Search

Methane is a powerful greenhouse gas, more potent than carbon dioxide, and emitted from a variety of natural sources including wetlands, permafrost, mammalian guts and termites. As increases in global temperatures continue to break records, quantifying the magnitudes of key methane sources has never been more pertinent. Over the last 40 years, the contribution of termites to the global methane budget has been subject to much debate. The most recent estimates of termite emissions range between 9 and 15 Tg CH4 year-1, approximately 4% of emissions from natural sources (excluding wetlands). However, we argue that the current approach for estimating termite contributions to the global methane budget is flawed. Key parameters, namely termite methane emissions from soil, deadwood, living tree stems, epigeal mounds and arboreal nests, are largely ignored in global estimates. This omission occurs because data are lacking and research objectives, crucially, neglect variation in termite ecology. Furthermore, inconsistencies in data collection methods prohibit the pooling of data required to compute global estimates. Here, we summarise the advances made over the last 40 years and illustrate how different aspects of termite ecology can influence the termite contribution to global methane emissions. Additionally, we highlight technological advances that may help researchers investigate termite methane emissions on a larger scale. Finally, we consider dynamic feedback mechanisms of climate warming and land-use change on termite methane emissions. We conclude that ultimately the global contribution of termites to atmospheric methane remains unknown and thus present an alternative framework for estimating their emissions. To significantly improve estimates, we outline outstanding questions to guide future research efforts.

Soil fungi play an essential role in the fungal colonization of deadwood, with consequences for multiple ecosystem functions such as wood decomposition. Nutrient deposition can substantially affect fungal activity, but it is unclear how external nutrient inputs and host plant nutrient content interact to influence soil fungal colonization of deadwood. To advance understanding of fungal dynamics during deadwood decomposition, we conducted a field experiment with eight tree species (four angiosperms and four gymnosperms) under four nutrient additions (no nutrient addition, nitrogen (N)‐addition, phosphorus (P)‐addition and combined N‐ and P‐addition), to investigate fungal colonization and communities in different host plant clades (angiosperms and gymnosperms) over 3 years. The study revealed that host plant clade and nutrient availability interact significantly, which strongly influenced soil fungal colonization of deadwood. The percentage of shared fungi (present in both soil and deadwood) was higher in angiosperms (38.1%–47.3%) than in gymnosperms (26.5%–36.5%). Saprotrophs were the dominant functional group in the shared fungal community, with symbiotrophs as the next most abundant group, and the dominant fungal taxa were mainly K‐strategists, which were more abundant in gymnosperms than in angiosperms. Notably, there was a stronger connection between soil fungi and deadwood fungi in gymnosperms compared to angiosperms, which was likely related to the importance of K‐strategist fungi for decomposing wood with low nutrient content. Overall, the shared fungal community in angiosperms was more sensitive to nutrient addition than in gymnosperms, resulting in greater changes to fungal taxa and functional groups. In angiosperm wood, N‐addition significantly increased α‐diversity but decreased β‐diversity of the shared fungal community, indicating N‐limitation. In gymnosperm wood, P‐addition significantly reduced both α‐diversity and β‐diversity of the shared fungal community, indicating P‐limitation. Synthesis. Our study demonstrates the divergent effect of nutrient addition on fungal colonization in angiosperms versus gymnosperms. Considering interactions between inherent plant traits and exogenous nutrient availabilities thus provides a more comprehensive understanding of the association between soil fungi and deadwood fungi during wood decomposition. [ABSTRACT FROM AUTHOR]

Deadwood, a vital component of forest ecosystems, constitutes a quintessential carbon reservoir that must be disclosed under the United Nations Framework Convention on Climate Change. This reservoir, comprising fallen logs, snags, and stumps, markedly affects carbon dynamics over decades. In this study, deadwood carbon stocks were quantified using data from 2674 sites in Japan surveyed between 2011 and 2015 via the National Forest Soil Carbon Inventory, and the deadwood carbon attributes in the country were explored. Deadwood were surveyed using the line intersect method for fallen logs and the belt transect method for stumps and snags. In Japan, the deadwood carbon stock (measured in t-C/ha) was quantified at 7.5 ± 9.74 (mean ± SD), with fallen logs at 3.26 ± 4.43, stumps at 2.45 ± 5.69, and snags at 1.80 ± 5.27, with significant differences detected among these stocks (p <.001). Considering deadwood carbon accumulation in Japan, planted forests exhibited a significantly larger (p <.001) deadwood carbon stock than natural forests. Moreover, planted forests exhibited a higher proportion of fallen logs than snags and stumps, indicating the effects associated with logs left on forest floors after thinning. Based on these findings, deadwood carbon stocks have the potential to bolster the validation and refinement of computational models used in carbon accounting. [ABSTRACT FROM AUTHOR]

Community structure and ecosystem function may be driven by the size or the energy within a given habitat, but these metrics (space and energy) are difficult to separate, especially in systems where the habitat itself is also food, such as detritus. Only a handful of studies have attempted to isolate potential mechanisms experimentally, which has left a notable knowledge gap in understanding the drivers of community structure and function. Here, we tested whether fine woody debris (FWD) affects leaf litter communities primarily as a source of space or energy. We used a crossed factor design to isolate the effects of FWD as space and energy, with four treatments: (1) no FWD, (2) only energy‐providing FWD (sawdust), (3) only space‐providing synthetic wood debris, and (4) a combination of both space and energy. We hypothesized that the highest levels of diversity, carnivore:detritivore ratio, and decomposition rate would occur on plots supplied with sawdust (representing energy), synthetic woody debris (representing space), or a combination of both, depending on the relative significance of FWD as a source of either energy or space. After 7 months, FWD as a source of energy but not space led to decreased decomposer abundance and richness. Conversely, increased proportion of carnivores and labile substrate decomposition was primarily driven by FWD as a source of space. However, the fastest decomposition of more recalcitrant substrates required both space and energy (additive), and the synergy of space and energy supported the greatest proportion of carnivores. These results suggest that the presence of FWD in forest ecosystems supports increased diversity and decomposition through a synergistic interaction of space and energy and the maintenance of deadwood like FWD in forest ecosystems can thus significantly contribute to forest ecosystem function. [ABSTRACT FROM AUTHOR]

Deadwood represents a significant carbon pool and unique biodiversity reservoir in forests and savannas but has been largely overlooked until recently. Storage and release of carbon from deadwood is controlled by interacting decomposition drivers including biotic consumers (animals and microbes) and abiotic factors (water, fire, sunlight, and freeze–thaw). Although previous research has focused mainly on forests, we synthesize deadwood studies across diverse ecosystems with woody vegetation. As changing climates and land-use practices alter the landscape, we expect accelerating but variable rates of inputs and outputs from deadwood pools. Currently, Earth system models implicitly represent only microbial consumers as drivers of wood decomposition; we show that many other factors influence deadwood pools. Forest management practices increasingly recognize deadwood as an important contributor to forest dynamics, biodiversity, and carbon budgets. Together, emerging knowledge from modeling and management suggests a growing need for additional research on deadwood contributions to carbon storage and greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Temperate forest soils are considered significant methane (CH4) sinks, but other methane sources and sinks within these forests, such as trees, litter, deadwood, and the production of volatile organic compounds are not well understood. Improved understanding of all CH4 fluxes in temperate forests could help mitigate CH4 emissions from other sources and improve the accuracy of global greenhouse gas budgets. This review highlights the characteristics of temperate forests that influence CH4 flux and assesses the current understanding of the CH4 cycle in temperate forests, with a focus on those managed for specific purposes. Methane fluxes from trees, litter, deadwood, and soil, as well as the interaction of canopy-released volatile organic compounds on atmospheric methane chemistry are quantified, the processes involved and factors (biological, climatic, management) affecting the magnitude and variance of these fluxes are discussed. Temperate forests are unique in that they are extremely variable due to strong seasonality and significant human intervention. These features control CH4 flux and need to be considered in CH4 budgets. The literature confirmed that temperate planted forest soils are a significant CH4 sink, but tree stems are a small CH4 source. CH4 fluxes from foliage and deadwood vary, and litter fluxes are negligible. The production of volatile organic compounds could increase CH4's lifetime in the atmosphere, but current in-forest measurements are insufficient to determine the magnitude of any effect. For all sources and sinks more research is required into the mechanisms and microbial community driving CH4 fluxes. The variability in CH4 fluxes within each component of the forest, is also not well understood and has led to overestimation of CH4 fluxes when scaling up measurements to a forest or global scale. A roadmap for sampling and scaling is required to ensure that all CH4 sinks and sources within temperate forests are accurately accounted for and able to be included in CH4 budgets and models to ensure accurate estimates of the contribution of temperate planted forests to the global CH4 cycle. [ABSTRACT FROM AUTHOR]

