pavel mezei | UEL SAV (original) (raw)

Papers by pavel mezei

Research paper thumbnail of Contrasting Norway spruce disturbance dynamics in managed forests and strict forest reserves in Slovakia

Forestry

Forest disturbances are intensifying globally, yet regional drivers of these dynamics remain poor... more Forest disturbances are intensifying globally, yet regional drivers of these dynamics remain poorly understood. We investigated recent disturbance intensities in Norway spruce (Picea abies L.) forests in Slovakia (Central Europe) with different management objectives in 2000–2017 based on Landsat imagery. We focused on 122 strict reserves without any management, their actively managed surroundings (500 m and 2000 m buffers), and managed production forests beyond the buffer areas. We used generalized additive mixed models to test for differences in temporal trends of disturbance intensity among these management categories. We found that disturbance intensity was increasing in all management categories during the studied period. The increase was more pronounced in the managed forests (compound annual disturbance rate 1.76% year−1) and the 2000 m buffer (2.21% year−1) than in the strict reserves (0.58% year−1). The predicted cumulative disturbance during the 18-year period was 9.9% in t...

Research paper thumbnail of Infestation Patterns of Multi-Species Coniferous Forests by Two Bark Beetle Species in Kunashir Island in the Far East

Social Science Research Network, 2022

Research paper thumbnail of Wind Damage and Temperature Effect on Tree Mortality Caused by Ips typographus L.: Phase Transition Model

Forests, 2022

The aim of this study was to develop methods for constructing a simple model describing tree mort... more The aim of this study was to develop methods for constructing a simple model describing tree mortality caused by Ips typographus L. using a minimum number of variables. We developed a model for areas spanning natural mountain forests in the Tatra National Park (Slovakia) and the Šumava National Park (Czech Republic), and in managed Czech forests located in four areas varying in environmental conditions. The model describes the time series of tree mortality dynamics caused by I.typographus using two submodels: a long-term dynamics submodel, and a short-term dynamics autoregressive distributed lag(ADL) model incorporating a two year delay and temperature variable averaged over the April-May period. The quality of fit for our models (R2 value) ranged from 0.87 to 0.91. The model was formulated to capture the average monthly temperature effect, a key weather factor. We found that for high-elevation stands located at least 1000 ma.s.l., forest damage was predominantly influenced by May t...

Research paper thumbnail of The relationship between potential solar radiation and spruce bark beetle catches in pheromone traps

Annals of Forest Research, 2012

We analysed the relationship between the amount of potential solar radiation and spruce bark beet... more We analysed the relationship between the amount of potential solar radiation and spruce bark beetle Ips typographus (L.) catches in pheromone traps in an unmanaged nature reserve in the Carpathians (middle Slovakia region), from 2006 through 2009. This relationship was analysed under outbreak conditions. The number of traps varied in different years from 70 to 92. The traps were installed in spruce-forest-dominated stands affected by a windstorm in 2004. A GPS device was used to mark the position of the pheromone traps. The potential solar radiation was calculated with GIS tools for three different time periods in each year: with entire year, for main flight season of the spruce bark beetle and the spring swarming period. The relationship between the amount of potential solar radiation and the spruce bark beetle catches was statistically significant for each year and each time period except for the spring warming in 2007, when the pheromone traps were not set up on time.

Research paper thumbnail of Host and site factors affecting tree mortality caused by the spruce bark beetle ( Ips typographus ) in mountainous conditions

Forest Ecology and Management, 2014

Abstract To better understand the initiation and severity of tree mortality caused by the spruce ... more Abstract To better understand the initiation and severity of tree mortality caused by the spruce bark beetle (Ips typographus (L.)) during an outbreak, we analysed the entire course of an outbreak from 1990 to 2000 in the Tatra Mountains (Western Carpathians, Central Europe). This time period represents the last complete bark beetle gradation in this area. We distinguished three outbreak phases: the incipient epidemic, epidemic and post-epidemic stages. The sampling unit was the forest subcompartment. We analysed a total of 315 forest subcompartments over more than 2000 ha. We investigated the influence of 11 environmental and stand variables on two processes in different phases of the outbreak: the initiation and the severity of spruce mortality. We used factor analysis, discriminant analysis, multiple linear regressions and boosted regression trees for the statistical analyses. The results showed that the roles of host and site factors in the initiation and severity of spruce mortality caused by the spruce bark beetle differed during the outbreak according to the exploitation of available host resources. The initiation of tree mortality was primarily related to host factors, and the severity of mortality was dependent on host size and insolation.

