Woody Species Dynamics in the Priority Habitat 91E0* in Nestos, Greece

Tree species composition, stand structure, and growth dynamics were evaluated within the priority habitat 91E0* (alluvial forests with Alnus glutinosa (L.) Gaertn., and Fraxinus excelsior L.) in the Nestos region of northeastern Greece. This study aimed to understand the ecological dynamics of this unique habitat and to properly plan restoration actions. Measurements were conducted in May and July 2023 across 14 plots distributed randomly along both banks of the Nestos River (east and west). A total of 667 trees with a DBH ≥ 2.5 cm were recorded, representing 13 species and 10 families. Tree densities ranged from 14 to 541 stems ha−1, and the average basal area was 8.77 m2 ha−1. Both density and basal area significantly differed between the two riverbanks. Our results indicate that Alnus glutinosa dominates in the alluvial forest, forming more resilient communities with Populus alba L., Populus nigra L., and Salix alba L. However, Fraxinus angustifolia Vahl was not as prevalent as expected. These findings highlight the need for conservation actions and draw attention to the threats facing the alluvial forest.