Forest Phytocoenoses of Floodplain Terraces in Eastern Zangezur (Azerbaijan)

Abstract

This study examined the forest phytocoenoses of floodplain terraces in the Eastern Zangazur region, with particular attention to tree species composition, the structural features of the understory, projective vegetation cover, and the distribution of tree trunk diameters across different forest stands. The analysis showed that floodplain terraces located at comparable elevations exhibited no substantial differences in the taxonomic composition of their forest communities. A similar group of dominant and accompanying species was consistently recorded in all surveyed plots, indicating stable ecological conditions and relatively uniform habitat characteristics throughout the study area. The proportion of secondary species reserves varied notably among sites, ranging from 5% to 25%, depending on microrelief, soil moisture, and past disturbance history. Mensurational measurements demonstrated that the majority of trees possessed medium-sized trunk diameters, corresponding mainly to quality classes III–IV. These trees were typically middle-aged, falling within the 30–50-year age range, which suggests a moderately developed forest structure with ongoing natural renewal processes. Quercus iberica, one of the key species of the region, was present in all sample plots. Its average trunk diameter ranged between 18–20 cm, with heights generally reaching 6–8 m. The mean forest stock of this species was calculated at 71.7 m³/ha for individuals aged 40–110 years. Notably, the natural regeneration of Q. iberica was relatively high—approximately 72 young individuals per hectare—exceeding the regeneration rates of other associated tree species. Overall, structural disturbances observed within the studied forest stands were minimal. The data obtained serve as a valuable quantitative baseline for characterizing forest structure, species composition, and regeneration dynamics within the floodplain terraces of the Eastern Zangazur region, providing essential insights for long-term ecological monitoring and forest management planning