The premise of the study Though phenological studies in montane forests are important, particularly in tropical Asia where primitive angiosperms are found, the phenology in these forests is still poorly understood. To characterize the phenological patterns and reveal the relationships between meteorological factors and phenology, we observed the leafing, flowering, and fruiting phenology in the tropical montane forests of Vietnam. Methods We observed the leafing, flowering, and fruiting phenology of 91 species every three months in five plots (elev. 1460–1920 m) in Bidoup-Nui Ba National Park, Vietnam, and analyzed how the number of species that were leafing, flowering, or fruiting varied in relation to precipitation, temperature, or daylength. Key results The leafing phenology showed a peak at the beginning of the wet season (April) and was significantly influenced by all of day length, precipitation, and temperature. The flowering phenology did not show any distinct peaks and was influenced by day length and precipitation. The fruiting phenology showed a low peak from the wet season (July) to the beginning of the dry season (December) and was not significantly influenced by any of the meteorological factors. Main conclusion The community-wide phenological patterns of leafing, flowering, and fruiting in the tropical montane forest of Bidoup-Nui Ba are unique among the tropical forests of East and Southeast Asia. In particular, our observation suggests that masting in tropical montane forests may be an ancestral state of both general flowering in tropical rainforests and masting found in temperate forests in East and Southeast Asia.

Understanding the structure and connectivity of coral populations is fundamental for developing marine conservation policies, especially in patchy environments such as archipelagos. The Nansei Islands, extending more than 1,000 km in southwestern Japan, are characterized by high levels of biodiversity and endemism, supported by coral reefs, although precise, detailed genetic attributes of corals are still largely unknown. In this study, we conducted population genomic analyses based on genome-wide, single-nucleotide polymorphisms (SNPs) of Acropora digitifera, a common species in the Nansei Islands, for which a complete genome is available. With ~24x sequencing coverage of entire genomes of 303 colonies collected at 21 locations, we identified more than four million genome-wide SNPs. While population structure analyses suggested weak genetic differentiation among sampled locations, the most southwestern location (the west end of the Yaeyama Islands) was genetically similar to the northernmost location (the Tanegashima Islands), separated by >1,000 km. Although examination of a migration network found a general tendency of northward migration along the Kuroshio Current, a substantial amount of southward migration was also detected, indicating important contributions of minor ocean currents to coral larval dispersal. Moreover, heterogeneity in the transition of effective population sizes among locations suggests different histories for individual subpopulations. The unexpected complexity of both past and present population dynamics in the Nansei Islands implies that heterogeneity of ocean currents and local environments, past and present, have influenced the population structure of this species, highlighting the importance of local scale assessments for effective coral restoration and management.