Wyniki wyszukiwania

1

Dynamika poskozeni reliktnich boru v CHKO Broumovsko

100%

Vacek S., Podrazsky V.

Szczeliniec

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1996

159-165

2

Stav lesnich pud nad piskovcovych utvarech v CHKO Broumovsko

100%

Podrazsky V., Vacek S.

Szczeliniec

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1996

95-100

3

Struktura a vyvoj prirodnich smrkovych porostu v Krkonosich

100%

Vacek S., Podrazsky V.

Zeszyty Naukowe Akademii Rolniczej w Krakowie. Sesja Naukowa

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1998

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tom 56

4

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

71%

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

Dendrobiology

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2015

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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.

5

The effects of climatic conditions and forest site types on disintegration rates in Picea abies occurring at the Modrava Peat Bogs in the Šumava National Park

61%

Krejci F., Vacek S., Bilek L., Mikeska M., Hejcmanova P., Vacek Z.

Dendrobiology

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2013

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tom 70

A survey of mountain spruce stand development in the Šumava National Park on Modrava peat bogs on an area of 1,370 ha resulting from spruce bark beetle outbreaks was performedby means of visual evaluation of aerial photographs from the period 1991–2000. In addition, our study addressed the influence of climatic effects (period1984–2000) andthe effect of forest site (climax, waterloggedandpeaty spruce stands) on the dynamics of disintegration of forest stands. We showed that new infestations were predominantly foundat short distances from their source, the average value was estimatedto be 40–60 m, whereas the longest distance for annual progress in west to east direction was estimated to be 120 m. Differences in the dynamics of disintegration between waterlogged stands and drier stands were confirmed. There was a positive relationship between the average temperature in the 2nd quarter of monitoring years which was registered as the period of the onset of bark beetle development and the proportion of degraded area in Norway spruce stands. Moreover, pronounced winter desiccation in January 1993 was a triggering mechanism with crucial importance for the outbreak of bark beetle in the studied area.

6

The dynamics and structure of dead wood in natural spruce-beech forest stand - a 40 year case study in the Krkonose National Park

61%

Vacek S., Vacek Z., Bilek L., Hejcmanova P., Sticha V., Remes J.

Dendrobiology

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2015

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tom 73

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.

7

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

51%

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

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2015

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tom 63

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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.

8

Structural diversity and production of alder stands on former agricultural land at high altitudes

51%

Vacek Z., Vacek S., Podrazsky V., Kral J., Bulusek D., Putalova T., Balas M., Kalouskova I., Schwarz O.

Dendrobiology

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2016

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tom 75

The paper deals with the structural diversity and production of a less frequently studied type of alder stands originated on former agricultural lands in the 1950s, established partly by plantation and partly by natural succession in the area of the Krkonoše Mts. and the Orlické hory Mts. (Czech Republic). Four permanent research plots (PRP) were established at sites where Black alder (Alnus glutinosa L. Gaertn.) and Grey alder (Alnus incana L. Moench.) naturally occurs, each plot of 0.25 ha in size. The aim of the study was to evaluate the structure and development of the alder stands with respect to biodiversity, horizontal, vertical and species structure, diameter increment with emphasis on climate factors, and the quantity and quality of timber production. The results document low diversification of the studied stands in the PRPs. The horizontal structure is defined as random and clumped at sites at the highest altitude with high water table. The number of living trees with DBH ≥ 4 cm ranges between 556 to 828 trees ha-1 with the relative stand density index (SDI) 0.67–0.77. The stand volume ranges from 247 to 393 m3 ha–1, and decreases with higher altitudes. Low temperatures is limiting factor for radial growth in the high mountain areas, respectively low precipitation in the middle lands. Owing to a rather specific site character, as especially the spring area, the stands exhibit only average production, but the production quality is generally high. The quality timber is suitable for industrial use; the rot-affected trunk base parts usable for fuel represent only approximately 16%.

9

Stand dynamics in natural Scots pine forests as a model for adaptation management?

51%

Vacek S., Vacek Z., Bilek L., Remeš J., Hůnová I., Bulušek D., Král J., Brichta J.

Dendrobiology

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2019

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tom 82

10

Long-term effect of climate and air pollution on health status and growth of Picea abies (L.) Karst. peaty forests in the Black Triangle region

51%

Vacek Z., Vacek S., Prokůpková A., Bulušek D., Podrázský V., Hůnová I., Putalová T., Král J.

Dendrobiology

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2020

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tom 83

11

Effect of vegetation on natural regeneration of mixed silver fir forests in lowlands: a case study from the Rogów region in Poland

51%

Prokupkova A., Brichta J., Vacek Z., Bielak K., Andrzejczyk T., Vacek S., Stefancík I., Bilek L., Fuchs Z.

Sylwan

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2021

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tom 165

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nr 11

12

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

42%

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

Dendrobiology

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2022

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tom 87

Ograniczanie wyników

Dynamika poskozeni reliktnich boru v CHKO Broumovsko

Stav lesnich pud nad piskovcovych utvarech v CHKO Broumovsko

Struktura a vyvoj prirodnich smrkovych porostu v Krkonosich

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

The effects of climatic conditions and forest site types on disintegration rates in Picea abies occurring at the Modrava Peat Bogs in the Šumava National Park

The dynamics and structure of dead wood in natural spruce-beech forest stand - a 40 year case study in the Krkonose National Park

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

Structural diversity and production of alder stands on former agricultural land at high altitudes

Stand dynamics in natural Scots pine forests as a model for adaptation management?

Long-term effect of climate and air pollution on health status and growth of Picea abies (L.) Karst. peaty forests in the Black Triangle region

Effect of vegetation on natural regeneration of mixed silver fir forests in lowlands: a case study from the Rogów region in Poland

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