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Applying biogeographical insights to the regulation of production forestry and the determination of forest reserve strategies is expected to increase the effectiveness of biodiversity conservation actions. Here, we assess the extent to which such applications take place. By using Sweden as a case study, we demonstrate fundamental differences among biogeographical regions in natural patterns and processes, past land-use, and anthropogenic impacts that need to be better incorporated into strategic conservation planning and decisions. Furthermore, assessment of specific forestry regulations and biogeographical variation in a number of other countries/provinces embracing boreal and temperate biomes also indicate that natural boundaries are insufficiently considered in forest management policies. We suggest that a substantial potential exists to better align conservation priorities with biogeographical characteristics. To illustrate the application of such an approach, we present a decision support model on how forest conservation policies that rest on natural boundaries and ecological processes can be developed. [ABSTRACT FROM AUTHOR]

The Nkuhlu large-scale long-term exclusion experiment in Kruger National Park was designed to study the long-term effects of large herbivores on vegetation. One treatment excludes elephants, another excludes all herbivores larger than hares and another one comprises an open, control area. Vegetation monitoring was implemented in 2002 when a baseline survey was conducted prior to exclusion. Monitoring was repeated 5 years after exclusion. Data from the surveys were analysed to establish how structure and composition of woody vegetation had changed 5 years after herbivore exclusion. The analysis showed that neither plant assemblage nor mean vegetation height had changed significantly since exclusion. However, both species richness and density of woody plants increased 5 years after exclusion of all large herbivores, but not after the exclusion of elephants alone. One already common species, Dichrostachys cinerea, became more common after excluding all large herbivores compared with either no exclusion or elephant exclusion, possibly leading to competitive suppression of other species. Species other than D. cinerea tended to either increase or decrease in density, but the changes were insufficient to induce significant shifts in the overall assemblage of woody plants. The results indicate that after 5 years of exclusion, the combined assemblage of large herbivores, and not elephants alone, could induce changes in species richness and abundances of woody plants, but the effect was so far insufficient to induce measureable shifts in the assemblages of woody plants. It is possible that assemblages will change with time and increasing elephant numbers may amplify future changes. [ABSTRACT FROM AUTHOR]

The article presents a study regarding the effect of clear-cutting forestry practices on boreal organisms and on saproxylic and non- saproxylic beetle. The study compared group of beetles using three successional phases of boreal spruce forests and evaluated whether saproxylic and non- saproxylic beetle shows biodiversity patterns. The study reveals that not only forest is affected but also the group compositions of beetles and other site aspects such as altitude and management history.

In addition to potential benefits, biotechnology in silviculture may also be associated with environmental considerations, including effects on organisms associated with the living tree and on ecosystems and processes dependent on tree residue. We examined whether genetic modification of lignin characteristics (CAD and COMT) in Populus sp. affected leaf litter quality, the decomposition of leaf litter, and the assemblages of aquatic insects colonizing the litter in three natural streams. The decomposition of leaf litter from one of the genetically modified (GM) lines (CAD) was affected in ways that were comparable over streams and harvest dates. After 84 days in streams, CAD-litter had lost approximately 6.1% less mass than the non-GM litter. Genetic modification also affected the concentration of phenolics and carbon in the litter but this only partially explained the decomposition differences, suggesting that other factors were also involved. Insect community analyses comparing GM and non-GM litter showed no significant differences, and the two GM litters showed differences only in the 84-day litterbags. The total abundance and species richness of insects were also similar on GM and non-GM litter. The results presented here suggest that genetic modifications in trees can influence litter quality and thus have a potential to generate effects that can cross ecosystem boundaries and influence ecosystem processes not directly associated with the tree. Overall, the realized ecological effects of the GM tree varieties used here were nevertheless shown to be relatively small. [ABSTRACT FROM AUTHOR]

In this article the authors comment on the article "Flawed Meta-Analysis of Biodiversity Effects of Forest Management," by P. Halme and colleagues. The authors stress that Halme and colleagues has overlooked the fact that they have discussed the cofounding effects and limitations of meta-analysis (MA). They add that Halme and colleagues have questioned the independence of observation, but generally accepted the comparison of a single control to several experimental groups in the MA process.

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Copyright of Conservation Biology is the property of Wiley-Blackwell 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.)

