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Copyright of Journal of Applied Ecology 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.)

Because of continuing degradation or deforestation in areas of undisturbed primary forest, there is a need to study the relative merit of strategies that mitigate their impacts on biodiversity and associated ecological functionality.Here, we provide a global synthesis of forest degradation or deforestation using 48 studies published in peer‐reviewed journals that use dung beetles as indicators given their sensitivity to anthropogenic disturbance and their relevance in performing essential ecological functions in terrestrial ecosystems.We evaluated forest cover associated with undisturbed primary forest degradation (i.e. degraded primary forest) and undisturbed primary forest deforestation (i.e. secondary forest, forestry plantations and forestry restoration implementation) on species richness, total abundance, biomass, functional groups' presence and ecological functions provided by dung beetles. Additionally, we determined whether if dung beetle responses to forest disturbances were geographically dependent.We found lower diversity and a decrease in ecological functions associated with all classes of disturbance in primary forest. However, the effects were less severe in the case of forest degradation compared to complete deforestation with natural regeneration of secondary forest, development of forest plantations or active forest restoration by planting indigenous trees. The Neotropical and Oriental regions are particularly vulnerable, given the elevated rates of undisturbed primary forest deforestation and its negative impact on their assemblages' diversity and ecological functions.Synthesis and applications. Our results show that efforts for the conservation of remaining undisturbed primary forests need to be prioritized, especially in tropical latitudes. However, in regions where primary forest conservation is not feasible, logging management programs in degraded primary forest may have a potential role in reducing negative impacts for dung beetle diversity and ecological functions. Moreover, we conclude that despite the negative effect of primary forest deforestation and implementation of secondary forest, forestry plantation and forestry restoration, they can be useful for partial recovery of diversity and ecological functions performed by dung beetles in areas lacking any primary forest (undisturbed or degraded) vegetation cover. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Applied Ecology 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.)

Schall et al. (2020) assessed how a combination of different forest management systems in managed forest landscapes dominated by European beech may affect the biodiversity (alpha, beta and gamma) of 14 taxonomic groups. Current forest policy and nature conservation often demand for combining uneven‐aged managed and unmanaged, set‐aside for nature conservation, beech forests in order to promote biodiversity. In contrast to this, Schall et al. (2020) found even‐aged shelterwood forests, represented by different developmental phases, to support highest regional (gamma) diversity.By pointing out that unmanaged forests included in our study are not old‐growth forests, Bruun and Heilmann‐Clausen (2021) challenge our conclusion as not providing sound scientific advice to societies. It is true that the studied unmanaged forests are not representing old‐growth forests as defined in the literature. However, we demonstrate the representativeness of our unmanaged forests for current beech forest landscapes of Central Europe, where managed forests were more or less recently set‐aside in order to develop old‐growth structures. We also show that the managed and recently unmanaged forests in our study already differ distinctively in their forest structures.We use this response to stress the role of forest reserves for promoting certain species groups, and to emphasise their importance as valuable research sites today and in the future.Synthesis and applications. We see two main conclusions from our study. First, unmanaged forests still matter. We agree with Bruun and Heilmann‐Clausen (2021) on the general importance of unmanaged, old‐growth or long‐untouched forests, and we do not question the importance of set‐aside forests for biodiversity conservation. However, a complete complementarity to managed systems may only reveal after many decades of natural development. Second, safeguarding biodiversity in largely managed forest landscapes should focus on providing a landscape matrix of different developmental phases with varying environmental conditions rather than on maximising the vertical structure within stands. Such landscapes can partly compensate for structures that are still missing in vital, dense and closed forests recently set‐aside or for unsuitable phases that may occur due to a cyclic synchronisation of forest structures in unmanaged forests. [ABSTRACT FROM AUTHOR]

