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Parametric transitions between bare and vegetated states in water-driven patterns.

ABSTRACT: Conditions for vegetation spreading and pattern formation are mathematically framed through an analysis encompassing three fundamental processes: flow stochasticity, vegetation dynamics, and sediment transport. Flow unsteadiness is included through Poisson stochastic processes whereby vegetation dynamics appears as a secondary instability, which is addressed by Floquet theory. Results show that the model captures the physical conditions heralding the transition between bare and vegetated fluvial states where the nonlinear formation and growth of finite alternate bars are accounted for by Center Manifold Projection. This paves the way to understand changes in biogeomorphological styles induced by man in the Anthropocene and of natural origin since the Paleozoic (Devonian plant hypothesis).

SUBMITTER: Bertagni MB

PROVIDER: S-EPMC6094146 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Parametric transitions between bare and vegetated states in water-driven patterns.

Bertagni Matteo Bernard MB Perona Paolo P Camporeale Carlo C

Proceedings of the National Academy of Sciences of the United States of America 20180723 32

Conditions for vegetation spreading and pattern formation are mathematically framed through an analysis encompassing three fundamental processes: flow stochasticity, vegetation dynamics, and sediment transport. Flow unsteadiness is included through Poisson stochastic processes whereby vegetation dynamics appears as a secondary instability, which is addressed by Floquet theory. Results show that the model captures the physical conditions heralding the transition between bare and vegetated fluvial ...[more]

PMID: 30038019

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