Nanopore raw read accuracy has improved to over 99%, making it a potential tool for metabarcoding. For broad adoption, guidelines on quality filtering are needed to ensure reliable taxonomic unit recovery. This study aims to provide those guidelines for a fungal metabarcoding context and to apply them to a case study of ectomycorrhizae in the decaying bark of Fagus sylvatica. We introduce the eNano pipeline to test two standard metabarcoding approaches: (1) Reference-based mapping leveraging UNITE's species hypothesis system (SH approach); (2) Constructing 98% OTUs (OTU approach). Our results demonstrate that both approaches are effective with Nanopore data. When using a reference database, we recommend strict mapping criteria rather than Phred-based filtering. Leveraging the SH-system further enhances reproducibility and facilitates cross-study communication. For the 98% OTUs, filtering reads at ≥Q25 is recommended. Our case study reveals that the decay gradient is a primary determinant of community composition and that specific mycorrhizal fungi colonize decaying bark. Complementing our metabarcoding results with root tip morphotypification, we identify Laccaria amethystina and Tomentella sublilacina as key ectomycorrhizae of saplings on decaying logs. These findings demonstrate that Nanopore sequencing can provide valuable ecological insights and support its broader use in fungal metabarcoding as read quality continues to improve. [ABSTRACT FROM AUTHOR]

Effective forest management is essential for mitigating climate change effects. This is why understanding forest growth dynamics is critical for its sustainable management. Thus, characterizing forest plot deadwood levels is vital for understanding forest dynamics, and for assessments of biomass, carbon stock, and biodiversity. For the first time, this study used the leaf area index (LAI) and L-moments to characterize and model forest plot deadwood levels in the Bavarian Forest National Park from airborne laser scanning (ALS) data. This study proposes methods that can be tested for forests, especially those in temperate climates with frequent cloud coverage and limited access. The proposed method is practically significant for effective planning and management of forest resources. First, plot decay levels were characterized based on their canopy leaf area density (LAD). Then, the deadwood levels were modeled to assess the relationships between the vegetation area index (VAI), gap fraction (GF), and the third L-moment ratio (T3). Finally, we tested the rule-based methods for classifying plot decay levels based on their biophysical structures. Our results per the LAD vertical profiles clearly showed the declining levels of decay from Level 1 to 5. Our findings from the models indicate that at a 95% confidence interval, 96% of the variation in GF was explained by the VAI with a significant negative association (VAIslope = −0.047; R2 = 0.96; (p < 0.001)), while the VAI explained 92% of the variation in T3 with a significant negative association (VAIslope = −0.50; R2 = 0.92; (p < 0.001)). Testing the rule-based methods, we found that the first rule (Lcv = 0.5) classified Levels 1 and 2 at (Lcv < 0.5) against Levels 3 to 5 at (Lcv > 0.5). However, the second rule (Lskew = 0) classified Level 1 (healthy plots) as closed canopy areas (Lskew < 0) against Levels 2 to 5 (deadwood) as open canopy areas (Lskew > 0). This approach is simple and more convenient for forest managers to exploit for mapping large forest gap areas for planning and managing forest resources for improved and effective forest management. [ABSTRACT FROM AUTHOR]

Background and objectives: Forests are one of the most significant sources of species diversity in the biosphere, playing a crucial role in protecting endangered species. With a total of 115 indigenous plant species, Hyrcanian forests are considered one of the most valuable ecosystems in Iran and the world. Deadwood is one of the significant structural characteristics of these natural forests. Deadwood, as habitat trees, plays an essential role in maintaining biodiversity. Saproxylic species are invertebrates that depend on rotting wood, deadwood (standing or fallen), fungi, and other living organisms during part of their life cycle. Therefore, this study investigates and analyzes the need to replace the proposed word خشک دارزی instead of "saproxylic." Methodology: The method in this study involved a review of previous studies and the authors' research related to the comprehensive plan of saproxylic species diversity in northern Iran. Based on this, the study investigates and evaluates the most important reasons for using the Persian word خشک دارزی instead of "saproxylic" in seven different cases. These include a specialized review of the word "saproxylic," examining the distinction between obligatory and optional users of deadwood, estimating species related to deadwood, analyzing the variables affecting the abundance of saproxylic individuals, the relationship between the loss of biodiversity of Saproxylic species and the absence of deadwood, forest plantations and saproxylic individuals, and comparing the word "خشک دارزی with other similar words. Results: The specialized examination of the word "saproxylic" showed that this term forms the basis of biodiversity assessment in deadwood and describes insects living in decaying wood. Saproxylic organisms (hereafter: خشک دارزی ) directly and indirectly use deadwood as a source of energy or habitat. Twenty to twenty-five percent of the insects living in the forest are species related to deadwood. The results of examining the variables affecting the abundance of Saproxylic individuals showed that deadwood volume, the degree of deadwood decay, and the volume of living trees had significant effects on the frequency of Saproxylic individuals. Various studies also showed the relationship between the loss of biodiversity of Saproxylic individuals and the absence of deadwood, with traps (window and pit) always installed where deadwood is present. On the other hand, although plantations for wood production are one of the most important sources of wood on a wide scale, there is no sign of deadwood and, consequently, no presence of saproxylic individuals in these areas compared to natural forests. While the meaning of deadwood is a dried tree, in nature, deadwood is not always a completely dead tree. In many cases, only part of the trunk or crown of the tree is dead, while other parts are healthy. This term is known to all experts in forest ecology as referring to any part of a completely dead tree, aligning with the term deadwood. Conclusion: Therefore, the word "خشک دارزی instead of "Saproxylic" can effectively describe this category of species in the Persian language. Finally, the necessity of replacing non-Persian words with suitable Persian words and equating these words in scientific research writings, while preserving their expressive meaning in Persian, can be a positive step towards specialized vocabulary. [ABSTRACT FROM AUTHOR]

Deadwood, a vital component of forest ecosystems, constitutes a quintessential carbon reservoir that must be disclosed under the United Nations Framework Convention on Climate Change. This reservoir, comprising fallen logs, snags, and stumps, markedly affects carbon dynamics over decades. In this study, deadwood carbon stocks were quantified using data from 2674 sites in Japan surveyed between 2011 and 2015 via the National Forest Soil Carbon Inventory, and the deadwood carbon attributes in the country were explored. Deadwood were surveyed using the line intersect method for fallen logs and the belt transect method for stumps and snags. In Japan, the deadwood carbon stock (measured in t-C/ha) was quantified at 7.5 ± 9.74 (mean ± SD), with fallen logs at 3.26 ± 4.43, stumps at 2.45 ± 5.69, and snags at 1.80 ± 5.27, with significant differences detected among these stocks (p

Abstract Background Carbon (C) sink and stock are among the most important ecosystem services provided by forests in climate change mitigation policies. In this context, old-growth forests constitute an essential reference point for the development of close-to-nature silviculture, including C management techniques. Despite their small extent in Europe, temperate old-growth forests are assumed to be among the most prominent in terms of biomass and C stored. However, monitoring and reporting of C stocks is still poorly understood. To better understand the C stock amount and distribution in temperate old-growth forests, we estimated the C stock of two old-growth stands in the Dinaric Alps applying different assessment methods, including direct and indirect approaches (e.g., field measurements and allometric equations vs. IPCC standard methods). This paper presents the quantification and the distribution of C across the five main forest C pools (i.e., aboveground, belowground, deadwood, litter and soil) in the study areas and the differences between the applied methods. Results We report a very prominent C stock in both study areas (507 Mg C ha− 1), concentrated in a few large trees (36% of C in 5% of trees). Moreover, we found significant differences in C stock estimation between direct and indirect methods. Indeed, the latter tended to underestimate or overestimate depending on the pool considered. Conclusions Comparison of our results with previous studies and data collected in European forests highlights the prominence of temperate forests, among which the Dinaric Alps old-growth forests are the largest. These findings provide an important benchmark for the development of future approaches to the management of the European temperate forests. However, further and deeper research on C stock and fluxes in old-growth stands is of prime importance to understand the potential and limits of the climate mitigation role of forests.

