Marine plastics as geomorphic agents in coastal dune systems: UAV framework and nature-based solutions

Coastal dunes worldwide trap marine plastics within psammophilous vegetation. Such processes may impact dune formation by altering sediment dynamics and affecting plant health. This study aims to assess whether plastics act as active geomorphic agents and explores how strategic vegetation management could transform this challenge into Nature-Based Solutions (NBS) for coastal regions at risk from plastic pollution.We aim to develop a comprehensive UAV-based framework to evaluate interactions among plastic, vegetation, and geomorphology in dune systems. High-resolution surveys produce orthomosaics and DSMs, enabling us to map plastic distribution alongside traditional dune features such as scarp development, sediment retention volume, surface roughness, and gradients of vegetation health.The analysis is guided by three research perspectives:Plastic entrapment dynamics by dune-building speciesVegetation response to debris accumulationGeomorphic feedbacks influencing dune profile evolutionBy establishing quantitative links between plastic accumulation and measurable geomorphic change, this study aims to identify critical thresholds where pollution may transform protective dunes into erosion-prone features. Marine plastics are regarded as a quantifiable factor influencing dune evolution, providing insights for vegetation-based strategies to maintain coastal stability.Keywords: marine plastics, coastal geomorphology, UAV remote sensing, Nature-Based Solutions, dune evolution