Drivers of Spruce Bark Beetle (Ips typographus) Infestations on Downed Trees after Severe Windthrow
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 tre…
Enhancing Resilience of Boreal Forests Through Management Under Global Change: a Review
Abstract Purpose of Review Boreal forests provide a wide range of ecosystem services that are important to society. The boreal biome is experiencing the highest rates of warming on the planet and increasing demand for forest products. Here, we review how changes in climate and its associated extreme events (e.g., windstorms) are putting at risk the capacity of these forests to continue providing ecosystem services. We further analyze the role of forest management to increase forest resilience to the combined effects of climate change and extreme events. Recent Findings Enhancing forest resilience recently gained a lot of interest from theoretical perspective. Yet, it remains unclear how to …
Choosy beetles : How host trees and southern boreal forest naturalness may determine dead wood beetle communities
Wood-living beetles make up a large proportion of forest biodiversity and contribute to important ecosystem services, including decomposition. Beetle communities in managed southern boreal forests are less species rich than in natural and near-natural forest stands. In addition, many beetle species rely primarily on specific tree species. Yet, the associations between individual beetle species, forest management category, and tree species are seldom quantified, even for red-listed beetles. We compiled a beetle capture dataset from flight intercept traps placed on Norway spruce (Picea abies), oak (Quercus sp.), and Eurasian aspen (Populus tremulae) trees in 413 sites in mature managed forest…
Interventions have limited effects on the population dynamics of Ips typographus and its natural enemies in the Western Carpathians (Central Europe)
Abstract Outbreaks of the European spruce bark beetle Ips typographus kill extensive areas of Norway spruce forests in Central Europe, affecting both protected areas and neighboring commercial forests. In protected areas, uncontrolled (non-intervention) management allows natural beetle-induced tree mortality, while in commercial forests infested trees are salvage-logged in order to lower I. typographus numbers and stabilize wood production. However, the effects of active pest controls on I. typographus population are often ambiguous, and little is known about how antagonists, beetle density, or intraspecific competition help terminate I. typographus outbreaks. To answer this question, we st…
A bark beetle infestation predictive model based on satellite data in the frame of decision support system TANABBO
The European spruce bark beetle Ips typographus L. causes significant economic losses in managed coniferous forests in Central and Northern Europe. New infestations either occur in previously undisturbed forest stands (i.e., spot initiation) or depend on proximity to previous years’ infestations (i.e., spot spreading). Early identification of newly infested trees over the forested landscape limits the effective control measures. Accurate forecasting of the spread of bark beetle infestation is crucial to plan efficient sanitation felling of infested trees and prevent further propagation of beetle-induced tree mortality. We created a predictive model of subsequent year spot initiation and spo…
Functional structure of European forest beetle communities is enhanced by rare species
Biodiverse communities have been shown to sustain high levels of multifunctionality and thus a loss of species likely negatively impacts ecosystem functions. For most taxa, however, roles of individual species are poorly known. Rare species, often most likely to go extinct, may have unique traits and functional roles. Alternatively, rare species may be functionally redundant, such that their loss would not disrupt ecosystem functions. We quantified the functional role of rare species by using captures of wood-living (saproxylic) beetle species, combined with recent databases of morphological and ecological traits, from three regions in central and northern Europe. Using a rarity index based…
Building up an ecologically sustainable and socially desirable post-COVID-19 future
AbstractCOVID-19 crisis has emphasized how poorly prepared humanity is to cope with global disasters. However, this crisis also offers a unique opportunity to move towards a more sustainable and equitable future. Here, we identify the underlying environmental, social, and economic chronic causes of the COVID-19 crisis. We argue in favour of a holistic view to initiate a socio-economic transition to improve the prospects for global sustainability and human well-being. Alternative approaches to “Business-As-Usual” for guiding the transition are already available for implementation. Yet, to ensure a successful and just transition, we need to change our priorities towards environmental integrit…
Potential Solar Radiation as a Driver for Bark Beetle Infestation on a Landscape Scale