The creation of artificial snags, so-called high stumps, within forest management operations is a recently established tool to enrich standing deadwood as a habitat for saproxylic species. In this study, we analysed the impact of active high stump management on saproxylic beetle species. We selected 63 high stumps in six Bavarian forest districts (Germany), which were felled and subjected to close examination, focusing on beetle (Coleoptera) colonization. We identified 63 emerged coleopteran species belonging to 29 families; a further 10 taxa were identified only at the genus or family level, respectively. Moreover, 17% of the obtained taxa are listed in the German Red List of Coleoptera. Furthermore, 32% of the examined high stump trunks, predominantly broad-leaved tree species, harboured Red List beetle taxa. In particular, trembling aspen (Populus tremula) showed a disproportionately high number of Red List beetle species. The total species richness of beetles was independent of the height, diameter and decay stage of the snags. High stumps (snags) containing Red List beetle species tended to have higher amounts of deadwood in their surroundings, but the difference was not significant. According to the results of our study, actively creating high stumps proved to be a suitable method for creating habitats and serve as stepping-stones for endangered saproxylic species. Proactive high stump management during harvest can be a valuable component of deadwood management and biodiversity protection in forests. [ABSTRACT FROM AUTHOR]

The deadwood contributes to an increase in soil heterogeneity due to the changing the microrelief (by the formation of windthrow-soil complexes), as well as changes in physical and chemical characteristics of decaying wood directly during xylolysis. We hypothesized that fallen logs as an element of microrelief influence the species composition and cover structure of vascular plants. We studied the influence of Picea abies (L.) Karst fallen logs of moderate and advanced decay stages on the horizontal distribution and heterogeneity of vascular plant cover in different microsite types (small boreal grass type, blueberry type, small boreal grass-blueberry type, herbs, and blueberry type) in old-growth middle taiga spruce forest in the Kivach State Nature Reserve (Republic of Karelia, Russia). The fallen deadwood acts as a factor of heterogeneity, causing reversible changes in the homogeneity of the original plant cover. The decaying logs influence the horizontal distribution of small herbs by changing the occurrence and density of shoots of Oxalis acetosella L., Maianthemum bifolium (L.) F.W. Schmidt, Vaccinium myrtillus L., and Vaccinium vitis-idaea L., as well as the occurrence of Luzula pilosa (L.) Willd. and Calamagrostis arundinacea (L.) Roth. Its impact on the heterogeneity parameters can be traced up to 20 cm from the log. The differences in vascular plant cover between fallen logs and the surrounding forest floor depend on the soil conditions of the microsite. The heterogeneity of conditions created by the logs smoothed out with increasing decay class, resulting in decreasing differences in the heterogeneity parameters of vascular plant cover between deadwood and forest floor. The changes in the homogeneity of the initial vascular plant cover by deadwood and the gradual smoothing of heterogeneity between the logs and the forest floor in rich and poor conditions have different, mainly opposite, trends. Finally, the structure of the vegetation cover reaches a state that is typical of particular growth conditions beyond deadwood. [ABSTRACT FROM AUTHOR]

The preservation of national parks has emerged as a significant component of Indonesia's climate mitigation efforts, primarily due to its substantial carbon stocks. However, little is known about the potential carbon stored in deadwoods within these areas. This study aims to estimate fallen deadwood carbon stocks in four national parks in Indonesia. The results show that the density of deadwood in study areas ranges from 0.26 - 0.79 g cm-3. Deadwood volume varies between 247.37 - 388.50 cm³. Bukit Tigapuluh National Park has the highest fallen deadwood biomass and carbon stock, accounting for 261.35 and 122.83 tons ha-1, respectively, followed by Sebangau National Park (187.41 and 88.08 tons ha-1), Kutai National Park (139.91 and 65.76 tons ha-1) and Lore Lindu National Park (87.90 and 41.32 tons ha-1). This study also found that large deadwood with diameters of >7.5 cm contributes to more than 80% of the total deadwood carbon stock. Understanding the carbon stock stored in deadwood within national park areas is crucial for refining estimates of potential avoided greenhouse gas emissions resulting from the conservation of national park forests. [ABSTRACT FROM AUTHOR]

This study investigated the diversity and ecology of deadwood-inhabiting mushrooms in Yankari Game Reserve. Stratified random sampling was used for the data collection. A total of 23 different mushroom species belonging to 12 different families were found growing on deadwood in the study area, with Polyporaceae and Hymenochaetaceae as the most dominant mushroom families. The distribution, composition, and diversity of the different mushroom species differed according to their local habitats, growth substrate and tree species. The habitats with the highest mushroom species diversity were the Lowland Combretaceous Woodland, Pteleopsis habeensis Woodland. Their Shannon Index (H′) values were 2.31 and 1.96 respectively, and Simpson Index (D) values were 6.81 and 4.74, respectively. Their mushroom abundance was significantly (α = 0.05, p = 0.00) higher than that of Afzelia africana Woodland and Upland Combretaceous Woodland. The Main Trunk was the growth substrate with the highest H′ and D, which were 2.11 and 6.32, respectively; while the Branch had a significantly (α = 0.05, p = 0.00) higher abundance of mushrooms than the soil. Pteleopsis habeensis was the tree species that had the highest mushroom species richness and abundance with H′ (2.06) and D (5.07). The P. habeensis had significantly (α = 0.05, p = 0.00) higher mushroom abundance than all the rest of the thirteen different tree species. Trametes pubescens was the most abundant mushroom species, which was significantly (α = 0.05, p = 0.00) higher than the abundance of 10 species other mushroom species found in the study area. The result of this study can help forest managers conserve the diversity of deadwood-inhabiting mushrooms.

Nanopore raw read accuracy has improved to over 99%, making it a potential tool for metabarcoding. For broad adoption, guidelines on quality filtering are needed to ensure reliable taxonomic unit recovery. This study aims to provide those guidelines for a fungal metabarcoding context and to apply them to a case study of ectomycorrhizae in the decaying bark of Fagus sylvatica. We introduce the eNano pipeline to test two standard metabarcoding approaches: (1) Reference-based mapping leveraging UNITE’s species hypothesis system (SH approach); (2) Constructing 98% OTUs (OTU approach). Our results demonstrate that both approaches are effective with Nanopore data. When using a reference database, we recommend strict mapping criteria rather than Phred-based filtering. Leveraging the SH-system further enhances reproducibility and facilitates cross-study communication. For the 98% OTUs, filtering reads at ≥Q25 is recommended. Our case study reveals that the decay gradient is a primary determinant of community composition and that specific mycorrhizal fungi colonize decaying bark. Complementing our metabarcoding results with root tip morphotypification, we identify Laccaria amethystina and Tomentella sublilacina as key ectomycorrhizae of saplings on decaying logs. These findings demonstrate that Nanopore sequencing can provide valuable ecological insights and support its broader use in fungal metabarcoding as read quality continues to improve.

