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，是至关重要的水源和娱乐，以及商业途径。他们也是景观变化的领头羊。然而，一个对国家利益至关重要的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洪水和侵蚀等河流过程，对于水资源管理至关重要。该项目利用过去的知识作为一个关键，通过检查内布拉斯加州西部和南达科他州的古代河流网络中约3500万年前的沉积物来更好地了解现在，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量级的变化。这些数据与水力模型相结合，将提高我们预测河流洪水，沉积物运输和集水区演变的能力。这项工作的结果将有深远的影响，理解，建模和规划的变化，河流系统在未来。这项研究的三个关键的更广泛的影响包括：1）支持研究生和本科生发展跨学科的专业知识; 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）科学外展模块，让孩子们探索三维岩石露头和动画计算模型。拟议研究的目标是重建古河流和生态系统动力学的共同进化与北美西部始新世-渐新世过渡（EOT）期间的环境变化，这可能是过去6500万年来最大的气候变化。这将通过整合古气候的地球化学记录、河流搬运和沉积的沉积学指标以及水力地貌模型来实现。为了实现该项目的目标，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，以了解河流如何对环境变化作出反应。这种跨学科方法的成功可以为利用现代和古代陆地地质档案量化水力学、形态动力学和区域生态系统响应中表现出来的环境扰动提供一种范式转变。该奖项反映了NSF的法定使命，并被认为值得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来支持。

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.