Research paper thumbnail of Factors influencing the wind–bark beetles’ disturbance system in the course of an Ips typographus outbreak in the Tatra Mountains

Forest Ecology and Management, 2014

An outbreak of spruce bark beetle (Ips typographus [L.]) in the Tatra Mountains in the Slovak Rep... more An outbreak of spruce bark beetle (Ips typographus [L.]) in the Tatra Mountains in the Slovak Republic and Poland, Central Europe, was analysed. The study area was nearly 3000 ha. The 11 year outbreak lasted from 1990 to 2000. Three outbreak phases were identified: 1990-1994 (incipient epidemic), 1995-1996 (epidemic) and 1997-2000 (post-epidemic). More than 118,000 m 3 of trees were damaged by wind and bark beetles. The analysis considered the relationship and succession of these two types of disturbances. Discrimination analysis, a multiple linear regression and boosted regression trees were used to determine the influence of 11 variables on tree mortality initiation and severity. The wind-bark beetles disturbance system was primarily influenced by stand related factors. Tree mortality initiation primarily depends on stand age and related changes in Norway spruce size and vitality. Wind caused tree mortality severity was primarily related to the tree or stand characteristics as well. The roles of host and environmental factors in the initiation and severity of tree mortality were influenced by the I. typographus outbreak phase. Stand, site and solar radiation variables were the most important factors impacting tree mortality severity caused by this disturbance system, especially in the epidemic phase. However, the severity of tree mortality caused by wind was primarily correlated with the stand characteristics. With the exception of elevation, the roles of the studied factors were similar in all gradation phases.

Research paper thumbnail of Northernmost European spruce bark beetle Ips typographus outbreak: Modelling tree mortality using remote sensing and climate data

Forest Ecology and Management, 2022

Research paper thumbnail of Effect of mature spruce forest on canopy interception in subalpine conditions during three growing seasons

Journal of Hydrology and Hydromechanics, 2021

The interception process in subalpine Norway spruce stands plays an important role in the distrib... more The interception process in subalpine Norway spruce stands plays an important role in the distribution of throughfall. The natural mountain spruce forest where our measurements of throughfall and gross precipitation were carried out, is located on the tree line at an elevation of 1,420 m a.s.l. in the Western Tatra Mountains (Slovakia, Central Europe). This paper presents an evaluation of the interception process in a natural mature spruce stand during the growing season from May to October in 2018–2020. We also analyzed the daily precipitation events within each growing season and assigned to them individual synoptic types. The amount and distribution of precipitation during the growing season plays an important role in the precipitation-interception process, which confirming the evaluation of individual synoptic situations. During the monitored growing seasons, precipitation was normal (2018), sub-normal (2019) and above-normal (2020) in comparison with long-term precipitation (19...

Research paper thumbnail of Influence of weather and day length on intra-seasonal growth of Norway spruce (Picea abies) and European beech (Fagus sylvatica) in a natural montane forest

Canadian Journal of Forest Research, 2021

Intra-seasonal growth responses of co-occurring European beech (Fagus sylvatica L.) and Norway sp... more Intra-seasonal growth responses of co-occurring European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst.) to weather variability in montane forests can provide useful information on their future growth trends. To improve growth predictions, we aimed to identify (i) the main seasonal windows during which weather variability influences tree-ring growth, (ii) species-specific differences in the response to weather fluctuations, and (iii) teleconnections to remote sites in the Western Carpathians. We monitored intra-seasonal growth dynamics based on proxies extracted growth signals detected by high-resolution dendrometers in the transition zone between the beech and spruce altitudinal belt. Over 12 consecutive seasons in the natural montane forest (1350 m a.s.l.), the main part of spruce (68% to 10 July) and beech (95% to 26 August) annual increment was under the prevailing influence of temperature. After this, precipitation pattern (regarding spruce) and day lengt...

