Postdoctoral Fellowship: EAR-PF: Feedbacks Between Controls of Stream Dry-Down Responses at the Rain-Snow Transition

博士后奖学金：EAR-PF：雨雪转变时河流干涸响应控制之间的反馈

• 批准号: 2305601
• 负责人: Maggi Kraft
• 金额: $ 18万
• 依托单位: Kraft, Maggi A
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2305601&HistoricalAwards=false
• 关键词: Postdoctoral; Fellowship; EAR; PF; Feedbacks

Dr. Maggi Kraft has been awarded an NSF Earth Sciences Postdoctoral Fellowship to carry out research and professional development activities under the mentorship of Dr. Sarah Godsey at Idaho State University. The western United States relies on snow for water resources. In the same region, the majority of streams fed by snowmelt and rain are non-perennial with streamflow disappearing for at least a portion of the year. Warming global temperatures are shifting the precipitation phase from snow to rain, but the impacts of shifting snowfall fraction in non-perennial streams are not clear. This research will merge concepts of snowmelt processes, vegetation dynamics, and soil properties across three watersheds spanning the rain-snow transition to understand how precipitation phase affects stream wetting and drying. These interactions are particularly important in controlling streamflow responses across the rain-snow transition where vegetation, snow, and soils are interrelated and sensitive to changing temperatures. While these concepts have been evaluated in a piecewise manner, they have not yet been integrated to allow us to accurately predict non-perennial streamflow response to changing snow inputs. This research will advance the science of non-perennial stream ecosystems and provide relevant information for managing natural resources. Additionally, this project will develop two education and outreach opportunities via developing and leading a workshop focused on the analysis of streamflow presence-absence data and mentoring an undergraduate student to develop, implement and present an interdisciplinary research project. Non-perennial streamflow response to shifts in snow represents a fundamental gap in our understanding of hydrologic behavior. Watersheds spanning the rain-snow transition, where precipitation shifts phase between snow and rain, provide an ideal location to study streamflow response to the shifting precipitation phase. Across the rain-snow transition feedbacks between vegetation, snow, and soil are interrelated thus, evaluation of coupled observations is needed to accurately predict streamflow response to changing snow water availability. However, there is a lack of integrated studies linking daily signals of snowmelt, transpiration, and soil moisture in non-perennial watersheds. The focus of this research is to study the response of non-perennial stream dry-down and wet-up to interactions between snow, rain, vegetation, and soils. This research will be carried out in three watersheds spanning the rain-snow transition in the semi-arid western U.S. using measurements of snow depth, sap flux, stream water presence-absence, soil moisture, and high-resolution satellite imagery. The satellite-derived and ground-based snowmelt, transpiration, and soil moisture observations will be compared to the annual and diel stream wet-dry cycle response. High-resolution soil depth maps will be created to evaluate how soil water capacity, snow storage, and vegetation modulate rain or snow water inputs and non-perennial streamflow. This research will advance the science of non-perennial stream ecosystems and provide relevant information for managing natural resources.This project is jointly funded by the Division of Earth Science Postdoctoral Fellowship Program and the Established Program to Stimulate Competitive Research (EPSCoR).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.

Maggi Kraft博士被授予NSF地球科学博士后研究金，以在爱达荷州立大学的Sarah Godsey博士的指导下进行研究和专业发展活动。美国西部依靠雪来提供水资源。在同一地区，大多数由融雪和雨水喂养的溪流是非周期性的，流量流消失了至少一部分。变暖的全球温度将降水阶段从降雪转移到雨水，但是在非周期流中降雪量的影响尚不清楚。这项研究将融合三个跨越雨水过渡的分水岭的融雪过程，植被动力学和土壤特性的概念，以了解降水阶段如何影响溪流润湿和干燥。这些相互作用在控制雨水转变的水流响应中尤其重要，在雨水转变中，植被，雪和土壤与温度变化相互关联并敏感。尽管这些概念已经以分段的方式进行了评估，但尚未集成它们，以使我们能够准确预测对变化雪的输入的非每年流量响应。这项研究将推进非每年的流生态系统的科学，并为管理自然资源提供相关信息。此外，该项目将通过开发和领导着一个专注于分析流量存在 - 缺乏数据的研讨会，并指导本科生开发，实施和提出一个跨学科研究项目，从而开发两个教育和推广机会。对雪的转变的非每年流量反应代表了我们对水文行为的理解的根本差距。跨越雨水转变的分水岭在雪和雨之间移动相位，为研究流量降水阶段的响应提供了理想的位置。因此，在植被，雪和土壤之间的雨水转变反馈中，需要评估耦合观测值，以准确预测流量水流的响应量。但是，缺乏连接非周期分水岭融雪，蒸腾和土壤水分的每日信号的综合研究。这项研究的重点是研究非每年的溪流干燥和湿的响应对雪，雨，植被和土壤之间的相互作用。这项研究将在美国西部半干旱西部的三个流域中进行，使用雪深，SAP通量，溪流水存在 - 少量，土壤水分和高分辨率卫星图像进行测量。将卫星来源和地面融雪，蒸腾和土壤水分观测结果与年度和DIEL流湿干燥循环响应进行比较。将创建高分辨率的土壤深度图，以评估土壤水的能力，积雪和植被如何调节雨或雪水输入和非每年的流量。这项研究将推进非周期流生态系统的科学，并提供有关管理自然资源的相关信息。本项目由地球科学科学博士后奖学金计划和既定计划刺激竞争性研究（EPSCOR）共同资助。该奖项通过评估了NSF的法规委员会的支持，该奖项反映了对概念的支持。