The structure S of a system is ordered pair S = {M; RM} of the set M of elements of the system and set RM of relationships between elements of the system. For ecosystems and communities, it is possible to recognize species structure, spatial structure, functional structure and temporal structure, for example. Temporal structure corresponds to the concepts of ecosystem dynamics and succession. Climate is one of the key external factors of succession. An analysis of the development of the regional precipitation and the regional temperatures since 1961 was presented. A switch point in the development of precipitation was observed around 1973. A similar point in the development of air temperature was located near to the year 1996. This is consistent with the division of the period 1983-2012 between years 1994/1995 using measurement at the weather station Churáòov. The last period is characterized not only with an increase in average temperatures, but also by increasing the variability of total precipitation.
Soil is an important component of the terrestrial ecosystems. The soil has a complex three-dimensional structure. As an example, the difference between seventh (spruce with beech) and eighth (spruce) forest altitudinal zone (FAZ) was described using surface soil horizons using probes randomly spaced with distances of several meters. Selected features have specific correlations - they form the specific structures, which differ in 7th and 8th FAZ. Differences were also discovered in the species structure of oribatid communities.
The incidence of spruce bark beetle (Ips typographus) is one of the factors that significantly affect the status of mountain spruce forests. This beetle can be considered as a key species for the dynamics of these forests and their regeneration. The bark beetle is spread in the stand selectively depending on the status of individual trees. Infestations of the stands are also very variable regarding to the character of the stand (density, origin, prevailing tree form). For the possibility of the bark beetle gradation, fluctuations in the weather are important, especially the incidence of dry and warm periods.
Forest management after the tree dieback has a major influence on the development of the entire ecosystem. For instance, the analysis of state of the epigeic-beetle communities has been shown that active silviculture management with thinning changes the state of the ecosystem much greater than passive non-intervention management. Nature conservation prefers therefore passive management in the climax mountain Norway spruce forests.
For the forest ecosystem is significant spatial arrangement of trees in the canopy, which often determines the spatial structure of small-scale units (plant microcoenoses) of the herb layer. It is particularly evident in some forest communities such as the climax spruce forests near the upper tree limit or successional stages on former treeless plots where trees (Acer pseudoplatanus or Picea abies) enters individually within scattered small plots (gaps).
This paper was prepared in connection with the seminar "Forester of the 21st century", which took place in Stachy on February 26th, 2015.
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