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Changes in horizontal structure of natural beech forests on an altitudinal gradient in the Sudetes

100%

Vacek Z., Vacek S., Bilek L., Remes J., Stefancik I.

Dendrobiology

2015

tom 73

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.

Effect of tree layer and microsite on the variability of natural regeneration in autochthonous beech forests

72%

Vacek Z., Vacek S., Podrazsky V., Bilek L., Stefancik I., Moser W. K., Bulusek D., Kral J., Remes J., Kralicek I.

Polish Journal of Ecology

2015

tom 63

nr 2

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.

Effects of environmental factors and management on dynamics of mixed calcareous forests under climate change in Central European lowlands

58%

Vancura K., Simkova M., Vacek Z., Vacek S., Gallo J., Simunek V., Podrazsky V., Stefancik I., Hajek V., Prokupkova A., Kralicek I.

Dendrobiology

2022

tom 87

Ograniczanie wyników

2 Dendrobiology

1 Polish Journal of Ecology

3 Stefancik I.

3 Vacek S.

3 Vacek Z.

2 Bilek L.

2 Kralicek I.

2 Podrazsky V.

2 Remes J.

1 Bulusek D.

1 Gallo J.

1 Hajek V.

1 Kral J.

1 Moser W. K.

1 Prokupkova A.

1 Simkova M.

1 Simunek V.

1 Vancura K.

1 2022

2 2015

Wyniki wyszukiwania

Changes in horizontal structure of natural beech forests on an altitudinal gradient in the Sudetes

Effect of tree layer and microsite on the variability of natural regeneration in autochthonous beech forests

Effects of environmental factors and management on dynamics of mixed calcareous forests under climate change in Central European lowlands