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Zdeněk Vacek, Jan Cukor, Stanislav Vacek, Vilém Podrázský, Rostislav Linda and Jakub Kovařík

Abstract

Land reclamation of post-mining sites strongly influences not only diversity and biomass of frequently studied ground vegetation, but also diversity of forest ecosystem. In most cases, spoil heaps are afforested after coal mining, but some reclaimed sites are left to spontaneous development, such as our study locality – surroundings of the Sokolov town, Czech Republic. Structure, species diversity and production potential were studied on three heap sites, artificially afforested by pedunculate oak (Quercus robur L.), black alder (Alnus glutinosa [L.] Gaertn) and silver birch (Betula pendula Roth) stands, and compared with three permanent research plots (PRP) left to natural succession processes with prevailing European aspen (Populus tremula L.), goat willow (Salix caprea L.) and also with silver birch. The timber production increased from the willow stand (28 m3 ha−1) to birch ones (97 m3 ha−1, all 45 years old). The mean stand volumes were significantly higher on afforested PRPs (74 m3 ha−1) than on succession PRPs (51 m3 ha−1), just as tree diameters. However, in terms of production quality, occurrence of breaks was significantly higher on afforested PRPs (15%) compared to succession PRPs (7%), while the opposite situation was observed in the stem quality. Horizontal structure of trees was regular on afforested PRPs, while spatial pattern on succession PRPs was aggregated. The highest differences in favor of succession PRPs was found in species richness and total stand diversity. These results imply a need for combined approaches in post-mining landscape management to support economic benefit and especially ecological value.

Open access

Robin Ambrož, Stanislav Vacek, Zdeněk Vacek, Jan Král and Igor Štefančík

Abstract

The paper presents the results of the study of the current and simulated structure of beech forests in the Lány game preserve, which is situated in the Křivoklátsko Protected Landscape Area in the Czech Republic. The research was conducted at two permanent research plots (PRP) of 0.25 ha in size in a mature beech forest using the FieldMap technology. Typological, soil and phytocoenological stand characteristics and the history of management of both PRP are comparable; however, they differ in the protection against wildlife. The results demonstrated that deer species including red deer (Cervus elaphus L. - 300 head), sika deer (Cervus nippon nippon Temm. - 300 head), mouflon (Ovis musimon Pallas - 250 head) and fallow deer (Dama dama L. - 300 head) is a limiting factor for successful development of natural regeneration of European beech (Fagus sylvatica L.). Natural regeneration on PRP 1 with wild boar herd (Sus scrofa L. - 150 head) is sufficient in relation to site and stand conditions. On the contrary, there is no regeneration on PRP 2 with the occurrence of deer species. The results of biometric measurements and subsequent predictions by the SIBYLA forest biodynamics simulator indicate that the stands are insignificantly structured, mature, productive beech stands with the absence of individuals in the lower tree layer.

Open access

Jan Král, Stanislav Vacek, Zdeněk Vacek, Tereza Putalová, Daniel Bulušek and Igor Štefančík

Abstract

The structure and health status of waterlogged or peaty spruce (Picea abies [L.] Karst.) forests in the summit parts of the Krkonoše Mts. in the Czech Republic were studied in 1979–2014. The objective was to evaluate the stand structure, dead wood, trend of the health status and productivity on four permanent research plots (PRP) in relation to air pollution (SO2 and NOx concentrations) and climatic conditions (temperatures and precipitation amounts). Stand structure was evaluated on the base of the measured parameters of individual trees on PRP. The health status of trees was evaluated according to foliage, and their vitality was assessed according to their radial growth documented by dendrochronological analyses. The radial growth was negatively correlated with SO2 and NOx concentrations. Stand dynamics during the observation period was characterised by increased tree mortality, the presence of dead wood and reduction of stand density from 1983 to 1992, while the most severe impairment of health status and stand stability occurred in 1982–1987. The foliage mass of living trees has been gradually increasing since 1988, but no pronounced improvement of tree vitality was documented after the decrease in SO2 concentration. However, particularly physiologically weakened spruce trees were attacked by the European spruce bark beetle (Ips typographus). The process of forest damage is manifested not only by foliage reduction but also by symptoms of various necroses on the assimilatory organs. In terms of climatic data, the weather in April had the most important effect on radial growth. Diameter increment showed positive statistically significant correlation with temperature in growing season, but the precipitation effect was low.