Research paper thumbnail of Weather conditions and host characteristics drive infestations of sessile oak (Quercus petraea) trap trees by oak bark beetles (Scolytus intricatus)

Forest Ecology and Management, 2022

Research paper thumbnail of Reproductive Isolation of Ips nitidus and I. shangrila in Mountain Forests of Western China: Responses to Chiral and Achiral Candidate Pheromone Components

Journal of Chemical Ecology, 2015

Eastern Palearctic conifers are subject to frequent bark beetle outbreaks. However, neither the s... more Eastern Palearctic conifers are subject to frequent bark beetle outbreaks. However, neither the species responsible nor the semiochemicals guiding these attacks are well understood. Two high-mountain Ips species on Qinghai spruce, Picea crassifolia, I. shangrila and I. nitidus, are typical in this regard. Six synthetic candidate pheromone components that we earlier identified from hindguts of unmated males of these two Ips species were tested for field activity in Qinghai province, P. R. China. For I. nitidus, racemic ipsdienol ((±)-Id) could replace the naturally-produced blend of enantiomers containing 74 % (-)-(S)-Id (74:26 S:R), in attractive ternary or binary blends. In contrast, sympatric I. shangrila were attracted mainly to blends including Id of opposite chirality, 97 %-(+)-(R)-Id. Of the verbenols, (-)-trans-verbenol was inactive for I. nitidus or inhibitory for I. shangrila, but (-)-cis-verbenol (cV) was a key component of the pheromone in both species. Two fully factorial experiments demonstrated that (±)-Id, cV, and 2-methyl-3-buten-2-ol (MB) are components of the aggregation pheromone of I. nitidus, whereas only (+)-Id and cV are essential components of the aggregation pheromone of I. shangrila. While MB is not necessary for attraction of I. shangrila, it is an active antagonist and likely functions in species isolation. A review of the pheromone production and responses in Palearctic Ips and Pseudoips showed that cV is more common than methylbutenols, and both elicit qualitatively variable responses. Ipsdienol is the most common component with variable chirality, and is a necessary, but often not sufficient, factor for determining pheromone specificity.

Research paper thumbnail of Frontiers of protected areas versus forest exploitation: Assessing habitat network functionality in 16 case study regions globally

Ambio, 2021

Exploitation of natural forests forms expanding frontiers. Simultaneously, protected area frontie... more Exploitation of natural forests forms expanding frontiers. Simultaneously, protected area frontiers aim at maintaining functional habitat networks. To assess net effects of these frontiers, we examined 16 case study areas on five continents. We (1) mapped protected area instruments, (2) assessed their effectiveness, (3) mapped policy implementation tools, and (4) effects on protected areas originating from their surroundings. Results are given as follows: (1) conservation instruments covered 3–77%, (2) effectiveness of habitat networks depended on representativeness, habitat quality, functional connectivity, resource extraction in protected areas, time for landscape restoration, “paper parks”, “fortress conservation”, and data access, (3) regulatory policy instruments dominated over economic and informational, (4) negative matrix effects dominated over positive ones (protective forests, buffer zones, inaccessibility), which were restricted to former USSR and Costa Rica. Despite evid...

Research paper thumbnail of Drivers of Spruce Bark Beetle (Ips typographus) Infestations on Downed Trees after Severe Windthrow

Forests

Research Highlights: Bark beetles are important agents of disturbance regimes in temperate forest... more Research Highlights: Bark beetles are important agents of disturbance regimes in temperate forests, and specifically in a connected wind-bark beetle disturbance system. Large-scale windthrows trigger population growth of the European spruce bark beetle (Ips typographus L.) from endemic to epidemic levels, thereby allowing the killing of Norway spruce trees over several consecutive years. Background and Objectives: There is a lack of evidence to differentiate how outbreaks are promoted by the effects of environmental variables versus beetle preferences of trees from endemic to outbreak. However, little is known about how individual downed-tree characteristics and local conditions such as tree orientation and solar radiation affect beetle colonization of downed trees. Materials and Methods: To answer this question, we investigated the infestation rates and determined tree death categories (uprooted, broken, and stump) in wind-damaged areas in Western Tatra Mts. in Carpathians (Slovaki...

