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Highlights • Three-toed woodpecker and Siberian jay are important biodiversity indicators. • Prescribed burning changed indicator values of biodiversity indicators. • Biodiversity indicators indicate high species richness and structural complexity. • We must be careful with using previous identified indicator species in ecosystems subjected to ecological restoration. Abstract A wide range of different biodiversity indicators have been identified in different biomes and types of environments. However, we currently lack a clear understanding under which circumstances proposed biodiversity indicators are valid indicators and when they are not. Here we conducted a large-scale restoration experiment by emulating natural disturbances through prescribed burning and gap-cutting. From this experiment data of resident forest birds was used to, (1) identify biodiversity indicators in the middle and northern boreal zone, (2) test the effect of forest restoration practices on biodiversity indicators and (3) explore the patterns when biodiversity indicator analyses are performed across a wider range of forest types including both restored and unrestored sites. Additionally, to understand the occurrence of species we correlated their occurrence with local habitat structures across different forest types. We found that both the three-toed woodpecker (Picoides tridactylus) and Siberian jay (Perisoreus infaustus) were important biodiversity indicators for the middle/northern boreal zone. The occurrence of these species can generally be used to identify species rich areas across different forest types. However, the three-toed woodpecker, the best indicator for unrestored forest, lost its indicator value after prescribed burning; in these stands the goldcrest (Regulus regulus) was the best biodiversity indicator. Based on habitat associations, we suggest that biodiversity indicators in boreal forest not only indicate high species richness but also structural habitat complexity. Our results draw attention to the fact that one must be careful about using previously identified biodiversity indicators in ecosystems subjected to ecological restoration. [ABSTRACT FROM AUTHOR]

In many parts of the boreal biome intensive forest management has resulted in profound changes in forest structure, tree species composition and dead wood availability, and by so negatively effecting forest biodiversity. Restoration of degraded forest habitats is therefore of high priority, both internationally and nationally. Consequently, it is of uttermost importance to develop cost-efficient restoration methods. We have therefore initiated a cost neutral ecological restoration experiment aimed at increasing the variety and volume of dead wood in voluntary set-asides (as part of the FSC certification requirements) by mimicking the two natural disturbances, forest fire and small scale gap dynamics. We studied how tree species and substrate type, i.e. the way in which a tree was killed (cut, girdled, tipped over or cut to produce a high stump), affect species composition, abundance and species richness of saproxylic beetles. We found that species composition differed between tree species in burned as well as gap-cut stands, and that tree posture, i.e. standing or downed trees, also affected species composition in gap-cut stands. In addition, abundance and species richness differed between tree species in gap-cut stands, generally being higher in spruce than in pine and birch. Based on our results we recommend a wider practice of dead wood creation involving a multitude of tree species and tree postures, through mimicking natural disturbances in the management of boreal forests. Furthermore, we suggest that voluntary set-asides provide an excellent opportunity for restoration as they are wide spread and already available in the forest landscape. Restoration cost can therefore be kept at a minimum or totally avoided as in this study. [ABSTRACT FROM AUTHOR]

Large scale use of even-aged silviculture (clear-cutting) commencing in the mid-20th century has had negative impacts on forest biodiversity. As a consequence, uneven-aged silviculture is currently being considered to help meet the ecological and social criteria required for sustainable forest management. Uneven-aged silviculture (e.g. selective felling) involves selective removal of some older trees in a stand which may to some extent mimics natural small scale stand dynamics and thus potentially benefit species associated with old forests. Here we test whether selective felling benefits beetle biodiversity by producing beetle assemblages that better resemble those of old growth stands than those found in uncut production stands. We conducted a field study in northern Sweden, comparing beetles assemblages collected with window traps in three spruce dominated stand types: (1) Stands recently (on average 7 years prior to the study) subjected to selective felling ( Selective felling ), (2) mature uneven-aged stands without recent history of management, resembling selective felling stands prior to management ( Uncut ), and (3) old-growth stands with high conservation values ( Old growth ). As predicted, we found that assemblage composition was similar in selective felling and old growth stands, and that assemblages of cambivores and obligate saproxylics (marginally significant) differed between these two stand types and uncut stands. The differences were largely explained by a higher abundance of saproxylic species presumably associated with old growth conditions and large volumes of deadwood. Thus, although overall assemblage composition did not differ between stand types, part of the beetle community seemingly benefited from selective felling. We therefore recommend that selective felling is considered as an alternative to clear-felling to maintain biodiversity values. [ABSTRACT FROM AUTHOR]

