HOLM OAK’S ROLE IN SHAPING COASTAL DUNE ECOSYSTEMS: A COMPREHENSIVE STUDY OF VEGETATION AND SPECIES COMPOSITION

This study investigates the ecological impact of Holm Oak (Quercus ilex) (HO) on dune ecosystems, focusing on its influence on vegetation cover, species richness, and species composition across different proximity levels (1m, 5m, and 20m from the tree) and dune types (Dune Plain and High Dune). Statistical analyses reveal that HO significantly reduces vegetation cover and species richness, with the most pronounced effects observed at 1m from the tree. Contrary to expectations, the presence of HO did not promote non-native species but
instead influenced native species dynamics. Additionally, HO’s impact on species composition was significant, altering the dominance of certain species, though the tree’s crown radius and height had minimal effect on vegetation cover and species richness. The study found no
significant variation in the HO’s impact based on proximity to the coast or dune type, although ecological pressures varied between the Dune Plain and High Dune. These findings highlight the need for targeted management of HO in dune environments to mitigate its invasive effects and preserve local biodiversity, with attention to both proximity effects and the ecological context of different dune types.