Plant phenotypes often differ in their resistance to natural enemies, but the mechanism for this has seldom been identified. The aim of this study was to determine if the spatial patterns of phenotype use of a highly specialized insect herbivore (the galling sawfly Pontania triandrae) in a natural willow population can be related to phenotypic variation in plant secondary chemistry. Furthermore, we tested if traits that confer resistance to one type of natural enemy, i.e. the galling sawfly, also confer resistance to others, in our case a leaf beetle Gonioctena linnaeana and the rust fungus Melampsora amygdalinae. We identified 18 phenotypes with high and 18 phenotypes with low gall density in our field population and determined gall densities, the degree of leaf damage and rust infection on each phenotype and collected leaves for chemical analyses. The concentration of phenolics was higher in phenotypes with high density of galls suggesting that this galling sawfly may use phenolics as oviposition cues. Rust infection showed the opposite pattern, with lower levels on clones with high concentration of phenolics, while leaf damage by G. linnaeana did not differ between clone types. This indicates that these important natural enemies may assert divergent selection on willow phenotypes and that this might provide a mechanism for maintaining phenotypic variation within willow populations. [ABSTRACT FROM AUTHOR]

In the original published article, the sentence "Nevertheless, semi-natural forest remnants continue to be harvested and fragmented (Svensson et al. 2018; Jonsson et al. 2019), and over 2000 forest-associated species (of 15 000 assessed) are listed as threatened on Sweden's red-list, largely represented by macro-fungi, beetles, lichens and butterflies (Sandström 2015)."under the section Introduction was incorrect. The correct version of the sentence is "Nevertheless, semi-natural forest remnants continue to be harvested and fragmented (Svensson et al. 2018; Jonsson et al. 2019), and approximately 2000 forest-associated species (of 15 000 assessed) are on Sweden's red-list, largely represented by macro-fungi, beetles, lichens and butterflies (Sandström 2015)." [ABSTRACT FROM AUTHOR]

1 Host–pathogen interactions in isolated populations may result in the adaptation of pathogens to local hosts. However, results of earlier studies of local adaptation in plant–pathogen systems have been contradictory and it has been suggested that specific, species characteristics, for example distribution, dispersal and the degree of pathogen dependence on the host, are important for the outcome of host–pathogen interactions. In addition, the scale of the study may influence whether or not local adaptation is found. 2 We argue that local adaptation of the pathogen to the host can be expected in a system where: (i) the pathogen is host-specific with a short generation time compared with the host; (ii) populations are isolated, allowing localized evolution to occur; and (iii) the study is performed on a geographical scale exceeding the maximum dispersal range of the interacting species. 3 To test these predictions we examined the within- and among-population variation in resistance and virulence of the plant–pathogen system Salix triandra– Melampsora amygdalinae. The pathogen occurs throughout the whole distribution range of the host, and the area of interest consists of highly isolated, small natural populations. 4 Resistance and virulence differed both within and between populations and all clones showed a unique resistance pattern. We conclude that M. amygdalinae is locally adapted to the host S. triandra as all pathogen populations have a higher probability of infecting sympatric than allopatric hosts. Furthermore, high resistance in the host population was accompanied by a high virulence in the pathogen population, suggesting that high resistance levels in a host population may select for more virulent pathogen populations, or vice versa. 5 The nature of host–pathogen interactions differs among systems, and the dynamics of the interaction between S. triandra and M. amygdalinae is governed by characteristics that have resulted in the evolution of local adaptation. 6 Thus, when studying local adaptation of pathogens to their hosts it is important to consider the biology, as well as the scale of dispersal and spatial distribution of both host and pathogen. [ABSTRACT FROM AUTHOR]

Intensive forestry practises in the Swedish landscape have led to the loss and fragmentation of stable old-growth habitats. We investigated relationships between landscape composition at multiple scales and the composition of saproxylic beetle assemblages in nine clear-cut, mature managed and old-growth spruce-dominated forest stands in the central boreal zone of Sweden. We set out fresh spruce and birch logs and created spruce snags in 2001–2002 to experimentally test the effects of coarse woody debris (CWD) type and forest management on the composition of early and late successional, and red-listed saproxylic beetle assemblages. We examined effects of CWD availability at 100 m, and landscape composition at 1 and 10 km on saproxylic beetle abundances. Additionally, we tested whether assemblage similarity decreased with increasing distance between sites. We collected beetles from the experimental logs using eclector and window traps in four periods during 2003. CWD was measured and landscape composition data was obtained from maps of remotely sensed data. The composition of saproxylic beetles differed among different CWD substrates and between clear-cuts and the older stand types, however differences between mature managed and old-growth forests were significant only for red-listed species. Assemblage similarities for red-listed species on clear-cuts were more different at greater distances apart, indicating that they have more localised distributions. CWD availability within 100 m of the study sites was rarely important in determining the abundance of species, suggesting that early successional saproxylic beetles can disperse further than this distance. At a larger scale, a large area of suitable stand types within both 1 and 10 km resulted in greater abundances in the study sites for several common and habitat-specific species. The availability of suitable habitat at scales of 1–10 km is thus likely to be important in the survival of many saproxylic species in forestry-fragmented areas. [ABSTRACT FROM AUTHOR]

