Abstract
Pollen and spore morphology provides essential taxonomic reference data for floristic and environmental studies in tropical regions, where modern comparative datasets remain limited. This study documents the morphological characteristics of pollen and spores recovered from a shallow soil profile in a degraded mixed deciduous forest within Sri Nan National Park, northern Thailand. Using a non-acetolysis extraction protocol and systematic sub-sampling of a 30-cm profile, pollen and spores representing 37 plant families were identified, including lycophytes, bryophytes, monilophytes, gymnosperms, and angiosperms. Spore-producing taxa, particularly monilophytes, dominate the assemblage, while angiosperm pollen includes both arboreal and non-arboreal elements. More than 100 morphotypes are described based on aperture type, exine ornamentation, size, and symmetry, supported by high-resolution photomicrographs and standardized morphotype descriptions. The resulting dataset expands the regional palynological reference framework for northern Thailand and tropical Southeast Asia and supports consistent taxonomic identification in palynological, floristic, and comparative paleoecological studies, particularly in human-impacted forest–agriculture mosaics.
Data availability
Data supporting the findings of this study are provided in the Supplementary Information, including the morphotype dataset (Supplementary). Additional materials are available from the corresponding author upon reasonable request.
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Acknowledgements
This research was financially supported by the National Research Council of Thailand (NRCT) under the Research and Innovation Fund for the Fiscal Year 2024, through the Young Researcher Development Grant (grant number N42A670907). Sincere appreciation is also extended to the park and the Department of National Parks, Wildlife and Plant Conservation for facilitating access to the study area and providing valuable assistance during field data collection. Special thanks are given to the Laboratory of the Faculty of Environment and Resource Studies, Mahidol University, for providing laboratory facilities, equipment, and academic collaboration in the palynological analysis, as well as to the academic staff for their invaluable guidance and technical advice. We also gratefully acknowledge the editor and anonymous reviewers for their constructive comments, which significantly improved the clarity and scientific rigor of the manuscript.
Funding
This project is funded by National Research Council of Thailand (NRCT) (grant number N42A670907). Open Access funding enabled and organized by Mahidol University.
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T.S. conceived and designed the study, conducted field sampling, laboratory processing, microscopy, and morphotype documentation, and drafted the original manuscript. T.P. and Y.T. contributed to data interpretation and critical revision of the manuscript. S.V. contributed to interpretation of the results and manuscript revision. All authors reviewed and approved the final manuscript.
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Sattraburut, T., Vongvassana, S., Phutthai, T. et al. Morphological diversity of pollen and spores in a human-impacted highland forest–agriculture mosaic in northern Thailand.
Sci Rep (2026). https://doi.org/10.1038/s41598-026-37899-9
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DOI: https://doi.org/10.1038/s41598-026-37899-9
Keywords
- Palynomorphs
- Palynological reference dataset
- Non-acetolysis preparation
- Tropical forest–agriculture mosaic
- Southeast Asia
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