Ecological restoration is increasingly recognised as a useful tool for biodiversity conservation in boreal forests. Most restoration methods in this environment aim to emulate natural disturbances, and thereby promote the development of key ecological structures. However, research about forest ecosystem restoration is still in its infancy and the responses of many boreal species groups remain to be described. We established a large-scale field experiment to evaluate the short-term effects of two restoration treatments – prescribed burning and gap cutting involving the creation of dead wood – on breeding bird assemblages in boreal Sweden. We censused breeding birds using territory mapping during two years in forest stands subjected to the two restoration treatments, in untreated controls and in old-growth references (nature reserves) (n = 10 per treatment). Averaged over the two census years, we found 1145 territories of 36 bird species. Total bird species richness and abundance did not differ among treatments. However, prescribed burning led to clear changes in the structure of the bird assemblages. When dividing species according to four functional categorizations (migration, foraging, nesting and successional stage), we found that the abundance of long-distance migrants, ground breeders, strong cavity excavators and species preferring early-successional habitat was higher in burned stands than in untreated controls and gap-cut stands, as was the species richness of bark feeders and strong cavity excavators. In contrast, abundance of off-ground breeders and species richness of crown feeders were lower following prescribed burning than in the controls. The gap cutting treatment did not have any significant effects on the bird assemblages. Ecological restoration through prescribed burning can be a useful tool for the conservation of boreal forest birds, including the ecologically important strong cavity excavators (i.e. woodpeckers (Picidae)). Forest managers should therefore be encouraged to use prescribed burning as a restoration tool to quickly provide habitat for bird species adapted to natural disturbances in boreal forest. [ABSTRACT FROM AUTHOR]

Decline in biodiversity have increased the interest in alternative forest management approaches. Uneven-aged silviculture has been proposed as a mean to maintain continuity of forest canopy cover, mimic small-scale disturbances and provide a stratified forest structure similar to that of old-growth forests and therefore better maintain species associated with unmanaged forest. We used a large-scale chronosequence study spanning 50 years to study beetle diversity in uneven-aged silviculture compared with both short-term impacts and the longer-term legacy of even-aged silviculture. We compared: (1) even-aged recently clear-felled stand, (2) even-aged recently thinned stand, (3) uneven-aged stands subjected to selective felling with (4) uneven-aged reference stands to evaluate whether abundance, species richness and composition of beetles (Coleoptera) were affected differently by even-aged than by uneven-aged management. We collected 15,147 beetles from 461 species using flight interception traps in 30 stands. Beetle composition was maintained in uneven-aged managed stands; composition did not differ from unmanaged reference stands, the exception being cambium consumers. Both even-aged silviculture treatments (clear-felling and thinning) had different beetle composition compared to the reference stands, indicating that assemblages had yet to recover even 50 years into the rotation. However, beetle composition did not differ between uneven-aged managed and thinned stands. The result supports our prediction that uneven-aged silviculture better maintains beetles assemblages associated with semi-natural mature forest than even-aged silviculture. The greater temporal continuity in selectively felled stands could benefit species dependent of mature or old growth forest since some of the needed habitat qualities are continuously available. Uneven-aged silviculture could therefore serve as an important tool for landscape planning to benefit biodiversity and thus help fulfil environmental commitments. However, uneven-aged silviculture may still alter the forest and should therefore be viewed as an alternative to even-aged silviculture, rather than to set-asides. [ABSTRACT FROM AUTHOR]

Stumps comprise up to 80% of the residual deadwood following clear cutting and are a significant source of biomass for bioenergetic applications. However, stump harvesting may pose significant conservation risks for saproxylic organisms that occur in residual deadwood. To define retention targets for stump harvesting operations, we compared abundance and species richness of saproxylic beetles within individual stumps as well as species accumulation curves in replicated pairs of clear cuts with and without stump harvesting in northern Sweden. Using 20 stands, we sampled 1049 stumps using eclector traps and collected 9821 beetles representing 253 species with known saproxylic biology. Nineteen of these species were red-listed in Sweden. We hypothesized that individual stumps left following stump harvesting would contain higher densities and species richness than in clear cuts without stump removal due to crowding of beetles into increasingly limited habitats. However, we found no difference in density or richness within individual stumps between control clear cuts and stumped stands. We also compared species richness between control and stumped treatments using rarefaction within individual stands and across all stands and found no difference. As with density and richness, beetle composition at the stand-level did not differ between control and stumped stands. Thus, the density of surrounding stumps within a stand had very little effect on beetle assemblages in residual stumps. We estimated the effect of stump harvest on species richness at the stand level by combining all samples and extrapolating a rarefaction curve derived from the landscape-level species pool to an accumulated sample volume of 48 m 3 which corresponds to the total volume of stumps on average-sized clear cuts in Northern Sweden. Using this curve, we compared differences in species richness in average-sized clear cuts with 100% (48 m 3 ) and 25% (12 m 3 ) stump retention and found that stump harvest resulted in a 26% (95% C.I. 7–41%) loss of species. While the absolute scaling of the landscape-derived rarefaction does not reflect species loss at the stand-level because the combined curve reflects all rare species in the landscape, the relative species loss derived from this curve may serve as credible benchmark for species loss at the stand level following current stump harvesting practices. This benchmark may be further calibrated with additional information on number of singleton species and estimates of maximum species richness. [ABSTRACT FROM AUTHOR]