Restoration of degraded habitat is frequently used in ecological compensation. However, ecological restoration suffers from innate problems of long delivery times of features shown to be good proxies for biodiversity, e.g., large dead trees. We tested a possible way to circumvent this problem; the translocation of hard-to-come deadwood substrates from an impact area to a compensation area. Following translocation, deadwood density in the compensation area was locally equivalent to the impact area, around 20 m3 ha−1, a threshold for supporting high biodiversity of rare and red-listed species. However, deadwood composition differed between the impact and compensation area, showing a need to include more deadwood types, e.g., late decomposition deadwood, in the translocation scheme. To guide future compensation efforts, the cost for translocation at different spatial scales was calculated. We conclude that translocation of deadwood could provide a cost-efficient new tool for ecological compensation/restoration but that the method needs refinement. [ABSTRACT FROM AUTHOR]

Biodiversity loss due to intensive timber production is a ubiquitous conservation issue across temperate and boreal forest ecosystems. Retention forestry, the retention of deadwood and old-growth features within production forest, is one management strategy that has been implemented in various countries around the world to conserve a wide range of taxa within managed forests. The success and ecological implications of retention forestry are currently subject to intensive investigation and while some taxa like birds and insects have already been studied frequently, larger mammals have received less attention. Pine martens are one of the few larger mammals in central Europe preferring older forest and potentially profiting directly from deadwood retention as a consequence of implemented retention forestry. The goal of our study was to assess the response of European marten species to deadwood retention in montane mixed forests. Using marten detection rates from camera traps on 135 research plots we assessed the response of martens to deadwood at three different spatial scales using generalized linear mixed models. We found no effect of lying deadwood on marten detections at the plot scale (1 ha) or in a 10 m radius around the camera traps. However, we found a significant increase of marten detections if logs (> 10 cm in diameter) were directly in front and in view of the camera trap. Our results show that deadwood retention as a measure of retention forestry does affect microhabitat use of martens, but not stand selection during the growing season. Logs directly in view of the camera trap increase marten detection rates as martens choose to move and forage along fallen trees when they are available. When using camera trapping to collect data on martens, trap positioning in front of logs can heavily bias trapping results when unaccounted for. [ABSTRACT FROM AUTHOR]

The impact of deadwood in ecosystems is dependent on its longevity, as determined by decay rates controlled by decay agents. Despite the importance of macroclimate, significant variation of decay rates within a given macroclimatic envelope has been reported. Such variation may be driven by local‐scale microenvironmental conditions as regulated by the plant community structure as well as the presence of specific biotic and abiotic decay agents, decoupling the relation between macroclimate conditions and deadwood decay rates. In this study, we evaluated the relation between local‐scale variation in plant community structure with the decay rates of deadwood and the relative importance of biotic and abiotic decay agents in deadwood decay in Neotropical Cerrado. For this, we performed a wood mass loss experiment using Pinus taeda wood which was installed at three sites in three vegetation types differing in canopy cover—grasslands, savannas and woodlands; wood was divided into treatments according to deadwood exposure to decay agents—microorganism, termite and solar radiation. Across sites, we found termites and microbes decomposed wood twice as fast as microbes alone, while solar radiation was not a strong driver of deadwood decay in our sites. Additionally, local‐scale variation in plant community structure affected deadwood decay, as decay rates and frequency of wood blocks discovered by termites were lower in woodlands than in grasslands and savannas. Our study highlights the interactive effects of local‐scale variation in plant community structure and termites on deadwood turnover, mainly due to differences in termite foraging behaviour among vegetation types and highlights the key role of termites in deadwood decay throughout Neotropical savannas. [ABSTRACT FROM AUTHOR]

Assessments of synergies and trade-offs between climate change mitigation and forest biodiversity conservation have focused on set-aside areas. We evaluated a more comprehensive portfolio of silvicultural management adaptations to climate change and conservation measures exemplary for managed European beech forests. Based on the available literature, we assessed a range of common silvicultural management and conservation measures for their effects on carbon sequestration in forest and wood products and for substituting more carbon-intensive products. We complemented this review with carbon sequestration simulations for a typical mountainous beech forest region in Austria. We propose three priority actions to enhance the synergies between climate change mitigation and biodiversity. First, actively increase the proportion of European beech in secondary Norway spruce forests, even though beech will not be unaffected by expected water supply limitations. Secondly, optimize the benefits of shelterwood systems and promote uneven-aged forestry, and thirdly, enhance mixed tree species. Targeted conservation measures (deadwood, habitat trees, and old forest patches) increase the total C storage but decrease the annual C sequestration in forests, particularly in wood products. The establishment of a beech wood market with an extended product portfolio to reduce the use of fuelwood is essential for sustainable climate change mitigation. Since there are limitations in the production of saw timber quality beech wood on low fertility sites, C accumulation, and biodiversity can be emphasized in these areas. [ABSTRACT FROM AUTHOR]

Copyright of Acta Silvae et Ligni is the property of Biotechnical Faculty, Slovenian Forestry Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In an attempt to reconcile wood extraction and forest biodiversity in managed boreal forests, ecosystem-based forest management (EBM) has become the de facto management approach. Retention forestry represents one prominent way that EBM is implemented in many parts of the world. Retention patches commonly left after harvesting serve as analogues of fire island remnants, which are patches of unburned forests in the burned forest matrix. Although the persistence of retention patches has been questioned, few studies have attempted to quantitatively compare forest attributes in both burned and harvested forests. As part of a larger program examining multiple aspects of ecosystem function in fire and harvest island remnants, we investigated the impact of disturbance type (fire/harvest) and forest edges on C stock in snags and coarse woody debris (CWD) found in island remnants in mixedwood boreal forests of Alberta, Canada. Total C stock (in snags and CWD) was similar between the two disturbance types and edge plots had similar total deadwood C stocks to interiors. The edges of island remnants had about two-fold more snag C stock than their interiors in both disturbance types, but C stock in CWD was unaffected by edge effects and disturbance type. Our results suggest that deadwood C dynamics in island remnants in fire and harvest disturbed boreal forests were similar, thus lending support for the continued implementation of retention forestry in Alberta. [ABSTRACT FROM AUTHOR]

In the last century, eucalypt plantations are increasing all over the world. Concretely, in the Basque Country (northern Iberian Peninsula), 7% of pine plantations have been recently substituted by eucalypt plantations, where little is known about their ecological impact on soil and plant diversity. However, the most relevant impact is due to forest management, as Eucalyptus globulus Labill. plantations have a short harvesting cycle, 12-15 years rotations. In fact, the species is able to regenerate from stumps; therefore, those plantations are replanted after 3-4 rotations. This type of invasive and frequent management could lead to further adverse effects on the ecosystem. The aim of this study was to characterise and compare the eucalypt plantations newly established (New: never been harvested) with older ones (Old: several times harvested and grown from stumps), having been established for at least 35 years, and to identify the primary factors that could influence the richness and diversity of vascular plant species in those plantations. The results indicated that both plantations exhibited comparable characteristics with respect to deadwood (volume and decay stage) and tree size and density. However, the Old plantations exhibited higher forest heterogeneity, pH, and higher shrub and herb richness and diversity. Overall, generalist and invasive species were found in the New plantations, while in the Old plantations, typical species of the native forests were also observed. The factor that influenced plant diversity was the volume of deadwood. Regarding life forms, higher altitude and proximity to watercourses favoured tree diversity; and lower canopy cover, shrub diversity. In conclusion, the longer the plantation has been established, the greater the number of species that are able to survive and adapt. This is probably due to the fact that management disturbance is specific and not sufficient to remove the already established plants and the soil seed bank. [ABSTRACT FROM AUTHOR]

Deadwood in forests plays a critical role in maintaining the ecological functions. Small mammals use deadwood, and thus deadwood can mitigate the negative impacts of plantation on small mammals. This study focused on fallen dead trees in planted forests, and aimed to verify whether fallen dead trees affect behavioral patterns of Japanese squirrels. To clarify the use of fallen dead trees by Japanese squirrels in a Japanese cedar plantation, we observed squirrel behavior by camera trap surveys at 61 survey sites. Our findings showed that fallen dead trees play a crucial role in the behavior of Japanese squirrels, serving as landmarks for movement, vigilance, resting, and hoarding sites. These functions are critical for the survival of Japanese squirrels, suggesting that fallen dead trees in planted forests have positive impacts on their microenvironment use. The increase of deadwood due to disturbances such as heavy rainfall and snowfall resulting from climate change may provide benefits to arboreal small mammals in poorly managed planted forests. Additionally, leaving some of the deadwood generated during the harvesting process in properly managed forests can improve the quality of habitat for arboreal small mammals.