Research paper thumbnail of Influence of different forest protection strategies on spruce tree mortality during a bark beetle outbreak

Annals of Forest Science

Under an outbreak scenario in a buffer zone of a protected area, bark beetle-caused tree mortalit... more Under an outbreak scenario in a buffer zone of a protected area, bark beetle-caused tree mortality was modulated by earlier natural disturbances (wind and bark beetles), sanitary management and seasonal temperature. In buffer zones, the effects of sanitary management on tree mortality remained limited due to the migration of bark beetles from unmanaged areas.

Research paper thumbnail of Potential Solar Radiation as a Driver for Bark Beetle Infestation on a Landscape Scale

Forests

In recent decades, Norway spruce (Picea abies L. Karst.) forests of the High Tatra Mountains have... more In recent decades, Norway spruce (Picea abies L. Karst.) forests of the High Tatra Mountains have suffered unprecedented tree mortality caused by European spruce bark beetle (Ips typographus L.). Analysis of the spatiotemporal pattern of bark beetle outbreaks across the landscape in consecutive years can provide new insights into the population dynamics of tree-killing insects. A bark beetle outbreak occurred in the High Tatra Mountains after a storm damaged more than 10,000 ha of forests in 2004. We combined yearly Landsat-derived bark beetle infestation spots from 2006 to 2014 and meteorological data to identify the susceptibility of forest stands to beetle infestation. We found that digital elevation model (DEM)-derived potential radiation loads predicted beetle infestation, especially in the peak phase of beetle epidemic. Moreover, spots attacked at the beginning of our study period had higher values of received solar radiation than spots at the end of the study period, indicati...

Research paper thumbnail of Landscape-level spread of beetle infestations from windthrown- and beetle-killed trees in the non-intervention zone of the Tatra National Park, Slovakia (Central Europe)

Forest Ecology and Management

Research paper thumbnail of Hodnotenie zdravotného stavu smreka vo vzťahu k náletu podkôrneho hmyzu a k odumieraniu lesa

Táto publikácia vznikla vďaka podpore v rámci operačného programu Výskum a vývoj pre projekt: Pro... more Táto publikácia vznikla vďaka podpore v rámci operačného programu Výskum a vývoj pre projekt: Prognosticko-informačné systémy pre zvýšenie efektívnosti manažmentu lesa, ITMS 26220220109, spolufinancovaný zo zdrojov Európskeho fondu regionálneho rozvoja.

Research paper thumbnail of Population dynamics of spruce bark beetle in a nature reserve in relation to stand edges conditions

MEZEI, P., JAKUŠ, R., BLAŽENEC, M., BELÁNOVÁ, S., ŠMÍDT, J. 2011. Population dynamics of spruce b... more MEZEI, P., JAKUŠ, R., BLAŽENEC, M., BELÁNOVÁ, S., ŠMÍDT, J. 2011. Population dynamics of spruce bark beetle in a nature reserve in relation to stand edges conditions. Folia oecol., 38: 73-79.

Research paper thumbnail of Influence of different forest protection strategies on spruce tree mortality during a bark beetle outbreak

Annals of Forest Science

Under an outbreak scenario in a buffer zone of a protected area, bark beetle-caused tree mortalit... more Under an outbreak scenario in a buffer zone of a protected area, bark beetle-caused tree mortality was modulated by earlier natural disturbances (wind and bark beetles), sanitary management and seasonal temperature. In buffer zones, the effects of sanitary management on tree mortality remained limited due to the migration of bark beetles from unmanaged areas.