Management of boreal forests for timber production has caused changes in forest structures and disturbance regimes, which have influenced a wide range of organisms. The aim of this study was to evaluate how composition of epigaeic (ground-living) beetle assemblages is influenced by stand age and management history in a heavily managed boreal forest landscape. We compared the epigaeic assemblages among stands of three ages: (1) young (8–25 years) and (2) middle-aged (40–58 years) stands regrown after clear-cutting, and mature stands (80–130 years) that had been selectively cut historically but never clear felled. We sampled epigaeic beetles in each of 42 stands, using 10 pitfall traps during seven summer weeks. More than 9000 specimens were collected and identified. The assemblages in young stands differed from those in middle-aged and mature stands, both for the Staphylinidae (rove beetles) and all beetle families combined. Carabidae (ground beetles) composition differed between young and middle aged stands only, and assemblages of Curculionidae (weevils, bark beetles and allies) differed between young and mature stands only. Assemblages of Leiodidae (round fungus beetles) had similar composition in all three stand types. Considering all families, young stands generally harbored fewer species and lower abundances compared with middle aged and mature stands. However, the Leiodidae had similar species richness in all three stand types. The lack of differences in assemblage composition, species richness and abundance between middle aged and mature stands suggests that epigaeic beetle assemblages recolonize following clear-felling. However, our collections included large numbers of unique and usually rare species in mature stands, indicating that old forest is important for the conservation of epigaeic beetles. Furthermore, the lower abundance of these beetles in young stands indicates that an increasing proportion of young stands on managed landscapes will reduce the overall abundances of epigaeic beetle species, with potentially negative impacts on recolonization. [ABSTRACT FROM AUTHOR]

Highlights: [•] We review environmental considerations in forestry with Sweden as a case study. [•] Environmental considerations in forestry have support in the scientific literature. [•] Retention levels in Sweden are low compared with ecological thresholds. [•] There is a need to better adjust the levels above thresholds from empirical studies. [•] The allocation of consideration in and among landscapes needs to be improved. [ABSTRACT FROM AUTHOR]

Abstract: Intensive forest management has dramatically reduced the area of old-growth forest in Fennoscandia. We examined if the proportion of old forest in a landscape affects species composition, richness and abundance of saproxylic beetles. We used tube-shaped window traps in five pairs of sites, selected so that the sites within each pair differed with respect to the proportion of old forest (>125years) in the surrounding landscape. A landscape level inventory of the wood fungi Fomitopsis rosea, as a proxy for forest with high conservation values, was used to complement the data on old forests. In addition, to testing whether mycelia-colonised wood may attract saproxylic beetles, the tube-shaped window traps were baited with wood colonised by Fomitopsis pinicola or F. rosea. Old-forest-rich landscapes supported significantly more species and a higher abundance of saproxylic beetles than old-forest-poor landscapes. The analysis revealed a clear connection between the community composition of saproxylic beetles and the proportion of old forest and number of F. rosea fruiting bodies in the surrounding landscape (radius 3km). The local landscape species pool thus appears to be important for the beetle species that are trapped since the composition of saproxylic beetles differed between the two landscape types. The effects of the different baits were less pronounced than the effect of landscape type, although species-specific responses to the two mycelia baits were observed. This indicates that volatiles from mycelia of wood-decaying fungi and the mycelial community may affect colonisation patterns of saproxylic beetles. Our results suggest that forest fragmentation and habitat loss have resulted in depauperate beetle faunas in old-forest-poor landscapes. Our results highlight the need to invoke a landscape scale approach for preserving biodiversity, in this case the need to maintain a sufficient proportion of forest with old growth characteristics in the managed landscape. [Copyright &y& Elsevier]

