Biological and chemical (fertilising, liming) amelioration are among the principal tools used to restore degraded sites. These techniques were also used on the Ore Mts. plateau on plots prepared by bulldozing. We evaluated the impact of these amelioration techniques by measuring tree species primary production and humus form restoration. Begun in 1983Begun in -1985, this project studied growth reaction of forest stands by measuring height and diameter increment, for the following species (blue spruce Picea pungens Engelm., European larch Larix decidua Mill., lodgepole pine Pinus contorta Dougl., Eastern white pine Pinus strobus L., alder Alnus incana Moench., European beech Fagus sylvatica L.) during the period 1994-2000. The growth potential by species decreases in the following order: larch, alder, lodgepole pine, white pine, blue spruce. Beech was almost exterminated by red deer browsing and the harsh climate; pines suffered heavily from browsing and bark stripping. Holorganic horizons were measured and basic soil chemical and mechanical characteristics were determined -pH, soil adsorption complex characteristics (using Kappen's methodology), content of the humus and total nitrogen, exchangeable acidity and plant available macronutrients, granulometric composition of mineral soil horizons. Our results confirmed the relatively long-lasting effects of soil amendments, as well as the amelioration effects of alder, and the relatively inhibiting effects of larch and blue spruce.

ABSTRACT:Norway spruce (Picea abies [L.] Karst.) provenances from Central Europe (Hercynian-Sudetes area) were evaluated in a long-term experimental project (Germany-Czech Republic) 36 years after the outplanting. The growth characteristics, mortality and qualitative morphological characteristics of 64 spruce provenances were evaluated on the experimental plot Ledeč-Zaháj, in the Czech-Moravian Highland region of the Czech Republic, in typical conditions for Norway spruce cultivation. Results show 15-20% differences in height and radial growth between provenances and insignificant differences in qualitative characteristics e.g. stem shape, branch density and shape and also health state. Environmental variables that significantly influenced production characteristics include longitude, latitude and altitude of the original locations of the provenances, while average annual temperature and average annual precipitation were not significant. Given conditions of the experimental plot, optimal production occurred with those provenances originally from 49-51 N latitude and 13-20 E longitude.

ABSTRACT:The aim of this study was the evaluation of the spruce natural regeneration growth and development in Modrava and Plechý areas, which represent the first and late bark beetle attack areas. Study was done on 13 permanent research plots, partly with vital tree layer and canopy cover and partly characteristic by open or none canopy, due to bark beetle attack. Actually amount of this regeneration is sufficient (average over 12,000 pcs/ha in the living stands and almost half of this amount in the declined stands) on the both types of plots. Faster growth is usually on the declined plots, with saplings larger amount and height increments, in the higher height classes. Particular interest was aimed to the microhabitat conditions, especially herbal cover influence. There were statistically important differences in the amounts and height growth of the first height class on the different microhabitats. As the most sufficient for the seedlings occurrence appeared to be the dead wood and the least suitable were fern and grasses. For the height growth the least suitable was vital tree foot with litter cover. The results indicate, that declined stands, without vital mature trees and without seed source, will likely develop into more or less even-aged forest.

Restoration of forest soil character after the change of agricultural land use has not been studied yet despite the large areas reforested since the late 40ies of the last century. This process takes place throughout Europe to an increasing extent at present. The reformation of forest soils was studied in the area of Český Rudolec town: Natural Forest Area 16 – Czech-Moravian Uplands, altitude 600–630 m a.s.l., bedrock is built of granites and gneisses, soil type is Cambisol, forest site type 5K1. The process of restoration of a new humus form was analysed in plantations of American red oak (Quercus rubra), Swedish birch (Betula pendula), European larch (Larix europea) and Norway spruce (Picea abies), the site was homogeneous. The particular tree species accumulated 12.81, 13.81, 46.57 and 44.76 t/ha of surface organic matter during the last 30–40 years, these values are typical of forest sites at lower and middle altitudes and corresponding tree species composition. The effect of broadleaved species and conifers was markedly different, in the first case pH in KCl ranged 3.8–3.9 (mineral soil) and 3.5–5.2 (holorganic horizons), being 3.5–3.8 (mineral soil) and 3.1–5.1 (holorganic layers) for the conifers. Visible effects of the particular tree species were also evident in the soil adsorption complex and in the contents of plant available and total nutrients. The results can be summarised and generalised: – the forest soil character is reformed at lower and middle altitudes in a relatively short time from the aspect of surface humus accumulation and basic soil chemistry (30–40 years), – birch exhibited the best revitalisation effect among the studied species, – American red oak and Norway spruce humus accumulation potentials were different although the soil chemistry was comparable, – Norway spruce did not show a remarkable degradation effect until now, – on the contrary, European larch appeared as a site degrading species.

ABSTRACT:Yellowing of Norway spruce is a relatively common problem in many regions of the Czech Republic. At some places, it is also connected with forest decline. This unfavourable phenomenon is initiated by several ecological as well as anthropogenic processes. One of the most important is the imbalance of forest stand nutrition. Particular reasons lead to nutrient deficiency, especially deficiency of magnesium. Solution to this undesirable trend is a profound ecological analysis and cause-oriented treatments. Besides decreasing air pollution impacts, fertilisation with deficient nutrients represents a successful treatment in the forest stand management in affected areas. In the area of interest, application of relatively small amounts of appropriate fertiliser (SILVAMIX Mg) led to considerable improvement in the defoliation dynamics and yellowing progress since the first year after application.