmental engineering and science. The proposed work will benefit society by furthering the understanding of the ecosystem services provided by beaches, information critical to understanding the impact of sea level rise on the environment. The diversity of the Nation’s STEM workforce will be increased by engaging college students from diverse backgrounds in the research. Further benefits to society will result from teaming with elementary school teachers to create learning modules on bacteria for school-aged children. The research team will also conduct outreach to the public during field work to educate them about the beach ecosystem and engage government officials on the issue of sea level rise.The steep spatial physicochemical gradients and large temporal variation make the subterranean estuary of sandy beaches an ideal study system to focus on the goal of identifying the rules governing microbiome structure and function in coastal environments. This will be achieved by i) characterizing the microbiome in the subterranean estuary, ii) investigating the mechanisms controlling sandy beach microbiome dynamics, and iii) assessing microbial immigration via transport through the sands and local adaptation to changes in porewater chemistry. The research will employ state-of-the-science amplicon sequencing, metagenomics, and metatranscriptomics together with methods from hydrology and biogeochemistry. The research benefits society by furthering the understanding of the ecosystem services provided by beaches in terms of biogeochemical cycling. As beaches are threatened by sea level rise, this work is essential to fully anticipate the effects of sea level rise on the planet.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.