In the last century, eucalypt plantations are increasing all over the world. Concretely, in the Basque Country (northern Iberian Peninsula), 7% of pine plantations have been recently substituted by eucalypt plantations, where little is known about their ecological impact on soil and plant diversity. However, the most relevant impact is due to forest management, as Eucalyptus globulus Labill. plantations have a short harvesting cycle, 12–15 years rotations. In fact, the species is able to regenerate from stumps; therefore, those plantations are replanted after 3–4 rotations. This type of invasive and frequent management could lead to further adverse effects on the ecosystem. The aim of this study was to characterise and compare the eucalypt plantations newly established (New: never been harvested) with older ones (Old: several times harvested and grown from stumps), having been established for at least 35 years, and to identify the primary factors that could influence the richness and diversity of vascular plant species in those plantations. The results indicated that both plantations exhibited comparable characteristics with respect to deadwood (volume and decay stage) and tree size and density. However, the Old plantations exhibited higher forest heterogeneity, pH, and higher shrub and herb richness and diversity. Overall, generalist and invasive species were found in the New plantations, while in the Old plantations, typical species of the native forests were also observed. The factor that influenced plant diversity was the volume of deadwood. Regarding life forms, higher altitude and proximity to watercourses favoured tree diversity; and lower canopy cover, shrub diversity. In conclusion, the longer the plantation has been established, the greater the number of species that are able to survive and adapt. This is probably due to the fact that management disturbance is specific and not sufficient to remove the already established plants and the soil seed bank.

In an attempt to reconcile wood extraction and forest biodiversity in managed boreal forests, ecosystem-based forest management (EBM) has become the de facto management approach. Retention forestry represents one prominent way that EBM is implemented in many parts of the world. Retention patches commonly left after harvesting serve as analogues of fire island remnants, which are patches of unburned forests in the burned forest matrix. Although the persistence of retention patches has been questioned, few studies have attempted to quantitatively compare forest attributes in both burned and harvested forests. As part of a larger program examining multiple aspects of ecosystem function in fire and harvest island remnants, we investigated the impact of disturbance type (fire/harvest) and forest edges on C stock in snags and coarse woody debris (CWD) found in island remnants in mixedwood boreal forests of Alberta, Canada. Total C stock (in snags and CWD) was similar between the two disturbance types and edge plots had similar total deadwood C stocks to interiors. The edges of island remnants had about two-fold more snag C stock than their interiors in both disturbance types, but C stock in CWD was unaffected by edge effects and disturbance type. Our results suggest that deadwood C dynamics in island remnants in fire and harvest disturbed boreal forests were similar, thus lending support for the continued implementation of retention forestry in Alberta.

The mountain forests of the Northwestern Caucasus represent unique refugia for the native biodiversity of flora and fauna. Endemic species are also preserved among soil invertebrates, including the group of earthworms, which are important ecosystem engineers. This study assesses the spatial distribution of the endemic anecic species of earthworms Dendrobaena nassonovi nassonovi Kulagin, 1889 in deciduous, coniferous–deciduous, small-leaved, and conifer forests of the Northwestern Caucasus (a total of 1028 geographical points were surveyed, of which the species was found in 185 points) based on our own field data by modeling the current potential areas using the Maxent software. The D. n. nassonovi potential area maps show a high probability of the species inhabiting mid- and high-mountain forests of the Northwestern Caucasus and being confined to mixed coniferous–deciduous and beech forests. The optimum soil and climatic parameters, as well as a lack of large-scale business operations in the mid- and high-mountain forests, make it possible for these ecosystems to remain suitable refugia, in particular for the endemic anecic species of Caucasus earthworms D. n. nassonovi. [ABSTRACT FROM AUTHOR]

Much remains unknown regarding the linkages between forest structure and microclimate as they regulate detrital decomposition. In this study, we use a factorial field experiment that included canopy gap creation and downed woody material (DW) additions conducted in a mature northern hardwood forest. Our objectives were to (1) test the individual and combined effects of canopy gaps and DW additions on detrital mass loss; (2) determine whether the factors regulating mass loss are similar among leaf litter, experimental wood stakes, and coarse DW; and (3) assess the microclimatic variables that most strongly influence mass loss of these detrital types. After three years, leaf litter mass loss within gaps, without or with DW additions, was significantly greater than that of any non-gap treatments. Mass loss of stakes was significantly greater in gaps, intermediate in gaps with DW additions, and lowest in non-gap treatments. Mass loss of wood stakes after 8 years varied by species, with aspen (Populus tremuloides) losing up to 93% and sugar maple (Acer saccharum) up to 82% of its original mass. Fourteen years following treatment, the experimental logs lost 55–70% of their original mass, with ash (Fraxinus spp.) decaying faster than maple. Gap creation and DW additions individually, but not in combination, increased mass loss of coarse DW. For most substrates tested, gaps were consistently and positively related to mass loss, with approximately 10% greater mass loss in gaps compared to non-gaps. The presence of deadwood strongly moderated litter decomposition, had minimal effect on small woody substrates in the short-term after gap creation, but was influential on longer-term decay patterns of larger DW. Predictive models for each substrate varied, though shared some similar drivers. Litter mass loss was positively correlated to increasing gap size, canopy openness, and soil moisture. Stake mass loss was positively correlated to increasing gap size and canopy openness for maple, but soil temperature for aspen. Mass loss for logs was driven by increasing DW volume and gap size for ash, but soil temperature for maple. Smaller-sized materials may be more sensitive to environmental conditions as opposed to logs for which microclimatic influence may lag or remain a minor driver for at least the initial decade of decomposition. Regardless of substrate type, the findings of this work highlight the potential for greater rates of detrital mass loss from forest systems under predicted increases in canopy disturbance rates with climate change and invasive insects and diseases. [ABSTRACT FROM AUTHOR]

Functional trait approaches are common in ecology, but a lack of clear hypotheses on how traits relate to environmental gradients (i.e., trait–niche relationships) often makes uncovering mechanisms difficult. Furthermore, measures of community functional structure differ in their implications, yet inferences are seldom compared among metrics. Community‐weighted mean trait values (CWMs), a common measure, are largely driven by the most common species and thus do not reflect community‐wide trait–niche relationships per se. Alternatively, trait–niche relationships can be estimated across a larger group of species using hierarchical joint species distribution models (JSDMs), quantified by a parameter Γ. We investigated how inferences about trait–niche relationships are affected by the choice of metric. Using deadwood‐dependent (saproxylic) beetles in fragmented Finnish forests, we followed a protocol for investigating trait–niche relationships by (1) identifying environmental filters (climate, forest age, and deadwood volume), (2) relating these to an ecological function (dispersal ability), and (3) identifying traits related to this function (wing morphology). We tested 18 hypothesized dispersal relationships using both CWM and Γ estimates across these environmental gradients. CWMs were more likely than Γ to show support for trait–niche relationships. Up to 13% of species' realized niches were explained by dispersal traits, but the directions of effects were consistent with fewer than 11%–39% of our 18 trait–niche hypotheses (depending on the metric used). This highlights the difficulty in connecting morphological traits and ecological functions in insects, despite the clear conceptual link between landscape connectivity and flight‐related traits. Caution is thus warranted in hypothesis development, particularly where apparent trait–function links are less clear. Inferences differ when CWMs versus Γ estimates are used, necessitating the choice of a metric that reflects study questions. CWMs help explain the effects of environmental gradients on community trait composition, whereas the effects of traits on species' niches are better estimated using hierarchical JSDMs. [ABSTRACT FROM AUTHOR]

Deadwood in forests plays a critical role in maintaining the ecological functions. Small mammals use deadwood, and thus deadwood can mitigate the negative impacts of plantation on small mammals. This study focused on fallen dead trees in planted forests, and aimed to verify whether fallen dead trees affect behavioral patterns of Japanese squirrels. To clarify the use of fallen dead trees by Japanese squirrels in a Japanese cedar plantation, we observed squirrel behavior by camera trap surveys at 61 survey sites. Our findings showed that fallen dead trees play a crucial role in the behavior of Japanese squirrels, serving as landmarks for movement, vigilance, resting, and hoarding sites. These functions are critical for the survival of Japanese squirrels, suggesting that fallen dead trees in planted forests have positive impacts on their microenvironment use. The increase of deadwood due to disturbances such as heavy rainfall and snowfall resulting from climate change may provide benefits to arboreal small mammals in poorly managed planted forests. Additionally, leaving some of the deadwood generated during the harvesting process in properly managed forests can improve the quality of habitat for arboreal small mammals. [ABSTRACT FROM AUTHOR]