Research paper thumbnail of Landscape-level spread of beetle infestations from windthrown- and beetle-killed trees in the non-intervention zone of the Tatra National Park, Slovakia (Central Europe)

Forest Ecology and Management

Research paper thumbnail of Contrasting Norway spruce disturbance dynamics in managed forests and strict forest reserves in Slovakia

Forestry

Forest disturbances are intensifying globally, yet regional drivers of these dynamics remain poor... more Forest disturbances are intensifying globally, yet regional drivers of these dynamics remain poorly understood. We investigated recent disturbance intensities in Norway spruce (Picea abies L.) forests in Slovakia (Central Europe) with different management objectives in 2000–2017 based on Landsat imagery. We focused on 122 strict reserves without any management, their actively managed surroundings (500 m and 2000 m buffers), and managed production forests beyond the buffer areas. We used generalized additive mixed models to test for differences in temporal trends of disturbance intensity among these management categories. We found that disturbance intensity was increasing in all management categories during the studied period. The increase was more pronounced in the managed forests (compound annual disturbance rate 1.76% year−1) and the 2000 m buffer (2.21% year−1) than in the strict reserves (0.58% year−1). The predicted cumulative disturbance during the 18-year period was 9.9% in t...

Research paper thumbnail of Infestation Patterns of Multi-Species Coniferous Forests by Two Bark Beetle Species in Kunashir Island in the Far East

Social Science Research Network, 2022

Research paper thumbnail of Wind Damage and Temperature Effect on Tree Mortality Caused by Ips typographus L.: Phase Transition Model

Forests, 2022

The aim of this study was to develop methods for constructing a simple model describing tree mort... more The aim of this study was to develop methods for constructing a simple model describing tree mortality caused by Ips typographus L. using a minimum number of variables. We developed a model for areas spanning natural mountain forests in the Tatra National Park (Slovakia) and the Šumava National Park (Czech Republic), and in managed Czech forests located in four areas varying in environmental conditions. The model describes the time series of tree mortality dynamics caused by I.typographus using two submodels: a long-term dynamics submodel, and a short-term dynamics autoregressive distributed lag(ADL) model incorporating a two year delay and temperature variable averaged over the April-May period. The quality of fit for our models (R2 value) ranged from 0.87 to 0.91. The model was formulated to capture the average monthly temperature effect, a key weather factor. We found that for high-elevation stands located at least 1000 ma.s.l., forest damage was predominantly influenced by May t...

Research paper thumbnail of The relationship between potential solar radiation and spruce bark beetle catches in pheromone traps

Annals of Forest Research, 2012

We analysed the relationship between the amount of potential solar radiation and spruce bark beet... more We analysed the relationship between the amount of potential solar radiation and spruce bark beetle Ips typographus (L.) catches in pheromone traps in an unmanaged nature reserve in the Carpathians (middle Slovakia region), from 2006 through 2009. This relationship was analysed under outbreak conditions. The number of traps varied in different years from 70 to 92. The traps were installed in spruce-forest-dominated stands affected by a windstorm in 2004. A GPS device was used to mark the position of the pheromone traps. The potential solar radiation was calculated with GIS tools for three different time periods in each year: with entire year, for main flight season of the spruce bark beetle and the spring swarming period. The relationship between the amount of potential solar radiation and the spruce bark beetle catches was statistically significant for each year and each time period except for the spring warming in 2007, when the pheromone traps were not set up on time.

Research paper thumbnail of Host and site factors affecting tree mortality caused by the spruce bark beetle ( Ips typographus ) in mountainous conditions

Forest Ecology and Management, 2014

Abstract To better understand the initiation and severity of tree mortality caused by the spruce ... more Abstract To better understand the initiation and severity of tree mortality caused by the spruce bark beetle (Ips typographus (L.)) during an outbreak, we analysed the entire course of an outbreak from 1990 to 2000 in the Tatra Mountains (Western Carpathians, Central Europe). This time period represents the last complete bark beetle gradation in this area. We distinguished three outbreak phases: the incipient epidemic, epidemic and post-epidemic stages. The sampling unit was the forest subcompartment. We analysed a total of 315 forest subcompartments over more than 2000 ha. We investigated the influence of 11 environmental and stand variables on two processes in different phases of the outbreak: the initiation and the severity of spruce mortality. We used factor analysis, discriminant analysis, multiple linear regressions and boosted regression trees for the statistical analyses. The results showed that the roles of host and site factors in the initiation and severity of spruce mortality caused by the spruce bark beetle differed during the outbreak according to the exploitation of available host resources. The initiation of tree mortality was primarily related to host factors, and the severity of mortality was dependent on host size and insolation.

