Linking trophic cascades to changes in desert dune geomorphology using high-resolution drone data

Area of Science:

• Geomorphology
• Ecology
• Remote Sensing

Background:

• Vegetation cover is crucial for dune geomorphology.
• In arid Australia, dingo (Canis dingo) removal has led to increased woody shrub cover through trophic cascades.

Purpose of the Study:

• To investigate if increased shrub density, linked to dingo eradication, alters dune physical characteristics.
• To understand the geomorphological impacts of trophic cascades in arid dune systems.

Main Methods:

• Utilized drone-based remote sensing to measure shrub density.
• Constructed 3D models of dune morphology.
• Employed generalized additive models to analyze dune characteristics in relation to shrub density.

Main Results:

• Dunes differed significantly in physical characteristics on either side of the dingo-proof fence.
• Increased shrub density correlated with higher, differently shaped, and more variable dune height profiles.
• High shrub density promotes dune stability, while low density increases erosion and sediment transport.

Conclusions:

• Anthropogenically induced trophic cascades can indirectly cause large-scale landscape geomorphological changes.
• Increased vegetation cover can shift dune systems towards an alternate stable state, reducing climate-driven morphodynamic variability.
• The study highlights the interconnectedness of predator-prey dynamics and landscape evolution.