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Forest management is an important component of global change as more than half of the world's forests are managed for human use. Although the effect of forest management on taxonomic diversity is well‐studied, we do not fully understand its impact on functional diversity. Understanding this is important to better predict how ecosystem processes will respond to global change scenarios and to implement efficient conservation actions. We conducted two large‐scale (~81 800 km2) research projects over 4 years in temperate forests of the northeastern USA to investigate how the functional structure of bird and mammal communities are affected by forest disturbance. We surveyed 85 bird species distributed in 115 sites using point counts, and 14 mammal species across 197 sites using camera traps. For each species, we selected functional traits that summarize key features of their biology, and for each site, we collected data on the level of forest disturbance based on forest loss events. We found that functional richness increased with forest disturbance for mammals but not for birds. Our results also showed that niche breadth (diet), morphological (body mass and wing length), and physiological (litter size) factors were the main determinants of the functional structure of both groups. These findings emphasize the complexity of making predictions about responses to forest management given the heavy dependence on the context and taxa studied. Overall we observed a limited response of functional diversity to forest management, which might indicate that the environmental changes generated by forest management in this region are less extreme than deforestation or conversion of natural forest to plantations of exotic species. Nonetheless, our results underscore the importance of investigating the effects of forestry on individual traits to develop strategies for managing for ecosystem functions. [ABSTRACT FROM AUTHOR]

Leaf-associated fungi, the fungi that depend on leaves to sporulate, have a rich Cenozoic record, however their earlier diversity is poorly characterized. Here we describe Harristroma eboracense gen. et sp. nov., a Middle Jurassic leaf-associated fungus colonizing the leaf cuticle of Nilssonia tenuicaulis (cycadophyte). To place our newly described species into a picture of the diversification of Mesozoic fungi, we reassess fossils with leaf-associated stromata in the context of fungal molecular phylogeny. Being melanized, with radiate stromata, and on leaves, H. eboracense and other fossils from the Jurassic and earlier periods are probably related to filamentous Ascomycota in the superclass Leotiomyceta. Characters needed for further resolution of leaf-associated fungal biology and classification, such as the presence of an ostiole for spore discharge and appressoria for entry into leaf tissue first appear in the Mesozoic fossil record. Among Early Cretaceous fossils, Spataporthe taylorii represents the oldest unambiguous evidence of perithecial Sordariomycetes while Protographum luttrellii and Bleximothyrium ostiolatum are the oldest Dothideomycetes thyriothecia. Environmental observations show that broad leaved gymnosperms (especially cycadophytes) growing in warm temperate wet forests might have been the first environment for the radiation of Leotiomyceta. [ABSTRACT FROM AUTHOR]

Plant species richness and composition are influenced by complex interactions between biotic and abiotic factors that operate on different spatial scales. Since spatial scales vary continuously in nature, it is expected that multiple factors simultaneously affect species richness and composition at an intermediate spatial scale (i.e., the mesoscale landscape level). Previous studies have shown that local topography and elevation are important factors for shaping intermediate spatial scale plant species richness; however, the relative importance of these factors has rarely been examined. Here, we used spatially explicit woody plant data to examine the factors that characterize the spatial pattern of primary evergreen forest biodiversity at the intermediate spatial scale. We found that the spatial pattern of species diversity in a predominantly warm temperate evergreen forest at the landscape level is mainly characterized by shifts in species composition along the elevation gradient. Our study also found that compositional shift along the elevational gradient was mainly caused by habitat specialization among congeneric species, suggesting that niche partitioning among closely-related species is a fundamentally important feature of the intermediate spatial scale species richness pattern. Furthermore, we found that specialization in a habitat of closely-related species can be established even within a limited environmental gradient. This suggests that biotic interactions among closely-related species may be an important factor driving habitat specialization, and biotic interactions may play an important role in shaping landscape-scale biodiversity patterns. [ABSTRACT FROM AUTHOR]

