J Plant Ecol ›› 2023, Vol. 16 ›› Issue (6): rtad026.DOI: 10.1093/jpe/rtad026

• Research Article •    

Inter- and intraspecific adaptations of pteridophyte leaf traits in limestone and non-limestone forests of monsoon tropical regions of southwest China

Kittisack Phoutthavong1,2, Masatoshi Katabuchi1,*, Akihiro Nakamura1,3, Xiao Cheng4, Min Cao1,3   

  1. 1CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla 666303, China;
    2University of Chinese Academy of Sciences, Beijing 100049, China;
    3Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Menglun, Mengla 666303, China;
    4Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China


Abstract: Plant species often show different taxonomic and functional characteristics between limestone forests (LFs) and non-limestone forests (NLFs) in tropical regions. Pteridophyte species are one of the major components in tropical rainforests; however, the morphological and physiological characteristics of pteridophytes occurring in LFs are poorly understood. We evaluated the differences in seven leaf functional traits between pteridophyte species in LFs and NLFs in southwest China. We measured leaf water content, morphological traits including leaf size, leaf thickness, stomatal length and stomatal density (SD), and physiological traits including stomatal conductance and photosynthetic rate from a total of 25 species. We found that pteridophytes had thicker and smaller leaves with lower SD and stomatal conductance in LFs compared with NLFs, probably reflecting their adaptations in water use strategies. These differences, however, became non-significant when phylogenetic relationships were taken into account, suggesting that phylogenetic conservatism shapes trait differences and ultimately species composition in LFs and NLFs. Some species that were commonly found in both LFs and NLFs exhibited intraspecific variation between forest types, with lower SD in LFs. Our findings suggest that only a handful of pteridophyte species can adapt to their water use strategies in both LFs and NLFs, and thus adaptative radiation is unlikely to occur.

Key words: drought, fern, limestone forest, pteridophytes, leaf functional traits, Xishuangbanna


关键词: 干旱, 蕨类, 石灰山森林, 蕨类植物, 叶片功能性状, 西双版纳