Staquet Adrien auteur aut IRD Proisy Christophe auteur aut IRD Gardel A. auteur aut IRD Augusseau P. E. auteur aut IRD Maury T. auteur aut IRD Attali A. auteur aut IRD Brunier G. auteur aut IRD Facundes F. auteur aut IRD Frati G. auteur aut IRD Granjon Laurent auteur aut IRD Leroy Céline auteur aut IRD Mury Antoine auteur aut IRD Santos V. F. auteur aut IRD Anthony E. J. auteur aut IRD text journalArticle eng text/pdf born digital access The role of substrate elevation in the establishment of mangroves has been highlighted in the literature. However, the link between elevation and mangrove growth over large areas remains poorly known. To address this issue, we conducted an experiment in French Guiana, where extensive mud banks provide large areas of accreting mudflats over which occurs rapid mangrove expansion. About 15 ha of a mudflat were topographically surveyed monthly to bimonthly over 19 months using Unmanned Aerial System (UAS)-based high-resolution photogrammetry, and environmental variables (vegetation, water depth, temperature, salinity) continuously measured. During the experiment, the mudflat elevation increased by 0.9 m, from 2.4 to 3.5 m above Lowest Astronomical Tide level, in the wake of mud-bank sedimentation. About 5.5 ha were colonised by Laguncularia racemosa and Avicennia germinans mangroves in less than 4 months. Once the elevation reached 2.8 m, close to Mean High Water Neaps, abundant seedlings rapidly established and spread. Therefore, mapping elevation using UAS-photogrammetry reveals how coastal accretion can trigger mangrove establishment. We discuss the advantages of this cost-effective tool in confidently identifying critical elevation levels for natural mangrove establishment and for viable mangrove restorations, many of which fail due to poor knowledge of substrate elevation. We show the limitations of photogrammetric surveys once the mangrove cover develops. Monitoring the link between mangrove establishment and elevation can provide essential insight in the anticipation of coastal change and in the successful implementation of mangrove-based ecological restoration. specialized Mangroves Muddy sedimentation UAS photogrammetry Mudflat elevation Ecological restoration Nature-based solution South America GUYANE FRANCAISE CAYENNE 021 126 082 032 337 109903 [16 p.] 2026 0272-7714 https://www.documentation.ird.fr/hor/fdi:010097067 10.1016/j.ecss.2026.109903 0272-7714 [F B010097067] https://www.documentation.ird.fr/hor/fdi:010097067 https://www.documentation.ird.fr/intranet/publi/2026-06/010097067.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2026-06-10 2026-06-12 fdi:010097067 fre