Collaborative Research: Sediment fluxes in boreal rivers: determining relative seasonal loads and expanding long-term monitoring capability

沉积物由河流输送到全球海洋，在那里它们有助于形成海岸地貌，包括海滩、三角洲和沼泽。每年河流排出的泥沙量已经对世界各地的许多河流进行了测量，但北极河流泥沙负荷的数据仍然很少，这主要是由于冬季和春季“破裂”季节（当大块冰破裂并向下游移动时，通常与河流的高流量同时发生）难以接近。研究界还面临着传感器成本的挑战，这些传感器太有价值了，不能大量部署，也不能在危险的冰雪覆盖和破裂季节部署。这项研究将让当地阿拉斯加原住民学校的学生参与项目的数据收集，并为早期职业女性和学生提供支持。在这个项目中，将利用最近开发的“自己动手”光学后向散射传感器来改进北极河流沉积物通量的测量。这些传感器的成本不到商用传感器的10%，在这个项目中，它们将扩展到包括数据记录和与传感器分离的电源，以及卫星启用的数据传输。这些发展将允许传感器在夏季、秋季和冬季部署在AK州费尔班克斯附近的Tanana河上，以限制三个季节的沉积物浓度。无人机部署将在春季分手期间进行，以完成四个季节的测量。部署工作还将辅以对河流流速的调查和对河流泥沙输送的模拟，以便更好地了解年泥沙负荷。最终目的是为整个北极地区（及其他地区）的河流沉积物测量提供一种工具。该奖项反映了美国国家科学基金会的法定使命，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。

Sediments are transported by rivers to global oceans where they help form coastal landforms including beaches, deltas, and marshes. The amount of sediment discharged by rivers annually has been measured for numerous rivers worldwide, but data for Arctic river sediment loads remains sparse largely due to inaccessibility during winter and the springtime “breakup” season (when large blocks of ice fail and move downstream, typically in conjunction with high river flow). The research community is also challenged by the costs of sensors, which are too valuable to deploy in large numbers or during risky ice-covered and breakup seasons. The research will engage local Alaska Native school students in the data collection for the project and supports early career women and students.In this project, a recently developed “do-it-yourself” optical backscatter sensor will be leveraged in order to make improved measurements of Arctic fluvial sediment fluxes. These sensors can be built for less than 10% of the cost of commercial sensors, and in this project they will be expanded to include data logging and power that is separate from the sensor, as well as satellite-enabled data transmission. These developments will allow sensor deployments in summer, fall, and winter seasons on the Tanana River near Fairbanks, AK in order to constrain sediment concentrations in three seasons. Drone-based deployments will be conducted during spring breakup to complete the four seasons of measurements. Deployments will be complemented by surveys of river velocity and modeling of fluvial sediment transport in order to better understand annual sediment loads. The ultimate aim is to provide a tool for fluvial sediment measurements across the Arctic (and beyond).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.