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Growing Norway spruce at relatively warmer and drier conditions poses a threat of its die-off. Despite recent focus of silviculture on conversion of tree species composition, foresters still have to cope with existence of monospecific young spruce stands. Four thinning experiments were established at lower altitudes to investigate a response of stand characteristics to early thinning. Experimental thinning accelerated diameter increment of spruce crop trees significantly. Thinning also slowed pace of the slenderness ratio development thus impacting on the h/d values positively. Live crowns got short more slowly following thinning compared to control. Spruce stands at lower altitudes must be thinned as early as possible when mean height of dominant trees achieves 5 m. Given the risk of growing spruce at lower sites, all suitable tree species should be left on site. Spruce should be no longer grown in monospecific stand over the whole rotation, however silviculture measures should focus on maintenance of its share in future species composition.
The subject of the research is to increase the stability of beech forests (Fagus sylvatica L.) by transforming them into forests of diameter classes. At the beginning of the experiment, the stands were 80 years old. Their transformation into the selection forest or the mosaic structure begun 24 years ago. The aim of the research was to obtain the information necessary for the design of models of beech selection forest and beech mosaic stand. The analyzed stands had a moderately differentiated height structure at the beginning of the experiment. In the permanent research plots (PRP 1-2) during 24 years of conversion and application of selective thinning and later selective cutting with an intensity of 14–18%, the phase of refinement of the selection structure took place. Based on the data analysis, we derived beech forest model with a target diameter of 50 cm, an optimal volume of 307 m3 ha-1 and a basal area of 27 m2 ha-1. The conversion of beech stand on PRP 3 to the mosaic structure resulted in the proposal of the model characterized by the Weibull diameter distribution (target diameter 50 cm, basal area 31 m2 ha-1, model stand volume 392 m3 ha-1).
The concept of zonality (zonal concept) or azonality of vegetation has been well known for a long time all over the world. In the Czech Republic (CZ), this topic is usually presented in a context of (forest or forest site) ecological classification systems, called informally “forest typology” or officially “the Czech Forest Ecosystem Classification”. Expert-based vegetation zonality has not been tested so far. There is even no relevant ecologically-based review of the concept and linked ecological principles behind classification systems. The latest modest note dealing with the zonal concept has been published along with the Notice 298/2018 of Forest Law (Typology table). This review summarizes (i) brief history on the zonal concept, (ii) definition of zonal and azonal vegetation, and description of parameters of a zonal site, (iii) approaches of (forest) classification systems around the world, and (iv) main principles of the Czech Forest Ecosystem Classification. Results of this review should be used as a theoretical basis for a next rigorous analysis of the concept and system units, based on data, sampled during the second cycle of the National Forest Inventory 2011–2015.
Poisoned trap trees and tripods started to be applied in defence along with the development of insecticides and pheromones whose negative impacts on the non-target fauna of invertebrates should be, however, taken into account together with the efficiency of these defence measures. In spruce stands with the differentiated mass outbreak base (Forest District Nové Město na Moravě, Czech Republic) we tested lying poisoned trap trees of 4 m in length and tripods with the Storanet net sized 1.5 and 1.9 m2 that was baited with the IT Ecolure pheromone. The efficiency of trapping I. typographus with the poisoned trap trees was statistically significantly higher than that of trapping the beetle with the tripods with the Storanet at both spring and summer swarming. The efficiency of defence measures was only 20–30% in relation to trees infested by bark beetles. A higher number of killed non-target arthropods was recorded on the tripods with the Storanet than on the poisoned trap trees. The IT Ecolure pheromone probably caused an increased occurrence of Acanthocinus aedilis, Molorchus minor, Thanasimus formicarius and T. femoralis species.
The purpose of this study was to investigate the possibilities of using objective methods of DNA analysis to verify the declared origin of reproductive material of Scots pine in terms of the Czech Republic. Monitoring of reproductive material identity was carried out during four years, i.e., from seed collection to transplanted plants production. Reference samples from the 40 sets of reproductive material were obtained, analyses of microsatellite markers were performed, and the genetic compositions of sets were compared after statistical processing. Altogether, DNA analyses were performed on 2390 samples of plant material from 10 selected sources of forest reproductive material (units of forest reproductive material). Seven optimally polymorphic markers with sufficient informative value were selected for the subsequent evaluation of the genetic structure of the monitored sets of Scots pine reproductive material by Bayesian clustering. Using the performed Structure analysis, the obtained profiles of 10 monitored units of reproductive material (4 sample sets from one units) of different origin were distinguishable from each other. Thus, these methodological procedures could be used in the state control systems to certify the origin of forest reproductive materiál and increase consumer protection of forest owners and nursery production in the Czech Republic.
Two-stage forest regeneration using preparatory stands presents potentially suitable way of an introduction of silver fir (Abies alba) in largescaled clear-cut areas of calamity origin. The objective of this study was the verification of four-year-old fir underplanting reactions at nutrient rich site to the preparatory stands environment featuring three pioneering species of various stocking density (5, 7, 10) compared with plantings in small area clearing (0.1 ha). The fir mortalities were low both in all stand treatments and in the clearing. The fir height and root diameter increments under birches declined with higher stocking density. Under rowan, the highest increments occurred under preparatory stand with stocking density of 7. Minimal fir increment reactions to the various stocking density of the preparatory stands were observed under alder trees. The development of the crown width mostly correlated with the fir height. Development of the needle lengths, depending on the stocking density of preparatory stands, differed under birches from rowan shelter, while there were no differences in this parameter under alder treatments. The research showed that in present conditions fir plantings in small area clearings or under about 15-year-old preparatory birch stands, having stocking density reduced to one half, can be recommended from fir prosperity perspective.
The presented article deals with the catchments of three streams, which are right-hand tributaries of the Černá Opava river, where new foresthydrology research activities of the Forestry and Game Management Research Institute and Czech Hydrometeorological Institute begun. The focus of the work in the years 2019–2021 was on field research and measurements, spatial analyses in GIS and mathematical modelling using rainfall-runoff and hydrodynamic models, thus we can mention HEC-HMS, SIMWE and MIKE SHE/11 models among others. The article provides an overview of current outputs from these activities. It also outlines the issues of the impact of land use, forest health including its extreme phases on hydrological conditions and the response of river basins to precipitation inputs. Besides that, the issue of variable contribution areas of the river basins and the possibilities of their research at the level of monitoring (e.g. measurement of flows and volumetric soil moisture) and mathematical modelling using complex fully distributed precipitation-runoff models are discussed as well. At the same time, basic hydrological characteristics of the studied catchments were provided.
The paper deals with production capacity of selected pioneer species – Silver birch, black alder, European aspen and goat willow. The review focused on these fields of research: ecology requirements and natural distribution of discussed species; their growth and yield; effect of site conditions on growth and production (the main goal) and yield comparison of these species. The vigorous growth and marketable production of Silver birch is considered on fertile soils with adequate moisture and air content. Warmer climate and lower altitudes create optimum growing conditions for European aspen. Rich sites and middle altitude are considered optimal site conditions for goat willow as well. The productivity of black alder is greatest on riverside site. The mean annual volume increment (MAI) for analysed species varied from 4 to 10 (12) m3/ha, for goat willow relevant data are missing. Rotation period for these species should not be longer than 55 (60) years due to the risk of heart rot occurrence. The highest potential for biomass production shows Silver birch with maximum annual increment ranged from 5 to 7 t/ha within the age of 15–25 years. Faster growth in the young and shorter rotation period advantages production of pioneer species contrary to common shade tolerate species as a spruce, fir and beech, in the process of reforestation of large clearings.