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... It is important to guarantee the property of biological compatibility when estimating tree biomass of the total and components for carbon accounting under global climate change. The issue was successfully considered in traditional nonlinear regression models, but not for machine learning methods. A new method for approaching the compatibility of tree biomass estimation in ANN (Artificial Neural Ne ...
Pinus koraiensis; aboveground biomass; administrative management; allometry; bark; coniferous forests; dry matter partitioning; forest ecology; leaves; model validation; models; plant development; prediction; tree and stand measurements; trees; woody plants; China
Abstract:
... Tree allometric models are crucial to accurate forest biomass assessment, but the acquisition of biomass data is one of the most important limitations in establishing biomass models. This study aims to propose an improved investigation method to quickly and practically obtain biomass data, establish species-specific allometric equations and evaluate the biomass allocation pattern for various tree ...
Pinus; Quercus; bark; fire history; forest ecology; resource allocation
Abstract:
... Pines (Pinus, with 120 species) and oaks (Quercus, with at least 400 species), the two principal forest forming genera of the Northern Hemisphere occur in fire affected landscapes over a large geographical area from 120°W to 150°E long, and from 10° to 60°N lat. We compiled studies of 116 such sites of which 75 sites had data of bark thickness. Taking a meta-analysis approach, here we have compare ...
Nothofagus pumilio; aboveground biomass; administrative management; bark; carbon; carbon dioxide fixation; cellulose; fiber content; forests; hemicellulose; lignin; long term effects; net primary productivity; nitrogen; nitrogen content; tree growth; trees; wood; Argentina
Abstract:
... Estimation of biomass and nutrient contents in tree components are essential for evaluating the impact of harvesting on carbon fixation capacity, bio-element recycling, and long-term effect on the balance that influence over net primary productivity. In many reports, fixed values were roughly considered at tree and stand level; however, the nutrient contents can vary across natural gradients (e.g. ...
Ips typographus; Picea abies; administrative management; bark; bark beetle infestations; bark beetles; canopy; case studies; data collection; forest ecology; forests; hyperspectral imagery; information sources; models; phenology; surveys; trees; Czech Republic
Abstract:
... Detection in the early phase of bark beetle infestation is a vital task for proactive management strategies, as practiced in most Central European forests, to minimize economic losses due to bark beetle infestation and to mitigate their further spreading. For this work, remote sensing methods are coming to be in great demand as an objective approach to enable monitoring bark beetle infestation eve ...
... The damage to trees that is caused by ungulate species is a natural result of their presence in ecosystems. High densities of ungulates may have a negative effect on biodiversity and the regeneration and survival of trees. The aim of this study was to identify the factors that affect the probability of the occurrence of damage in forest stands as a result of the presence of European bison (Bison b ...
... Climate change is an important risk factor for forest ecosystems through alteration of forest disturbance regimes such as bark beetle outbreaks, which in some places now are more successfully attacking host trees weakened by hotter drought events. In Mexico, ties between climate and amplified outbreaks of bark beetles have begun to be documented, although these relationships are not entirely clear ...
... The objective of our study was to determine the effect of mineral dusts alone or in combination with the entomopathogenic fungus Beauveria bassiana to control the spruce bark beetle Ips typographus. In laboratory experiments with silicon dioxide (SiO₂), diatomaceous earth (DE), Otavi-Perlit® (OP) and SilicoSec® (Ssec), 100% of all beetles died within 7 days on spruce bark at a temperature of 25 °C ...
... Natural forest disturbances are increasingly common due to ongoing climate changes but their impact on most of forest organisms is poorly studied. Here we investigate the link between spruce bark beetle Ips typographus outbreak in 2011–2017 in Białowieża Primeval Forest (Poland) and activity of a forest bat of conservation concern: the western barbastelle Barbastella barbastellus. Bats were survey ...
