학술논문
“Process-based similarity” revealed by discharge-dependent relative submergence dynamics of thousands of large bed elements
Document Type
Electronic Resource
Author
Source
Earth Surface Processes and Landforms; vol 48, iss 5, 887-906; 0197-9337
Subject
Language
Abstract
Relative submergence of macroroughness elements such as boulders and bedrock outcrops, or large bed elements (LBEs), collectively, is a primary control on hydraulics and morphodynamics in steep, coarse-bedded rivers. However, in practice, the property is typically represented by singular, often reach- or cross-section-averaged values that mask bed-surface heterogeneity and joint distributions of local flow depths. By coupling sub-meter resolution two-dimensional (2D) hydrodynamic modeling with spatially explicit mapping of LBEs from a 13.2 km segment of a boulder-bedded mountain river, we present complete distributions of LBE relative submergences at multiple spatial scales and explore their dynamism across discharges. Through distribution fitting and statistical analysis of resultant discharge-dependent LBE relative submergence datasets, it was confirmed that segment- and reach-scale datasets exhibited similar statistical properties and were able to be drawn from the same type of distribution. Further, the rate at which statistical and parametric properties changed between discharge-dependent datasets were statistically equivalent between spatial domains, which we term “process-based similarity”. Commonality in distribution type and the uniform between discharge–scaling relationships suggest mutual self-organizing processes associated with the size-frequency distribution, spatial arrangement, and submergence of LBEs were present between most domains.