Coarse bed load transport is a crucial process in river morphodynamics but is difficult to monitor in mountain streams. Here we present a new sediment transport data set obtained from 2 years of field‐based monitoring (2014–2015) at the Estero Morales, a high‐gradient stream in the central Chilean Andes. This stream features step‐pool bed geometry and a glacier‐fed hydrologic regime characterized by abrupt daily fluctuations in discharge. Bed load was monitored directly using Bunte samplers and by surveying the mobility of passive integrated transponder (PIT) tags. We used the competence method to quantify the effective slope, which is the fraction of the topographical slope responsible for bed load transport. This accounts for only 10% of the topographical slope, confirming that most of the energy is dissipated on macroroughness elements. We used the displacement lengths of PIT tags to analyze displacement lengths and virtual velocity of a wide range of tracer sizes (38–415 mm). Bed load transport in the Estero Morales shown to be size‐selective, and the distance between steps influences the displacement lengths of PIT tags. Displacement lengths were also used to derive the statistics of flight distances and resting times. Our results show that the average length of flight scales inversely to grain size. This contradicts Einstein's conjecture about the linear relationship between grain size and intervals between resting periods in a steep step‐pool stream in ordinary flood conditions.

中文翻译：

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控制冰川进给的山间溪流中粗运动的质点运动和静止时间

粗河床输水是河流形态动力学的关键过程，但在山streams中很难监测。在这里，我们介绍了从智利安第斯山脉中部的高梯度河流埃斯特罗·莫拉莱斯（Estero Morales）进行了为期2年的实地监测（2014-2015）获得的新沉积物传输数据集。这条河的特点是阶跃池床的几何形状和冰川蓄水的水文状况，其特征是每天的排放量突然波动。使用Bunte采样器并通过调查无源集成应答器（PIT）标签的移动性，可以直接监测床负载。我们使用能力方法来量化有效坡度，该有效坡度是负责床载运输的地形坡度的一部分。这仅占地形坡度的10％，这证实了大部分能量都在宏观粗糙度元素上耗散了。我们使用了PIT标签的位移长度来分析各种示踪剂尺寸（38–415 mm）的位移长度和虚拟速度。埃斯特罗·莫拉莱斯（Estero Morales）的床层负载运输具有选择性，步距之间的距离会影响PIT标签的位移长度。位移长度还用于得出飞行距离和静止时间的统计数据。我们的结果表明，平均飞行长度与晶粒尺寸成反比。这与爱因斯坦关于在正常洪水条件下陡峭的阶梯状水流中晶粒尺寸与静止时间间隔之间的线性关系的推测相矛盾。埃斯特罗·莫拉莱斯（Estero Morales）的床层负载运输具有选择性，步距之间的距离会影响PIT标签的位移长度。位移长度还用于得出飞行距离和静止时间的统计数据。我们的结果表明，平均飞行长度与晶粒尺寸成反比。这与爱因斯坦关于在正常洪水条件下陡峭的阶梯状水流中晶粒尺寸与静止时间间隔之间的线性关系的推测相矛盾。埃斯特罗·莫拉莱斯（Estero Morales）的床层负载运输具有选择性，步距之间的距离会影响PIT标签的位移长度。位移长度还用于得出飞行距离和静止时间的统计数据。我们的结果表明，平均飞行长度与晶粒尺寸成反比。这与爱因斯坦关于在正常洪水条件下陡峭的阶梯状水流中晶粒尺寸与静止时间间隔之间的线性关系的推测相矛盾。