Ips typographus; Picea abies; administrative management; air; bark; bark beetle infestations; edge effects; field experimentation; forests; microclimate; monoterpenoids; olfactometry; phloem; sap flow; soil water potential; spring; volatile organic compounds; Central European region; Norway
Abstract:
... Mass outbreaks of the European spruce bark beetle, Ips typographus, have caused devastating damage to Norway spruce-dominated forests in Central Europe. Biotic and abiotic natural disturbances as well as logging activities promote the fragmentation of forest stands, further increasing their susceptibility to damaging events. The creation of forest edges abruptly alters microclimatic conditions, su ...
Laurent Larrieu; Benoit Courbaud; Christophe Drénou; Michel Goulard; Rita Bütler; Daniel Kozák; Daniel Kraus; Frank Krumm; Thibault Lachat; Jörg Müller; Yoan Paillet; Andreas Schuck; Jonas Stillhard; Miroslav Svoboda; Kris Vandekerkhove
administrative management; altitude; bark; biodiversity conservation; databases; forest ecology; forest management; phyllotaxy; physiological state; prediction; tree and stand measurements; trees
Abstract:
... Tree-related microhabitats (TreMs) have been identified as key features for forest-dwelling taxa and are often employed as measures for biodiversity conservation in integrative forest management. However, managing forests to ensure an uninterrupted resource supply for TreM-dwelling taxa is challenging since TreMs are structures with a limited availability, some of which are triggered by stochastic ...
administrative management; bark; biomass; combustion; drought; fire intensity; fire severity; forest ecology; forests; heat; mortality; mountains; remote sensing; streams; tree mortality; wind speed
Abstract:
... Large, severe wildfires continue to burn in frequent-fire adapted forests but the mechanisms that contribute to them and their predictability are important questions. Using a combination of ground based and remotely sensed data we analyzed the behavior and patterns of the 2020 Creek Fire where drought and bark beetles had previously created substantial levels of tree mortality in the southern Sier ...
Angophora; Corymbia; Eucalyptus; administrative management; bark; basins; canopy; climate change; drought; ecosystems; fire damage; fire frequency; fire regime; fire resistance; forest ecology; forests; mortality; risk; species diversity; tree mortality
Abstract:
... Increases in tree mortality linked to drought and fires have been reported across a range of forests globally over the last few decades. Forests that resprout epicormically/aerially should be the most resistant and resilient to changes in fire regime, yet they may be at risk of increased mortality, demographic shifts and changes to species composition due to the compounding effects of drought and ...
bark; bark beetles; decision making; drought; forest ecology; forest management; frozen soils; ice; risk; root rot; snow; snowpack; temperature; trees; wildfires; wind damage; Central European region
Abstract:
... It is expected that European Boreal and Temperate forests will be greatly affected by climate change, causing natural disturbances to increase in frequency and severity. To detangle how, through forest management, we can make forests less vulnerable to the impact of natural disturbances, we need to include the risks of such disturbances in our decision-making tools. The present review investigates ...
administrative management; bark; data collection; drought; fire suppression; forest ecology; forests; stand density; tree growth; trees; wildfires; Western United States
Abstract:
... With the increasing frequency and severity of altered disturbance regimes in dry, western U.S. forests, treatments promoting resilience have become a management objective but have been difficult to define or operationalize. Many reconstruction studies of these forests when they had active fire regimes have documented very low tree densities before the onset of fire suppression. Building on ecologi ...
Dendroctonus ponderosae; Pinus contorta var. latifolia; administrative management; bark; canopy; carbon; forest ecology; herbivores; host preferences; nitrogen; phloem; risk; tree mortality; trees
Abstract:
... Tree size often predicts the occurrence of bark beetles that breed in the inner bark (phloem) of trees. A notable example is mountain pine beetle, Dendroctonus ponderosae, which primarily kills large, old trees during outbreaks. The tree mortality pattern is often attributed to increasing phloem thickness with tree size, although tree size-dependent defences may also be important. Age effects may ...
administrative management; bark; fire resistance; forest ecology; forests; hardwood; models; prediction; regression analysis; tree mortality; trees; Southeastern United States
Abstract:
... Tree bark, as the outermost protective layer of tree stems, is an important indicator to evaluate the fire resistance properties of trees and to assess the tree mortality induced by fire. Despite its importance, many existing bark thickness models were not primarily developed for predicting bark thickness directly, i.e. with bark thickness as a response variable, and most past studies were focused ...
