Hydromorphological attributes for all Australian river reaches derived from Landsat dynamic inundation remote sensing

摘要

Hydromorphological attributes such as flow width, waterextent, and gradient play an important role in river hydrological,biogeochemical, and ecological processes and can help to predict riverconveyance capacity, discharge, and flow routing. While there are some riverwidth datasets at global or regional scales, they do not consider temporalvariation in river width and do not cover all Australian rivers. We combineddetailed mapping of 1.4?million river reaches across the Australiancontinent with inundation frequency mapping from 27 years of Landsatobservations. From these, the average flow width at different recurrencefrequencies was calculated for all reaches, having a combined length of 3.3?millionkm. A parameter γ was proposed to describe the shape of thefrequency–width relationship and can be used to classify reaches by thedegree to which flow regime tends towards permanent, frequent, intermittent,or ephemeral. Conventional scaling rules relating river width to gradient andcontributing catchment area and discharge were investigated, demonstratingthat such rules capture relatively little of the real-world variability.Uncertainties mainly occur in multi-channel reaches and reaches withunconnected water bodies. The calculated reach attributes are easilycombined with the river vector data in a GIS, which should be useful forresearch and practical applications such as water resource management,aquatic habitat enhancement, and river engineering and management. Thedataset is available at https://doi.org/10.25914/5c637a7449353 (Hou et al.,?2019).