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Princípy ochrany dospelých smrekových porastov pred podkôrnym hmyzom
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... Vo všeobecnosti platí, že najvhodnejšie vlnové dĺžky pre monitoring vegetácie prostredníctvom radaru sa pohybujú v rozmedzí okolo 2 až 6 cm. (Jakuš, Blaženec, 2015;Bucha et al., 2014). ...
The forest is a natural system that fulfills different functions in relation to human society. To ensure long-term maintainability of forest functions it is necessary to monitor of forest on regular basis and subsequently to manage forests based on obtained data. Data from remote sensing are a significant resource for monitoring forests. Compared to other available methods, remote sensing has the advantage of providing contactless acquisition of data. It allows obtaining data from large areas in a short time. echnological improvement constantly brings new innovations also in the remote sensing area. There is a lot of available echnologies, which are possible to use for forest monitoring as a whole or for monitoring of individual trees. This article deals with using remote sensing methods for preserving forest functions. The first part of the article is aimed at using remote sensing echniques for obtaining information about the forest. In the next part of the article most used remote sensing data sources for forest monitoring are noticed.
... Picea abies appears to be the least resilient common tree species in Slovakia in terms of the amplified negative influences of global climate change [1]. The issues of replacing monocultures with more resilient species, a conservative approach in protected areas [2], as well as general knowledge of the climate change impacts on the biosphere are therefore the main reasons why it is an appropriate subject of interest for many dendroclimatological studies. ...
Picea abies L. Karst is undeniably one of the most important tree species growing in Slovakia. In addition to natural mountain spruce forests, monocultures planted in lower areas are also quite common. In this article, we analyze the climate–growth response differences between these two types of spruce stands in the context of local climate change consequences. The study area representing natural mountain spruce forests is located under Osobitá Mt. (Tatra Mountains, Slovakia), while the analyzed low-lying planted monoculture is situated near Biely kríž (Malé Karpaty Mountains, Slovakia). Temporal variation of the dendroclimatological relationships was expressed by the running Spearman correlation coefficient during the observed period 1961–2018. The results showed crucial differences in the dendroclimatological relationships between the selected study areas. For the natural mountain spruce stand, consistent, weak, and positive correlations to the temperature variables were typical, with negative relationships to precipitation during the growing season. In this case, the negative impact of a recent temperature rise was limited. In contrast, the monoculture reacted to the temperature variation during the growing season with fluctuations, while in the case of precipitation, almost no dependence was found. Such incoherency may be a consequence of worsened health conditions, as well as insufficient resiliency to climate-driven stress. The importance of this paper is in its wide applicability, mainly in forestry.
During the past 20 years, the surroundings of the Čertovica saddle were extensively deforested. In this conference paper, we provide a summary of all drivers of this land cover change. Identification of the drivers and estimation of the spatial extent of their consequences were executed using the freely available platform Global Forest Watch, Landsat imagery, high-resolution ortophotomosaics, and the scientific literature. For this purpose, a 16 km 2 study area was delimitated with the Čertovica saddle in its central part. At first, windstorm Alžbeta hit the study area, resulting in 8% being deforested. After Kyrill and Filip windstorm in 2007, bark beetle infestation and subsequent clear-cutting took place. During 2008-2012, 26% of the study area was deforested. After then, reforestation became the prevalent process. Knowledge of deforestation triggers is crucial for further geoecological analysis, including identification of land cover changes, as well as geostatistical modelling using logistic regression and generalized additive models.
High winds and the subsequent infestation of subcortical insect are considered to be the most extensive types of large natural disturbances in the Central European forests. In this paper, we focus on the landscape dynamics of two representative mountain areas of Slovakia, which have been affected by aforementioned natural disturbances during last two decades. For example, on 19 November 2004, the bora caused significant damage to more than 126 km2 of spruce forests in the Tatra National Park (TANAP). Several wind-related events also affected sites in the National Park Low Tatras (NAPALT). Monitoring of related land cover changes during years 2000–2019 was based on CORINE Land Cover data and methodology set up on satellite and aerial images interpretation, on detailed land cover interpretation (1:10,000) for the local case studies, as well as on the results of field research and forestry databases. The dynamics of forest recovery are different in the clear-cuts (usually with subsequent tree planting) and in the naturally developing forest. The area in the vicinity of Tatranská Lonmnica encroaching on the Studená dolina National Nature Reserve in TANAP represents a trend of the gradual return of young forest. The area of Čertovica on the border between NAPALT and its buffer zone are characterized by an increase in clear-cut sites with potentially increasing soil erosion risk, due to repeated wind disasters and widening of bark beetle. Proposed detailed, large-scale approach is being barely used, when considering recent studies dealing with the natural disturbances.
