CAREER: Alluvial-river dynamics through watershed networks

职业：流域网络中的冲积河流动态

基本信息

批准号：
1944782
负责人：
Andrew Wickert
金额：
$ 62.23万
依托单位：
University of Minnesota-Twin Cities
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-07-01 至 2025-06-30
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1944782&HistoricalAwards=false
关键词：
CAREER Alluvial river dynamics through

项目摘要

Rivers and their tributaries form networks that integrate the far reaches of Earth's landscapes, linking our homes, farms, cities, and wilderness areas. These rivers are ever-changing, sometimes near-imperceptibly and sometimes dramatically adjusting their forms to carry the water and sediment supplied by rainfall, snow/ice melt, and erosion of the surrounding landscape. Both natural and human activities can alter the balance of water and sediment entering rivers, causing them to erode downwards into their beds when water supply outweighs sediment supply, or to deposit sediments and raise the level of their beds when sediment supply increases beyond what the water can carry. Wickert and his team will develop a theory to predict these river-system changes, and incorporate it into a computer model that includes rainfall and runoff, lakes and wetlands, and processes that shape rivers. They will test this theory and model using data from rivers in Minnesota, USA, and Salta, Argentina. These rivers' bed elevations have changed by tens to hundreds of meters during past glacial cycles and by several meters over the past 200 years in response to changing climate and land use. Controlled experiments on small-scale rivers conducted at the Saint Anthony Falls Laboratory will supplement these field-based tests. The proposed outcome of this work is an efficient, physics-based, predictive model to simulate river-network evolution in response to climate and land-use change. The project will train undergraduate students, graduate students, and postdoctoral scholars. The team will work with the Ojibwe people to broaden participation in science.Wickert and his group will develop and test theory and models to simulate river-network response to changes in water and sediment supply. They will codify river-tributary networks into mathematical networks that additionally incorporate valleys, lakes, and the surrounding hillslopes. They will then couple and solve equations describing alluvial-river dynamics across these networks to predict the complex response of rivers to external perturbations. These equations will underlie a new numerical model, to be tested against field and laboratory data and driven by records and simulations of sediment inputs and water discharge. This model will enable us to rapidly simulate alluvial-river response to drivers of geomorphic change, thereby improving our ability to both reconstruct past river dynamics and forecast the impacts of environmental change on rivers into the future.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.

河流及其支流形成了将地球景观范围融合在一起的网络，将我们的房屋，农场，城市和荒野区域联系起来。这些河流在不断变化，有时几乎刻板地，有时会大大调整其形式，以携带降雨，雪/冰融化以及周围景观的侵蚀所提供的水和沉积物。自然和人类活动都会改变水和沉积物进入河流的平衡，使其在供水量超过沉积物供应量或沉积沉积物时向下侵蚀到床上，当沉积物供应量增加到水可以携带时，它们的床位水平。威克特（Wickert）和他的团队将开发一种预测这些河流系统变化的理论，并将其纳入包括降雨和径流，湖泊和湿地在内的计算机模型，以及塑造河流的过程。他们将使用来自明尼苏达州河流和阿根廷萨尔塔的河流的数据来测试这一理论和模型。在过去的200年中，这些河流的床高度在过去的200年中变成了数十万米，并且在过去的200年中，由于气候和土地利用的变化而变化了几米。在圣安东尼瀑布实验室进行的小规模河流的受控实验将补充这些基于现场的测试。这项工作的拟议结果是一个有效的，基于物理学的预测模型，以响应气候和土地利用变化来模拟河流网络的演变。该项目将培训本科生，研究生和博士后学者。该团队将与Ojibwe人民合作，以扩大对科学的参与。Wickert及其小组将开发和测试理论和模型，以模拟河流网络对水和沉积物供应变化的反应。他们将将河流网络编纂成数学网络，这些网络还结合了山谷，湖泊和周围的山坡。然后，他们将对这些网络中描述冲积向摩托车动态的方程式进行求助，以预测河流对外部扰动的复杂响应。这些方程将是一个新的数值模型的基础，该模型将针对现场和实验室数据进行测试，并由沉积物输入和水排放的记录和模拟驱动。该模型将使我们能够快速模拟对地貌变化驱动因素的冲积向反应，从而提高我们重建过去的河流动力学的能力，并预测环境变化对河流对未来的影响。这项奖项反映了NSF的法规使命，并被认为是通过基金会的知识效果和广泛的Impactia的评估来进行评估，并值得通过评估来进行评估。