Open access

Tereza Putalová, Zdeněk Vacek, Stanislav Vacek, Igor Štefančík, Daniel Bulušek and Jan Král

Abstract

The negative effect of air pollution on mountain spruce stands culminated in the 70s – 90s of the 20th century, when an extensive dieback and disturbance of stands occurred in the Krkonoše Mts., the Czech Republic. Dendrochronological analysis was used on ten permanent research plots established in 1976–1980 to document the dynamics of radial increment of Norway spruce (Picea abies [L.] Karst.). The objective was to determine the effect of SO2, NOX and O3 concentrations and precipitation and temperatures on spruce radial growth in climax forests, waterlogged forests and cultivated forests. The results document the strong depression of diameter increment in the period 1979–1991 caused by synergism of climatic extremes and high SO2 pollution in the 80s and 90s of the 20th century. After 2000 climate had prevailing effect on radial growth. Spruce increment was in positive correlation with temperature, particularly with temperature in the growing season and annual temperature of the current year. In general, temperature had a more significant effect on increment than precipitation, mainly in climax and peaty spruce stands. Diameter increment was in significant negative correlation with SO2 and NOX concentrations in all types of stands. Overall, peaty spruce stands were the most vulnerable to air pollution stress. Low radial increments were caused also by climate extremes, historically by strong frosts and winter desiccation in early spring, nowadays in time of climatic changes by extreme drought. Spruce stands have the ability of quickly responding by tree-ring width to both negative and positive impulses related with air pollution and climate.

Open access

Igor Štefančík, Stanislav Vacek and Vilém Podrázský

Abstract

This work summarizes the history and development of the research on silviculture in the former Czechoslovakia. A different approach of the silviculture research reflecting various site conditions was presented separately for the Bohemian area (later Czech Republic) and Slovakia (later Slovak Republic). The research focused especially on spruce forests in the Czech Republic, and on pure and mixed beech stands in the Slovak Republic. The attention was also paid to the history of research institutions before and after the dissolution of Czechoslovakia. The results achieved so far have been analyzed with particular focus on silviculture of the two most significant tree species in the former Czechoslovakia, namely the Norway spruce and the European beech. At present, the two species dominate the tree species composition of both countries. The spruce comprises 50.5% of the forests in the Czech Republic, and 23.1% in Slovakia. The share of beech is 33.5% in Slovakia, but only 8.3% in the Czech Republic. In both countries, the share of these tree species has changed, in comparison with their original proportion. It is more evident in the Czech Republic than in Slovakia, especially in the case of spruce. For the two tree species, the most important results of a long-term research (including developed original thinning methods) were evaluated separately for each country.

Open access

Zdeněk Vacek, Stanislav Vacek, Lukáš Bílek, Jan Král, Iva Ulbrichová, Jaroslav Simon and Daniel Bulušek

Abstract

The spatial pattern of forest closely affects tree competition that drives the most of processes in forest ecosystems. Therefore, we focused on evaluation of the horizontal structure of high forest, coppice with standards and low forest in hornbeam-oak forests in the Protected Landscape Area Český kras (Czech Republic). The horizontal structure of tree layer individuals with crown projection centroids and natural regeneration was analysed for durmast oak (Quercus petraea (Matt.) Liebl.), European hornbeam (Carpinus betulus L.) and small-leaved linden (Tilia cordata Mill.) stands. Horizontal structure of the tree stems of the studied tree species in high forest was random, in oak it was moderately regular. In coppice with standards it was random in oak, in hornbeam and linden it was aggregated within 3 – 5 m and random up to a larger spacing. In low forest at a distance of 4 – 6 m the horizontal structure of the three studied tree species was aggregated while it was random at a larger spacing. The horizontal structure of natural regeneration was aggregated in all forest types. In coppice with standards and high forest, parent stand had significant negative effect on the natural regeneration at smaller distance (to 1.4 m from the stem). Crown centroids were more regularly distributed than tree stems, especially in low forest (2.0 m) and in linden (2.3 m). Our results contribute to existing knowledge about silvicultural systems and their impact on hornbeam-oak forests with implications for forest management and nature protection.