To investigate patterns of plant defence, a study was conducted on 13 tree species in Botswana. We tested the hypotheses that (1) shoots on small, young trees are more defended than shoots at the same height on tall, mature individuals and (2) shoots within browsing height are more defended than shoots above the reach of browsers, on mature trees. Plant traits studied were total phenolics, tannin activity, nitrogen (N), acid-detergent fibre (ADF), and degree of spinescence (in three species). We found some support for the first hypothesis. Overall young trees had a significantly higher concentration of total phenolics than mature trees and on species level these differences were significant for three of the 13 species. However, we found no differences in tannin activity, spinescence or ADF concentration between young and mature trees, and four species had higher levels of N in young trees, suggesting higher overall palatability. Contrary to our second hypothesis, shoots within browsing height were less chemically defended (total phenolics and tannin activity) than shoots above browsing height in six of 13 species. Two species had less ADF in lower shoots, and no significant differences were found in N or spinescence for any species. This study included a broad range of tree species at two sites and the results indicate that general theories of plant defence, originating from boreal and northern temperate forests, cannot be simply applied to savanna ecosystems. [ABSTRACT FROM AUTHOR]

In recent years, the influence of plant hybridization on plant–animal interactions has become an important issue; however, these studies have mainly focused on insects or slugs and to a large degree ignored mammalian herbivores despite their importance in many ecosystems. This study aims to determine the preference of voles for pure Salix caprea, S. repens, and their F1, F2, and backcross hybrids to evaluate whether voles select against hybrids in natural willow populations. To address this, we conducted two field studies and a cafeteria experiment in the laboratory with bank voles ( Clethrionomys glareolus). We found no strong indications of reduced resistance in any of the hybrid taxa. Voles damaged more S. repens than S. caprea individuals. There was a general decreasing trend of utilization from pure S. repens to pure S. caprea, hybrid taxa being intermediate between the parents. Thus, voles seemingly do not have a more detrimental effect on hybrid fitness than on the fitness of pure individuals and probably will not select against hybrids in these willows populations. [ABSTRACT FROM AUTHOR]

The biodiversity crisis calls for immediate restoration of deteriorated and rare habitat. Due to fire suppression and intensive forest management, boreal pine forests of high conservation value are exceptionally rare. Despite decades of restoration research in boreal forests, relatively few studies have evaluated multi-taxon biodiversity response of restoration measures in pine forests. In a Scots pine experiment, we investigated biodiversity patterns of wood-inhabiting fungi and beetles a decade after restoration (prescribed burning and deadwood creation) and forest management (harvest with varying retention). We found that fungi and beetles develop differently and have distinct preferences in deadwood originating from restoration. Standing deadwood supported more species for beetles and lying deadwood for fungi and for both taxa, standing and lying deadwood harboured different species assemblages. Burned deadwood displayed less variable assemblages than unburned deadwood for both organism groups. We found that, after a decade, deadwood type and not harvest with different retention levels better explained diversity patterns of wood-inhabiting beetles and fungi in pine forests. Pine forests are naturally prone to recurring disturbances creating open light conditions. Pine-associated species are therefore likely resistant to disturbance as long as a variety of deadwood resources are present. To accommodate multiple taxa, a variety of substrate and environment types is required. Beetles benefit from standing deadwood while fungi benefit from lying deadwood. To support assemblages with both rapid and slow turnover rates, a combination of recurring restoration and leaving restored stands in the adjacent landscapes is required. • Substrate type was more influential than retention level for saproxylic biodiversity. • Logs host more fungal species than snags. • Snags host more beetle species than logs. • Deadwood types hosted different saproxylic assemblages. • Different deadwood types and decay stages are needed to support saproxylic biodiversity. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the responses of herbivores and pathogens to hybrid plants under controlled conditions. F1 hybrids and parental species, produced by hand-pollinating willows in the field, were potted and kept in an experimental field under controlled conditions. In 1997, plant growth and survival were measured along with densities of insects and the degree of pathogen infection on the willows. The survival rate was higher for S. repens than for the hybrids and lowest for S. caprea. Densities of the sawflies Pontania pedunculi and P. brigmanii and the leaf-galling midge Iteomyia capreae were higher on hybrids and on S. caprea than on S. repens. The densities of Crepidodera fulvicornis (Chrysomelidae), chrysomelid larvae and the bud-galling midge Dasineura rosaria did not differ between any of the plant categories. Hybrids were more severely infected by rust ( Melampsora sp.) than S. caprea and the totally resistant S. repens. Densities of herbivores on hybrid willows were consistent with the dominance hypothesis (i.e. herbivore densities were similar to densities on one of the parental species) or supported the no-difference hypothesis. Furthermore, herbivore densities on hybrid plants were most similar to densities on the more susceptible parent. The breakdown in rust resistance in hybrid plants suggests that resistance traits are severely disrupted by the genetic re-arrangement in hybrids and that this increased susceptibility could select against hybridisation. [ABSTRACT FROM AUTHOR]

