RESUME

IMPROVEMENT OF THE ECONOMIC PERFORMANCE OF DIRECTLY CONTROLLED ENTERPRISES OF THE STATE ENTERPRISE “Lesy České republiky” (FORESTS OF THE CZECH REPUBLIC)
František Kaňok (pp. 444-446)

The state enterprise Lesy České republiky not only administers state-owned forests and operates in them with the aid of contractors, but also manages directly a part of the property through directly-controlled management units, these being namely the forest enterprises of Židlochovice, Boubín, Konopiště, Kladská, Dobříš and the very specialised seed plant of Týniště n. Orlicí. The directly-managed enterprises cover an area of 105 178 hectares of forest land, which sum amounts to 7% of the total area of forests managed by the state enterprise Lesy České republiky. 

The main intent of all the measures now being asserted, which the author of the article introduces, is to create conditions for the economic growth of the enterprises in future years and to initiate their further positive development by these pro-growth measures. Simultaneously, this orientation of approach to the management of forests for future value production, while supporting the non-wood producing functions, will require greater professionalism of the practical forester and thus, at the same time, of the professional forestry manager. The latter should be, in the complex concept of his own person, not only a good silviculturalist, but also an ecologist and simultaneously an economist, in order to be able to guarantee to the owner of the forest effective administration, effective management and augmentation of the future value of the forest and thus also of the entire forest property.

DEVELOPMENT STAGES OF PHYTOCENOSES
Eduard Průša (pp. 450-451)

Plant species are bound to certain environments by their occurrence. Plants have occupied a whole scale of various sites - still waters to arid rocks, igneous rock to quartzite, from thermophile oak stands to mountain pine. Various forests have their own plant communities, phytocenoses. Each has its own characteristic species, which testify to the forest environment. These plants also indicate their sites representatively, i.e. mainly the soil, trophic character and humidity. On the basis of this, 17 ecological plant groups were constituted. Czech forestry has for a long time concerned itself with the issue of spruce and pine monocultures, with their disastrous impact on continuous deterioration of the forest environment and the resulting decrease of production, safety and permanency. Due to the fact that the greatest changes of species composition have taken place in beech-oak (2.) and oak-beech forests (3.), the author analyses phytocenose changes in the region of Středočeská pahorkatina (Central Bohemian Hills). In conclusion, the author intimates that evaluation of the development changes under spruce and pine stands according to ecological groups, provides evidence of the progressive degradation of the forest environment and unsuitability of cultivating coniferous monocultures in the beech-oak (2.) and oak-beech forests (3.) of the altitudinal vegetation zones. For this reason it is essential that a supplementary mixture of broadleaf species is added (on prolific stands less, on the poor ones more) so that an improvement of the forest environment, both biological and economical, is achieved.

METHODOLOGY OF EVALUATION OF THE CROWN COVER OF CULTURES as a criterion of their security-as-plants on the basis of a computer analysis of images.
Jaroslav Simon, Pavel Mazal (pp. 458-459)

The moment of fulfilment of the content of the concept of a secured culture is a matter of cardinal importance from the aspect of development of a nascent stand. In the stage of a secure culture, the production phase of reforestation , or as the case may be, of growth by natural regeneration, terminates and the stands pass over to the growth grade of young-growth stands. Thus this concerns a transition period to the mentioned development stage, the growth phase following the advance growth, or as the case may be, of a partially grown culture. The basic criterion is the creation of a continuous crown layer. The crown-cover level can be evaluated figuratively on the basis of determination of the shaded area. Utilisation of the shaded area of young growth for evaluation of the security of cultures can also have the advantage that in the event of utilisation of special objective methods, it eliminates subjective evaluation, and thus the possibility of disputes. The method, which the authors offer, is the utilisation of computer analysis of images when evaluating aerial photographs.