An analysis of exposure effect on treeline ecotone, Krkonoše Mts.

The thesis deals with the influence of thermal conditions on the growth of the trees along the slopes with differing exposure to solar radiation in the alpine treeline ecotone in the Eastern Giant Mountains. Methodological approach was based on the measuring of the tree top and root zone temperatures, measurement of the dendrometric parameters (tree height, length increment) and radial increment of the Norway spruce (Picea abies). The results show only weak relation between significant temperature characteristics and exposure effect in the alpine treeline ecotone, which correspond to the growth rates of the sampled trees. Slightly higher temperatures were found on the south-facing slopes during the growing seasons in case of the closed canopy forest. Soil and air temperatures in tree groups were a bit higher on the north-facing slopes. In closed-canopy forest there was larger radial increment on south-facing slopes of Lu_ní hora, on the slopes of Malý Šišák there were similar growth trend on both slope exposures. In tree groups there were found larger increments on north-facing slope of Lu_ní hora, on the sampled sites of Malý Šišák there were found larger increment on south-facing slope during the 20th century, then in last decade larger increment was recorded on northfacing slope. Based on standard..