Adaptation to water level variation: Responses of a floating-leaved macrophyte Nymphoides peltata to terrestrial habitats. Annales de Limnologie

Abstract – A straightforward experimental approach was carried out to study the adaptation responses of a typical floating-leaved aquatic plant Nymphoides peltata to changes in water availability. N. peltata grown in terrestrial habitat was approximately 88.77 % lower in total biomass, 62.75 % higher in root biomass alloca-tion, 80.9 % higher in root-shoot ratio, and 54.5 % longer in leaf longevity compared with N. peltata grown in aquatic habitats. Anatomical analyses suggest that aquatic-grown N. peltata exhibits a well-developed lacunal system in leaf, petiole, and coarse root. Moreover, aquatic-grown N. peltata had approximately a higher in lacunal system in leaf, petiole, and coarse root by 28.57%, 56.41 % and 82.35%, respectively, than those of terrestrial-grown N. peltata. These results indicated that N. peltata was well adapted to the terrestrial habitat because of its biomass allocation, morphological, and anatomical strategies that depended on the increase in root biomass allocation and leaf longevity, as well as the decrease in the lacunal system volume in leaf, petiole, and coarse root. This indicates that N. peltata can develop multiple morphological and anatomical strategies, an integrated approach to enhance survival in dynamic and unpredictable environments. Key words: Trade-off / adaptation / resource allocation / floating-leaved aquatic plan