To test hypotheses of herbivore response to hybrid plants, I determined the preference of the generalist beetle Lochmeae capreae for individuals of Salix caprea, Salix phylicifolia and F1 hybrids between these species. F1 hybrids and pure individuals were created by hand-pollination of willow individuals in the field. The preference tests were performed in 1994 and 1995 and in both years there was a tendency for higher leaf area consumption from hybrids than from the parental species. However, statistically significant differences in consumption were only found in 1995 between hybrids and S. phylicifolia. The result from this study therefore lends most support to the dominance hypothesis: hybrid susceptibility was similar to that of one of the parental species. This is one of the first strict preference tests showing that a generalist herbivore can detect differences in palatability between hybrids and parental species. Furthermore, the experimental design used in the study minimized environmental variation. The results should therefore primarily reflect genetically based quality differences between hybrids and parental species. [ABSTRACT FROM AUTHOR]

To evaluate the general extent to which sex-related differences in palatability occur in boreal dioecious woody plants, males and females of five dioecious woody plant species were presented to free-ranging mountain hares ( Lepus timidus) during winter. Hares strongly preferred branches from male plants when feeding on Populus tremula and Salix caprea and weakly preferred male S. pentandra. However, they did not show any sex-related preference when feeding on the other two species studied ( Myrica gale and Juniperus communis). Nitrogen concentration and, to some degree, digestibility showed strong relationships with hare food preferences. By contrast, the concentration of phenolics was only weakly related to feeding preference. Phenolics could, nevertheless, still be important if only one or a few specific compounds deter hare feeding. These results indicate that sex-related differences in plant palatability in the boreal forest might be more widespread than previously believed, particularly for species of the family Salicaceae. Thus, herbivores might be responsible for the female-biased sex ratios found in willow populations in northern Scandinavia (e.g. Elmqvist et al. 1988). [ABSTRACT FROM AUTHOR]

The rotation forestry system provides high biomass production, but could also have a negative impact on species sensitive to disturbance. Continuous cover forestry (CCF) could contribute to solving these conflicting goals, but its feasibility in nutrient limited boreal forests is yet unresolved. In a unique experiment, we simultaneously assessed the short-term effect of single-tree selection on both biomass production and biodiversity (vascular plants, bryophytes, wood-inhabiting fungi), and tested fertilization as a way to mediate growth-biodiversity trade-offs. We found that unharvested stands and stands subjected to single-tree selection had a similar species assemblage of vascular plants, bryophytes, and wood-inhabiting fungi. Fertilization increased growth by 37% and induced shifts in two understory species (favoring the grass Avenella flexuosa and disfavoring the bryophyte Hylocomium splendens). We conclude that single-tree selection may become a useful tool to enhance biodiversity in managed forests. [ABSTRACT FROM AUTHOR]

Cavities made by birds are an important microhabitat for many taxa in forests. Long-term dynamics of cavity patterns and the effect of forest management on cavities are, however, largely unknown. We studied cavity production, measured as nest cavity production rates (CPR = no. of new cavities/km2/year), of woodpeckers and tits in forests with different management intensity in southern Finland, based on a data from 37 years. Forests were divided into managed, seminatural and natural stands. The data covered 56 forest stands with the total area of 1690 ha. Stands were inventoried annually for new cavities. The total numbers of woodpecker and tit cavities were 2238 and 329, respectively. There were large differences in CPRs between forest stands with different management intensity. For woodpeckers, the CPR was highest in natural forests (5.7) and lowest in managed forests (1.5). For the tit species, the respective numbers were 0.9 and 0.3. The CPRs of different cavity-making bird species and cavity tree characteristics (e.g. tree condition and species) were consistent, suggesting that different cavity-makers benefit from similar forest and tree characteristics. The results also suggest that forests managed with currently prevailing methods limit the production of cavities. To promote cavities, the results from this and other studies suggest that managed forests should include more features of natural forests, such as more diverse tree species and within-stand structural variability distribution (tree-level heterogeneity), larger amount of decayed wood, more retention trees and snags and longer rotation periods. [ABSTRACT FROM AUTHOR]