Research paper thumbnail of Factors influencing the wind–bark beetles’ disturbance system in the course of an Ips typographus outbreak in the Tatra Mountains

Forest Ecology and Management, 2014

An outbreak of spruce bark beetle (Ips typographus [L.]) in the Tatra Mountains in the Slovak Rep... more An outbreak of spruce bark beetle (Ips typographus [L.]) in the Tatra Mountains in the Slovak Republic and Poland, Central Europe, was analysed. The study area was nearly 3000 ha. The 11 year outbreak lasted from 1990 to 2000. Three outbreak phases were identified: 1990-1994 (incipient epidemic), 1995-1996 (epidemic) and 1997-2000 (post-epidemic). More than 118,000 m 3 of trees were damaged by wind and bark beetles. The analysis considered the relationship and succession of these two types of disturbances. Discrimination analysis, a multiple linear regression and boosted regression trees were used to determine the influence of 11 variables on tree mortality initiation and severity. The wind-bark beetles disturbance system was primarily influenced by stand related factors. Tree mortality initiation primarily depends on stand age and related changes in Norway spruce size and vitality. Wind caused tree mortality severity was primarily related to the tree or stand characteristics as well. The roles of host and environmental factors in the initiation and severity of tree mortality were influenced by the I. typographus outbreak phase. Stand, site and solar radiation variables were the most important factors impacting tree mortality severity caused by this disturbance system, especially in the epidemic phase. However, the severity of tree mortality caused by wind was primarily correlated with the stand characteristics. With the exception of elevation, the roles of the studied factors were similar in all gradation phases.

Research paper thumbnail of Northernmost European spruce bark beetle Ips typographus outbreak: Modelling tree mortality using remote sensing and climate data

Forest Ecology and Management, 2022

Research paper thumbnail of Effect of mature spruce forest on canopy interception in subalpine conditions during three growing seasons

Journal of Hydrology and Hydromechanics, 2021

The interception process in subalpine Norway spruce stands plays an important role in the distrib... more The interception process in subalpine Norway spruce stands plays an important role in the distribution of throughfall. The natural mountain spruce forest where our measurements of throughfall and gross precipitation were carried out, is located on the tree line at an elevation of 1,420 m a.s.l. in the Western Tatra Mountains (Slovakia, Central Europe). This paper presents an evaluation of the interception process in a natural mature spruce stand during the growing season from May to October in 2018–2020. We also analyzed the daily precipitation events within each growing season and assigned to them individual synoptic types. The amount and distribution of precipitation during the growing season plays an important role in the precipitation-interception process, which confirming the evaluation of individual synoptic situations. During the monitored growing seasons, precipitation was normal (2018), sub-normal (2019) and above-normal (2020) in comparison with long-term precipitation (19...

Research paper thumbnail of Influence of weather and day length on intra-seasonal growth of Norway spruce (Picea abies) and European beech (Fagus sylvatica) in a natural montane forest

Canadian Journal of Forest Research, 2021

Intra-seasonal growth responses of co-occurring European beech (Fagus sylvatica L.) and Norway sp... more Intra-seasonal growth responses of co-occurring European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst.) to weather variability in montane forests can provide useful information on their future growth trends. To improve growth predictions, we aimed to identify (i) the main seasonal windows during which weather variability influences tree-ring growth, (ii) species-specific differences in the response to weather fluctuations, and (iii) teleconnections to remote sites in the Western Carpathians. We monitored intra-seasonal growth dynamics based on proxies extracted growth signals detected by high-resolution dendrometers in the transition zone between the beech and spruce altitudinal belt. Over 12 consecutive seasons in the natural montane forest (1350 m a.s.l.), the main part of spruce (68% to 10 July) and beech (95% to 26 August) annual increment was under the prevailing influence of temperature. After this, precipitation pattern (regarding spruce) and day lengt...