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 digi…
Reakcia dubov voči klimatickým extrémom v prechodnej zóne dubových a bukových lesov
Forest management might be threatened by declining health status of oaks in the transition zone between oak and beech forests, where drought is the most limiting factor. The aim of the presented paper is to assess the influence of selected climatic characteristics on the radial growth of oak trees with different stem diameter status in the beech-oak and oak-beech forest altitudinal zones within the forest growth area of Poľana Mt. and Zvolen Basin (Slovakia). Our results show that oaks with less favourable stem diameter position (Weisse’s middle stems) show slower radial growth, have less pronounced climatic precipitation signal and milder response to extreme climatic events. The findings p…
Interpreting wind damage risk-how multifunctional forest management impacts standing timber at risk of wind felling
AbstractLandscape multifunctionality, a widely accepted challenge for boreal forests, aims to simultaneously provide timber, non-timber ecosystem services, and shelter for biodiversity. However, multifunctionality requires the use of novel forest management regimes optimally combined over the landscape, and an increased share of sets asides. It remains unclear how this combination will shape stand vulnerability to wind disturbances and exposed timber volume. We combined forest growth simulations and multi-objective optimization to create alternative landscape level forest management scenarios. Management choices were restricted to 1) rotation forestry, 2) continuous cover forestry, and 3) a…
Sectoral policies cause incoherence in forest management and ecosystem service provisioning
Various national policies guide forest use, but often with competing policy objectives leading to divergent management paradigms. Incoherent policies may negatively impact the sustainable provision of forest ecosystem services (FES), and forest multifunctionality. There is uncertainty among policymakers about the impacts of policies on the real world. We translated the policy documents of Finland into scenarios including the quantitative demands for FES, representing: the national forest strategy (NFS), the biodiversity strategy (BDS), and the bioeconomy strategy (BES). We simulated a Finland-wide systematic sample of forest stands with alternative management regimes and climate change. Fin…
High‐resolution 3D forest structure explains ecomorphological trait variation in assemblages of saproxylic beetles
1. Climate, topography and the 3D structure of forests are major drivers affecting local species communities. However, little is known about how the specific functional traits of saproxylic (wood-living) beetles, involved in the recycling of wood, might be affected by those environmental characteristics. 2. Here, we combine ecological and morphological traits available for saproxylic beetles and airborne laser scanning (ALS) data in Bayesian trait-based joint species distribution models to study how traits drive the distributions of more than 230 species in temperate forests of Europe. 3. We found that elevation (as a proxy for temperature and precipitation) and the proportion of conifers p…
Traits mediate niches and co‐occurrences of forest beetles in ways that differ among bioclimatic regions
Aim The aim of this study was to investigate the role of traits in beetle community assembly and test for consistency in these effects among several bioclimatic regions. We asked (1) whether traits predicted species’ responses to environmental gradients (i.e. their niches), (2) whether these same traits could predict co-occurrence patterns and (3) how consistent were niches and the role of traits among study regions. Location Boreal forests in Norway and Finland, temperate forests in Germany. Taxon Wood-living (saproxylic) beetles. Methods We compiled capture records of 468 wood-living beetle species from the three regions, along with nine morphological and ecological species traits. Eight …
High boreal forest multifunctionality requires continuous cover forestry as a dominant management
Intensive extraction of forest resources lowers biodiversity and endangers the functioning of forest ecosystems. As such, alternative management regimes have emerged, aspiring to promote forest biodiversity and nature protection in managed forests. Among them, continuous cover forestry, (i.e. selective logging), has received considerable attention and is being promoted by some researchers and NGOs. Yet, the full consequences of banning clear-cuts (i.e. rotation forestry) and replacing it entirely with continuous cover forest remains uncertain. We explore how restricting forest management alternatives (either rotation forestry or continuous cover forestry) will affect landscape-scale forest …
Contrasting Norway spruce disturbance dynamics in managed forests and strict forest reserves in Slovakia
Abstract 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 man…