Abstract: Tolerance is along with resistance the two most basic mechanisms used by trees to mitigate damage by herbivores and together they comprise important traits in plant material used in forestry. Genetic modification of trees has targeted various traits including resistance with promising results. Nevertheless, little is still known of how changes of the plant genome may interact with damage to affect tolerance and productivity of the trees. To address this we tested tolerance and growth responses of two different populus hybrids and their corresponding GM varieties to simulated leaf damage and harvest. Morphological growth responses to leaf damage included a decreased biomass production of the effected shoot (e.g. the main stem) which was partly compensated for increased biomass production in the undamaged branches. This compensation was mainly due to growth responses in already existing branches rather than stimulation of new buds. However, despite growth inductions in branches the net growth response seen over the whole plant was negative, e.g. plants could not fully compensate for lost leaf tissue and thus showed under-compensation for damage. We further show that the ability for post harvest re-growth correlated positively with the biomass of plants at harvest but only for the high damage treatment and not for low to intermediate levels of damage under which this relationship was neutral. Tolerance may thus have intricate influence over the success of short rotation plantation practices under which plants are subjected to repeated harvests while simultaneously being subjected to increased risk of severe leaf damage by herbivores. The ability for tolerance did not differ significantly between the two tested hybrids or among hybrids and their corresponding GM varieties. This was also so for the capacity for re-growth after harvest. The production of stem wood and leaves as well as total biomass was, however, significantly different among lines. These among line differences were both caused by differences between the two Wt hybrids (e.g. Wt-Lignin produced ∼37% more biomass than Wt-Bt) and differences caused by genetic modification (e.g. Wt-Bt produced ∼19% more biomass compared to Bt27). Our results give a strong indication that the growth responses of the GM varieties to leaf damage and harvest were substantially equivalent with their corresponding non-GM varieties. These similarities predict that the effect of damage on production should be alike regardless of if the GM or non-GM products are used. [Copyright &y& Elsevier]

Abstract: Studies on the effects of stump harvesting on forest biodiversity are scarce and studies on long-term effects are until now non-existent. We evaluated such long-term effects by sampling beetles at 14 clear-cuts with and 14 clear-cuts without stump harvesting; harvesting had been done 21–28years before this study. By using window traps, we collected 6429 individuals belonging to 432 species in 55 taxonomic families. To control for potentially confounding effects of among-site variations in landscape setting we also assessed forest age and volume of deciduous trees within the forest surrounding each site. The long-term effects from harvesting on beetle abundance, species richness and species composition was generally small in comparison to the influence of the characteristics of the surrounding forests. The species richness of the beetle family Latridiidae and the functional group fungivores appeared, however, to be negatively affected by the previous stump harvesting, while several other groups showed strong associations to the characteristics of the surrounding forest. We found little support for considerable long-term effects of stump harvesting on beetles flying in the stands. Long-term effects of stump harvesting at the landscape scale accumulated from harvest of many localities may still be severe, and should be the subject of future studies. [Copyright &y& Elsevier]

Abstract: The intent with insect-resistant transgenic trees is to increase yield without adverse negative effects on non-target organisms. Thus, the assessment of these products is dependent on not only performance, but also on environmental effects realized in the field. With this study we transition from greenhouse evaluations to assessments under semi-natural field conditions with the objectives: (i) to assess the realized benefits (biomass production and resistance effectiveness) and (ii) to evaluate effects on the biotic interactions of two isogenic transgenic Bt (Bacillus thuringiensis, cry3Aa targeting coleopteran leaf beetles)-expressing aspens. We established an experiment with a total of 108 potted aspen plants (n =36 for three different lines) in the field and applied an additional experimental nutrient treatment to reflect the effects of one aspect of environmental variability. Overall leaf damage was shown to be higher on the un-modified wild type (Wt) plants compared to plants from the high expression line (P =0.003), and the same trend was also detected for the low expression line (P =0.089). However, despite this advantage in resistance, biomass production was not significantly enhanced in insect-resistant plants. Also, whereas the high nutrient treatment showed an increase in biomass, it did not affect the amount of leaf damage inflicted on the plants. Presence/absence surveys of biotic interactions during the study showed that the number of plants that were scored for the presence of three insect orders and two leaf modifications was equal regardless of line treatment. Interestingly, one species included in the presumably targeted order, the leaf rolling beetle Byctiscus populi (Coleoptera) inflicted the insect-resistant plants with oviposition and feeding damage to a similar degree as the un-modified Wt plants. [Copyright &y& Elsevier]