... Bark beetles can cause epidemic outbreaks and kill millions of cubic meters of economical and ecologically important forests around the world. It is well known what attracts and what repels different species of bark beetle, and these chemical cues can be used to protect trees and catch the beetles without using pesticides. Applying this knowledge, we investigated the use of push–pull strategies wi ...
Cervus nippon; Picea abies; Pinus sylvestris; administrative management; afforestation; bark; climate change; coniferous forests; death; deer; fungi; models; temperature; tree and stand measurements; trees; wood quality; Czech Republic
Abstract:
... Bark stripping damage reduces timber quality due to fungal infection and structural defects. Weakened stems may break and induce the death of trees, which strongly affects forest stability. Some tree species, such as Norway spruce (Picea abies [L.] Karst.), are highly susceptible to bark stripping, but Scots pine (Pinus sylvestris L.) has been studied to a lesser extent. The objective of this stud ...
Quercus petraea; Scolytus intricatus; administrative management; bark; bark beetles; equations; forest ecology; occupations; phenology; population growth; temperate forests; temperature; univoltine habit; water stress; Central European region; Slovakia
Abstract:
... The European oak bark beetle (Scolytus intricatus) has the potential to impact forest structures through its selection of certain trees. We investigated potential S. intricatus colonisation densities by setting up 150 trap trees and analysing them in 5-metre sections during a three-year period from 2014 to 2016 in a temperate forest in Slovakia, Central Europe. Understanding the population dynamic ...
Apocynaceae; Bayesian theory; administrative management; allometry; bark; forest ecology; forests; human population; mechanistic models; savannas; tree growth; tree height; trees
Abstract:
... Theoretical models of allometric scaling provide an important framework for understanding and predicting how and why the morphology and function of organisms vary with scale. However, the predictions of ‘universal’ scaling models for vascular plants do not consider different environments and disturbance types which can reduce the predictive power of these models. One important source of disturbanc ...
Abies lasiocarpa; Dendroctonus rufipennis; Picea engelmannii; Pinus contorta; administrative management; bark; bark beetles; chronosequences; climatic factors; drought; fire suppression; forest health; forest litter; forest regeneration; seedlings; species diversity; stand structure; tree mortality; trees; wildfires; Colorado; Wyoming
Abstract:
... Due to the shifting global climate, the frequency and severity of disturbances are increasing, inevitably causing an increase in disturbances overlapping in time and space. Bark beetle epidemics and wildfires have historically shaped the disturbance regimes of Western North American forests. Their interactive effects on stand dynamics and recovery are inadequately studied in Picea engelmannii (Eng ...
Cervus elaphus; Populus nigra; administrative management; bark; coppicing; demonstration farms; forage; forest ecology; genotype; hybrids; progeny; ungulates; wildlife; Central European region; Czech Republic
Abstract:
... Browsing of poplar clones by wild ungulates is a widespread problem in short rotation coppice (SRC) plantations in Central Europe. We investigated the influence of poplar genotype on ungulate browsing intensity, identified the most browsing-resistant poplar clone and explored its repellent potential. Inspection of 11 poplar clones at 7 unfenced SRC plantations in the Czech Republic revealed the mo ...
... The mountain pine beetle (Dendroctonus ponderosae Hopkins) is a bark beetle that is native to pine forests of western North America and the Black Hills of South Dakota. Recent eastward range expansion into stands of jack pine (Pinus banksiana) and associated hybrids with lodgepole pine (Pinus contorta) in western Canada has created concern that the insect will continue moving eastward. In the Grea ...
Pseudotsuga menziesii; Sequoia sempervirens; aboveground biomass; administrative management; allometry; bark; conifers; decline; dendrochronology; ecosystems; forest ecology; heartwood; leaf mass; longevity; secondary forests; stand development; time series analysis; trees; wood; North America
Abstract:
... The tallest conifers—Picea sitchensis, Pseudotsuga menziesii, Sequoia sempervirens, Sequoiadendron giganteum—are widely distributed in western North America, forming forests > 90 m tall with aboveground biomass ≥ 2000 Mg ha⁻¹. Here we combine intensive measurements of 169 trees with dendrochronology and allometry to examine tree and stand development. The species investing least in bark protection ...