Prunus serotina is one of the most widespread alien tree species in temperate European forests. Although numerous studies revealed both negative and positive impacts on native ecosystems, only a few assessed the quantitative impacts along a species abundance gradient, based on aboveground biomass of per capita effects. Here we studied how alpha diversity of forest understory changes with increasing aboveground biomass of P. serotina. In Wielkopolska National Park (W Poland) we established 92 plots in both nutrient-rich and poor Pinus sylvestris stands. We assessed the effects of P. serotina proportion on understory species composition using non-metric multidimensional scaling (NMDS). We also assessed the effects of P. serotina proportion on alpha diversity metrics using generalized mixed-effects linear models, accounting also for stand age, soil C:N ratio, and light availability. P. serotina biomass ranged from 0.0 to 34.29 Mg ha−1 (with an average of 5.70 ± 0.83 Mg ha−1), comprising 0% to 17.26% (with an average of 2.93 ± 0.43%) of total woody species biomass. NMDS revealed a lack of P. serotina proportion effects on understory species composition. We found small positive impacts of P. serotina proportion on total species richness (+ 8.8 species along a gradient with a 10% increase of P. serotina biomass proportion) and functional richness (+ 0.08). The positive impacts of P. serotina were mostly related to the confounding effect of two factors: an increase in light availability facilitates both the development of understory plants as well as the growth of P. serotina. [ABSTRACT FROM AUTHOR]

Knowing what the highest-level mammalian carnivores and intermediate levels eat throughout the geography and how human activities may affect their community dynamics is relevant information to focusing and deciding on conservation efforts within a territory. In this review, we characterize geographically the accumulated knowledge about the trophic niche of terrestrial mammalian carnivore species and evaluate the spatial relationship between the species richness distribution and the geographical distribution of their trophic knowledge in Chile. We found 88 peer-reviewed papers that include trophic studies per se, theses, and short notes carried out in Chile, where at least one trophic element was reported for terrestrial mammalian carnivore species. We found a positive relationship between the species richness distribution pattern and the spatial distribution of accumulated trophic knowledge, i.e., most of the papers have been conducted in Central-southern Chile (Central Chile and Temperate Forest ecoregions) responding to the highest co-occurrence of carnivore species within the limits of the biodiversity hotspot, the most threatened area in the country. Despite this general relationship, we recognize gaps in knowledge regarding regions of the country that require more research effort, such as O'Higgins, Maule, and Ñuble regions, as well as focus efforts on certain species with no or almost no knowledge of their trophic ecology, such as Leopardus colocola, Lyncodon patagonicus and Conepatus chinga. Except for the northern Chilean ecosystems, there is a generalized report of high consumption of exotic mammals in the diet of carnivores in the center and south of the country. However, of the 98 localities recognized in the 88 papers, 20.4% correspond to an anthropized environment, while most (79.6%) correspond to a "non-anthropized" environment or protected area. We hope this review allows researchers and decision-makers to consider the knowledge and lack thereof of carnivore trophic interactions as an opportunity to conserve entire natural communities throughout the Chilean territory. [ABSTRACT FROM AUTHOR]

Closures in temperate forests have been widely used to evaluate the effects of livestock on conservation and restoration objectives, but their use with management objectives in integrated productive systems in native forests has been poorly studied. Given that the studies are concentrated in the northern hemisphere, it is essential to advance local research to provide management tools to ensure the continuity of the forest component and the functionality of the system. Therefore, we analyzed the response of vegetation to the temporary exclusion of livestock in silvopastoral systems in mixed Austrocedrus chilensis - Nothofagus dombeyi forests of northern Patagonia. We evaluated changes in the structure, composition and functionality of understory vegetation, as well as in the regeneration of dominant canopy species. We selected three medium-sized estates, and in each one established three plots and three paired closures, which were monitored for three years. Closures significantly affected the height growth of N. dombeyi saplings, and marginally the survival of A. chilensis seedlings, while the species richness, composition, cover and functional diversity of the understory showed no changes. The coverage of palatable species was not affected, possibly due to greater limitation by light than herbivory and the short time of exclusion. Under the conditions studied, short-term community closures do not appear to be a suitable tool in farm management to promote forage production or regeneration of the most sensitive forest species. [ABSTRACT FROM AUTHOR]