Abstract: 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 &y& Elsevier]

Abstract: The aim of this study was to evaluate how future harvesting of spruce low stumps as a renewable energy source, might influence the saproxylic (wood living) beetle fauna. Species richness, abundance and assemblages of saproxylic beetles were compared on low stumps, high stumps and logs of spruce on 10 clear-cuts in northern Sweden. The sampling was conducted with emergence traps and a total of 929 individuals and 120 species were collected. No significant differences in beetle abundance or species richness were detected between substrate types. However, there were clear differences in assemblage composition between all substrate types. Our results suggest that low stumps created at final felling support as many species and individuals per volume dead wood as other dead wood substrates and that they are therefore overlooked as substrates for wood living organisms. Consequently, harvesting of low stumps might have negative effects on the diversity of saproxylic beetles, as up to 80% of the dead wood remaining on clear-cuts is in the form of low stumps. Future studies should evaluate if compensatory measures can be performed to minimize negative impacts. [ABSTRACT FROM AUTHOR]

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Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag 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.)

Abstract: Predatory beetles are important natural enemies of early successional cambium feeding beetles and knowledge about their ecology is of paramount importance for biological control and sustainable forest management. We used a large-scale experiment including 3 stand types (clear-cut, mature managed and old-growth stand) and 6 dead wood substrates (burned, shaded, white rot inoculated, brown rot inoculated, untreated control logs and created snags) to test substrate preferences of 10 common predatory beetle species. We collected insects in eclector traps and measured dead wood availability within 100m from the experimental logs at each site. We also tested the relationships between predators and prey at the trap level. Stand type was important for all predators; Nudobius lentus and Ampedus tristis were more abundant on clear-cuts while Phloeonomus sjoebergi, Quedius plagiatus, Epuraea boreella, Epuraea pygmaea, Epuraea angustula, Rhizophagus dispar and Epuraea laeviscula were more abundant in mature managed and old-growth stands. Snags differed most from the control logs supporting significantly more E. boreella and E. angustula and significantly less P. sjoebergi, E. pygmaea, A. tristis and R. dispar. Prey abundance proved to be more important than dead wood availability at the stand level for most species, although the response varied among species. At the trap level, the abundances of P. sjoebergi, E. laeviscula and Q. plagiatus were correlated with the abundances of their known prey species. P. sjoebergi, E. boreella, E. pygmaea, R. dispar and N. lentus were correlated with total bark beetle abundance suggesting that many predators might be less specific in their choice of prey than previously thought. The variable response of the 10 examined predatory beetles at different levels of scale suggests complex relationships with their prey and environment. The conservation of this group of beetles is important both to achieve environmental goals but also for biological control of potential pest species. Thus, conservation oriented measures needs to be performed aiming at improving both substrate and stand qualities. [Copyright &y& Elsevier]

Abstract: Different functional groups of beetles are likely to exhibit different responses to forest management and it is essential that we gain knowledge on these responses to understand and minimize the negative impacts of forestry in boreal ecosystems. In a large-scale manipulative experiment in nine sites (including 27 stands) in northern Sweden, we tested how saproxylic beetles, fire-favoured beetles and functional groups of beetles were affected by log treatment (shaded, burnt and fungi inoculated logs) and stand type (clear-cuts, mature managed and old-growth stands). All sites included one clear-cut, one mature managed stand and one old-growth stand, which give in total 27 stands. Fresh logs were placed out in the stands and exposed to different treatments. Insects were caught in eclector traps attached to the experimental logs. Log treatment, stand type and their interactions affected abundance, species richness and assemblages of saproxylic beetles, fire-favoured beetles and functional groups of beetles. Cambium consumers were less abundant on burnt logs compared with control logs. Furthermore, the assemblage composition differed between burnt logs and control logs for fire-favoured species and cambium consumers. On the clear-cuts burnt logs hosted lower abundance of all saproxylic beetles and fire-favoured species. For predators, the assemblage composition differed between burnt logs and control logs on clear-cuts. Shaded logs hosted lower abundance of wood borers compared to control logs. Shaded logs also supported different assemblages of saproxylic beetles and predators compared with the control logs on clear cuts. The effect of stand type was stronger than the effect of log treatment and for most of the examined groups; the clear-cuts differed from the mature managed and old-growth stands, while few differences was detected between mature managed and old-growth stands. The results indicate that in an area with intense forestry, both old-growth forest reserves and the creation of suitable substrates in managed forests are needed to conserve functionally intact beetle assemblages. [Copyright &y& Elsevier]