This study examines microhabitat abundance and composition on retention trees in 20 young stands in Latvia that were clear-cut between 2002 and 2004. Retention trees play a vital role in sustaining biological diversity after clear-cutting, but their mortality rate is often high due to post-harvest environmental changes. This study compares tree-related microhabitat (TreM) abundance and composition on retention trees of different dimensions, species, and vitality. The tree height and diameter were measured, and the living status and position of each tree were determined. The research questions of the study were to assess the relationships between TreMs, tree dimensions, and species, as well as to compare the occurrence of TreMs on living and dead wood. The comprehensive analysis revealed that larger tree diameters and specific tree species (Populus tremula, Fraxinus excelsior, and Salix caprea) lead to a higher abundance of TreMs. The results also highlighted the importance of preserving deadwood within forest stands as it enhances the observed abundance of TreMs. This study provides the missing information on TreMs in Latvia, thus providing data for comparison in a wider region. [ABSTRACT FROM AUTHOR]

In the managed beech forests of Central Italy (Molise), the diversity of saproxylic species is potentially under threat by intensive management. To evaluate the impact of forestry on the biodiversity of these ecosystems, we analyzed the relationship between abundance of saproxylic beetles and (i) forest stand exposure and elevation, (ii) deadwood availability (coarse woody debris - CWD - and stumps), (iii) abundance of microhabitats. Four sampling sectors with different altitudes and exposure were identified in a 400-ha study area in the Appenine mountains. Fifteen circular plots (13 m radius) were established in each sector where deadwood and microhabitats were surveyed and saproxylic beetles sampled. We fitted joint species distribution models to quantify the relationship between forest attributes and saproxylic species’ abundance, including the interactions with their family and trophic category. Overall, 2334 specimens belonging to 64 species of saproxylic beetles were collected. Both abundance and species richness were higher in the sectors with high elevation (respectively, 55% and 44%) and South exposure (respectively, 28% and 44%). Average deadwood volumes were low (stumps: 7.6 m3 ha-1; CWD: 0.3 m3 ha-1; snags: 0.4 m3 ha-1), and insect galleries were the most abundant microhabitat (380 records over a total of 434). The most important variables affecting abundance were stump characteristics (model deviance = 81.2), elevation (deviance = 64.7), and CWD characteristics (deviance = 58.0). Our results show that topographical variables and forest structure jointly affect the abundance patterns of saproxylic beetle communities in managed beech forests. These ecological interactions imply that management has different impacts on the saproxylic communities in different topographic conditions. To acknowledge this complexity we advocate for a landscape-level forest management supporting the local beetle diversity maintaining a mosaic of semi-natural forest characteristics in different topographic contexts. The ecological value of the forest landscape will be further enhanced by the application of closer-to-nature management interventions based on deadwood retention, microhabitat creation and tree retention, in line with the guidelines of the new EU Forest Strategy for 2030.

The creation of artificial snags, so-called high stumps, within forest management operations is a recently established tool to enrich standing deadwood as a habitat for saproxylic species. In this study, we analysed the impact of active high stump management on saproxylic beetle species. We selected 63 high stumps in six Bavarian forest districts (Germany), which were felled and subjected to close examination, focusing on beetle (Coleoptera) colonization. We identified 63 emerged coleopteran species belonging to 29 families; a further 10 taxa were identified only at the genus or family level, respectively. Moreover, 17% of the obtained taxa are listed in the German Red List of Coleoptera. Furthermore, 32% of the examined high stump trunks, predominantly broad-leaved tree species, harboured Red List beetle taxa. In particular, trembling aspen (Populus tremula) showed a disproportionately high number of Red List beetle species. The total species richness of beetles was independent of the height, diameter and decay stage of the snags. High stumps (snags) containing Red List beetle species tended to have higher amounts of deadwood in their surroundings, but the difference was not significant. According to the results of our study, actively creating high stumps proved to be a suitable method for creating habitats and serve as stepping-stones for endangered saproxylic species. Proactive high stump management during harvest can be a valuable component of deadwood management and biodiversity protection in forests.

Abstract Functional trait approaches are common in ecology, but a lack of clear hypotheses on how traits relate to environmental gradients (i.e., trait–niche relationships) often makes uncovering mechanisms difficult. Furthermore, measures of community functional structure differ in their implications, yet inferences are seldom compared among metrics. Community‐weighted mean trait values (CWMs), a common measure, are largely driven by the most common species and thus do not reflect community‐wide trait–niche relationships per se. Alternatively, trait–niche relationships can be estimated across a larger group of species using hierarchical joint species distribution models (JSDMs), quantified by a parameter Γ. We investigated how inferences about trait–niche relationships are affected by the choice of metric. Using deadwood‐dependent (saproxylic) beetles in fragmented Finnish forests, we followed a protocol for investigating trait–niche relationships by (1) identifying environmental filters (climate, forest age, and deadwood volume), (2) relating these to an ecological function (dispersal ability), and (3) identifying traits related to this function (wing morphology). We tested 18 hypothesized dispersal relationships using both CWM and Γ estimates across these environmental gradients. CWMs were more likely than Γ to show support for trait–niche relationships. Up to 13% of species' realized niches were explained by dispersal traits, but the directions of effects were consistent with fewer than 11%–39% of our 18 trait–niche hypotheses (depending on the metric used). This highlights the difficulty in connecting morphological traits and ecological functions in insects, despite the clear conceptual link between landscape connectivity and flight‐related traits. Caution is thus warranted in hypothesis development, particularly where apparent trait–function links are less clear. Inferences differ when CWMs versus Γ estimates are used, necessitating the choice of a metric that reflects study questions. CWMs help explain the effects of environmental gradients on community trait composition, whereas the effects of traits on species' niches are better estimated using hierarchical JSDMs.

Most European forests are used for timber production. Given the limited extent of unmanaged (and especially primary) forests, it is essential to include commercial forests in the conservation of forest biodiversity. In order to develop ecologically sustainable forest management practices, it is important to understand the management impacts on forest-dwelling organisms. Experiments allow testing the effects of alternative management strategies, and monitoring of multiple taxa informs us on the response range across forest-dwelling organisms. To provide a representative picture of the currently available information, metadata on 28 multi-taxa forest management experiments were collected from 14 European countries. We demonstrate the potential of compiling these experiments in a single network to upscale results from the local to continental level and indicate directions for future research. Among the different forest types, temperate deciduous beech and oak-dominated forests are the best represented in the multi-taxa management experiments. Of all the experimental treatments, innovative ways of traditional management techniques (e.g., gap cutting and thinning) and conservation-oriented interventions (e.g., microhabitat enrichment) provide the best opportunity for large-scale analyses. Regarding the organism groups, woody regeneration, herbs, fungi, beetles, bryophytes, birds and lichens offer the largest potential for addressing management–biodiversity relationships at the European level. We identified knowledge gaps regarding boreal, hemiboreal and broadleaved evergreen forests, the treatments of large herbivore exclusion, prescribed burning and forest floor or water manipulations, and the monitoring of soil-dwelling organisms and some vertebrate classes, e.g., amphibians, reptiles and mammals. To improve multi-site comparisons, design of future experiments should be fitted to the set-up of the ongoing projects and standardised biodiversity sampling is suggested. However, the network described here opens the way to learn lessons on the impact on forest biodiversity of different management techniques at the continental level, and thus, supports biodiversity conservation in managed forests.

