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

沉积物被河流运送到全球海洋，在那里它们帮助形成沿海地貌，包括海滩，三角洲和沼泽。对全世界许多河流每年排放的泥沙量进行了测量，但北极河流泥沙量的数据仍然很少，这主要是由于冬季和春季“崩解”季节（大块冰块崩解并向下游移动，通常与河流流量高有关）无法获得。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，无法大量部署，也无法在危险的冰盖和解体季节部署。这项研究将使阿拉斯加当地土著学校的学生参与该项目的数据收集工作，并支持早期职业妇女和学生，在该项目中，将利用最近开发的“自己动手”光学反向散射传感器，以改进对北极河流沉积物通量的测量。这些传感器的成本不到商业传感器的10%，在这个项目中，它们将被扩展到包括与传感器分离的数据记录和电源，以及卫星支持的数据传输。这些发展将允许传感器部署在夏季，秋季和冬季的塔纳纳河附近的费尔班克斯，AK，以限制泥沙浓度在三个季节。基于无人机的部署将在春季分手期间进行，以完成四个季节的测量。部署工作还将辅之以河流流速调查和河流沉积物输运建模，以便更好地了解年度沉积物负荷。最终目标是为整个北极地区（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。

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.