The present paper shows the results of research on the comparative areas that were laid out in compartments 89, 108, 109 in the Olomucany forest district, School Training Forest Farm of the Faculty of Forestry, University of Agriculture, Brno. Different forest cultural treatments and forest stand composition are studied on these areas and basic climatic data are collected that influence the growth and production of forest tree species. This research is extended within the program Man and the Biosphere by evaluating the human activity which exerts a significant influence on the overall formation of environment and natural conditions. The objective of research on the mentioned areas is a comparison of crown thinnings by positive selection with low thinning of grade B and with an untended area, i.e. the control area. In five-year cycles from 1960 to 1980 the growth development of forest stands was recorded five times, and for ten years the basic microlimatic values have been measured, including the increments of forest tree species. Cultural treatments in these stands must be aimed at the best stand composition, conifers must be promoted and it is necessary to maintain the height differentiation of forest stands, setting free the light- demanding species and conserving the soil cover to retain the moisture as a reservoir of drinking water. This means to apply the combined methods of tending these stands and to find such an approach to each tree species to meet the requirements for its prosperous growth as best as possible.