Aim: Quantifying the phylogenetic diversity of temperate trees is essential for understanding the processes that have shaped the modern distribution of temperate broadleaf forest and other major forest biomes. Here, we focus on Fagales, an iconic member of forests worldwide, to uncover global diversity and endemism patterns and investigate the distribution of root nodule symbiosis (RNS), an important morphological specialisation in this clade, as a key factor behind these patterns. Location: Global. Taxon: Fagales. Methods: We combined phylogenetic data covering 60.2% of living species, fine‐scale distribution models covering 90% of species, and nodulation data covering all species to investigate the distribution of species richness and phylogenetic diversity at fine spatial scales compared to the distribution of RNS. We identify abiotic environmental factors associated with RNS and with Fagales diversity in general. Results: We find the highest species richness in temperate east Asia, eastern North America, and equatorial montane regions of Asia and Central America. By contrast, relative phylogenetic diversity (RPD) is highest at higher latitudes, where RNS also predominates. We found a strong spatial structuring of regionalisations of Fagales floras, reflecting distinct Northern and Southern Hemisphere floras (except a unique Afro‐Boreal region), each with distinct RNS‐environment relationships. Main Conclusions: Although species richness and phylogenetic regionalisation for Fagales accord well with traditional biogeographic concepts for temperate forests, this is not the case for RPD. RNS is almost universal in the highest RPD regions, which may reflect ecological filtering promoting RNS in these regions. Our results highlight the utility of global‐scale, clade‐specific spatial phylogenetics and its utility for understanding drivers of diversity in species‐rich clades. [ABSTRACT FROM AUTHOR]

Simple Summary: The global biodiversity crisis poses many challenges for humanity, and continuing to classify and gain knowledge of the "hidden biodiversity" of less studied groups considered hyper-diverse insect groups, such as the parasitoid wasp (Ichneumonidae), is one of them. There is a particular need for more taxonomic and distributional knowledge of the Neotropics and its neighboring regions. We assessed the current knowledge of the Ichneumonidae, otherwise known as Darwin wasps, in Chile, a country with a diverse ecogeographic gradient, from the southern cold and humid tip of South America approaching the Antarctic Circle to the arid Atacama beyond the Tropic of Capricorn. Following the most up-to-date taxonomic knowledge, we assessed biogeographic relationships at the genus level and the spatial patterns of biodiversity at the species and genera levels along the latitudinal gradient. The results show that biogeographic relationships are based on six faunistic elements (cosmopolitan; endemic; Neotropical; Holarctic–Oriental; south-temperate; and Australasian), reinforcing the early view of two different areas for Chilean ichneumonids: a northern province and a Neantarctic realm, with a high percentage of endemic genera and species. Spatial biodiversity patterns assessed at different scales show a bimodal distribution of richness: around 34° and 38° S in the Metropolitan and Araucanía Regions. From an ecoregional perspective, richness is concentrated in the Valdivian temperate forests, but when assessed at a 0.5 × 0.5 cell scale, several outstanding cells are in the contact zone between the temperate forests and the Chilean Matorral in the Central Chilean biodiversity hotspot. Interpreting richness involves two phenomena difficult to disentangle: genuine species diversity and collection bias closer to areas with larger human populations. In contrast, the Atacama Desert shows little or no presence of Darwin wasps, which is to be expected due to the lack of potential hosts. These results reinforce the need to continue sampling and studying available collections to help close the knowledge gaps already recognized as Wallacean and Linnean shortfalls in order to gain additional information on potential threats to endemic genera and species. Ichneumonidae, or Chilean Darwin wasps, are an important component of South American hymenopteran diversity, but the taxonomic and distributional knowledge on this insect is still deficient. Taking advantage of recently updated taxonomic knowledge, we assessed biogeographic relationships at the genus level and biodiversity spatial patterns along the latitudinal gradient. The results show the presence of 264 species in Chile, arranged in 102 genera and 22 subfamilies. Biogeographic relationships are based on six elements (cosmopolitan (n = 50; 36%), endemic (n = 29; 21%), Neotropical (n = 22; 16%), Holarctic–Oriental (n = 19; 14%), south-temperate (n = 16; 11%) and Australasian) and composed of just three genera: Anacis, Labena, and Meringops. Species and genera show a bimodal distribution along the latitudinal gradient: around 34° and 38° S. From an ecoregional perspective, richness is concentrated in the Valdivian temperate forests, but when assessed at a 0.5 × 0.5 cell scale, several outstanding cells are in the contact zone between the temperate forests and the Chilean Matorral. On the other hand, the Atacama Desert shows little or no presence of Darwin wasps. The results agree with Charles Porter, who identified a northern province composed of Neotropical and cosmopolitan genera with their own representatives in the far north (11 genera), a distributional gap in the core of the Atacama Desert, and around 128 genera in Porter's Neantarctic realm, covering all of Chile from 25° S to Cape Horn, including the Juan Fernandez islands. These results reinforce knowledge gaps and the need for more sampling and studies of available collections. Due to sampling gaps at this stage, identifying a continued increase or decrease in richness towards higher latitudes is not possible. More taxonomic and distributional information is also needed to assess potential threats to endemic genera and species. [ABSTRACT FROM AUTHOR]

