Tracing Fine Sediment Transport in Fluvial Systems Using Fallout Radionuclides

9814814 matisov尽管我们了解沉积物和沉积物结合的污染物的大致路径，但我们对它们通过排水网络和到达接收体的运输时间知之甚少。该项目的目标是开发一种创新但广泛适用的工具，以研究景观中细沉积物的侵蚀机制和细悬浮颗粒在渠道中的运输特性。具体来说，我们的目标是回答有关悬浮沉积物来源的问题（它是来自板蚀、细沟侵蚀、河岸侵蚀还是底部沉积物的再悬浮？）；流域细泥沙的输送比例（即从景观中被侵蚀并输送到接收水域的泥沙比例，或仅部分输送并停留在景观或河床中的泥沙比例）；新近从被土壤覆盖的景观中输送的悬浮沉积物与从河床中再悬浮沉积物的比例；细颗粒物的传输距离；颗粒的停留时间；还有从分水岭流出的细颗粒物。我们将采用我们开发的一种新技术，使用放射性沉降核素（7Be， 137Cs和210Pb）作为河流悬浮的细沉积物的示踪剂。这项为期两年的研究将集中在怀俄明州和蒙大拿州的黄石河流域。在第一年，我们将讨论追踪的动力学和积雪、土壤、底部沉积物和悬浮沉积物的放射性核素特征的表征。在第二年，我们将在一个融雪驱动的水文图中描述900公里范围内细沉积物的来源和运输。实验设计包括在排水网络的不同位置收集降水、土芯、洪泛平原沉积物、河道底部沉积物和悬浮沉积物样本；自然发生的短寿命（7Be）和较长寿命（137Cs 210 Pb）放射性沉降核素和其他重要的放射性核素标签（214 Bi, 40K）的样品的伽马能谱，这些放射性核素标签吸附在沉积物上，提供了不同时间尺度上沉积物运动的示踪剂；追踪1950年研究区内某高地源区排放的尾矿的移动情况；颗粒大小和浓度分析；以及波浪运动学和质量平衡建模。9814814 matisov尽管我们了解沉积物和沉积物结合的污染物的大致路径，但我们对它们通过排水网络和到达接收体的运输时间知之甚少。该项目的目标是开发一种创新但广泛适用的工具，以研究景观中细沉积物的侵蚀机制和细悬浮颗粒在渠道中的运输特性。具体来说，我们的目标是回答有关悬浮沉积物来源的问题（它是来自板蚀、细沟侵蚀、河岸侵蚀还是底部沉积物的再悬浮？）；流域细泥沙的输送比例（即从景观中被侵蚀并输送到接收水域的泥沙比例，或仅部分输送并停留在景观或河床中的泥沙比例）；新近从被土壤覆盖的景观中输送的悬浮沉积物与从河床中再悬浮沉积物的比例；细颗粒物的传输距离；颗粒的停留时间；还有从分水岭流出的细颗粒物。我们将采用我们开发的一种新技术，使用放射性沉降核素（'Be， 117CS和21opb）作为河流悬浮的细沉积物的示踪剂。这项为期两年的研究将集中在怀俄明州和蒙大拿州的黄石河流域。在第一年，我们将讨论追踪的动力学和积雪、土壤、底部沉积物和悬浮沉积物的放射性核素特征的表征。在第二年，我们将在一个融雪驱动的水文图中描述900公里范围内细沉积物的来源和运输。实验设计包括在排水网络的不同位置收集降水、土芯、洪泛平原沉积物、河道底部沉积物和悬浮沉积物样本；自然发生的短寿命（‘Be）和较长寿命（117 Cs anCf2 ’OPb）放射性沉降核素和其他重要的放射性核素标签（214 Bi, @K）的样品的伽马能谱，这些放射性核素标签吸附在沉积物上，提供了不同时间尺度上沉积物运动的示踪剂；追踪1950年研究区内某高地源区排放的尾矿的移动情况；颗粒大小和浓度分析；以及波浪运动学和质量平衡建模。

9814814MatisoffDespite our understanding of the gross paths taken by sediments and sediment-bound pollutants, we have a poor knowledge of the transit time for their passage through the drainage network and to receiving bodies. The goal of this project is to develop an innovative but broadly applicable tool to investigate the erosion mechanisms of fine sediment from the landscape and the transport characteristics of fine suspended particulates in channels. Specifically, we aim to answer questions on the the source of the suspended sediment (Is it from sheet erosion, rill erosion, bank erosion, or resuspension of bottom sediments?); the delivery ratios of fine sediment from the watershed (i.e., the proportion of sediment that is eroded from the landscape and delivered to the receiving waters or the proportion that is transported only part way and resides on the landscape or in the streambed); the proportions of suspended sediment that is newly delivered from the soil mantled landscape versus resuspended from the bed; the transit distance of fine particulates; the residence time of particulates; and the flux of fines from the watershed. We will employ a novel technique we have developed that uses fallout radionuclides ( 7Be , 137Cs, and 210Pb ) as tracers of fine sediments suspended by streamflow.The two-year study will be focused in the Yellowstone River watershed in Wyoming and Montana. During the first year we will address the kinetics of the tracing and the characterization of the radionuclide signature of the snowpack, soils, bottom sediment, and suspended sediment. During the second year we will characterize the sources and transport of fine sediment over