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]

Topographic heterogeneity causes gradients in altitude, potential solar radiation and soil humidity on a range of scales from micro- to macro-habitat. These gradients are important determinants for the distribution of many organisms but have been largely neglected in studies of species associated with dead wood, a group of great conservation concern. In this study, we evaluated the effects of topography-related gradients (altitude, potential solar radiation and soil humidity) and habitat characteristics (bark cover, ground contact and dead wood volume) on saproxylic (wood-inhabiting) beetle assemblages. We sampled boreal saproxylic beetles hatching from 750 experimentally exposed spruce and birch logs in a regional scale field experiment including 10 landscapes and spanning gradients of altitude (range 85–510 m asl), potential solar radiation (based on slope and slope aspect and highest in equator-facing slopes, PADIR, range 0.24–0.71) and soil humidity (humidity index, range 2.3–3.1). The logs were placed in north Swedish forests and clear-cuts and beetles were sampled with emergence traps the 4th summer after the logs were introduced. Saproxylic assemblage composition varied considerably in response to altitude, potential solar radiation and soil humidity. The response was evident in both forests and clear-cuts and for both birch and spruce logs. Species density and abundance responses differed among trophic groups. For birch logs, fungivore species density increased significantly with increased potential solar radiation. For spruce logs, altitude affected total species density and density of cambium consumers positively and abundance of fungivores negatively, suggesting a delay in succession due to slower decomposition at higher altitudes. In addition to the topography-related gradients, ground contact and bark cover of logs as well as the availability of dead wood in the vicinity influenced the beetle assemblages. Our results clearly show that topography-related gradients affect assemblage composition of saproxylic beetles. These factors should be considered in the management of saproxylic biodiversity. To ensure the safeguarding of intact saproxylic assemblages it is important that the full range of dead wood habitats is conserved. Topographic heterogeneity may provide opportunities for landscape scale survival in response to rapid climate change but there is also a risk that some niches will disappear. Some of the negative effects of climate change could be mitigated by allocating set asides and restoration efforts in areas where gradient in altitude, solar radiation and soil humidity are particularly well developed over short distances. [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]

Abstract: Modern forestry practices have decreased the abundance of coarse woody debris (CWD), and as a result many species that depend on dead wood are now threatened. This implies a need to develop forestry practices that maintain biodiversity. We examined the conservation value of experimental spruce logs (control logs, logs placed in natural shade, and cut tree tops) for wood-inhabiting fungi in two forest stands, one nature reserve and one mature managed forest, in each of seven forest areas in northern Sweden. Here we report the initial findings of the experiment that was established in winter 2001–2002 and data were collected in 2002, 2003 and 2006. A pre-inventory of the local species composition in 2002 revealed a higher per area species richness, including red-listed species, in reserves than in managed forests. Ordination analyses of the experimental logs showed a significant effect of area, while not of stand type in 2003. ANOVA analysis showed no significant effect of stand type on species richness and abundance. In 2006, the species assemblage started to differentiate between the two stand types and forest age, forest site type (moisture), and distance to forest reserves, all explained part of the variation, whereas the amount of CWD, and species composition at the start of the experiment only showed a marginal effect. The early successional fungal community was dominated by two functional groups, humus-decayers and white-rot species, both characterized by a rapid, early colonization and fruit-body formation on the competition-free new substrate. A similar positive response to the new substrate was also observed for the mycorrhizal species in 2006. The high frequency and early appearance of humus-decayers and mycorrhizal species that do not primarily depend upon CWD for their nutrition suggest that their formation of fruiting bodies is limited by substrate availability. Thus some mycorrhizal fungi are apparently rare due to lack of suitable substrate for fruit-body formation. Evidence of dispersal-limitation was observed in 2006. Fomitopsis pinicola, an early colonizer in boreal forests, playing a key role for other wood-inhabiting organisms, colonized significantly more logs in the reserve stands compared with the managed stands. Our data demonstrate that lack of CWD strongly affects both species that depend upon wood for nutrition and species that depend upon wood for fruit-body formation. Thus some species may show an apparent rarity due to lack of suitable substrate. We conclude that creation of CWD appears to be a useful method to maintain or restore fungal diversity in boreal coniferous forests. [Copyright &y& Elsevier]

