Prediction of Potentially Suitable Areas of Hazelnut (Corylus avellana L.) in Romania Based on Bioclimatic Variables
DOI:
https://doi.org/10.61326/silvaworld.v5i2.517Keywords:
Corylus, Hazelnut, Range dynamics, Shared socioeconomic pathways, Species distribution modelsAbstract
The hazelnut (Corylus avellana L.) is widespread throughout Europe, except in the northeastern parts. Due to its exceptional nutritional profile and associated health benefits, it’s recognised as a premier nut crop, ranking fifth among nut crops, based on total harvested area. The objectives of this study were: to identify the bioclimatic variables that influence the distribution of hazelnut in Europe, to predict its current and future habitat suitability in Romania and to evaluate the range dynamics. Annual Mean Temperature (BIO1), Precipitation of Warmest Quarter (BIO18), Temperature and Precipitation Seasonalities (BIO4 and BIO15, respectively) were the bioclimatic variables with the highest relative importance. The present climate conditions indicate that around 11% of the country is suitable for hazelnut, i.e. above the 0.8423 threshold. Based on the levels of suitability, more than a quarter of the country presents excellent habitat suitability (above 0.80) and more than half good habitat suitability (above 0.60). Under SSP5-8.5, for the 2081-2100 period, the suitable area for hazelnut (above the 0.8423 threshold) is predicted to be around 1600 km2 (around 700 km2 of expansion area and around 900 km2 stable area). Based on the levels of suitability, for the same SSP and period, the area with climate conditions corresponding to an excellent habitat suitability (above 0.80) is predicted to be about 15900 km2. Modelling climate-driven shifts in species distribution is crucial for equipping forest managers and policymakers with dependable adaptation frameworks. To improve predictive accuracy for hazelnut, future studies should incorporate additional critical environmental variables.
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