Ignacio J. DIAZ-MAROTO, University of Santiago de Compostela, Spain
Pablo VILA-LAMEIRO, University of Santiago de Compostela, Spain
The deciduous oak forests are generally the potential vegetation of the Iberian Northwest. Among them are the sessile oak forests (Quercus petraea (Matt.) Liebl.), which present a valuable diversity of vascular plants. Our goal is to analyse the floristic biodiversity of these ecosystems, most of which located in areas of the Natura 2000 Network. The study area includes lands of Galicia, Asturias, and León, where a total of 50 floristic inventories were carried out, assigning to each species an abundance-dominance index. For this, homogeneous vegetation areas with a minimum surface of 100 m2 were selected. Later, we used the dichotomous classification method of stands from the TWINSPAN program. The results show a higher number of phanerophytes and camephytes compared to hemicryptophytes, therophytes and geophytes, identifying 30 families and 15-20 species per inventory. Regarding the chorological spectrum, the Atlantic elements stand out, 32%, the presence of Mediterranean elements being scarce, 7%. Eleven final groups have been obtained in the dichotomous classification. As a more relevant conclusion, note the need to carry out a greater number of inventories, avoiding those areas where the understory is altered. A greater homogeneity of environmental conditions is also necessary, restricting the study to a different scale than the species, e.g., phytosociological association, or even, at mountain system or river basin level.
Mots clés : Deciduous oak trees|biodiversity|floristic inventory|TWINSPAN|phytosociological association
A103693ID