Collaborative Research: An Inter-disciplinary Approach to Constraining Paleo-geomorphic Responses to the Eocene-Oligocene Hothouse to Icehouse Transition

河流是国家的动脉，是水源、娱乐和商业的重要来源。他们也是格局变化的风向标。然而，对国家利益至关重要的一个问题是，河流系统如何应对重大环境变化。预测环境条件的变化如何影响河流过程，如洪水和侵蚀，对于水资源管理至关重要。该项目使用过去的知识作为关键，通过研究内布拉斯加州西部和南达科他州一个古老河流网络中约3500万年前的沉积物来更好地了解现在的情况，以量化过去降水、植被和温度的变化如何导致河流流量和洪水规模的变化。这些数据与水力学模型相结合，将提高我们预测河流洪水、泥沙输送和集水区演变的能力。这项工作的结果将对理解、模拟和规划未来的河流系统变化产生深远的影响。这项研究的三个更广泛的关键影响包括：1)支持研究生和本科生发展跨学科专业知识；2)共享数据、方法和结果，作为开放获取平台上的教学数据集；3)为儿童提供科学推广模块，以探索三维岩石露头和计算模型中的动画。这项拟议研究的目标是重建北美西部始新世-渐新世过渡(EOT)期间古生物和生态系统动力学与环境变化的共同进化，EOT可能是过去6500万年来最大的气候状态变化。这将通过整合古气候的地球化学记录、河流运输和沉积的沉积学指标以及水文地貌模型来实现。为了实现项目目标，一个由地球化学家、沉积学家和水利工程师组成的团队将开发一种综合方法，以了解河流对环境变化的反应。这种跨学科方法的成功可以在利用现代和古代陆地地质档案来量化表现在水力学、地貌动力学和区域生态系统响应中的环境扰动方面提供范式转变。这一奖项反映了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。

Rivers are the arteries of the nation and are vital as sources of water and recreation, and avenues of commerce. They are also bellwethers for change in the landscape. However, a question of fundamental importance for national interest is how river systems respond to major environmental changes. Predicting how changes in environmental conditions affect river processes, such as flooding and erosion, is critical for water resource management. This project uses knowledge of the past as a key to better inform the present through examining ~35 million year old sediments from an ancient river network in western Nebraska and South Dakota to quantify how changes in precipitation, vegetation and temperature in the past caused changes in river discharge and flood magnitude. These data, integrated with hydraulic models, will improve our ability to predict how rivers flood, sediment is transported and catchments evolve. Results of this work will have far reaching implications for understanding, modeling and planning for changes to river systems in the future. Three key broader impacts of this study include: 1) support of graduate and undergraduate students to develop interdisciplinary expertise; 2) sharing of data, methods and results as teaching data-sets on open-access platforms; 3) science outreach modules for children to explore 3-dimensional rock outcrops and animations from computational models. The goal of the proposed research is to reconstruct the coevolution of paleoriver and ecosystems dynamics with environmental change in western North America during the Eocene-Oligocene transition (EOT), perhaps the largest climate state change of the last 65 million years. This will be accomplished by integrating geochemical records of paleoclimate, sedimentologic indicators of river transport and deposition, and hydraulic-geomorphic models. To achieve the project goals a team of geochemists, sedimentologists and hydraulic engineers will develop an integrated approach to understanding how rivers respond to environmental change. Success in this cross-disciplinary approach could provide a paradigm shift in utilizing modern and ancient terrestrial geologic archives to quantify environmental perturbations that manifest in the hydraulics, morphodynamics and regional ecosystem responses.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.