Collaborative research:An Experimental Investigation of Morphodynamic Coupling between River Deltas and Marshes

河流三角洲与沼泽地貌动力学耦合的实验研究河流三角洲作为人口中心和基础设施枢纽，对社会具有重要意义。大多数河流三角洲都有大片的沼泽地，这些沼泽地是生物多样性的热点，多产的渔业，有效的风暴保护，并捕获和储存大量的碳。河流三角洲和沼泽作为海平面上升和沉积物输入的函数而生长和崩溃的过程是众所周知的。然而，人们对沼泽和三角洲如何相互作用缺乏基本的了解。沼泽和三角洲动态之间的反馈是否从根本上影响两者的行为？研究人员将建立实验室规模的三角洲受控制的环境条件，将与一个新开发的沼泽代理，模仿关键沼泽属性在缩小规模。这些实验将有助于揭示河流三角洲和沼泽在简单条件下如何在数百至数千年的时间尺度上相互作用，并提供对目前影响密西西比和其他全球河流三角洲的土地流失和沉降问题的深入了解。该项目将把实验广播到路易斯安那州的K-12教室，培训阿肯色州和杜兰大学的一组多样化的研究人员，并将结果转化为文章，通过社交媒体平台供公众消费。研究人员将研究河流三角洲和沼泽如何通过物理实验室实验相互作用，该实验将结合一种新的沼泽代理。这沼泽代理将被添加到三角洲实验后，基于规则的沉积模型的基础上不断发展的存款的当地海拔。这将首次使他们能够记录三角洲的内部动态是如何被覆盖许多三角洲平原的大片沼泽所增强的。通过与先前在没有沼泽的情况下进行的实验进行比较，他们将分离出地表动力学、压实沉降模式和沼泽-三角洲耦合的地层产物。在这项研究中开发的定量理论将有助于预测沼泽和三角洲的可持续性，在未来几十年，提高能力，解释他们的地层古环境记录。 研究将由一个多元化的团队（性别，种族和职业阶段）进行，包括本科生和研究生，并推广到K-12学生。该项目由地貌学和土地利用动力学计划以及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。

Experimental Investigation of Morphodynamic Coupling between River Deltas and MarshesRiver deltas are important to society as population centers and infrastructure hubs for hundreds of millions of people. Most river deltas host vast marshes that are biodiversity hotspots, productive fisheries, effective storm protection, and that capture and store significant amounts of carbon. The processes by which river deltas and marshes grow and collapse as a function of rising sea level and sediment input are well known in isolation. However, there is a fundamental lack of understanding of how marshes and deltas interact. Do feedbacks between marsh and delta dynamics fundamentally influence the behavior of both? The researchers will build laboratory scale deltas subject to controlled environmental conditions that will interact with a newly developed marsh proxy that mimics key marsh properties at a reduced scale. These experiments will help reveal how river deltas and marshes interact over hundred to thousand year timescales under simple conditions, and provide insight into the land loss and subsidence problems that are currently affecting the Mississippi and other global river deltas. The project will broadcast experiments into K-12 classrooms in Louisiana, train a diverse group of researchers at University of Arkansas and Tulane University, and translate results into articles designed for public consumption through social media platforms.The researchers will study how river deltas and marshes interact using physical laboratory experiments that will incorporate a novel marsh proxy. This marsh proxy will be added to deltaic experiments following a rule-based model of sedimentation based on the local elevation of the evolving deposit. For the first time, this will allow them to document how the internal dynamics of deltas are augmented by marshes that cover vast swaths of many delta plains. Through comparison to prior experiments that evolved in the absence of marshes, they will isolate surface dynamics, compactional subsidence patterns, and stratigraphic products of marsh-delta coupling. Quantitative theory developed in this study will aid prediction of marsh and deltas sustainability in the coming decades and enhance ability to interpret their strata for paleo-environmental records. Research will be conducted by a diverse team (in gender, ethnicity, and career stage) including undergraduate and graduate students, and outreach to K-12 students. This project is jointly funded by the Geomorphology and Land-Use Dynamics 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.