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Highlights • The taxonomic and functional diversity of dung beetles depend on canopy management in cattle ranching systems. • Cattle ranching systems with trees, while preserving microclimatic and soil conditions, maximize diversity. • Dung beetle diversity was strongly reduced in open pastures. Abstract The disturbance of natural environments affects, among others, the diversity of dung beetle assemblages, which could have serious consequences for the ecological processes regulated by these insects. The objective of this study was to evaluate and compare species diversity and functional groups of dung beetle assemblages both in the native forest and in three livestock systems that differed in their structure and composition of vegetation: a livestock system with native trees, a livestock system with exotic trees (Pinus taeda), and traditional open pastures, in the semideciduous Atlantic forest of Argentina, in an area previously covered by continuous forest and currently with a heterogeneous landscape of native forest and different land uses. Pitfall traps baited with cow dung were used in the natural forests and the livestock systems studied. A total of 2461 beetles belonging to 38 species were captured. Treed livestock systems showed the highest species richness (0D) and diversity (1D and 2D). Twelve functional groups were identified. The native forest showed the highest functional group richness, while open pastures had the lowest. In general, livestock systems showed a low proportional abundance of telecoprid, diurnal and large beetles. Microclimate (average temperature and humidity) and soil conditions (soil composition: sandy or clayey) were closely associated with the species and functional group composition. Results confirm that cattle ranching with tree retention preserves dung beetle diversity, and suggest that cattle systems without canopy cover have higher impact (negative effects) than silvopastoral systems on both species and functional groups. [ABSTRACT FROM AUTHOR]

• Riparian forests are particularly vulnerable to non-native tree invasion. • Robinia pseudoacacia and Ailanthus altissima are by far the most frequent invaders. • Eucalyptus camaldulensis, Populus × canadensis and Ulmus pumila have spread recently. • Potentially invasible forests can provide information on the future threat posed by non-native trees. • Tailored strategies are needed for the management of non-native tree species. Many forest tree species have been moved outside their native range to provide goods and services elsewhere, but some of them have become invasive, causing negative impacts on biodiversity and human activities. The assessment and knowledge on the degree and scale to which forest ecosystems are invaded by non-native trees is of paramount importance for tailored policies and strategies aiming at forest conservation. By analyzing main databases and literature and applying a four-level scale of invasion (not currently invaded and with low invasibility; potentially invasible; moderately invaded; massively invaded), we assessed the current and potential occurrence of twenty-five invasive non-native trees across forest ecosystems in Italy. Vulnerability to invasion substantially differed across forest categories, with riparian forests being particularly vulnerable to invasion. Acacia dealbata , Juglans nigra , Populus × canadensis and Prunus laurocerasus invaded a relatively small number of forest categories but showed their potential to widen their impact on others. Furthermore, some non-native species showed a recent increase of their invasive status in Italy. This study identified the Italian forest categories and non-native tree species that deserve primary attention, and can support proper management and allocation of funding to protect forests from the spread of invasive tree species. [ABSTRACT FROM AUTHOR]

We assess how tree species richness and ecosystem services vary along a tropical urbanisation gradient in a rapidly expanding mega-city (Bangkok, Thailand). We conduct tree surveys in 150 1 km cells selected by random stratification across an impervious surface cover gradient. In each cell, surveys were conducted at the centre (representing typical conditions) and in the largest patch of trees (assessing woodland retention impacts). We estimated trees' contributions to i) carbon storage, ii) food production for people, iii) biodiversity support (production of food for frugivorous birds), and iv) economic value (assessed using regulations for using trees as collateral for financial loans). Surveys detected 162 species (99 natives) indicating substantial species loss relative to nearby natural forests. Despite this, and contrasting with typical patterns in temperate cities, tree species richness (including of natives) and ecosystem service provision is relatively stable across the urbanisation gradient. This finding has two important consequences. First, growing cities through high intensity developments that require less space may benefit regional biodiversity without compromising ecosystem services. Second, even the typically very small woodlands present in highly urbanised locations contribute to supporting biodiversity and providing ecosystem services; thus such woodlands require protection. Species richness is not strongly positively associated with most of our focal ecosystem services. Urban planners must therefore pay attention to both biodiversity and ecosystem services as these do not automatically accrue from each other, partly because non-native species contributed substantially to most ecosystem services except biodiversity support. Finally, trees provide substantial value as collateral for financial loans (averages of £643 ha at random locations and £2282 ha in wooded locations). Policies promoting such valuations may reduce tree removal and encourage tree planting, but the list of eligible species warrants revision to include additional species that enhance biodiversity support, ecosystem services, and resilience against future environmental instability. • Non-natives dominate and contribute substantially to ES but not biodiversity support. • Urbanisation has reduced tree species richness relative to natural forests. • Richness (total, natives, non-natives) and ES are stable along the urban gradient. • High density urban growth can benefit regional biodiversity without compromising ES. • Tropical and temperate systems respond differently to urbanisation. [ABSTRACT FROM AUTHOR]

Abstract: To recommend forestry practices favourable to birds, we estimated the relative importance of stand structure (mean tree height, overstory and understory cover), stand composition (from pure conifer or broadleaved to mixed conifer–broadleaf stands) and climate (altitude, aspect) on mountain forest birds (Mont-Ventoux, southern French Alps and Giffre valley, northern French Alps). Studies were conducted on species richness in forest birds (separated into species preferring broadleaves, preferring conifers or indifferent) and in cavity nesters. Climate, structure and composition had roughly equivalent weights on mountain forest birds, but their relative importance depended on the species group. Due to very contrasted climatic conditions, bird communities were the richest at low elevations in the northern site and at high elevations in the southern site. The richness of many ecological groups increased log-linearly with mean tree height; however, a decrease was observed for certain ecological groups at the northern site for a tree height above ca. 20–25m. Mixed conifer–broadleaf stands (Holm Oak, Downy Oak or Beech mixed with Scots or Laricio Pines on Mont-Ventoux; Beech or Beech with other broadleaves mixed with Spruce in the Giffre valley) did not have higher bird richness than pure stands. The negative impact of broadleaf presence on birds preferring conifers was not compensated for (Giffre valley), or barely so (Mont-Ventoux), by a corresponding positive impact on birds preferring broadleaves. Conifers do not appear to systematically support poorer bird communities than broadleaves; therefore, juxtaposing pure stands of different trees may be more sensible than insisting on mixed stands if such stands are hard to manage. Furthermore, the introduced Laricio Pine stands supported bird communities as rich as native Scots Pine stands on Mont-Ventoux. [Copyright &y& Elsevier]

This research presents the first description of the ectomycorrhizal (ECM) fungal community of the North American shagbark hickory (Carya ovata) tree growing outside its natural range. The diversity of ECM fungi associated with alien C. ovata stands was compared with the surrounding native oak–hornbeam forests. C. ovata, outside of its natural range, has a high ability to harbor and to retain compatible ECM fungal taxa. Eighty-nine ECM fungal taxa were identified in C. ovata stands along with 76 taxa in the surrounding multi-species native forests. Only 35% of taxa were shared between C. ovata and the surrounding forest, while 38% of taxa were identified only in C. ovata stands and 27% from the surrounding forest. We conclude that the remaining successfully acclimated plantations of exotic Carya trees in Poland may constitute a valuable pool of ECM fungi for native trees and thus contribute to the maintenance of fungal biodiversity. [ABSTRACT FROM AUTHOR]