Hylobius abietis; Picea abies; administrative management; bark; carene; chemical defenses; cineole; conifers; forest ecology; limonene; methyl jasmonate; pesticides; plant age
Abstract:
... Nursery-grown Norway spruce Picea abies seedlings are often heavily attacked by the pine weevil Hylobius abietis on clear-cuts the first years after planting. Because the seedlings are not resource-limited during the growing phase in the nursery they are expected to invest less in defence than naturally regenerated seedlings already present on the clear-cuts. The latter have had to cope with vario ...
... Natural disturbances are major drivers of forest dynamics. However, in the current context of anthropogenic global warming, shifts in disturbance regimes are expected. Natural disturbances usually leave biological or structural legacies which are important for early-successional species. Nevertheless, these legacies are usually eliminated by forest managers through salvage logging. Here, we invest ...
Ips typographus; Picea abies; administrative management; bark; bark beetles; drought; ecological resilience; ecosystems; forest ecology; forest management; forests; income; natural resources conservation; people; prices; quality of life; social welfare; temperature; time series analysis; transportation; wind; wood; Czech Republic; Eurasia
Abstract:
... Outbreaks of tree-killing insects are intensifying globally, affecting economies, human well-being, and driving ecosystem transitions. The Czech Republic has recently become Europe’s epicenter of the outbreak of spruce bark beetle Ips typographus, the most aggressive species in Eurasia. We investigated a countrywide outbreak dynamic during the period 2003–2019, with a special focus on the period 2 ...
arboriculture; bark; brooms; chronic diseases; environmental exposure; forest ecology; humans; microhabitats; pathogens; prediction; public safety; timber production; tree age; tree growth; trees; wood
Abstract:
... Many tree-dwelling species inhabit microhabitats that develop slowly in diseased or injured trees. Conservation planning would benefit from explicit knowledge of these processes, notably for resolving conflicts with timber production, arboricultural or public safety goals. We reviewed published rates of development of five selected common tree microhabitats and the factors affecting those rates in ...
Myotis septentrionalis; administrative management; bark; canopy; females; habitats; home range; landscapes; males; mortality; pregnancy; probability; radio frequency identification; summer; topography; trees; vegetation; white-nose syndrome; Georgia
Abstract:
... Mortality from white-nose syndrome has made management and recovery of the northern long-eared bat (Myotis septentrionalis) a priority. Ensuring availability of diurnal summer roosts, where gestation and rearing of young occurs, is a critical component of successful recovery. However, observed variation in roost selection across the species’ range makes extrapolating data across physiographic regi ...
Jackson P. Audley; Christopher J. Fettig; A. Steven Munson; Justin B. Runyon; Leif A. Mortenson; Brytten E. Steed; Kenneth E. Gibson; Carl L. Jørgensen; Stephen R. McKelvey; Joel D. McMillin; Jose F. Negrón
... Snags (standing dead trees) are important components of forest ecosystems that, among other benefits, provide critical habitat for many species of wildlife, but also represent important safety concerns to firefighters, forest workers, and the public. We identified factors that influence the fall rates of lodgepole pines, Pinus contorta Dougl. ex Loud., killed by bark beetles during a severe region ...
Eucalyptus marginata; administrative management; allometry; bark; fertilizer application; forest ecology; fuelwood; phosphorus fertilizers; recreation; regrowth; stand basal area; stand density; timber production; tree and stand measurements; tree height; trees; watersheds; wildlife habitats; Western Australia
Abstract:
... Jarrah (Eucalyptus marginata) forest is one of the most widespread native forest types of south west Western Australia (SWWA) and provides timber, firewood, wildlife habitat, water production, catchment protection and recreation. To inform management aimed at optimizing these values, a thinning trial in even aged regrowth forest was commenced in 1965. A second thinning and N and P fertilizer treat ...
