The structure and development of spruce stands in the Sudeten system

This thesis regards the structure and development of spruce dominated forest stands in the most valuable parts of protected landscape areas of the Sudetes. The main goal of this dissertation thesis was to evaluate the vertical, horizontal and species diversity as well as modelling of growth processes of the mountain spruce stands on permanent research plots located in Orlicke hory, Krkonoše and Jizerské hory. Special attention was paid to the evaluation of regeneration processes after imission load recession. Thus, the forest natural regeneration process, dead wood evaluation and the health conditions of forest stands after the air-pollution calamity belong to the thesis partial goals. The study took place on permanent research plots of 50 x 50 m (0,25 ha) in size each where some of them have been observed since 1979 or 1980. Using the FieldMap technology, all stems with DBH > 4 cm were measured and localized. Furthermore, natural regeneration and dead wood was measured. The SIBYLA biodynamical growth simulation software was used to create the tree layer visualisation and development. The next property to monitor was the growth health according to tree foliage and its vitality via taking samples for radial growth evaluation. The results clearly show that studied forest stands are in different development stages. From the stage of recruitment to the stage of optimum all the way to the stage of degradation with strongly significant incidence of natural regeneration and dead wood. Their health state varies, a large part of them was strongly affected by imission-ecological calamity that signifies its state until present day. This event caused the death of a significant part of tree layer in the whole area belonging to the imission zone A, alternatively immision zone B. The development of growth characteristics reflects this, they take on different stand structural characteristics. The number of living trees vary from 268 to 1832 per ha, the stock of living trees varies from 11 to 195 m3.ha-1