Vegetation against dune mobility

TL;DR

This paper develops a mathematical model describing how vegetation stabilizes sand dunes and identifies a critical index that determines whether dunes are stabilized or not.

Contribution

It introduces a novel set of equations modeling the competition between sand transport and vegetation growth, enabling quantitative analysis of dune stabilization.

Findings

Identification of a critical fixation index $ heta_c$ for dune stabilization

Scaling laws describing stabilized dunes below the critical index

Quantitative framework for dune-vegetation interaction

Abstract

Vegetation is the most common and most reliable stabilizer of loose soil or sand. This ancient technique is for the first time cast into a set of equations of motion describing the competition between aeolian sand transport and vegetation growth. Our set of equations is then applied to study quantitatively the transition between barchans and parabolic dunes driven by the dimensionless fixation index $\theta$ which is the ratio between dune characteristic erosion rate and vegetation growth velocity. We find a fixation index $\theta_c$ below which the dunes are stabilized characterized by scaling laws.