Jozef Konôpka and Bohdan Konôpka
Koncepcia ïalšieho výskumu ochrany lesa na Slovensku so zreteľom na biologický boj proti škodcom
Analyzujú sa príčiny a charakterizuje sa proces poškodenia lesných porastov na Slovensku. Osobitná pozornosť sa venuje analýze priestorového a časového ohrozenia lesných ekosystémov škodlivými činiteľmi. Uvádzajú sa výsledky rajonizácie ekologických podmienok potenciálnej aktivity škodlivých činiteľov. Ďalej závery, ktoré vyplynuli z rozboru vulnerability drevín a porastov podľa ich rastových fáz. Aj keď sa tejto problematike na Slovensku najmä v období od 60. do 80. rokov minulého storočia venovala určitá pozornosť, v danom období proces klimatickej zmeny a jeho následky neboli ešte známe, resp. významné. Uvádzajú sa najnovšie poznatky o vplyve klimatickej zmeny na lesné ekosystémy, najmä na ich ohrozenie škodlivými činiteľmi. V nadväznosti na to sa navrhuje nová stratégia a koncepcia ďalšieho výskumu. Ide o nové komplexné spracovanie problematiky priestorového a časového ohrozenia drevín a porastov v podmienkach klimatickej zmeny. Ďalej o vyselektovanie okruhov kde prichádza do úvahy ochrana lesa metódami biologického boja s biotickými škodcami. Nakoniec o vymedzenie podmienok, ktoré rozhodujú o úspešnosti či efektívnosti použitia tohto spôsobu boja.
Bohdan Konôpka and Erika Gömöryová
Peter Kaštier, Jozef Konôpka and Bohdan Konôpka
Strategic aims and priorities of forestry and game management in Slovakia are characterised. Using current knowledge in the field, common bases for both target sectors are introduced and possibilities for harmonisation of their interests are explained. Development of mutual relationship between forestry and game management is analysed and the causes of existing discrepancies are shown. The main reason of the discrepancies is unfavourable development of ungulate game population and high damage to forests stands caused by game browsing. The final part of the paper presents the recommendations for practical measures to be taken for reaching accordance between both sectors, eventually measures for achieving the primary goal to support all-society’s interests in this field. We base our suggestions on an assumption that both forestry and game management accept the proposed measures, or more precisely the measures will be implemented through mutual collaboration and integration.
Jozef Konôpka, Rudolf Midriak and Bohdan Konôpka
The contribution is published on the occasion of the 120th anniversary of the establishment of a forestry research organisation in Slovakia and the 100th anniversary of the establishment of the Czechoslovak Republic. We present important forestry research works, which were written by former (no longer alive) workers of the Forest Research Institute (FRI) in Zvolen in the second half of 20th century. The works (30 works in total) were divided into seven scientific areas: biology and silviculture (five works), forest protection (four works), forest management (five works), forestry mechanisation and harvest-production technologies (four works), forestry economics (five works), hunting (three works), natural environment (four works). First, summary information on selected works in a specific area was presented. Then, individual works from the specific scientific areas were characterised in more detail. Their value for the development of science and research as well as for the practical forestry was presented. Moreover, their importance for the present time was addressed. The paper presents only a very limited selection of a great number of works by FRI workers published in the second half of 20th century. The table with the information on the periods, when the individual significant researchers worked at FRI, is presented at the end of the paper.
Bohdan Konôpka and Jozef Pajtík
The study focuses on two young stands of European beech (Fagus sylvatica) and Norway spruce (Picea abies) of the same age (12-yearold) with similar sized trees grown at near identical sites. After performing a destructive sampling technique which included all tree compartments except fine roots; allometric equations were constructed for all tree components. Diameter at stem base (do) was utilized as an independent variable for the equations. The models expressed not only biomass of woody parts (branches, stem and coarse roots) and foliage but also foliage area and specific leaf area (SLA). Results indicate that the basic morphological properties of foliage vary in both species along the vertical crown profile. In spruce, contrasting values of needle area and SLA were recorded among needle sets (based on year of establishment). On a tree level, both spruce and beech had similar foliage areas however, beech had a larger biomass comprising of woody parts while spruce biomass was dominated by foliage. Therefore the leaf mass ratio (LMR) defined as the ratio between foliage biomass and total tree biomass, as well as leaf area ratio (LAR) defined as the ratio between leaf area and total tree biomass were much larger in spruce than in beech species. On a stand level, spruce manifested a higher value (18.64 m2.m−2) of leaf area index (LAI) than beech (12.77 m2.m−2). Moreover, while the biomass of foliage was 4.6 times higher in spruce than in beech, total biomass of woody parts were similar in both stands. These contrasts indicate very different growth strategies and biomass allocations between beech and spruce at the young growth stages
František Máliš, Bohdan Konôpka and Miriam Maľová
We investigated the above- and below-ground standing biomass and production of plant communities dominated by bushgrass (Calamagrostis epigejos) colonizing forest clearings created by harvesting beechspruce forest stands. Above-ground living biomass of these communities was 6.6 t.ha-1, while above-ground litter made up 5.6 t.ha-1. Below-ground standing biomass was 6.6 t.ha-1 and production was 1.6 t.ha-1. Inter-annual fluctuations in production were rather high and did not clearly follow weather alternations. We hypothesize about some of the reasons for this. A negative correlation between litter and production of bushgrass rhizomes and root were found. The amount of bushgrass above-ground biomass did not affect species’ richness, but a higher amount of its roots inhibited occurrence of other species, especially other dominants in the forest clearings Epilobium angustifolium and Rubus idaeus. The bushgrass produced rhizomes mainly at micro-sites with higher proportions to other species. The number and average length of the bushgrass blades are related to its above-ground biomass. We conclude that the competition between bushgrass and other species takes place most heavily in the top soil layer. Biomass production of bushgrass communities is not sensitive to weather patterns under the conditions of beech-spruce forest clearings. In terms of the carbon accumulation and nutrient cycling, these communities have an important role in certain periods of forest life.
