EAR-PF: Resolving the multi-scale hydraulics of shallow overland flows on patchily-vegetated hillslopes: towards a simple predictive framework

Octavia V. Crompton博士被授予NSF地球科学博士后奖学金，以开发工具，预测在强降雨事件期间从裸露土壤到植被区的地表流的再分配。这种再分配维持了年降雨量不足以支持植物生长的地区的生态系统。 目前，这种水再分配只能使用复杂和计算要求高的数值模型来预测。Crompton博士的研究将通过将小尺度上的水文过程与山坡结果联系起来来简化这些预测，使用裸露和植被覆盖的空间格局作为升级的基础。除了深入了解旱地景观中的地表水流物理学之外，这项研究还将发展土地管理者和生态学家评估景观脆弱性和设计可行的恢复战略所需的基本科学知识。 Crompton博士将在她的博士后研究期间由杜克大学的Gabriel Katul教授以及意大利都灵理工大学的Davide Poggi和Constantino Manes教授指导。 在杜克大学期间，克朗普顿博士将与杜克大学环境科学暑期项目合作，向STEM中代表性不足的群体的学生教授环境科学。 为了扩大定量环境科学的参与，克朗普顿博士将开发和教授环境过程的计算建模课程，补充该计划现有的基于实地的学习方法。这项研究有几个目标：首先，一系列水槽实验将解决非常浅（3厘米深）的物理不确定性，渗透流通过植被斑块。这将产生一些对这些流动的第一次实验性处理，并使人们能够对物理学有新的理解。 其次，圣维南方程的基础上的建模框架将被用来高档物理从植被斑块到山坡尺度，占空间异质性。 最后，减少复杂性模型，来自空间平均和分析近似的流量，将开发预测山坡规模的水文结果，并使用水槽实验测试其预测。由此产生的工具将改进与旱地恢复、补救和保护有关的预测，使人们能够明确地描述风暴内水文过程的影响。这一项目的更广泛影响将包括更好地了解旱地退化问题，旱地退化具有重大的社会和环境后果，影响到全球10%至20%的旱地，影响到约15亿人。该项目由地球科学部的水文科学项目资助。该奖项反映了NSF的法定使命，并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，被认为值得支持。

Dr. Octavia V. Crompton has been awarded an NSF Earth Sciences Postdoctoral Fellowship to develop tools that predict the redistribution of surface flow from bare soil to vegetated areas during intense rainfall events. This redistribution maintains ecosystems in regions where annual rainfall alone is insufficient to support plant growth. At present, this water redistribution can only be predicted using complex and computationally demanding numerical models. Dr. Crompton’s research will simplify these predictions by linking hydrological processes on small scales to hillslope-outcomes using the spatial pattern of bare and vegetated sites as a basis for upscaling. In addition to providing insights into the physics of overland flow in dryland landscapes, the study will develop basic scientific knowledge needed by land managers and ecologists to assess landscape vulnerability and design viable restoration strategies. Dr. Crompton will be mentored during her postdoctoral research by Professor Gabriel Katul at Duke University, and Professors Davide Poggi and Constantino Manes at Turin Polytechnical University, Italy. While at Duke University, Dr. Crompton will partner with the Duke University Environmental Science Summer Program to teach environmental science to students from underrepresented groups in STEM. Aiming to broaden participation in quantitative environmental sciences, Dr. Crompton will develop and teach a curriculum on computational modeling of environmental processes, complementing the program's existing field-based learning approach. The research has several objectives: First, a series of flume experiments will resolve uncertainties regarding the physics of very shallow ( 3 cm deep), infiltrating flows through vegetation patches. This will generate some of the first experimental treatments of these flows, and enable new understanding of the physics. Second, a modeling framework based on the Saint-Venant equations will be used to upscale physics from vegetation patch to hillslope scales, accounting for spatial heterogeneity. Finally, reduced complexity models, derived from spatial averaging and analytical approximations to the flow, will be developed to predict hillslope-scale hydrological outcomes, and their predictions tested using flume experiments. The resulting tools will improve predictions relevant to dryland restoration, remediation and conservation, by enabling explicit description of the effects of within-storm hydrologic processes. Broader impacts of this project will include a better understanding of dryland degradation, which has large social and environmental consequences, affecting 10 to 20% of global drylands and impacting approximately 1.5 billion people. This project was funded by the Hydrological Science program in the Earth Science division.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.