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包括海滩、三角洲和沼泽在内的沿海地貌。世界各地许多河流的河流每年排出的泥沙量都有测量，但北冰洋河流泥沙负荷的数据仍然很少，这主要是因为冬季和春季的“解体”季节(大块冰块崩塌并向下游流动，通常伴随着高流量的河流)无法获得。研究界还面临着传感器成本的挑战，传感器太有价值，不能大量部署，也不能在危险的冰盖和分裂季节部署。这项研究将吸引当地阿拉斯加土著学校的学生参与该项目的数据收集，并为早期职业女性和学生提供支持。在该项目中，将利用最近开发的“DIY”光学反向散射传感器来改进对北极河流沉积物通量的测量。这些传感器的制造成本不到商业传感器成本的10%，在这个项目中，它们将被扩展到包括数据记录和独立于传感器的电源，以及卫星启用的数据传输。这些发展将允许传感器在夏季、秋季和冬季部署在亚肯色州费尔班克斯附近的塔纳纳河上，以便在三个季节限制沉积物浓度。无人机部署将在春季分手期间进行，以完成四季的测量。为了更好地了解年泥沙负荷，将通过调查河流流速和模拟河流泥沙输移来补充部署。最终目的是为整个北极(及更远地区)的河流沉积物测量提供一个工具。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.