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Geometry and Topology of Estuary and Braided River Channel Networks Automatically Extracted From Topographic Data.

ABSTRACT: Automatic extraction of channel networks from topography in systems with multiple interconnected channels, like braided rivers and estuaries, remains a major challenge in hydrology and geomorphology. Representing channelized systems as networks provides a mathematical framework for analyzing transport and geomorphology. In this paper, we introduce a mathematically rigorous methodology and software for extracting channel network topology and geometry from digital elevation models (DEMs) and analyze such channel networks in estuaries and braided rivers. Channels are represented as network links, while channel confluences and bifurcations are represented as network nodes. We analyze and compare DEMs from the field and those generated by numerical modeling. We use a metric called the volume parameter that characterizes the volume of deposited material separating channels to quantify the volume of reworkable sediment deposited between links, which is a measure for the spatial scale associated with each network link. Scale asymmetry is observed in most links downstream of bifurcations, indicating geometric asymmetry and bifurcation stability. The length of links relative to system size scales with volume parameter value to the power of 0.24-0.35, while the number of links decreases and does not exhibit power law behavior. Link depth distributions indicate that the estuaries studied tend to organize around a deep main channel that exists at the largest scale while braided rivers have channel depths that are more evenly distributed across scales. The methods and results presented establish a benchmark for quantifying the topology and geometry of multichannel networks from DEMs with a new automatic extraction tool.

SUBMITTER: Hiatt M

PROVIDER: S-EPMC7375137 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Geometry and Topology of Estuary and Braided River Channel Networks Automatically Extracted From Topographic Data.

Hiatt Matthew M Sonke Willem W Addink Elisabeth A EA van Dijk Wout M WM van Kreveld Marc M Ophelders Tim T Verbeek Kevin K Vlaming Joyce J Speckmann Bettina B Kleinhans Maarten G MG

Journal of geophysical research. Earth surface 20200105 1

Automatic extraction of channel networks from topography in systems with multiple interconnected channels, like braided rivers and estuaries, remains a major challenge in hydrology and geomorphology. Representing channelized systems as networks provides a mathematical framework for analyzing transport and geomorphology. In this paper, we introduce a mathematically rigorous methodology and software for extracting channel network topology and geometry from digital elevation models (DEMs) and analy ...[more]

PMID: 32714724

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Dataset Information

Geometry and Topology of Estuary and Braided River Channel Networks Automatically Extracted From Topographic Data.

Publications

Geometry and Topology of Estuary and Braided River Channel Networks Automatically Extracted From Topographic Data.

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