Ecosystem Phenology: Integrating Traits and Processes Beyond Observable Events

Phenology-the study of seasonal biological events shaped by climate variability-has long offered critical insights into the impact of climate change on ecosystems. Traditionally, phenological research has focused on discrete and observable events such as budburst, leaf-out, flowering, and migration. Yet ecosystems are not driven by isolated events alone, but by continuous shifts in functional traits and biogeochemical processes. The event-based phenology framework often overlooks this dynamic variability in traits and processes. To completely understand the temporal change in ecosystem functioning, we propose an expanded concept-ecosystem phenology-which integrates functional traits and biochemical processes beyond visible events. By capturing the full temporal spectrum of ecosystem dynamics, the ecosystem phenology framework provides a comprehensive understanding of ecosystem responses to climate change, with significant implications for forecasting ecosystem function and informing climate policy.