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Introduction of silver fir (Abies alba Mill.) as one of the historically important coniferous tree species in Central Europe into allochthonous cultivated forests is an important task for contemporary and future generations of foresters. The aim of our work was to optimize the management of fir in allochthonous cultivated stands of National Park Ceské Švýcarsko formed mainly by Norway spruce (Picea abies /L./Karst.). The effects of light and soil conditions and game on the survival and growth of fir plantations were investigated. Browsing was determined as the limiting factor for fir reintroduction. Assessing the significance of edaphic conditions for the height increment of fir, favourable effect of luvisol could be demonstrated as compared to acidic soil. Canopy openness maximum of 30% and stand basal area of 30 to 43m2/ha with relative direct radiation of up to 45% and relative indirect radiation of up to 55% with prevalence of the diffuse component create optimal environmental conditions for the survival and sustainable growth of fir plantations in the spruce stand in regeneration.
The article describes horizontal structure of the tree layer, natural regeneration, snags and crown projections of natural beech stands on three permanent research plots in the wide altitudinal range in the Krkonoše Mts (Czech Republic). The spatial structure was classified from 1980 to 2010 and subsequently the prediction of spontaneous development with an outlook for 30 years (to 2040) was done by growth simulator. Hopkins-Skellam index, Pielou-Mountford index, Clark-Evans index and Ripley’s K-function were calculated. Further, the vertical structure and total diversity index was evaluated. The horizontal structure of individuals in the tree layer had not changed significantly during the monitored years. Tree spatial pattern of the lowest altitude lying herb-rich beech forest was mostly regular to random, in acidophilous mountain beech forest predominantly random and in fragments of beech groups around the timberline aggregated. Juvenile growth on all investigated plots was distributed aggregated and snags randomly. The horizontal structure of crown projection centroids had always higher values toward the regularity than tree layer and was random to regular. The result of principal component analysis also confirmed that spatial pattern was dependent on the altitude, but also on the number of trees.
Gap regeneration in a European beech (Fagus sylvatica L.) forest reserve was analyzed in relation to within-gap resource heterogeneity and ground vegetation competition. The study was carried out in two one-hectare permanent research plots (PRP) which included five smaller research plots (RP) encompassing two large gaps (500–700 m2), two small gaps (300–400 m2), and location under canopy. The coverage of woody regeneration, ground vegetation, dead wood, seedling density in eight height classes, characteristics of dominant trees of the beech regeneration, and the total thickness of holorganic horizons were measured. Soil moisture and light conditions were also assessed in selected sample plots. The relative direct and diffuse light was estimated by hemispherical photography. Small gaps showed both the highest cover of tree regeneration and the highest density of individuals per hectare. Slightly less regeneration was recorded in large gaps, while under closed canopy, regeneration densities were 5–10 times lower than in small gaps. Beech regeneration cover and the size (diameter and height) of dominant beech seedlings were positively related to relative diffuse light and negatively related to ground vegetation cover. The latter was positively related to diffuse light and soil moisture content. A pronounced statistically significant contrast in the cover and size of beech regeneration in relation to micro-site conditions (diffuse light, cover of graminoids) was only confirmed between sample plots located below canopy cover and those within gaps. Graminoids, in particular Calamagrostis epigejos L., occurred mainly in the large gap centre and along the southernmost edge of the large gap, increasing competition for resources here. The cumulative cover of ground vegetation and regeneration was relatively low (9–56%) compared with more mesic natural beech forests. The indicated negative influence of direct light at the northern gap edge suggests that extension of gaps on comparable sites in managed forest should not proceed in this direction.
The study deals with long-term dynamics of snags and fallen dead wood from 1970 to 2010 in an unmanaged forest ecosystem dominated by European beech in the Bažinky area, Krkonoše National Park (Czech Republic). The volume of dead wood was estimated from 1970 separately for fallen dead wood (logs) and standing dead wood (snags and stumps). Total dead wood volume on permanent research plot (PRP) 6 increased from 41.9 to 241.6 m3 ha–1 and on PRP 7 from 27.7 to 170.0 m3 ha–1. During 40 year case study the mean total volume of fallen dead wood was 193.3 m3 ha–1 (± 29.8 S.E.) and 96.2 m3 ha–1 (± 19.4 S.E.) and the mean total volume of standing dead wood was 17.4 m3 ha–1 (± 3.4 S.E.) and 12.6 m3 ha–1(± 1.4 S.E.) on PRP 6 and PRP 7, respectively. Comparing tree species, the mean volume of fallen dead wood was significantly higher for Norway spruce than for beech in the decomposition class 1 (F(1, 14) = 5.7, P = 0.03) and significantly higher for beech in the decomposition classes 4 (F(1, 14) = 20.4, P < 0.001) and 5 (F(1, 14) = 25.5, P < 0.001). Dead wood was distributed from randomly to aggregated spatial pattern. Despite the rapid decay of beech wood, the amounts of deadwood are likely to increase further during the next decades with continuing disintegration of the forest stand.
European beech is a superior competitor among the trees of Central Europe, often growing in pure stands. We proposed a hypothesis, that once beech has reached dominance in forest community, it's recruitment could become limited due to the gradual accumulation of pathogens attacking seeds and seedlings. We employed data on seed production and germination along with a field experiment to estimate the germination success of beech in two old-growth forests. Beech produced more seeds than the co-occurring coniferous trees, but less than 1% of beechnuts germinated in the next season. In the field experiment, the percentage of decayed beechnuts was 57% in the Carpathians and 61% in the Alps. Most of the dead germinants and decayed beechnuts were infested by fungi. The average number of fungal colonies per one sample in the Carpathians was significantly higher after mast year than one year before, while the differences between the Alps and Carpathians after mast years were statistically not significant. Fungi have been isolated from practically all dead beechnuts and dead germinants. The number of beechnuts per seed trap, the number of germinants around it and the relative number of fungal colonies obtained from plastic boxes placed in the same sample plot were not significantly correlated. The mortality of germinants continued throughout the spring; the number of life germinants in the middle of May amounted to 0.87% of the initial number of beechnuts in the Carpathians and only 0.28% in the Alps. High rates of beechnut and germinant mortality could probably offset the huge reproductive effort of European beech in old-growth stands and limit the possibility to attain absolute dominance by that species. However, our hypothesis that the build-up of fungal pathogens on the forest floor old-growth stands is able to stop the regeneration of beech still needs to be tested using larger data sets.
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