Bohdan Konôpka, Jozef Pajtík, Michal Bošeľa, Tomáš Hlásny and Zuzana Sitková
We investigated the seasonal dynamics of height increment, as well as total annual height increment, in 2009-2013 on young stands of beech and spruce grown at the same site. The results showed that the inter-annual dynamics of basic stand characteristics, especially tree density, were more obvious in spruce than in beech stands. Much higher tree mortality in spruce was explained by a lower light intensity under the spruce stand canopy and higher tolerance of beech to shade. Large interspecific differences were also found in the timing of height increment. Specifically, the height increment of beech trees started earlier than those of spruce. Moreover, the terminal grew for longer in spruce (nearly 70 days) compared to beech (about 45 days). The comparisons between the courses of the height increment and the ambient factors suggested that global radiation played a principal role. In the beech stand, the maximum height increment rate occurred during the same days as the maximal global radiation in 2009 and 2011, while a decline of the height increment occurred simultaneously with a depression in global radiation in 2012. As for the spruce stand, its one-peak maxima in height increment were related to the maximum of global radiation in 2009 and in 2012. On the other hand, double-peak courses of height increment in 2010 and 2011 may have been related to sudden declines in global radiation. Interspecific differences in height increment timing might play a certain role in cases of unfavourable weather conditions, e.g. drought episodes in the middle part of the growing season when the height increment would be accomplished in beech but would still be ongoing in spruce.
Vladimír Šebeň, Bohdan Konôpka and Jozef Pajtík
In Slovakia, the contribution of young stands to the total forest area has been increasing in the last decade. However, scientific attention to these stands was previously very sparse and they were usually not included in local and country carbon stock estimates. Therefore, we focused on the calculation of tree biomass and necromass in young beech and spruce stands as well as on their development during the period of nine years (aged from 4 to 12 years). For the calculation, we implemented allometric equations using tree diameter and height as independent variables. The results showed very dynamic changes in biomass (carbon) stock. Specifically, tree biomass increased in the period of 9 years from about 2,000 g to 15,000 g (i.e. cca 1,000 to 7,500 g of carbon) per m2 in beech, and from 4,500 to 12,000 g (cca 2,300 to 6,000 g of carbon) per m2 in the spruce stand. At the same time, the amount of biomass (fixed carbon) was only slightly larger than the accumulated quantity of necromass (carbon loss from living trees). It means that a large portion of carbon was allocated to necromass. We found that not only the foliage fall but also the mass of dead trees, a result of intensive competition, was an important path of carbon flux to necromass. The results proved that although young forests fix much less carbon in their biomass than old stands, they can represent large carbon flux via annual increment of necromass. This indicates that young stands should not be omitted in forest carbon balance estimates of the country.
Jozef Pajtík, Bohdan Konôpka and Róbert Marušák
One of the expected consequences of climate change and its inherent phenomena to forest ecosystems is the gradual modification of their tree species composition (i.e. expansion of resistant species instead of less resistant ones). Climate change accompanied with increasing temperatures and a lack of precipitations may present a threat especially to spruce stands in the European part of the temperate zone. European beech is one of the possible forest tree species which might replace the potentially endangered spruce. In this paper, we observed, by using a combination of continual measurements and destructive whole-tree sampling, standing stocks of above-ground biomass (i.e. stem, branches, and foliage) and its annual net primary productivity (NPP) in naturally regenerated young stands of beech and spruce. We intentionally selected a site where the changing climate conditions are better suited to the ecological demands of beech rather than spruce (the species is dominant in the observed area). We recorded only small differences in the standing stock of stems of the beech, if based on tons per ha. However, this is in favor of spruce if based on cubic meters per ha. The largest difference between the species was found for the standing stock of foliage, spruce retained three times the biomass of beech. Also, beech allocated more carbohydrates to stem than spruce. On the other hand, we estimated nearly the same production of foliages and branches in both stands.