After large and severe wildfires, the establishment of tree regeneration, particularly for species without specific fire-adaptive traits, can be challenging. Within harsh environments, the presence of favorable microsites, as those provided by deadwood, enhancing microclimatic conditions, is crucial to the re-establishment of forest cover and thus to foster recovery dynamics. Active restoration strategies can have an impact on these dynamics, altering or hindering them. The main hypothesis of this study is that manipulating deadwood in terms of quantity and spatial arrangement can result in differences in natural regeneration density and composition. Post-disturbance regeneration dynamics and the role played by deadwood over time in the creation of safe sites for seedling establishment were investigated in an area affected by a high-severity wildfire that underwent different post-fire restoration treatments along a gradient of increasing deadwood manipulation, spanning from salvage logging to non-intervention. Two inventories were performed 5 and 11 years after the fire. Ground cover proportion was significantly different among treatments, with lower values of lying deadwood in salvaged sites. A higher probability of regeneration establishment close to deadwood was found in both surveys, confirming the facilitating role of deadwood on post-fire forest regeneration. Microsite dynamics resulting from deadwood facilitation were highlighted, with establishment probability and anisotropic relationships between deadwood elements and seedlings changing over time, as recovery processes slowly improved environmental conditions. In dry mountain areas affected by stand-replacing wildfires, by removing deadwood, salvage logging reduces the number of safe sites for regeneration, further impairing the ecosystem recovery. Passive management should be the ecologically preferred management strategy in these conditions, although intermediate interventions (e.g., felling without delimbing, leaving deadwood on the ground) could be effective alternatives, accelerating snag fall dynamics and immediately increasing favorable microsite availability. [ABSTRACT FROM AUTHOR]

Selective browsing by deer on young trees may impede the management goal of increasing forest resilience against climate change and other disturbances. Deer population density is often considered the main driver of browsing impacts on young trees, however, a range of other variables such as food availability also affect this relationship. In this study, we use browsing survey data from 135 research plots to explore patterns of roe deer (Capreolus capreolus) browsing pressure on woody plants in mountainous forests in central Europe. We fitted species‐specific generalised linear mixed models for eight woody taxa, assessing the potential effects of understory characteristics, roe deer abundance and lying deadwood on browsing intensity. Our study reveals conspecific and associational effects for woody taxa that are intermediately browsed by roe deer. Selective browsing pressure was mediated by preferences of plants, in that, browsing of strongly preferred woody taxa as for example mountain ash (Sorbus aucuparia) and of least preferred woody taxa, for example Norway spruce (Picea abies) was not affected by the surrounding understory vegetation, while browsing pressure on intermediately browsed species like for example silver fir (Abies alba) was affected by understory characteristics. Contrary to our expectations, roe deer abundance was only positively associated with browsing pressure on silver fir and bilberry (Vaccinium myrtillus), while all other plants were unaffected by deer abundance. Finally, we did not find an influence of lying deadwood volume on the browsing pressure on any woody‐plant species. Overall, our results indicate that patterns in browsing preference and intensity are species‐specific processes and are partly affected by the surrounding understory vegetation. Current management strategies that aim to reduce browsing pressure through culling may be inefficient as they do not address other drivers of browsing pressure. However, managers also need to consider the characteristics of the local understory vegetation in addition to deer abundance and design species‐specific plans to reduce browsing on woody plant taxa. [ABSTRACT FROM AUTHOR]

Scapania apiculata, Scapania carinthiaca, and Scapania scapanioides are rare deadwood-dwelling liverworts threatened across Europe. Scapania carinthiaca is thus listed in the Habitats Directive. However, their distribution data are scattered, and their ecologic demands are insufficiently studied. Here, we present new locations and data on the ecology of the species, which resulted from a targeted search in selected regions of Austria. We found ten new sites each for Scapania apiculata and Scapania scapanioides and twenty for Scapania carinthiaca. Reproduction was exclusively asexual. The macroclimates of all known locations in Austria did not differ significantly between the three species. It was consistently wet, with a mean annual precipitation of 1615.3 mm, a high evenness of rainfall, and a low desiccation risk. The mean temperature averaged 7.4 °C. The habitat was shaded dead wood of Picea abies, Abies alba, and Fagus sylvatica of all decay stages at a median distance of 2.5 m from streams or springy areas in semi-natural forests of montane and submontane regions. Thus, high deadwood volumes under a suitable climate are a prerequisite for the occurrences of the species. The number of locations of new finds has more than doubled in Austria and thus in Europe. [ABSTRACT FROM AUTHOR]

The species‐energy hypothesis predicts increasing biodiversity with increasing energy in ecosystems. Proxies for energy availability are often grouped into ambient energy (i.e., solar radiation) and substrate energy (i.e., non‐structural carbohydrates or nutritional content). The relative importance of substrate energy is thought to decrease with increasing trophic level from primary consumers to predators, with reciprocal effects of ambient energy. Yet, empirical tests are lacking. We compiled data on 332,557 deadwood‐inhabiting beetles of 901 species reared from wood of 49 tree species across Europe. Using host‐phylogeny‐controlled models, we show that the relative importance of substrate energy versus ambient energy decreases with increasing trophic levels: the diversity of zoophagous and mycetophagous beetles was determined by ambient energy, while non‐structural carbohydrate content in woody tissues determined that of xylophagous beetles. Our study thus overall supports the species‐energy hypothesis and specifies that the relative importance of ambient temperature increases with increasing trophic level with opposite effects for substrate energy. [ABSTRACT FROM AUTHOR]

Deadwood is one of the main structural features of forest ecosystems and plays an important role in the nutrient cycle, in maintaining production and environmental heterogeneity, and acts as an indicator for assessing the biodiversity of forest ecosystems. This research was conducted with the aim of evaluating the quantitative and qualitative characteristics of deadwood according to the influence of forest accessibility indicators in a comparison between natural and recreational forests. The studied area was divided into three accessibility classes based on the slope gradient range, the slope direction towards the nearest road, the road type, and distance from the road. These classes were: Easy-recreational forest (RE-F), Medium-natural forest 1 (NA-F1), and Difficult-natural forest 2 (NA-F2). In each accessibility class, three transects (750 × 50 m) were established, and three deadwood groups (snag, log, and stump) were recorded along the transects and their volume was calculated. The results of the analysis of variance show that accessibility has a significant effect on the presence of deadwood. The number and volume of snags, logs and dead stumps per hectare was higher in NA-F2 than in NA-F1 and RE-F. In each of the investigated classes, logs and stumps had the highest and the lowest number and volume of deadwood per hectare, respectively. The snag longevity index (= log volume/snag volume) decreased with accessibility. NA F2 showed the greatest value, while REF and NA F1 were not significantly different from each other. The results show that decay classes DC2 in NA-F2 and DC3 in NA-F1 and RE-F had the highest percentage of decay frequency. Finally, the forest accessibility indicators have a significant effect on the quantity, quality and distribution of different groups of deadwood in the forest. This is related to the collection of deadwood by local people who remove deadwood with different levels of intensity. [ABSTRACT FROM AUTHOR]

The study aimed to quantify annual mortality and recruitment rates on permanent research plots in the Badínsky prales old-growth forest. The data measured in four stands originate from six censuses, which together cover a 48-year period. The mean annual mortality rate reached 4.2% (DBH > 2 cm) or 2.3% (DBH > 8 cm). The mortality peaked in the first part of the observation period, probably indicating an intermediate disturbance activity, and the subsequent declining trend led to minimum annual mortality during the last 20 years. We found substantially higher fir mortality in comparison with beech, primarily during the first decades of the measurement period. Among three size categories, the stems with DBH 2-8 cm showed the highest mortality rate. We detected the minimum fir recruitment rate throughout the observation period; on the other hand, the beech recruitment rate was relatively high responding to the open canopy. Standing and lying deadwood volumes indicated similar trends like mortality did, and high values of fir standing deadwood observed during the first decades can signify that a relatively high proportion of mortality was related to the fir decline caused by air pollution.

The objective of the manuscript was to study the effects of dead wood on macroinvertebrates (MI) assemblages occupying different habitat patches. Three streams were studied, with control and wooded sections in each stream from which MI were sampled for all substrate types (wood, fine detritus, gravel, sand). This contribution deals with three German streams Ihle, Nieplitz, and Verlorenwasser, which belong to the stream type 14 (sand-dominated lowland stream) and are located in the landscape unit Fläming. This type of stream, where large wood could be most influential, has been relatively understudied. This study focused on quantifying substrate distribution and macroinvertebrate taxonomy and performing statistical analysis of MI densities with regard to substrate type. The area-specific invertebrate assemblages were differentiated for MI density, dry matter density and taxonomic richness of invertebrates. In addition to macroinvertebrates, a special focus was on aquatic and semi-aquatic insects. There were significant differences between the control and wooden sections. The macroinvertebrate assemblages (individual density, dry matter density and species richness) of the detritus of the wood sections only in the Verlorenwasser was significantly and positively affected (two or three times) by the deadwood. Detritus in the wood sections of the Nieplitz and Verlorenwasser contained more sensitive species like EPT than detritus from the control sections. On the other hand, no significant difference in MI populations were determined for the sand of the wood sections compared to the sand of the control sections. In all water bodies, the wood substrate promoted all investigated indicators of macrozoobenthos as compared to sand of the wood sections. Detritus significantly promoted macrozoobenthos colonization in the wood sections as compared to sand of the Nieplitz and the Verlorenwasser. The MI density and dry matter density in the Ihle was also significantly promoted by detritus, although not significantly with regard species richness. Two significant correlations were also identified. The more sand that was present in the Ihle and the Verlorenwasser, the more the macroinvertebrate assemblages were inhibited. Additionally, the larger the area of detritus in the Ihle and the area of wood in the Nieplitz, the more MI populations were encouraged. The influence of the deadwood position on MI was also investigated, but there was no significant difference. Incline bridges, flow guides and parallel wood position types were settled in similar quality and quantity.