a distance of 900 km during a snowmelt-driven hydrograph. The experimental design includes collection of precipitation, soil cores, floodplain sediment, channel bottom sediment, and suspended sediment samples at various locations in the drainage networks; gamma spectroscopy of samples for naturallyoccurring short-lived (7Be) and lonaer-lived ( 137Cs 210 Pb) fallout radionuclides and other important radionuclide tags (214 Bi, 40K) that adsorb to sediment providing tracers of sediment movement over different time scales; tracing the movement of mine tailings that were released from an upland source area in the study area in 1950; analyses of particle sizes and concentrations; and wave kinematic and mass balance modeling.9814814MatisoffDespite our understanding of the gross paths taken by sediments and sediment-bound pollutants, we have a poor knowledge of the transit time for their passage through the drainage network and to receiving bodies. The goal of this project is to develop an innovative but broadly applicable tool to investigate the erosion mechanisms of fine sediment from the landscape and the transport characteristics of fine suspended particulates in channels. Specifically, we aim to answer questions on the the source of the suspended sediment (Is it from sheet erosion, rill erosion, bank erosion, or resuspension of bottom sediments?); the delivery ratios of fine sediment from the watershed (i.e., the proportion of sediment that is eroded from the landscape and delivered to the receiving waters or the proportion that is transported only part way and resides on the landscape or in the streambed); the proportions of suspended sediment that is newly delivered from the soil mantled landscape versus resuspended from the bed; the transit distance of fine particulates; the residence time of particulates; and the flux of fines from the watershed. We will employ a novel technique we have developed that uses fallout radionuclides ('Be, 117CS , and 21 OPb) as tracers of fine sediments suspended by streamflow.The two-year study will be focused in the Yellowstone River watershed in Wyoming and Montana. During the first year we will address the kinetics of the tracing and the characterization of the radionuclide signature of the snowpack, soils, bottom sediment, and suspended sediment. During the second year we will characterize the sources and transport of fine sediment over a distance of 900 km during a snowmelt-driven hydrograph. The experimental design includes collection of precipitation, soil cores, floodplain sediment, channel bottom sediment, and suspended sediment samples at various locations in the drainage networks; gamma spectroscopy of samples for naturallyoccurring short-lived ('Be) and lonaer-lived (117 Cs anCf2 'OPb) fallout radionuclides and other important radionuclide tags (214 Bi, @K) that adsorb to sediment providing tracers of sediment movement over different time scales; tracing the movement of mine tailings that were released from an upland source area in the study area in 1950; analyses of particle sizes and concentrations; and wave kinematic and mass balance modeling.