... Impacts of forest management practices on soil carbon (C) and nitrogen (N) dynamics remain under debate due to complex interactions between belowground biogeochemical processes. To optimize practices that minimize soil C and N losses, we investigated the effects of management practices on soil C and N fluxes, including the leaching of dissolved organic C (DOC) and N, by comparing clearcutting, ste ...
Jamie E. Burton; Lauren T. Bennett; Sabine Kasel; Craig R. Nitschke; Mihai A. Tanase; Thomas A. Fairman; Linda Parker; Melissa Fedrigo; Cristina Aponte
Eucalyptus; administrative management; atmospheric precipitation; bark; biomass; canopy; carbon; climate change; coarse woody debris; drought; fauna; fire history; flora; heartwood; nitrogen content; refuge habitats; regression analysis; species diversity; tree mortality; trees; wildfires; wood density; Australia
Abstract:
... Dead wood, including dead standing trees (DST) and coarse woody debris (CWD), is a critical component of forest ecosystems that provides habitat and refugia for fauna, flora, and microbial communities and plays a key role in carbon and nutrient cycling. However, few studies have modelled the long-term dynamics of dead wood, limiting our ability to predict how the abundance and composition of dead ...
... Recent, widespread tree mortality in the western U.S. resulting from changes in climate, pathogens, insect activity, and forest management practices has led to concerns for many ecologically and culturally important species. Within conifers, resin-based defenses have long been recognized as a primary defense mechanism against a variety of insects and pathogens. Oleoresin produced by trees contain ...
... The fungus Elytroderma deformans causes a serious needle disease of pines in western North America and is considered the most important needle disease of ponderosa pine in Montana. While important, there has been limited evaluation of pre-commercial thinning or other treatments on disease incidence. Our study assessed the efficacy of various silvicultural treatments to reduce impacts from Elytrode ...
Jari Miina; Rainer Peltola; Pyry Veteli; Riikka Linnakoski; Marta Cortina Escribano; Juho Haveri-Heikkilä; Pirjo Mattila; Pertti Marnila; Juha-Matti Pihlava; Jarkko Hellström; Tytti Sarjala; Niko Silvan; Mikko Kurttila; Henri Vanhanen
Betula pendula; Inonotus obliquus; Russia; active ingredients; administrative management; bark; forest ecology; forests; fungi; health services; income; mineral soils; probability; soil texture; stand basal area; tree and stand measurements; trees; virulent strains; Finland
Abstract:
... Inonotus obliquus is a pathogenic fungus––known as chaga in Asia and Russia and pakuri in Finland––that grows on broadleaves. Its sterile conks are used as an active ingredient in traditional healthcare products. Due to the higher value of pakuri than the tree it grows on, the cultivation of I. obliquus on living trees is expected to generate new and increased income opportunities for forest owner ...
Abies lasiocarpa; Dendroctonus; Picea engelmannii; Pinus contorta var. latifolia; administrative management; bark; bark beetle infestations; carbon; dead wood; die-off; ecosystems; forest health; medicine; mineral soils; mineralization; national forests; nitrogen; plant litter; reforestation; soil carbon; soil water; stain fungi; total nitrogen; trees; watersheds; xylem; Wyoming
Abstract:
... Between years 2007 and 2013, an outbreak of pine- and spruce-bark beetles (Dendroctonus spp.) has decimated coniferous forests of the northwestern United States. Beetles introduced blue stain fungus to the tree xylem that caused blockage and discontinuation of plant water conductance. One of the immediate disease symptoms was premature and immediate drop-off of all needles rich in nitrogen (N). So ...
... Populus hybrids are increasingly planted in multifunctional bioenergy buffers bordering crop fields. However, such small agroforestry systems are vulnerable to damage caused by overabundant deer populations. We measured after 8 years the effects of white-tailed deer (Odocoileus virginianus), genotype and planting stock type on tree growth and ecosystem services provision (biomass production; energ ...
Ips typographus; Picea abies; bark; bark beetle infestations; bark beetles; decision making; dieback; dominant species; forest ecology; forest trees; forests; mortality; national parks; stand age; tree mortality
Abstract:
... Dealing with tree mortality caused by forest pests is one of the most demanding challenges in forest protection and management. The current spruce bark beetle infestation in the Polish part of the Białowieża Forest (BF), which started in 2012, is considered the largest in history and has nearly eliminated Norway spruce (Picea abies (L.) Karst) as a major forest tree species there. This research an ...