Habitat connectivity is important for tropical biodiversity conservation. Expansion of commodity crops, such as oil palm, fragments natural habitat areas, and strategies are needed to improve habitat connectivity in agricultural landscapes. The Roundtable on Sustainable Palm Oil (RSPO) voluntary certification system requires that growers identify and conserve forest patches identified as High Conservation Value Areas (HCVAs) before oil palm plantations can be certified as sustainable. We assessed the potential benefits of these conservation set‐asides for forest connectivity.We mapped HCVAs and quantified their forest cover in 2015. To assess their contribution to forest connectivity, we modelled range expansion of forest‐dependent populations with five dispersal abilities spanning those representative of poor dispersers (e.g. flightless insects) to more mobile species (e.g. large birds or bats) across 70 plantation landscapes in Borneo.Because only 21% of HCVA area was forested in 2015, these conservation set‐asides currently provide few connectivity benefits. Compared to a scenario where HCVAs contain no forest (i.e. a no‐RSPO scenario), current HCVAs improved connectivity by ~3% across all dispersal abilities. However, if HCVAs were fully reforested, then overall landscape connectivity could improve by ~16%. Reforestation of HCVAs had the greatest benefit for poor to intermediate dispersers (0.5–3 km per generation), generating landscapes that were up to 2.7 times better connected than landscapes without HCVAs. By contrast, connectivity benefits of HCVAs were low for highly mobile populations under current and reforestation scenarios, because range expansion of these populations was generally successful regardless of the amount of forest cover.Synthesis and applications. The Roundtable on Sustainable Palm Oil (RSPO) requires that High Conservation Value Areas (HCVAs) be set aside to conserve biodiversity, but HCVAs currently provide few connectivity benefits because they contain relatively little forest. However, reforested HCVAs have the potential to improve landscape connectivity for some forest species (e.g. winged insects), and we recommend active management by plantation companies to improve forest quality of degraded HCVAs (e.g. by enrichment planting). Future revisions to the RSPO's Principles and Criteria should also ensure that large (i.e. with a core area >2 km2) HCVAs are reconnected to continuous tracts of forest to maximize their connectivity benefits. The Roundtable on Sustainable Palm Oil (RSPO) requires that High Conservation Value Areas (HCVAs) be set aside to conserve biodiversity, but HCVAs currently provide few connectivity benefits because they contain relatively little forest. However, reforested HCVAs have the potential to improve landscape connectivity for some forest species (e.g. winged insects), and we recommend active management by plantation companies to improve forest quality of degraded HCVAs (e.g. by enrichment planting). Future revisions to the RSPO's Principles and Criteria should also ensure that large (i.e. with a core area >2 km2) HCVAs are reconnected to continuous tracts of forest to maximize their connectivity benefits. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Applied Ecology 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.)

The expansion of oil palm plantations at the expense of tropical forests is causing declines in many species and altering ecosystem functions. Maintaining forest-dependent species and processes in these landscapes may therefore limit the negative impacts of this economically important industry. Protecting riparian vegetation may be one such opportunity; forest buffer strips are commonly protected for hydrological reasons, but can also conserve functionally important taxa and the processes they support., We surveyed leaf litter ant communities within oil palm-dominated landscapes in Sabah, Malaysia, using protein baits. As the scavenging activity of ants influences important ecological characteristics such as nutrient cycling and soil structure, we quantified species-specific rates of bait removal to examine how this process may change across land uses and establish which changes in community structure underlie observed shifts in activity., Riparian reserves had similar ant species richness, community composition and scavenging rates to nearby continuous logged forest. Reserve width and vegetation structure did not affect ant species richness significantly. However, the number of foraging individuals decreased with increasing reserve width, and scavenging rate increased with vegetation complexity., Oil palm ant communities were characterized by significantly lower species richness than logged forest and riparian reserves and also by altered community composition and reduced scavenging rates., Reduced scavenging activity in oil palm was not explained by a reduction in ant species richness, nor by replacement of forest ant species by those with lower per species scavenging rates. There was also no significant effect of land use on the scavenging activity of the forest species that persisted in oil palm. Rather, changes in scavenging activity were best explained by a reduction in the mean rate of bait removal per individual ant across all species in the community., Synthesis and applications. Our results suggest that riparian reserves are comparable to areas of logged forest in terms of ant community composition and ant-mediated scavenging. Hence, in addition to protecting large continuous areas of primary and logged forest, maintaining riparian reserves is a successful strategy for conserving leaf litter ants and their scavenging activities in tropical agricultural landscapes. [ABSTRACT FROM AUTHOR]