Abstract: Many saproxylic beetles do not feed on wood directly but on fungi colonizing the wood. The volume of decaying wood has decreased drastically in Scandinavian managed forest landscapes in recent years, so improved knowledge on the interactions between beetles and wood-decaying fungi is important for the long-term persistence of these trophic partners. Sporocarps of polypores are known to emit volatiles attracting both fungivorous and predatory beetles, but it is unknown whether some beetles are also attracted to odours from the mycelia. The aim of this experiment was to test the attraction of beetles to volatiles from the sporocarps and mycelia of wood-decaying fungi. In a randomized block design, six substrate types: Fomitopsis pinicola sporocarp, F. pinicola mycelium-infected wood, Fomitopsis rosea sporocarp, F. rosea mycelium-infected wood, Phellinus chrysoloma sporocarp and Phlebia centrifuga mycelium-infected wood were attached separately to specially designed window traps in four old-growth spruce forests in northern Sweden. Empty traps and traps with sterilised wood were used as controls. We found no significant differences in the species richness or abundance of saproxylic beetles between the control and sterilised wood and the fungal substrates. However, two abundant species showed significant preferences for one substrate type. The bark beetle Dryocoetes autographus preferred F. rosea mycelium-infected wood and the rove beetle Lordithon lunulatus preferred fruiting bodies of F. pinicola. The results indicate that some species do discriminate between volatiles emitted by different polypore species and also between volatiles emitted by the sporocarps and mycelia from the same species. Our data indicate a hitherto unknown interdependence between D. autographus and F. rosea. We conclude that present knowledge on interactions between beetles and wood-decaying fungi is limited and further studies are needed to enhance our ability to design appropriate conservation strategies in the forest landscape. [Copyright &y& Elsevier]

Direct seeding of Pinus sylvestris (L.) is a regeneration method of increasing popularity due to its comparatively low cost and potential for mechanisation. There is, however, a concern that seed losses to predators may jeopardise some seeding operations and means of reducing losses are therefore sought. In a study in northern Sweden, we studied the effect of covering seeds with a thin layer of the substrate on which the seeds were sown immediately after seeding. This lowered seed-predation from 9.1 to 2.9% and total seed losses from 64 to 45%. More seeds, 40% compared to 27%, failed to germinate when covered. At the end of the first growing season, 15.4% of the initially covered seeds were present as live seedlings compared to 9.2% of the seeds in the uncovered control treatment. However, although the trend remained the same, this effect was no longer significant after the first winter. The seedlings from the covered seeds were significantly larger, even after the second growing season. A complementary laboratory experiment showed that bank-voles, Clethrionomys glareolus, consumed significantly more seeds on the soil surface compared to covered seeds, but that they could find covered seeds with relative ease. We conclude that covering seeds immediately after seeding is a cost-effective way to reduce seed-predation and increase seedling emergence. [Copyright &y& Elsevier]

• Forest management has promoted conifers and altered stream and riparian function. • We suggest delineating and managing riparian buffers throughout the rotation cycle. • Make multi-layered, mixed-species forests with more deciduous species the goal. • Riparian zones will provide functions throughout the rotation, not just at final-felling. Riparian buffers are the primary tool in forest management for protecting the habitat structure and function of streams. They help protect against biogeochemical perturbation, filter sediments and nutrients, prevent erosion, contribute food to aquatic organisms, regulate light and hence water temperature, contribute deadwood, and preserve biodiversity. However, in production forests of Sweden and Finland, many headwater streams have been straightened, ditched, and/or channelized, resulting in altered hydrology and reduced natural disturbance by floods, which in turn affects important riparian functions. Furthermore, in even-aged management systems as practiced in much of Fennoscandia, understory trees have usually been cleared right up to the stream's edge during thinning operations, especially around small, headwater streams. Fire suppression has further favored succession towards shade tolerant species. In the regions within Fennoscandia that have experienced this combination of intensive management and lack of natural disturbance, riparian zones are now dominated by single-storied, native Norway spruce. When the adjacent forest is cut, thin (5 - 15m) conifer-dominated riparian buffers are typically left. These buffers do not provide the protection and subsidies, in terms of leaf litter quality, needed to maintain water quality or support riparian or aquatic biodiversity. Based on a literature review, we found compelling evidence that the ecological benefits of multi-layered, mixed-species riparian forest with a large component of broadleaved species are higher than what is now commonly found in the managed stands of Fennoscandia. To improve the functionality of riparian zones, and hence the protection of streams in managed forest landscapes, we present some basic principles that could be used to enhance the ecological function of these interfaces. These management actions should be prioritized on streams and streamside stands that have been affected by simplification either through forest management or hydrological modification. Key to these principles is the planning and managing of buffer zones as early as possible in the rotation to ensure improved function throughout the rotation cycle and not only at final felling. This is well in line with EU and national legislation which can be interpreted as requiring landscape planning at all forest ages to meet biodiversity and other environmental goals. However, it is still rare that planning for conservation is done other than at the final felling stage. Implementing this new strategy is likely to have long-term positive effects and improve the protection of surface waters from negative forestry effects and a history of fire suppression. By following these suggested management principles, there will be a longer time period with high function and greater future management flexibility in addition to the benefits provided by leaving riparian buffers at the final felling stage. [ABSTRACT FROM AUTHOR]