The multi-scale approach to conserving forest biodiversity has been used in Sweden since the 1980s, a period defined by increased reserve area and conservation actions within production forests. However, two thousand forest-associated species remain on Sweden's red-list, and Sweden's 2020 goals for sustainable forests are not being met. We argue that ongoing changes in the production forest matrix require more consideration, and that multi-scale conservation must be adapted to, and integrated with, production forest development. To make this case, we summarize trends in habitat provision by Sweden's protected and production forests, and the variety of ways silviculture can affect biodiversity. We discuss how different forestry trajectories affect the type and extent of conservation approaches needed to secure biodiversity, and suggest leverage points for aiding the adoption of diversified silviculture. Sweden's long-term experience with multi-scale conservation and intensive forestry provides insights for other countries trying to conserve species within production landscapes. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Translocation of deadwood in ecological compensation: A novel way to compensate for habitat loss." The correction addresses an error in one of the equations presented in the article, specifically related to the calculation of the geometrical form of a truncated cone. The correct version of the equation is provided in the correction notice. The original article has been corrected. The correction notice is authored by Olov Tranberg, Anne-Maarit Hekkala, Ola Lindroos, Therese Löfroth, Mari Jönsson, Jörgen Sjögren, and Joakim Hjältén. [Extracted from the article]

Forestry has markedly changed a large proportion of the world's boreal forests, often with negative effects on biodiversity. As a result, forest restoration is increasingly implemented to counteract the negative effects. However, restoration measures aimed at mimicking natural disturbance regimes could simultaneously increase the risk of unwanted negative effects, such as damage by forest pest species. This study compares the effect of two restoration methods (prescribed burning and gap-cutting), on both biodiversity conservation and pest control, to provide a basis for solutions to this potential conflict., Bark beetles are ideal for studying this conflict, as this group is both species-rich and contains notorious pest species. We conducted a unique, large-scale field experiment in which we compared the effect of two different restoration methods on the abundance, species richness and assemblage composition of bark beetles. In addition, we estimated uncontrolled tree mortality by the number of trees that died post-restoration., Beetles were divided in two groups, primary and secondary, the former with an ability to kill growing trees. Bark beetle diversity did not differ between treatment groups prior to restoration. However, after restoration, assemblage composition and primary bark beetle abundance differed between the treatments. Furthermore, species richness was higher in burned and gap-cut stands compared to reference stands., The number of trees that died post-restoration was highest on burned sites, whereas no difference was found between gap-cut and reference stands. The number of dead trees was correlated with the number of primary beetles., Synthesis and applications. We demonstrate the potential for a conflict between forest restoration for biodiversity conservation and the potential risk for tree mortality caused by forest pests. This is likely to become a problem in many boreal forests; however, our results suggest that this conflict can be moderated by the choice of restoration method. The restoration method gap-cutting had a similar positive impact on bark beetle species richness as compared to the burning method, but did not as burning, increase tree mortality. Thus, in areas where there is an apparent risk for pest outbreaks, our data suggest that gap-cutting should be the chosen method to avoid an unwanted increase in tree mortality at the stand level. [ABSTRACT FROM AUTHOR]

Semi-arid savannas are characterised by alternating wet and dry seasons and large inter-annual rainfall fluctuations that affect plant growth. Carbon-based secondary metabolites (CBSMs) vary inversely with growth and nutrients because of the physiological trade-off between cellular growth and differentiation. We predicted that (1) nutrient concentrations decrease during the wet season, (2) CBSM concentrations increase during the wet season and (3) nutrient concentrations are lowest and CBSM concentrations are highest in the dry season. We measured nitrogen, phosphorus, total polyphenols and condensed tannins in six woody species (including one evergreen) seasonally at the Nkuhlu exclosure, Kruger National Park, South Africa, for three consecutive years, including one ‘wet’ year (above-average rainfall) and two ‘dry’ years (below-average rainfall). Neither N nor P consistently decreased during wet seasons, while CBSMs did not consistently increase. Neither N nor P in the evergreen species was consistently lowest in dry seasons, while CBSMs were not consistently highest in dry seasons. We discuss the inconsistent responses in the context of species-specificity and high inter-annual rainfall variation. We conclude that seasonal variations in N, P and CBSMs in semi-arid savannas cannot be easily generalised because they depend on species and year. [ABSTRACT FROM AUTHOR]