Root decay infection and potential relations to Ips typographus L. outbreaks in the Šumava Mts. (Bohemian Forest) were monitored in 3 permanent sample plots. As an originator of root decays honey fungus predominated, in particular cases Heterobasidion annosum (FR.) BREF. was also recorded. As for honey fungus species, Armillaria ostoyae (ROMAGN.) HERINK predominated, however, A. cepistipes VELENOVSKÝ and A. borealis MARXMÜLLER et KORHONEN were also determined. Other wood-destroying fungi were also recorded, e.g. Stereum sanguinolentum (ALB. & SCHW.: FR.) FR. and Climacocystis borealis (FR.) KOTL. Although Armillaria foci were localized directly in a forest edge after bark beetle disaster, it is not possible to state definite relationships between Ips typographus L. invasion and root system infection by Armillaria. The found out rate of infection is, with respect to an altitude over 1,100 m, extremely high not corresponding to existing knowledge on the behaviour of Armillaria in the region of Central Europe. The extent of Norway spruce infection by Armillaria ostoyae (ROMAGN.) HERINK can give evidence of the chronic stress load of spruce trees in the area.
The pathogens of Ips duplicatus were studied in three outbreak areas, i.e. on the border of Bialowieza Primeval Forest (N Poland), in an Armillaria root rot area in the eastern Czech Republic and on the southern edge of the beetle's range in the Bile Karpaty Mts. and Javorníky Mts. (SE Czech Republic). In all three areas I. duplicatus lives in association with I. typographus. The pathogens found were Chytridiopsis typographi, Larssoniella duplicati, Gregarina typographi, and Pichia sp. N Poland populations of I. duplicatus, coexisting with I. typographus, had a high endemic level 21.5% and 18.9% of C. typographi in both hosts. Also, I. duplicatus had a rather high infection level of L. duplicati (30%). This pathogen was not present in I. typographus. In the E Czech Republic both bark beetles contained C. typographi in low level, with a maximum of 3% infection in I. duplicatus and 3.6% in I. typographus. We did not find infected beetles of both species at one locality. The average level of infestation of I. duplicatus with L. duplicati was 37.7%. A bit different situation was found for the most southern range of I. duplicatus (SE Czech Republic), where the insect's distribution mostly depends on spruce forests. Although the infection level of C. typographi is similar to E Czech Republic in both bark beetles, in contrary, only 4.4% beetles were infected by L. duplicati. Two pathogens, Gregarina typographi, and Pichia sp., appear only as minor admixture, apparently related to local population densities. The infection of I. duplicatus with L. duplicati frequently reaches a high level in both throughout the range of I. duplicatus and the season.
Automatic identification of forest patches disturbed by the spruce bark beetle Ips typographus L. is crucial to reveal the rules of following bark beetle outbreaks on the landscape scale. Landsat imagery provides free resources to outline past and present gradations of bark beetle outbreaks (BBOs). The objective of this study is to identify the most sensitive vegetation index through different method of vegetation index differencing to identify past and actual bark beetle outbreaks. Six Landsat Thematic Mapper (TM) images, from 2005–2009 and 2011, were converted into selected vegetation indices (VIs) sensitive to conifer tree health in a Norway spruce–dominated forest in the High Tatra Mountains. The Vegetation Condition Index (VCI), Moisture Stress Index (MSI), Normalised Difference Moisture Index (NDMI), Normalised Difference Vegetation Index (NDVI), Disturbance Index (DI) and Changed Disturbance Index (DI´) were calculated separately for every year, and the methodology of vegetation index differencing was applied to multiple two-year time periods (2005–2006, 2006–2007, 2007–2008, 2008–2009 and 2010–2011), thus producing the Changed Vegetation Index (ΔVI). A set of thresholds was established on ΔVI to classify disturbed and undisturbed forest due to BBOs; the sensitivity of different VIs to identify BBO was equally evaluated. The highest accuracies of classifications were reached in 2007 and 2011 (kappa index of agreement >70% and >40%, respectively), which were characterised by an epidemic phase of a BBO. All selected VIs were highly sensitive to BBOs, except for NDVI. The stable threshold value for change detection is not widely applicable to detect past forest disturbances caused by bark beetles, however. Finally, for further research of the epidemic phases of BBOs, we recommend the utilisation of the vegetation indices VCI, MSI and NDMI to detect BBOs because of their simplicity and easy interpretability.
