Intra- and Inter-Specific Variation on Flowering and Fruiting Phenology in Gutianshan Subtropical Evergreen Broad-Leaved Forest, Zhejiang Province

Abstract

Phenology, the timing of recurrent life-history events, including bud bust, leaf out, flowering, fruiting, and leaf senescence, are related to environmental conditions and species interactions. As one of the most important plant functional traits, the qualitative correlation between inter- and intra-specific phenology variation and community structure has not been investigated at the community level. We monitored both flowering and fruiting phenology for 106 species during 2012 to 2015 in a Gutianshan 24ha permanent plot in a subtropical evergreen broad-leaved forest in Zhejiang province. We used standard deviation to evaluate inter-and intra-specific phenology variation. Results showed that precipitation was the major climatic factor influencing flowering phenology; most species flowered in May at the community level; fruiting phenology reached its peaks on October. Interspecific variation of flowering phenology was larger than that of fruiting phenology. The standard deviation of the interspecific variation of flowering phenology was 52, and of interspecific variation of fruiting phenology was 41. However, intraspecific variation on flowering phenology was smaller than fruiting. At the community level, intraspecific variation on flowering and fruiting phenology was smaller than intraspecific variations. Intraspecific variation on phenology at the community level was not significantly correlated with species abundance. Intraspecific variation of flowering phenology did not have a significant relationship with flowering date. However, intraspecific variation of fruiting phenology had a significant negative relationship with fruiting date. Intraspecific variation of fruiting phenology decreased as fruiting date increased. To our knowledge, this is the first study to explore the relationship between intraspecific phenology variation and phenology date and the first to evaluate the relationship between intraspecific phenology variation and species richness. Coupling these quantitative phenological data with community structure (abundance)will extend phenological analyses to understand how changes in phenology, andresulting changes in species interactions, affect fitness, an importantconcept for understanding the lasting impacts of phenological change, traits variation, and species diversification in the context of climate change.