Industrial forestry typically leads to a simplified forest structure and altered species composition. Retention of trees at harvest was introduced about 25 years ago to mitigate negative impacts on biodiversity, mainly from clearcutting, and is now widely practiced in boreal and temperate regions. Despite numerous studies on response of flora and fauna to retention, no comprehensive review has summarized its effects on biodiversity in comparison to clearcuts as well as un-harvested forests., Using a systematic review protocol, we completed a meta-analysis of 78 studies including 944 comparisons of biodiversity between retention cuts and either clearcuts or un-harvested forests, with the main objective of assessing whether retention forestry helps, at least in the short term, to moderate the negative effects of clearcutting on flora and fauna., Retention cuts supported higher richness and a greater abundance of forest species than clearcuts as well as higher richness and abundance of open-habitat species than un-harvested forests. For all species taken together (i.e. forest species, open-habitat species, generalist species and unclassified species), richness was higher in retention cuts than in clearcuts., Retention cuts had negative impacts on some species compared to un-harvested forest, indicating that certain forest-interior species may not survive in retention cuts. Similarly, retention cuts were less suitable for some open-habitat species compared with clearcuts., Positive effects of retention cuts on richness of forest species increased with proportion of retained trees and time since harvest, but there were not enough data to analyse possible threshold effects, that is, levels at which effects on biodiversity diminish. Spatial arrangement of the trees (aggregated vs. dispersed) had no effect on either forest species or open-habitat species, although limited data may have hindered our capacity to identify responses. Results for different comparisons were largely consistent among taxonomic groups for forest and open-habitat species, respectively., Synthesis and applications. Our meta-analysis provides support for wider use of retention forestry since it moderates negative harvesting impacts on biodiversity. Hence, it is a promising approach for integrating biodiversity conservation and production forestry, although identifying optimal solutions between these two goals may need further attention. Nevertheless, retention forestry will not substitute for conservation actions targeting certain highly specialized species associated with forest-interior or open-habitat conditions. [ABSTRACT FROM AUTHOR]

1. The increased length of forest clear-cut edges is considered to be one of the main ecological consequences of silviculture. The effects vary over the landscape, and studies have shown that aspect is one important factor determining the extent of microclimatic edge effects across forest clear-cut boundaries. However, little is known about the relationship between contrasts in microclimate at edges and responses of ecological processes and biodiversity, such as growth, decomposition and species distributions.2. A field experiment was conducted in the boreal forest of northern Sweden to assess the effect of aspect at north- and south-facing edges using mosses as bioindicators. The growth of two species (Hylocomium splendensandHylocomiastrum umbratum) was evaluated during one growing season. Samples of each species were planted in pots at eight north- and eight south-facing forest clear-cut edges.3. Growth increased exponentially with distance from the edge to the interior, and there was a significant effect both in north- and south-facing edges. The percentage decline in growth at the edge was larger in the south- than in the north-facing edges.4. The spatial extent of the edge effect, when measured at the point of 90% of interior growth, was similar between north- and south-facing edges, although it differed between the two species evaluated.5. Synthesis and applications.The difference in exposure to sunlight between north- and south-facing edges was shown to modify the magnitude of the growth of a poikilohydric organism at the very edge, but not the depth of the edge influence. Aspect should be taken into account in management plans for conservation of boreal forests. In the northern hemisphere, wider buffers of uncut forest should be left at the south side than at the north side of retained forest patches. Those forest interior species that are most sensitive to alterations in microclimate will, however, need equal protection from edge effects at all aspects.Journal of Applied Ecology(2005)42, 518 –525doi: 10.1111/j.1365-2664.2005.01033.x [ABSTRACT FROM AUTHOR]