• Boreal forest clear-cutting change species composition of mosses and liverworts. • After half a century both cover and occupancy are changed in 1-ha secondary stands. • Species thriving in shade and on living or dead trees are still fewer. • Current habitat factors explain much of the remaining differences. • Species losses can be mitigated by providing shade and tree substrates. A growing proportion of the boreal biome consists of managed even-aged secondary forest stands regenerated after clear-cutting. Many disturbance-intolerant species may not be able to recolonize or reach their original abundance in these stands before the next clear-cutting, potentially causing large-scale biodiversity losses. Boreal bryophytes (mosses and liverworts) include many species intolerant to clear-cutting, and at small spatial scales species richness and occupancy has been shown to remain changed in secondary stands half a century after logging. To assess if such persistent changes occur also at the stand scale, we listed and estimated cover of all bryophyte species in 1-ha plots, comparing 14 secondary stands originating from clear-cutting 40–60 years earlier with 14 older semi-natural stands. The large plots also made it possible to assess differences in occupancy and abundance for more bryophyte species than in previous studies. Species composition differed significantly for both mosses and liverworts, but unlike earlier studies, we could not detect any significant difference between stand types in species numbers. Thirteen species were significantly associated with semi-natural stands and the total cover of liverworts was less than half in secondary stands. Secondary stands had significantly fewer species typically occurring under shady conditions and/or mostly growing on "tree substrates" (dead wood and/or bases and stems of living trees). Ordination analysis further emphasized the importance of shade and suitable deadwood substrates; the among-plot variation in bryophyte species composition was related to amount of coarse deadwood as well as to gradients from shady spruce dominated to open pine dominated stands and from polar- to equator-facing slopes. Besides lack of suitable habitat conditions in secondary stands, dispersal limitation may have caused a colonization time lag for some species. The clear importance of stand scale habitat conditions for bryophyte species composition calls for management adaptions to facilitate life boating and/or recolonization by ensuring availability of shade, coarse decomposing logs, and specific deciduous tree species (Populus , Salix , Sorbus) in secondary stands. [ABSTRACT FROM AUTHOR]

• Even-aged silviculture (thinning) vs uneven-aged silviculture (selective felling) • Species richness did not differ between management type. • Thinned stands supported different bird assemblages than selectively felled stands. • Independent of management type, time since treatment effect assemblage structures. Biodiversity is in decline and therefore alternative forest management approaches have gained interest. One of such approaches is uneven-aged silviculture, which has been suggested to better maintain mature or late-successional forest characteristics and species assemblages than even-aged silviculture. Therefore, it is assumed that uneven-aged silviculture can be a useful tool for landscape planning to benefit biodiversity. Nevertheless, there is a lack of empirical studies regarding bird responses to uneven-aged silviculture in north European boreal ecosystems. Here we test the similarity of bird assemblage structure between mature forests within even-aged silviculture ('thinning') and uneven-aged silviculture ('selective felling'). In spring 2018 we censused breeding birds using territory mapping in 14 thinned stands and 14 selectively felled stands. We found higher abundance and different bird assemblages in thinned stands compared to selectively felled stands. The pied flycatcher, tree pipit and great tit contributed most to the variation of bird assemblages between the two management types. None of the species were more abundant in selectively felled than in thinned stands. According to functional guilds, the abundance of ground breeders, ground feeders and generalists was higher in thinned stands than in selectively felled stands, similar results were found in the species richness of long-distance migrants, ground nesters, secondary cavity nesters and generalists. Independent of management type, time since treatment had an overall effect on assemblage structures, the mistle thrush and wren were negatively correlated with time since treatment, while the chiffchaff showed the opposite trend. Our results suggest that at these locations and given this particular type of uneven-age management, selective felling is less suitable for some abundant generalists than even-aged forest stands reaching the thinning age. However, the results from this study does not provide clear management recommendations aiming to maintain biodiversity, as management guidelines should be based on red-listed species and not on common generalists. Nevertheless, our results stresses the urgent need for more long-term studies comparing the effect of these different silvicultural strategies on bird assemblages. [ABSTRACT FROM AUTHOR]