Research paper thumbnail of Weather conditions and host characteristics drive infestations of sessile oak (Quercus petraea) trap trees by oak bark beetles (Scolytus intricatus)

Forest Ecology and Management, 2022

Research paper thumbnail of Reproductive Isolation of Ips nitidus and I. shangrila in Mountain Forests of Western China: Responses to Chiral and Achiral Candidate Pheromone Components

Journal of Chemical Ecology, 2015

Eastern Palearctic conifers are subject to frequent bark beetle outbreaks. However, neither the s... more Eastern Palearctic conifers are subject to frequent bark beetle outbreaks. However, neither the species responsible nor the semiochemicals guiding these attacks are well understood. Two high-mountain Ips species on Qinghai spruce, Picea crassifolia, I. shangrila and I. nitidus, are typical in this regard. Six synthetic candidate pheromone components that we earlier identified from hindguts of unmated males of these two Ips species were tested for field activity in Qinghai province, P. R. China. For I. nitidus, racemic ipsdienol ((±)-Id) could replace the naturally-produced blend of enantiomers containing 74 % (-)-(S)-Id (74:26 S:R), in attractive ternary or binary blends. In contrast, sympatric I. shangrila were attracted mainly to blends including Id of opposite chirality, 97 %-(+)-(R)-Id. Of the verbenols, (-)-trans-verbenol was inactive for I. nitidus or inhibitory for I. shangrila, but (-)-cis-verbenol (cV) was a key component of the pheromone in both species. Two fully factorial experiments demonstrated that (±)-Id, cV, and 2-methyl-3-buten-2-ol (MB) are components of the aggregation pheromone of I. nitidus, whereas only (+)-Id and cV are essential components of the aggregation pheromone of I. shangrila. While MB is not necessary for attraction of I. shangrila, it is an active antagonist and likely functions in species isolation. A review of the pheromone production and responses in Palearctic Ips and Pseudoips showed that cV is more common than methylbutenols, and both elicit qualitatively variable responses. Ipsdienol is the most common component with variable chirality, and is a necessary, but often not sufficient, factor for determining pheromone specificity.

Research paper thumbnail of Frontiers of protected areas versus forest exploitation: Assessing habitat network functionality in 16 case study regions globally

Ambio, 2021

Exploitation of natural forests forms expanding frontiers. Simultaneously, protected area frontie... more Exploitation of natural forests forms expanding frontiers. Simultaneously, protected area frontiers aim at maintaining functional habitat networks. To assess net effects of these frontiers, we examined 16 case study areas on five continents. We (1) mapped protected area instruments, (2) assessed their effectiveness, (3) mapped policy implementation tools, and (4) effects on protected areas originating from their surroundings. Results are given as follows: (1) conservation instruments covered 3–77%, (2) effectiveness of habitat networks depended on representativeness, habitat quality, functional connectivity, resource extraction in protected areas, time for landscape restoration, “paper parks”, “fortress conservation”, and data access, (3) regulatory policy instruments dominated over economic and informational, (4) negative matrix effects dominated over positive ones (protective forests, buffer zones, inaccessibility), which were restricted to former USSR and Costa Rica. Despite evid...

Research paper thumbnail of Drivers of Spruce Bark Beetle (Ips typographus) Infestations on Downed Trees after Severe Windthrow

Forests

Research Highlights: Bark beetles are important agents of disturbance regimes in temperate forest... more Research Highlights: Bark beetles are important agents of disturbance regimes in temperate forests, and specifically in a connected wind-bark beetle disturbance system. Large-scale windthrows trigger population growth of the European spruce bark beetle (Ips typographus L.) from endemic to epidemic levels, thereby allowing the killing of Norway spruce trees over several consecutive years. Background and Objectives: There is a lack of evidence to differentiate how outbreaks are promoted by the effects of environmental variables versus beetle preferences of trees from endemic to outbreak. However, little is known about how individual downed-tree characteristics and local conditions such as tree orientation and solar radiation affect beetle colonization of downed trees. Materials and Methods: To answer this question, we investigated the infestation rates and determined tree death categories (uprooted, broken, and stump) in wind-damaged areas in Western Tatra Mts. in Carpathians (Slovaki...

