Speaker
Description
Most phenological studies conducted in forests have focused on tree or woody species and early-season phenology, neglecting herbaceous species and autumn phenology. This leaves a gap in the mechanistic understanding of the entire life cycle of understory communities, despite their biodiversity, structural and functional role in forests. As autumn phenology is sensitive to summer droughts, this becomes particularly important in the context of climate change.
Therefore, we here studied six phenological stages spanning the entire life cycle of 261 populations of 30 herbaceous species from three temperate forest types in a dry and a wet year. We compared the phenology of communities between forest types and between the years. We ran mixed effects models to determine which environmental cue, soil moisture, light accumulation or growing degree days (GDD), was driving phenological responses.
The phenological composition of the herbaceous understory was organised along a flowering axis and a senescence axis in multivariate space, and depended more on species than forest type. The distribution of each phenological stage across all species, particularly leaf senescence and growing season length, differed between the two years, with a more condensed distribution in the drier year. Mean values, however, did not differ substantially. Furthermore, we found differences in species rankings in autumn phenology but not in first flowering day or peak flowering. Driving environmental cues depended on the phenological stage, with peak flowering advancing the most with GDD and initial growth advancing the most with light accumulation. We conclude that the timing of leaf senescence was strongly affected by summer droughts, implying consequences for plant performance and ecosystem productivity.
| Status Group | Doctoral Researcher |
|---|---|
| FOR TALKS: Poster Presentation Option | Yes, I’m willing to present as a poster. |