• Burning increased species richness of beetles compared to gap-cut and reference stands. • Species composition differed significantly between all three groups of stands. • Most species benefitting from burning are fire dependent/favored species. • Gap cutting maintained pre-treatment beetle assemblages but benefitted e.g., cambivores. • Both restoration methods are complementary to e.g., free development set-asides. Accelerating declines in biodiversity worldwide have accentuated the need for conservation actions. Unfortunately, the decline is unlikely to be reversed by traditional conservation alone, e.g., green tree retention at clear-felling and setting aside protected areas for free development. Instead the practice of ecological restoration has come to play an ever increasing role. Using a before-after control-impact experiment in boreal forest voluntary set-asides, we evaluated the usefulness of two methods of ecological restoration aimed at promoting biodiversity by emulating natural disturbances through restoration burning and artificial gap creation involving dead wood creation. In burned stands (n = 6) we removed up to 35% of the standing volume prior to burning, and in gap cut stands (n = 10) we removed the cut trees from every second gap; harvested trees covered costs for restoration. We used saproxylic and non-saproxylic beetles as a proxy for biodiversity to evaluate the two restoration methods. We compared species compositions of beetles collected with window traps one year before and one year after treatment. In addition, we compared catches in the treatments with those in untreated reference stands. Before treatment, we found no differences between the three groups of stands in terms of overall abundance, species richness or species composition. After treatment, the overall abundance of beetles was higher in the burned sites compared to the reference stands. Overall species richness was higher in burned stands compared to references and gap-cut stands. Gap-cut stands had higher species richness of cambivores and fire favoured species than reference stands. Species composition differed significantly between all three groups of stands. Among the 96 species that significantly contributed to the differences in species composition, 58 were more common in burned stands and 34 more common in gap-cut stands than in the other two stand groups. Nineteen of the 96 species are considered to be favored by forest fires, and 17 of these fire-favored species were more abundant in burned stands than gap-cut stands and/or references. Based on our results that burning and gap-cutting changed the beetle communities in partly different directions, we propose the use of both methods as complements to traditional conservation efforts in future attempts to improve conditions for biodiversity in managed boreal forest landscapes. [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]

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]

Abstract: The habitat requirements and effects of forest management on insects belonging to higher trophic levels are relatively unknown in forest ecosystems. We tested the effect of forest successional stage and dead wood characteristics on the saproxylic parasitoid (Hymenoptera, Ichneumonoidea) assemblage in boreal spruce-dominated forests in northern Sweden. Within each of nine areas, we selected three sites with different management histories: (1) a clear-cut (2) a mature managed forest and (3) an old-growth forest. Parasitoids were collected in 2003 using eclector traps mounted on fresh logs, which were either untreated (control), burned, inoculated with fungi, or naturally shaded, and on artificially-created snags. Both forest type and dead wood characteristics had a significant effect on parasitoid assemblages. Grouped idiobionts and some species, such as Bracon obscurator and Ontsira antica, preferred clear-cuts, while others, such as Cosmophorus regius (Hym., Braconidae) and other koinobionts, were associated with older successional forest stages. No single dead wood substrate was sufficient to support the entire community of parasitoids in any forest type, even when the regular host was present. In particular, snags hosted a different assemblage of species from other types of dead wood, with parasitoids of Tetropium spp. such as Rhimphoctona spp. (Hym., Ichneumonidae) and Helconidea dentator (Hym., Braconidae) being abundant. These results indicate that a diversity of dead wood habitats is necessary to support complete assemblages of beetle-associated parasitoids from early successional stages of dead wood and that parasitoids may be more sensitive to habitat change than their hosts. [Copyright &y& Elsevier]