Home – Home – Jornals – Siberian Journal of Forest Science 2019 number 3

The results of comparative analysis of adaptive features of bark and secondary xylem of the spirea of Bower Spiraea beauverdiana Schneid (Rosaceae Juss.) are presented in the extreme conditions of the Arctic and volcanic activity in the Kuril Islands. Structural analysis of the bark and wood parameters in ontogenesis under the conditions of post-volcanic activity is carried out. The identified features are of adaptive character and are aimed at optimizing the water supply system. It has been established that the combination of environmental factors in conditions of gas-hydrothermal outputs of the Golovnin volcano caldera on the Kunashir Island causes disruption in the activity of phellogen and cambia. Unstable operation of these meristems leads to the formation of tissues of abnormal structure, forming separate loci in the stem, as well as tissues with deviations from the normal structure. In terms of their structural and functional characteristics, the anomalies formed in the secondary phloem and xylem are similar to the anomalies caused by stem pitting syndrome. The commonality and specificity of structural reaction of the secondary xylem under these conditions is revealed. In these extreme conditions, spirea of Bower wood retains its juvenile features throughout the entire ontogenesis, with solitary and cluster vessels located within one year growth ring. More specialized vessels, cluster vessels are more narrow and larger rays are present, with the former being homogeneous (ray cells upright) and the latter being mixed heterogeneous and heterogeneous (rays with procumbent, square and upright cells).