Seminar: Andrea Silva Cala

Understanding plant phenology patterns is important because they influence processes from specific dynamics, like species interactions, to ecosystem functions, for instance, carbon uptake. Due to the lack of long-term data that covers the species’ distribution, the space-for-time substitution approach is commonly used. However, this method relies on the rarely tested space-time equivalence assumption. In this study, we used long-term ground-based observation of the onset of flowering to assess the space-for-time equivalence assumption. Specifically, we compared the flowering phenology responses to temperature along both temporal and spatial gradients. Furthermore, we evaluated the influence of changing annual mean temperatures on this relationship, analyzing the responses between 1950-1985 and 1986-2022. The results show that the use of space-for-time substitution correctly predicts the phenological response direction to temperature, being 67% similar between both gradients. We found that the responses were more consistent in warmer decades (1986-2022), showing a reduction of the variation, especially in the temporal gradient. This study may serve as a reference for future studies on plant phenology using space-for-time substitution.