Abstract

The timing of autumn leaf senescence is crucial for ecosystem dynamics, influencing plant productivity and nutrient cycling. Despite its importance, the influence of species diversity on senescence and its implications for predicting phenological shifts in plant communities under climate change remain poorly understood. Here we address this knowledge gap by integrating ground-sourced data from Northern China with global remote sensing data to examine grassland ecosystems. Our analysis reveals that increased species diversity in grasslands leads to earlier autumn senescence, regardless of climatic and soil attributes. This effect is largely attributed to the effect of species diversity on resource allocation, enhancing belowground biomass at the expense of aboveground resources, thereby advancing senescence. Our findings highlight the role of biodiversity in modifying resource distribution and the growing season length, offering essential insights for understanding ecosystem responses to climate change.