Research paper thumbnail of Influence of different forest protection strategies on spruce tree mortality during a bark beetle outbreak

Annals of Forest Science

Under an outbreak scenario in a buffer zone of a protected area, bark beetle-caused tree mortalit... more Under an outbreak scenario in a buffer zone of a protected area, bark beetle-caused tree mortality was modulated by earlier natural disturbances (wind and bark beetles), sanitary management and seasonal temperature. In buffer zones, the effects of sanitary management on tree mortality remained limited due to the migration of bark beetles from unmanaged areas.

Research paper thumbnail of Potential Solar Radiation as a Driver for Bark Beetle Infestation on a Landscape Scale

Forests

In recent decades, Norway spruce (Picea abies L. Karst.) forests of the High Tatra Mountains have... more In recent decades, Norway spruce (Picea abies L. Karst.) forests of the High Tatra Mountains have suffered unprecedented tree mortality caused by European spruce bark beetle (Ips typographus L.). Analysis of the spatiotemporal pattern of bark beetle outbreaks across the landscape in consecutive years can provide new insights into the population dynamics of tree-killing insects. A bark beetle outbreak occurred in the High Tatra Mountains after a storm damaged more than 10,000 ha of forests in 2004. We combined yearly Landsat-derived bark beetle infestation spots from 2006 to 2014 and meteorological data to identify the susceptibility of forest stands to beetle infestation. We found that digital elevation model (DEM)-derived potential radiation loads predicted beetle infestation, especially in the peak phase of beetle epidemic. Moreover, spots attacked at the beginning of our study period had higher values of received solar radiation than spots at the end of the study period, indicati...

Research paper thumbnail of Landscape-level spread of beetle infestations from windthrown- and beetle-killed trees in the non-intervention zone of the Tatra National Park, Slovakia (Central Europe)

Forest Ecology and Management

Research paper thumbnail of Hodnotenie zdravotného stavu smreka vo vzťahu k náletu podkôrneho hmyzu a k odumieraniu lesa

Táto publikácia vznikla vďaka podpore v rámci operačného programu Výskum a vývoj pre projekt: Pro... more Táto publikácia vznikla vďaka podpore v rámci operačného programu Výskum a vývoj pre projekt: Prognosticko-informačné systémy pre zvýšenie efektívnosti manažmentu lesa, ITMS 26220220109, spolufinancovaný zo zdrojov Európskeho fondu regionálneho rozvoja.

Research paper thumbnail of Population dynamics of spruce bark beetle in a nature reserve in relation to stand edges conditions

MEZEI, P., JAKUŠ, R., BLAŽENEC, M., BELÁNOVÁ, S., ŠMÍDT, J. 2011. Population dynamics of spruce b... more MEZEI, P., JAKUŠ, R., BLAŽENEC, M., BELÁNOVÁ, S., ŠMÍDT, J. 2011. Population dynamics of spruce bark beetle in a nature reserve in relation to stand edges conditions. Folia oecol., 38: 73-79.

Research paper thumbnail of Influence of different forest protection strategies on spruce tree mortality during a bark beetle outbreak

Annals of Forest Science

Under an outbreak scenario in a buffer zone of a protected area, bark beetle-caused tree mortalit... more Under an outbreak scenario in a buffer zone of a protected area, bark beetle-caused tree mortality was modulated by earlier natural disturbances (wind and bark beetles), sanitary management and seasonal temperature. In buffer zones, the effects of sanitary management on tree mortality remained limited due to the migration of bark beetles from unmanaged areas.

Research paper thumbnail of Landscape-level spread of beetle infestations from windthrown- and beetle-killed trees in the non-intervention zone of the Tatra National Park, Slovakia (Central Europe)

Forest Ecology and Management