The chapter desribes important non-coleopteran species, which damage the living trees in Europe.
This case study reports the recent history and evaluates the socio-economic constraints on nature conservation in the Bohemian Forest, which is the largest natural wilderness area in the central European cultural landscape. This gradually occurred over the past half of century, when nature was allowed to reclaim the most valuable parts along the common Czech–German border and the national parks (NP) were established: the Bavarian Forest NP in Germany (in 1970) and the Šumava NP in the Czech Republic (1991). Unfortunately, since the very beginning of the Šumava NP, its status has been questioned, compromised or debated, and it never received clear political support. Discussions about its future have become never-ending and were only on the appropriate management of the forests, i.e. “non-intervention” management versus “necessary” bark-beetle control. The “bark beetle problem”, however, is a wildcard issue that has obscured much more complex problems. This paper is the first attempt to describe the main obstacles and offer some solutions for making the Šumava NP a successful and sustainable project.
A faunistic study of bark beetles species occurring at Mt. Smrčina/Hochficht in the southern part of the Bohemian Forest was carried out in 2009, two years after the Kyrill hurricane. The study area was located on the border between the Šumava NP in the Czech Republic and private forests in Austria. The manage-ment policy is non-intervention in the core zone of the Šumava NP, whereas commercial forest management is applied on the Austrian side of the border. The original survey focusing on the migration of the bark beetles (primarily Ips typographus) in the border area recorded high number of different species and of-fered opportunity to study also the species diversity. This study presents its faunistic results. Species diver-sity was studied along three transects. There were five monitoring sites along each transect. At each site traps were arranged in the form of two crosses in which there was one pheromone trap ('active trap') and nine traps without pheromone ('passive trap'). Of the total of 150 traps set in the study area only fifteen were baited with pheromone. Eighteen species belonging to the family Scolytinae were caught by the traps during the five months of this study. Five of the species feed only on spruce, eleven are polyphagous feeding on Picea spp., Pinus spp., Abies alba, and Larix decidua. In addition, there were two species, Scolytus in-tricatus and Xyloterus domesticus, which probably feed on old maples growing in historically grazed parts of the forest. Ips typographus, Pityogenes chalcographus, Dryocoetes autographus, and Dryocoetes hec-tographus were the most common species. The first two species dominated the catches of the traps baited with pheromone. Several rare species, including Pityogenes conjunctus, were also caught. Species diver-sity and ecology of recorded bark beetles species are discussed to support current debates about more ap-propriate management of the forests in the National Park. INTRODUCTION Natural disturbances are important determinants of forest development. Both wind and in-sect outbreaks are very important in central European forests (FRELICH 2002). Bark beetles (Coleoptera: Curculionidae: Scolytinae), such as Ips typographus and Pityogenes chal-cographus, play crucial roles in the dynamics of Norway spruce forests in Europe (CHRIS-TIANSEN & BAKKE 1988, WERMELINGER 2004, SVOBODA et al. 2010). The role of particular
Seasonal flight activity of Ips duplicatus (Sahlberg, 1836) was monitored from 1996 to 2000 with Theysohn traps baited with the synthetic lures Ipsdienol and E-myrcenol. Flight activity of Ips typographic was monitored concurrently with traps baited with (S)-cis-verbenol, 2-methyl-3-buten-2-ol and Ips-dienol. Traps were placed 15 m apart in groups (2-10 traps) along the border of the mature forest stands of Norway spruce (Picea abies) near the villages of Pustá Polom, Kyjovice and Výškovice in Nízký Jeseník highlands and at the village of Bystřice nad Olší in Jablunkovská brázda valley. The traps were checked weekly. Two generations per year of I. duplicatus are common in C Europe. Three generations a year are possible as a result of a very hot summer Triggering of swarming in I. duplicatus depends on the temperature in April like in I. typographus. The development of I. duplicatus and I. typographus is probably identical with the same seasonal distribution (homogeneity of the cumulative flight curves were assessed with the Chow test). Under suitable weather conditions the first generation of both species usually swarms in May and the second in July. The third generation of I. duplicatus would swarm during August or September.