... Restoration of fire-prone forests is a common practice intended to increase resilience to wildfire, drought, and bark beetles. However, the long-term effects of restoration treatments on understory species, particularly non-native species, are poorly understood. We investigated long-term (23 years) effects of restoration treatments on native and non-native understory vegetation at the Lick Creek D ...
... While a recent study showed that significant amounts of the nitrogen (N) requirements of young Eucalyptus trees can be provided by nitrogen-fixing trees (NFTs) in mixed-species plantations through short-term belowground N transfer, the consequences of soil fertility on this facilitation process remain unknown. We assessed the effect of fertilization on the percentage of N derived from transfer (%N ...
... Bark beetles are keystone species that can alter the structure and function of forested ecosystems, yet the mechanisms underlying host selection and successful colonization remain poorly understood for most species. Comparison of closely related tree species that vary in their susceptibility to bark beetles could provide insights into such mechanisms. Here, we compare physical and chemical charact ...
... This study investigates the long-term effects of vegetation management on nutrient concentration of various tissues and ecosystem components of 16 to 18 year-old Douglas-fir (DF), western hemlock (WH), western redcedar (WRC), and grand fir (GF) stands growing in Oregon’s central Coast Range (CR) and DF and WRC growing in Oregon’s Cascade mountain foothills (CF) under two contrasting vegetation man ...
Ips sexdentatus; Pinus sylvestris; administrative management; bark; fire resistance; forest ecology; life history; mortality; prescribed burning; probability; tree damage; trees
Abstract:
... After fire, bark beetles pose a significant threat to trees. Resin duct characteristics in trees can increase resistance to bark beetles. However, little is known about how intra- and interspecific variations in resin ducts due to tree characteristics, fire-caused tree injury and life history traits contribute to resistance. In fall 2013, a mixed-stand of Pinus sylvestris and P. nigra was underbur ...
Dendroctonus ponderosae; Ips typographus; applied research; bark; bark beetles; climate; climate change; databases; ecosystems; forest ecology; forests; laws and regulations; population growth; risk reduction; Europe; North America
Abstract:
... Tree-killing bark beetles are globally the most destructive forest pests and their impacts have increased in recent decades. Such an increase has been consistently reported from Europe and North America, and it is, with high confidence, driven by climate change. We investigated how the scientific community in both continents responded to this situation by conducting a comprehensive search of the S ...
... In 2018, up to 4 million m³ Norway spruce was killed by the spruce bark beetle Ips typographus in Sweden. The event was unique for Sweden, in terms of both affected volume and the fact that it was triggered by severe drought stress, not by ample availability of relatively defenseless storm-felled trees. The outbreak continued in 2019 and 2020, each year with twice as many trees killed as in 2018. ...
... Quantifying forest carbon (C) and nitrogen (N) turnover rates requires better understanding of the mechanisms of decomposition of coarse woody debris (CWD). We examined the dynamics of bulk density, C, N, cellulose and lignin in downed logs, taking into account initial interspecific trait differences in bark and wood, in a 66-year-long decomposition chronosequence in an old-growth mixed boreal for ...
DNA barcoding; Pinus yunnanensis; administrative management; bark; bark beetles; community structure; conifers; dead wood; dieback; environmental impact; forestry; insect communities; issues and policy; keystone species; species diversity; trees; China
Abstract:
... China has recently announced a reform of forestry policy, with a major goal being to transform from plantation to heterogeneous forests, which have higher resistance to pests and disease and house more biodiversity. One driver of reform is increased intensity and frequency of pest-induced tree-dieback events. To inform management, we ask what effects these events have on insect biodiversity in Pin ...
... Forest residue left on the ground following harvesting (i.e., “slash”) plays an important role in moderating the physical and chemical environment of the soil for future forest growth. Leaving too little slash can leave the soil exposed to extreme fluctuations in soil conditions and fewer nutrients that may hinder future forest growth, while leaving too much slash makes it difficult for new trees ...