CMG Collaborative Research: Envirodynamics on River Networks

CMG 合作研究：河网环境动力学

• 批准号: 0934628
• 负责人: Efi Foufoula-Georgiou
• 金额: $ 13.8万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0934628&HistoricalAwards=false
• 关键词: CMG; Collaborative; Research; Envirodynamics; River

The topology of river networks has been extensively studied over the past decades using the suite of quantitative methods developed in the pioneering works of Horton, Strahler, Shreve, and Tokunaga. As a result, stream-ordering schemes and statistical self-similarity concepts have been explored to a considerable extent in hydrologic and geomorphologic sciences and have penetrated other areas of natural sciences. At the same time, questions related to how the static topology of a river network affects the dynamical processes operating on this network have been studied to a considerably lesser degree, while the impact of such processes is of the greatest interest from environmental, economic, and societal points of view. This project maintains a sustained research effort focused on environmental transport along river networks, in particular, and dynamic processes on hierarchical branching structures, in general. The main goal is to develop a theoretical and modeling framework that will facilitate predictive understanding of the relationships between the geometry of a network and dynamic processes that operate on it. The analytic methods to be developed and applied in the project arise from the theories of hierarchical aggregation and complex networks. The proposed transport modeling is based on the mathematical theory of Boolean delay equations (BDEs), a framework especially tailored for the mathematical modeling of systems that exhibit thresholds, multiple feedbacks and distinct time delays. The BDE modeling will provide a flexible basis for a preliminary assessment of land-use and climate change effects on resource attributes of a river system, including sediment grain size distribution, algae production and transport, nutrient loading, and fish population. It will also constitute a simple ?platform? for testing hypotheses and guiding further data collection efforts for improved prediction under uncertainty. The project will adapt concepts and tools from other disciplines, mainly dynamical and complex systems, to earth-surface research. The proposed study opens a new direction in earth-surface modeling, focused on environmental transport on river networks. The intellectual merit of this project resides in the novel mathematical, modeling, and data exploration approaches, put forward by an interdisciplinary team toward predictive understanding of environmental dynamics on river networks. The critical societal and economic importance of network dynamic problems? in the geosciences and other areas of the physical and life sciences?adds substantially to the proposal?s intellectual merit. The project will result in better predictive understanding of environmental fluxes including precipitation, sediment bedload, nutrients, pollutants, etc., and provide new insight into rivers? habitat structure and food webs. The project will impact other science areas that involve network dynamics and hierarchical aggregation, including gene interactions, social networks, spread of diseases, and Internet security. The new results will be achieved by further developing a novel theoretical concept of dynamic networks, integrating this concept into concrete applications, and developing corresponding numerical models. The project PIs are actively involved in promoting interactions between mathematicians, physicists and researchers in geosciences and will further strengthen such interactions within this project. The collaborative and cross-disciplinary approach of this project makes it an ideal training ground for graduate students, post-docs and young scientists.

在过去的几十年中，使用了霍顿，斯特拉勒，什里夫和托库纳加开发的一系列定量方法，对河网络的拓扑进行了广泛的研究。结果，在水文和地貌科学中，已经在很大程度上探讨了流订购方案和统计自相似性概念，并渗透了自然科学的其他领域。同时，与河网络的静态拓扑有关如何影响在该网络上运行的动态过程的问题的程度大大降低，而这种过程的影响是环境，经济和社会观点的最大兴趣。该项目一般而言，该项目尤其是沿着河网络的环境运输以及整体分支结构的动态流程进行了持续的研究工作。主要目标是开发一个理论和建模框架，以促进对网络几何形状与在其上运行的动态过程之间的关系的预测理解。要在项目中开发和应用的分析方法来自层次聚合和复杂网络的理论。所提出的传输建模基于布尔延迟方程（BDES）的数学理论，该框架尤其是针对表现出阈值，多个反馈和不同时间延迟的系统的数学建模量身定制的。 BDE建模将为对土地利用和气候变化对河流系统资源属性的影响的初步评估提供灵活的基础，包括沉积物晶粒尺寸分布，藻类生产和运输，营养量和鱼类种群。这也将构成一个简单的平台？用于测试假设并指导进一步的数据收集工作，以改善不确定性的预测。该项目将从其他学科（主要是动态和复杂系统）中调整概念和工具，以适应地面地面研究。拟议的研究开辟了一个新的方向，以地球地面建模为重点是河网络上的环境运输。该项目的智力优点在于，跨学科团队提出的新型数学，建模和数据探索方法，旨在预测对河网络环境动态的理解。网络动态问题的关键社会和经济重要性？在地球科学和身体和生命科学的其他领域，大大增加了提议的知识分子。该项目将对环境通量进行更好的预测理解，包括降水，沉积物床，营养素，污染物等，并为河流提供新的见解？栖息地结构和食物网。该项目将影响涉及网络动态和分层聚集的其他科学领域，包括基因相互作用，社交网络，疾病传播和互联网安全。新的结果将通过进一步发展动态网络的新理论概念，将此概念整合到具体应用中，并开发相应的数值模型来实现。 PIS PIS积极参与促进地球科学方面的数学家，物理学家和研究人员之间的相互作用，并将进一步加强该项目中的这种相互作用。该项目的协作和跨学科方法使其成为研究生，博士后和年轻科学家的理想培训场。