Comparison of the Biomass and Dendrometric Parameters of Norway Spruce with Its Different Representations in Young Stands at Lower Altitudes in the Czech Republic

In forestry, it is still common to plant the seedlings of and cultivate Norway spruce (Picea abies L. Karst) at lower altitudes; however, the climatic change that has been occurring increases evaporative demands in these areas. As a result, the spruce evidently suffers from drought, withers and loses its power to grow, thus, influencing stem thickness and tree-height growth, as well as biomass production. Therefore, the growth and biomass production of young (5-, 15- and 25-year-old) Norway spruce stands at these altitudes (i.e., from 200 to 500 m a.s.l.) was surveyed, as a case study, across the Training Forest Enterprise “Masaryk Forest” Křtiny. There, 48 stands with a varied representation of spruce (i.e., up to 30%, 31%–60%, 61%–90% and over 91%) were analyzed. In each stand, 12 trees were sampled across all social status classes (i.e., sub-dominant, co-dominant and dominant) in detail. Basic dendrometric parameters (such as the total tree height, height of the crown base and stem diameter at breast height) and the amount of the above-ground tree organ biomass (i.e., stem, branches and needles) were investigated. Based on the trends found in the biomass production here and climate change predictions, we recommend that Norway spruce be cultivated only in zones from an altitude of ca 400 m a.s.l., with an annual precipitation of 700 mm and an average annual temperature of 7 °C, and its percentage representation in the stand be no more than 30%.