Coastal zones have experienced significant anthropogenic alteration, facilitating the spread of invasive alien species, such as Rugulopteryx okamurae in the Strait of Gibraltar, which colonises rocky bottoms and creates massive accumulations of biomass along coastlines. Marine macrophytes, macroalgae and seagrasses, can form beachcasts as part of their natural life cycle. However, the increased frequency and abundance of R. okamurae beachcasts has had ecological and economic impacts since 2015 in southern Spain, Portugal and Morocco, yet no beachcast monitoring programs have been developed. This study focuses on the radiometric characterisation of Zostera noltii seagrass and R. okamurae macroalgae beachcasts to assess their spectral differentiation across degradation stages linked to water content, pigment photooxidation and photoprotection mechanisms. Sentinel-2 and PlanetScope SuperDove multispectral satellite imagery was used to evaluate their capacity to track beachcast degradation stages, highlighting the usefulness of the three red-edge, narrow Near-Infrared (NIR) and SWIR bands from Sentinel-2. Results showed notable differences in the degradation processes of the two species, with R. okamurae beachcasts retaining more water, yet exhibiting faster pigment degradation compared to Z. noltii. These insights are crucial for large-scale monitoring of R. okamurae beachcasts using Earth Observation, offering a framework for biomass quantification to improve the operational management of this marine invasive species.
- Beachcast degradation stages of Rugulopteryx okamurae and Zostera noltii: towards a scalable remote-sensing monitoring platform
- Mar Roca-MoraBede Ffinian Rowe Davies - Centre National de la Recherche ScientifiquePierre Gernez - Institut Des Substances et Organismes de la MerMaria Laura Zoffoli - National Research CouncilLaurent Barillé - Institut Des Substances et Organismes de la Mer
- Remote Sensing Applications: Society and Environment, Vol.43
- 99259556509311
- MARBEC - MARine Biodiversity, Exploitation & Conservation
- English
- Journal article
- hal-05684976