Phenological observations and potential future shifts in the onset of the selected phenophases of representative spring plant species in Slovenia (<i>Corylus avellana</i>, <i>Taraxacum officinale</i>, and <i>Syringa vulgaris</i>)

<p dir="ltr">To assess the changes in the spring phenology in the future with particular emphasison the elevation dependence of phenophase onset, a climate-driven phenological model was developed based on the spring indices methodology. Our study investigates both current and projected changes in the timing of flowering onset for common hazel (<i>Corylus avellana</i>), dandelion (<i>Taraxacum officinale</i>), and common lilac (<i>Syringa vulgaris</i>). We compiled comprehensive climate data and phenological records from 46 phenological stations of the National Phenological Network of the Slovenian Environment Agency for the period 1971–2020.We used climate projection data for the 21st century under two climate scenarios to evaluate potential future shifts in the onset of the selected phenophases. Specifically, we examined whether the agreement between model predictions and observed records varies with elevation during the reference period (1981–2010) and whether this relationship changes across three future climate periods till 2100.</p>