Abstract
The role of monsoon-induced wave action in driving mangrove loss in deltaic settings remains underexplored in comparison with the role of anthropogenic activities. Here, we reveal that the Ganges-Brahmaputra-Meghna Delta (GBMD), the world’s largest mangrove ecosystem within a monsoon-dominated region, exhibited an increased trend in total mangrove area at a rate of 133.3 ± 6.7 ha yr-1 from 1988 to 2022, despite a landward retreat of the mangrove shoreline at 5.98 ± 1.56 m yr-1. Monsoon-driven wave action is the primary driver of mangrove loss, with sea-level rise and tropical cyclones acting as critical amplifiers that exacerbate wave-driven erosion. In contrast, tidal currents promote sediment redistribution into channels, backshore areas, and around barrier islands and sandbanks, thereby fostering mangrove colonization and largely compensating for mangrove loss. Our findings highlight how southwest monsoon-induced waves drive mangrove loss, shedding light on the mechanisms underlying mangrove degradation in wave-dominated coastal areas.
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Data availability
The Landsat satellite imagery used in this study is available from the USGS Earth Explorer (https://earthexplorer.usgs.gov/) and the Google Earth Engine data catalog. The Global Mangrove Watch (GMW) dataset is available at https://www.globalmangrovewatch.org/. Wave energy data (ERA5) can be accessed via the Copernicus Climate Change Service (https://cds.climate.copernicus.eu/). Sea-level rise data are available from the NOAA Laboratory for Satellite Altimetry (https://www.star.nesdis.noaa.gov/socd/lsa/SeaLevelRise/). Typhoon track data are available from IBTrACS (https://www.ncei.noaa.gov/products/international-best-track-archive). The bathymetric data were obtained from the UK Hydrographic Office (https://www.gov.uk/government/organisations/uk-hydrographic-office) (restrictions apply to redistribution). Source data underlying the graphs and charts in the main text are provided as Supplementary Data 1.
Code availability
The mangrove classification and change detection were performed using Google Earth Engine (GEE) API. The shoreline change rates were calculated using the Digital Shoreline Analysis System (DSAS v5.0), which is publicly available at https://www.usgs.gov/centers/whcmsc/science/digital-shoreline-analysis-system-dsas. The calculation of wave energy flux followed standard formulations as described in the “Methods”.
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Acknowledgements
We would like to thank Professor Colin Woodroffe from the University of Wollongong for his valuable suggestions and insightful comments, which greatly contributed to the improvement of this manuscript. We also gratefully acknowledge Associate Professor Rongyong Huang from the School of Marine Sciences, Guangxi University, for his constructive and meaningful suggestions on the wave-related issues. Funding: This research was supported by the National Natural Science Key Foundation of China (NSFC) (41930537), the Shanghai International Science and Technology Cooperation Fund Project (23230713800; 24230740100), and 2024 International Cooperation Seed Funding Project for China’s Ocean Decade Actions (GHZZ3702840002024020000025).
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Conceptualization: Z.D. Methodology: Y.X., Z.D., and C.L. Formal analysis: Y.X. and Z.D. Data curation: Y.X Writing—original draft: Y.X., Z.D. Writing—review and editing: Z.D., C.L., X.M., J.C., and D.K. Visualization: Y.X., C.V., and B.N. Supervision: Z.D. Funding acquisition: Z.D.
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Xiong, Y., Dai, Z., Long, C. et al. Monsoon-driven waves induce a prevailing recession in mangrove forests across the Ganges-Brahmaputra-Meghna Delta. Commun Earth Environ (2026). https://doi.org/10.1038/s43247-026-03397-z
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DOI: https://doi.org/10.1038/s43247-026-03397-z