The occurrence of deadwood is inevitable during the process of plantation conversion, but the influences of conversion and the potential environmental effect on deadwood species diversity remain unclear. We established two fixed plots in Chinese fir thinned forest (TF) and Chinese fir and Michelia macclurei Dandy mixed forest (MF) (100 × 80 and 120 × 60 m2, respectively). We classified the deadwood into groups based on origin and by status, and analyzed deadwood species diversity using four common diversity indices. We also investigated the contribution of topographic factors to tree mortality using redundancy analysis. The species composition of deadwood differed markedly between the MF and TF. The species diversity and variety of deadwood status were greater for the TF than MF, although abundance was lower. Topography was poorly correlated with deadwood in the MF, while in the TF, altitude was strongly correlated with deadwood from Chinese fir, shade-intolerant late-coming populations, and fallen wood. Slope was negatively correlated with late-coming populations and fallen wood, but deadwood correlations with convexity were weak. These results indicate that cultivation methods strongly alter the species composition, status, abundance and diversity of deadwood in plantations. Topographic factors and targeted cultivation practices promote the formation of deadwood. [ABSTRACT FROM AUTHOR]

Deadwood is an important key ecological element for forest ecosystem biodiversity. Its low occurrence, especially in managed forests, makes inventory through field campaigns challenging. Remote sensing can provide a more objective and systematic approach to detect deadwood for large areas. Traditional area-based approaches have, however, shown limitations when it comes to predicting rare objects such as standing dead trees (SDT). To overcome this limitation, this study proposes a tree-based approach that uses a local maxima function to identify trees from airborne laser scanning (ALS) and optical data, and predict their status, i.e., living or dead, from normalized difference vegetation index (NDVI). NDVI was calculated from aerial images (hyperspectral and simulated aerial image) and from satellite images (PlanetScope and Sentinel-2). By comparing the different remotely sensed data sources, we aimed to assess the impact of spatial and spectral resolutions in the prediction of SDT. The presence/absence of SDT was perfectly predicted by combining trees identified using ALS-derived canopy height models with spatial resolutions between 0.75 m and 1 m and a search window size of 3 pixels, and NDVI computed from aerial images to predict their status. The presence/absence of SDT was not predicted as accurately when using NDVI computed from satellite images. A root-mean-square deviation of around 35 trees ha−1 was obtained when predicting the density of SDT with NDVI from aerial images and around 60 trees ha−1 with NDVI from satellite images. The tree-based approach presented in this study shows great potential to predict the presence of SDT over large areas. [ABSTRACT FROM AUTHOR]

Deadwood decomposition and other environmental processes mediated by microbial communities are generally studied with composite sampling strategies, where deadwood is collected from multiple locations in a large volume, that produce an average microbial community. In this study, we used amplicon sequencing to compare fungal and bacterial communities sampled with either traditional, composite samples, or small, 1 cm3 cylinders from a discrete location within decomposing European beech (Fagus sylvatica L.) tree trunks. We found that bacterial richness and evenness is lower in small samples when compared to composite samples. There was no significant difference in fungal alpha diversity between different sampling scales, suggesting that visually defined fungal domains are not restricted to a single species. Additionally, we found that composite sampling may obscure variation in community composition and this affects the understanding of microbial associations that are detected. For future experiments in environmental microbiology, we recommend that scale is explicitly considered as a factor and properly selected to correspond with the questions asked. Studies of microbial functions or associations may require samples to be collected at a finer scale than is currently practised. [ABSTRACT FROM AUTHOR]

The habitat quality of the littoral zone is of key importance for almost all lentic fish species. In anthropogenically created gravel pit lakes, the littoral zone is often structurally homogenized with limited fish habitats. We supplemented deadwood brush piles in the littoral zone of eight gravel pit lakes and investigated the diurnal and seasonal use of this and other typical microhabitats by six dominant fish species. Shoreline habitats were sampled using point abundance electrofishing during day and night in all four seasons, and patterns of fish abundance were compared amongst unstructured littoral habitats, emerged macrophytes and brush piles. We caught a total of 14,458 specimens from 15 species in the gravel pit lakes. Complex shoreline structures were used by all fish species that we examined, especially during daytime, whilst the use of unstructured habitats was highest during night. The newly added brush piles constituted suitable microhabitats for selected fish species, perch (Perca fluviatilis), roach (Rutilus rutilus) and pike (Esox lucius), particularly during winter. Supplemented deadwood provides suitable fish habitat in gravel pit lakes and may to some degree compensate for the loss of submerged macrophytes in winter by offering refuge and foraging habitat for selected fish species. [ABSTRACT FROM AUTHOR]

Beetles are one of the most diverse and often highly specialized groups among saproxylic organisms and play a key role in forest dynamics. To develop conservation plans in forests threatened by human activities, such as construction sites, it is crucial to identify key parameters characterizing forest structure in turn influencing saproxylic beetle diversity and abundance. Here, we investigate the difference in forest structure parameters and their cascading effect on saproxylic beetle communities between a forest site affected by the construction site expansion of the Turin–Lyon High-Speed Railway Line and a nearby second forest site. Our study showed differences in forest structure parameters between the two sites, in particular in the overall volume and diameter of coarse woody debris and in standing dead tree abundance. Even saproxylic beetle community structure was different between the two sites and this difference was linked to the different abundance and species richness of standing dead trees. Our findings provide information for the development of a local conservation plan for the saproxylic beetle community within forest habitats. Increasing the volume of deadwood and enriching tree diversity can locally sustain abundant and diverse communities and, eventually, support those species that are threatened by the building site expansion. [ABSTRACT FROM AUTHOR]

Abstract Selective browsing by deer on young trees may impede the management goal of increasing forest resilience against climate change and other disturbances. Deer population density is often considered the main driver of browsing impacts on young trees, however, a range of other variables such as food availability also affect this relationship. In this study, we use browsing survey data from 135 research plots to explore patterns of roe deer (Capreolus capreolus) browsing pressure on woody plants in mountainous forests in central Europe. We fitted species‐specific generalised linear mixed models for eight woody taxa, assessing the potential effects of understory characteristics, roe deer abundance and lying deadwood on browsing intensity. Our study reveals conspecific and associational effects for woody taxa that are intermediately browsed by roe deer. Selective browsing pressure was mediated by preferences of plants, in that, browsing of strongly preferred woody taxa as for example mountain ash (Sorbus aucuparia) and of least preferred woody taxa, for example Norway spruce (Picea abies) was not affected by the surrounding understory vegetation, while browsing pressure on intermediately browsed species like for example silver fir (Abies alba) was affected by understory characteristics. Contrary to our expectations, roe deer abundance was only positively associated with browsing pressure on silver fir and bilberry (Vaccinium myrtillus), while all other plants were unaffected by deer abundance. Finally, we did not find an influence of lying deadwood volume on the browsing pressure on any woody‐plant species. Overall, our results indicate that patterns in browsing preference and intensity are species‐specific processes and are partly affected by the surrounding understory vegetation. Current management strategies that aim to reduce browsing pressure through culling may be inefficient as they do not address other drivers of browsing pressure. However, managers also need to consider the characteristics of the local understory vegetation in addition to deer abundance and design species‐specific plans to reduce browsing on woody plant taxa.