Open access

Jiří Slanař, Zdeněk Vacek, Stanislav Vacek, Daniel Bulušek, Jan Cukor, Igor Štefančík, Lukáš Bílek and Jan Král

Abstract

The paper deals with development of the natural regeneration of even-aged spruce-beech forests during their transformation to uneven-aged stands with diversified structure at the Jedlový důl area in the Protected Landscape Area Jizerské hory Mts., Czech Republic. Shelterwood management system and free felling policy based on selection principles has been applied there since 1979 with the support of admixed tree species of the natural species composition, especially silver fir (Abies alba Mill.). The research was focuses on structure and development of natural regeneration with the emphasis on ungulate damage and interaction with tree layer from 1979 to 2015. In the course of 36 years, the regeneration structure was diversified towards the close-to-nature tree species composition, spatial and age structure. The number of regeneration recruits increased in average from 941 to 41,669 ind ha-1. During this period share of European beech (Fagus sylvatica L.) significantly (p < 0.01) increased (by 53.6%), while the share of Norway spruce (Picea abies [L.] Karst.) decreased (by 51.5%), such as damage caused by ungulate (by 61.4%) with the highest loses on sycamore maple (Acer pseudoplatanus L.), rowan (Sorbus aucuparia L.) and silver fir. Moreover, the parent trees had a significant negative influence on natural regeneration at smaller spacing (within a 1 - 5 m radius from the stem). Both, regeneration potential and effective role of the tree layer during the forest transformation has been confirmed as important prerequisites for ongoing forest transformation.

Open access

Jan Vopravil, Vilém Podrázský, Tomáš Khel, Ondřej Holubík and Stanislav Vacek

Abstract

This paper deals with the evaluation of the effect of afforestation of previously arable land to soil characteristics changes. One of the main aims was to evaluate the effects of each forest species on the soil structure quality after afforestation. Soil samples were taken at two climatically distinct subregions within the Czech Republic. Based on the different site conditions, two study sites were chosen at each locality for a total of four research sites. Detailed soil survey and basic forest stand inventories were conducted at all four sites. The first locality was established in the Rychnov nad Kněžnou district in the Protected Landscape Area of the Orlické mountains (soil type a Haplic Cambisol). The second locality was established in the Prague-East district (soil type a Haplic Cambisol and a Haplic Stagnosol). Afforestation had a positive influence on the soil physical characteristics which are important for the maintenance of soil stability. Forest cover has a major influence on increasing the soil porosity, by decreasing the reduced bulk density and increasing capillary and gravitational pores, which is crucial. Afforestation was also found to be positively related to increases in soil organic matter content in different forms, both stable and unstable, and tendency of considerable soil organic matter accumulation not only in the layer of surface humus but also in the entire soil profiles of the research sites. The main contributor to soil improvement after afforestation is the formation of stable soil aggregates. This is typical also for spruce and pine cover.

Open access

Zdeněk Vacek, Stanislav Vacek, Jiří Remeš, Igor Štefančík, Dan Bulušek and Lukáš Bílek

Abstract

The paper deals with the research of structure and dynamic development of stands in National Nature Reservation Trčkov, located in Protected Landscape Area Orlické Mts. (Czech Republic). The research was carried out in spruce-beech stand with admixed fir and sycamore maple. Two permanent research plots (PRP 1 and PRP 2), for each with area of 0.25 hectare were chosen as an object of our research. FieldMap technology was used for field measurement. Compared PRP were characterized by the same typological, soil, phytocenology and stand parameters, but different method of protection against game damage. Results showed that deer is considered to be limiting factor for successful development of natural regeneration of autochthonous tree species. The tree species proportion of natural regeneration occurred in PRP 1 with fencing was sufficient, contrary to PRP 2 (outside fencing) owing to site and stand conditions. The results of biometric measurements and predicted simulation by Sibyla growth simulator showed multi-layer stand structure and productive spruce-beech stands with interspersed fir and sycamore maple. We also found depleted phase of regeneration according to frequency and tree species proportion, as well as beginning of grow up stadium, especially related to fir and sycamore proportion and/or beech and spruce. It is concluded that growth visualization and simulation confirmed the hypothesis about long-term effect of game to species, spatial and age structure and development of concerned autochthonous population.