EAR-PF: Quantifying the effects of flow transience on sediment transport

EAR-PF：量化流动瞬变对沉积物输送的影响

• 批准号: 1349776
• 负责人: Colin Phillips
• 金额: $ 8.7万
• 依托单位: Phillips Colin B
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1349776&HistoricalAwards=false
• 关键词: EAR; PF; Quantifying; effects; flow

Dr. Colin Phillips has been awarded an NSF Earth Sciences Postdoctoral Fellowship to carry out a research and educational outreach plan at the University of Minnesota. He will investigate the process of gravel transport in response to transient and intermittent flooding. Gravel rivers represent the rate limiting step in the incision of mountains and also provide critical habitat and breeding grounds to numerous aquatic species. These experiments will form the basis for understanding how potential changes in climate and land use will affect gravel streams. In addition these experiments will provide a quantitative framework for stream managers regulating flow releases below dams and stream restoration projects. The results from these experiments will be turned into interactive online tools for stream restoration practitioners. Furthermore, the knowledge gained from this project will be transferred to young scientists through classes and experiments during the National Center for Earth Surface Dynamics 2 (NCED2) Summer Institute, and to future young scientists by collaborating with NCED2 REU students.A large majority of our understanding of gravel river dynamics comes from flume experiments under constant or slowly varying floods. Many of the theories developed under steady flow provide reasonable predictions of the dynamics of gravel rivers when averaged over numerous floods, however due to the stochastic nature of sediment transport it remains unclear whether these predictions break down due to flow unsteadiness or granular phenomena. Through the use of laboratory experiments he will test the relative importance of flood shape and sequence to determine how an unsteady flow drives sediment transport. This project will compare the dynamics of gravel transport at the particle level through the tracking of several populations of marked particles under a variety of single and sequences of flows of varying magnitude and duration, but equivalent impulse (time-integrated momentum above the threshold of particle motion).

科林·菲利普斯（Colin Phillips）博士已获得NSF地球科学博士后研究金，以在明尼苏达大学执行研究和教育外展计划。他将根据短暂和间歇性的洪水调查碎石运输过程。碎石河代表了山脉切口的限制步骤，还为许多水生物种提供了关键的栖息地和繁殖地。这些实验将构成理解气候和土地使用的潜在变化如何影响砾石流的基础。此外，这些实验将为流媒体管理者提供一个定量框架，以调节大坝和流恢复项目下方的流量释放。这些实验的结果将变成用于流恢复从业者的交互式在线工具。此外，该项目所获得的知识将通过国家地面动力学2（NCED2）夏季研究所的课程和实验转移给年轻科学家，并通过与NCED2 REU学生合作，通过与NCED2 REU学生合作，将未来的年轻科学家转移到未来的年轻科学家中。我们对Gravel River Dynamigs的大部分理解来自不断或缓慢变化的洪水。在稳定流动下开发的许多理论在平均众多洪水中平均提供了合理的预测砾石河的动力学，但是由于沉积物的随机性质，尚不清楚这些预测是否由于流动不稳定或颗粒状现象而崩溃。通过使用实验室实验，他将测试洪水形状和序列的相对重要性，以确定不稳定的流动如何驱动沉积物的运输。该项目将通过在各种不同的幅度和持续时间的单一和序列下对几个标记粒子种群进行跟踪，以比较颗粒水平的砾石传输的动力学，但要等于脉冲（粒子运动阈值以上的时间融合动量）。