Assessing ecological sustainability involves monitoring of indicators and comparison of their states with performance targets that are deemed sustainable. First, a normative model was developed centered on evidence-based knowledge about (a) forest composition, structure, and function at multiple scales, and (b) performance targets derived by quantifying the habitat amount in naturally dynamic forests, and as required for presence of populations of specialized focal species. Second, we compared the Forest Stewardship Council (FSC) certification standards' ecological indicators from 1998 and 2010 in Sweden to the normative model using a Specific, Measurable, Accurate, Realistic, and Timebound (SMART) indicator approach. Indicator variables and targets for riparian and aquatic ecosystems were clearly under-represented compared to terrestrial ones. FSC's ecological indicators expanded over time from composition and structure towards function, and from finer to coarser spatial scales. However, SMART indicators were few. Moreover, they poorly reflected quantitative evidence-based knowledge, a consequence of the fact that forest certification mirrors the outcome of a complex social negotiation process. [ABSTRACT FROM AUTHOR]

Conservation of biodiversity requires in-depth knowledge of trait-environment interactions to understand the influence the environment has on species assemblages. Saproxylic beetles exhibit a wide range of traits and functions in the forest ecosystems. Understanding their responses to surrounding environment thus improves our capacity to identify habitats that should be restored or protected. We investigated potential interactions between ecological traits in saproxylic beetles (feeding guilds and habitat preferences) and environmental variables (deadwood, type and age of surrounding forest). We sampled beetles from 78 plots containing newly created high stumps of Scots pine and Silver birch in boreal forest landscapes in Sweden for three consecutive years. Using a model based approach, our aim was to explore potential interactions between ecological traits and the surrounding environment at close and distant scale (20 m and 500 m radius). We found that broadleaf-preferring beetle species are positively associated with the local broadleaf-originated deadwood and broadleaf-rich forests in the surrounding landscapes. Conifer-preferring species are positively associated with the local amount of coniferous deadwood and young and old forests in the surrounding landscape. Fungivorous and predatory beetles are positively associated with old forests in the surrounding landscapes. Our results indicate that both local amounts of deadwood and types of forests in the landscape are important in shaping saproxylic beetle communities. We particularly highlight the need to increase deadwood amounts of various qualities in the landscape, exempt older forests from production and to increase broadleaf-rich habitats in order to meet different beetle species' habitat requirements. Trait responses among saproxylic beetles provide insights into the significance of broadleaf forest and dead wood as essential attributes in boreal forest restoration, which helps conservation planning and management in forest landscapes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The amount of carbon stored in deadwood is equivalent to about 8 per cent of the global forest carbon stocks 1 . The decomposition of deadwood is largely governed by climate 2-5 with decomposer groups-such as microorganisms and insects-contributing to variations in the decomposition rates 2,6,7 . At the global scale, the contribution of insects to the decomposition of deadwood and carbon release remains poorly understood 7 . Here we present a field experiment of wood decomposition across 55 forest sites and 6 continents. We find that the deadwood decomposition rates increase with temperature, and the strongest temperature effect is found at high precipitation levels. Precipitation affects the decomposition rates negatively at low temperatures and positively at high temperatures. As a net effect-including the direct consumption by insects and indirect effects through interactions with microorganisms-insects accelerate the decomposition in tropical forests (3.9% median mass loss per year). In temperate and boreal forests, we find weak positive and negative effects with a median mass loss of 0.9 per cent and -0.1 per cent per year, respectively. Furthermore, we apply the experimentally derived decomposition function to a global map of deadwood carbon synthesized from empirical and remote-sensing data, obtaining an estimate of 10.9 ± 3.2 petagram of carbon per year released from deadwood globally, with 93 per cent originating from tropical forests. Globally, the net effect of insects may account for 29 per cent of the carbon flux from deadwood, which suggests a functional importance of insects in the decomposition of deadwood and the carbon cycle., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Uneven-aged silviculture may better maintain species assemblages associated with old-growth forests than clear felling in part due to habitat heterogeneity created by maintaining standing retention strips adjacent to harvest trails. Retention strips and harvest trails created at the time of tree removal will likely have different microclimate and may harbor different assemblages. In some cases, the resultant stand heterogeneity associated with uneven-aged silviculture may be similar to natural small-scale disturbances. For beetles, increased light and temperature as well as potential access to young vegetation and deadwood substrates present in harvset trails may harbor beetle assemblages similar to those found in natural gaps. We sampled saproxylic beetles using flight intercept traps placed in harvest corridors and retention strips in 9 replicated uneven-aged spruce stands in central Sweden. We compared abundance, species richness and composition between harvest corridors and retention strips using generalized linear models, rarefaction, permutational multivariate analysis of variance and indicator species analysis. Canopy openness doubled, mean temperature and variability in daily temperature increased and humidity decreased on harvest trails. Beetle richness and abundance were greater in harvests trails than in retention strips and the beetle species composition differed significantly between habitats. Twenty-five species were associated with harvest trails, including three old-growth specialists such as Agathidium discoideum (Erichson), currently red-listed. We observed only one species, Xylechinus pilosus (Ratzeburg) that strongly favored retention strips. Harvest trails foster both open habitat species and old-growth species while retention strips harbored forest interior specialists. The combination of closed canopy, stratified forest in the retention strips and gap-like conditions on the harvest trails thus increases overall species richness and maintains more diverse assemblages at the stand level than would otherwise be seen in less heterogeneous stand types. This suggests that uneven-aged silviculture may provide added conservation benefits for both open habitat and old-growth specialists than silvicultural approaches that reduce stand heterogeneity., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Carbon-based secondary metabolites (CBSMs) are assumed to function as defences that contribute to herbivore-avoidance strategies of woody plants. Severe browsing has been reported to reduce concentrations of CBSMs and increase N concentrations in individual plants, causing heavily browsed plants to be characterised by N-rich/C-poor tissues. We hypothesised that concentrations of condensed tannins (CT) and total polyphenols (TP) should decrease, or N increase, in relation to increasing intensity of browsing, rendering severely browsed plants potentially more palatable (increased N:CT) and less N-limited (increased N:P) than lightly browsed ones. We sampled naturally browsed trees (taller than 2 m) of four abundant species in southern Kruger National Park, South Africa. Species-specific relationships between N:CT, CT, TP and P concentrations and increasing browsing intensity were detected, but N and N:P were consistently invariable. We developed a conceptual post-hoc model to explain diverse species-specific CBSM responses on the basis of relative allocation of C to total C-based defence traits (e.g. spines/thorns, tough/evergreen leaves, phenolic compounds). The model suggests that species with low allocation of C to C-based defence traits become C-limited (potentially more palatable) at higher browsing intensity than species with high allocation of C to C-based defences. The model also suggests that when N availability is high, plants become C-limited at higher browsing intensity than when N availability is low.

Low molecular weight phenolics are suggested to have a role in mediating diet selection in mammalian herbivores. However, very little is known about low molecular weight phenolic profiles of African savanna woody species. We determined low molecular weight phenolic profiles of six woody species with different life history, morphological and functional traits. We investigated interspecific phytochemical variation between species and found that: (1) related Acacia species were chemically dissimilar; (2) similarity percentage analysis revealed that Acacia grandicornuta was most dissimilar from other species and that the evergreen and unpalatable Euclea divinorum had a qualitatively similar chemical profile to the deciduous and palatable Acacia exuvialis and Combretum apiculatum; (3) C. apiculatum had the highest chemical diversity; (4) relative to spineless plants, spinescent plants contained significantly less HPLC phenolics and condensed tannins; and (5) the major quantitative difference between the evergreen and unpalatable E. divinorum and other species was its high myricitrin concentration., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Puumala virus (PUUV), genus hantavirus, causes nephropathia epidemica, a mild form of hemorrhagic fever with renal syndrome in humans. In this study, bank voles, the natural reservoir of PUUV, were captured at locations of previous human PUUV exposure and paired controls within a region of high incidence in northern Sweden. The aim of the study was to evaluate the influence of environmental factors on the abundance of bank voles and the occurrence of PUUV. The total number of voles and the number of PUUV-infected voles did not differ between locations of previous human PUUV exposure and paired controls. The number of bank voles expressing antibodies to PUUV infection increased linearly with total bank vole abundance implying density independent transmission. Using principal component and partial correlation analysis, we found that particular environmental characteristics associated with old-growth moist forests (i.e., those dominated by Alectoria spp., Picea abies, fallen wood, and Vaccinium myrtillus) were also associated with increased abundance of bank vole and hence the number of PUUV-infected bank voles, whereas there were no correlations with factors associated with dry environments (i.e., Pinus sylvestris and V. vitis-idea). This suggests that circulation and persistence of PUUV within bank vole populations was influenced by habitat factors. Future modeling of risk of exposure to hantavirus and transmission of PUUV within vole populations should include the influence of these factors.