The future trajectory of global forests is closely intertwined with tree demography, and a major fundamental goal in ecology is to understand the key mechanisms governing spatio‐temporal patterns in tree population dynamics. While previous research has made substantial progress in identifying the mechanisms individually, their relative importance among forests remains unclear mainly due to practical limitations. One approach to overcome these limitations is to group mechanisms according to their shared effects on the variability of tree vital rates and quantify patterns therein. We developed a conceptual and statistical framework (variance partitioning of Bayesian multilevel models) that attributes the variability in tree growth, mortality, and recruitment to variation in species, space, and time, and their interactions – categories we refer to as organising principles (OPs). We applied the framework to data from 21 forest plots covering more than 2.9 million trees of approximately 6500 species. We found that differences among species, the species OP, proved a major source of variability in tree vital rates, explaining 28–33% of demographic variance alone, and 14–17% in interaction with space, totalling 40–43%. Our results support the hypothesis that the range of vital rates is similar across global forests. However, the average variability among species declined with species richness, indicating that diverse forests featured smaller interspecific differences in vital rates. Moreover, decomposing the variance in vital rates into the proposed OPs showed the importance of unexplained variability, which includes individual variation, in tree demography. A focus on how demographic variance is organized in forests can facilitate the construction of more targeted models with clearer expectations of which covariates might drive a vital rate. This study therefore highlights the most promising avenues for future research, both in terms of understanding the relative contributions of groups of mechanisms to forest demography and diversity, and for improving projections of forest ecosystems. [ABSTRACT FROM AUTHOR]

Functional diversity of bird assemblages has been disproportionally less recognized than taxonomic diversity. Especially, it has been less assessed in temperate primeval forests, serving as a reference point to the vast majority of forests more or less transformed by human activity. Therefore we aimed to determine the functional diversity of bird assemblages at the three levels of forest ecosystem organization: forest types, forest layers, and forest structures, and to determine mechanisms shaping the functional diversity of bird composition under primeval conditions of the Białowieża National Park (NE Poland). We used observations from a regular network of 96 points within six permanent plots in ash-alder and oak-lime-hornbeam forests, and we calculated functional diversity components and community-weighted mean values of birds' functional traits. Despite higher taxonomic diversity and functional richness in the ash-alder forest, we found higher values of other functional diversity indices the in oak-lime-hornbeam forest. We also found differences in taxonomic and functional diversity among forest layers. We attributed mechanisms shaping the bird assemblages in ash-alder forests with habitat filtering, while niche partitioning or limiting similarity in oak-lime-hornbeam habitat. Bird assemblages on the crown and emergent layers seem to be shaped by niche partitioning mechanisms, whereas bird composition at shrub and understory levels seems to be shaped by habitat filters. Our study revealed that structural diversity at all three levels is crucial for maintaining the functional diversity of bird assemblages in the primeval forest. [ABSTRACT FROM AUTHOR]

Summary: Biodiversity world‐wide has been under increasing anthropogenic pressure in the past century. The long‐term response of biotic communities has been tackled primarily by focusing on species richness, community composition and functionality. Equally important are shifts between entire communities and habitat types, which remain an unexplored level of biodiversity change.We have resurveyed > 2000 vegetation plots in temperate forests in central Europe to capture changes over an average of five decades. The plots were assigned to eight broad forest habitat types using an algorithmic classification system. We analysed transitions between the habitat types and interpreted the trend in terms of changes in environmental conditions.We identified a directional shift along the combined gradients of canopy openness and soil nutrients. Nutrient‐poor open‐canopy forest habitats have declined strongly in favour of fertile closed‐canopy habitats. However, the shift was not uniform across the whole gradients.We conclude that the shifts in habitat types represent a century‐long successional trend with significant consequences for forest biodiversity. Open forest habitats should be urgently targeted for plant diversity restoration through the implementation of active management. The approach presented here can be applied to other habitat types and at different spatio‐temporal scales. [ABSTRACT FROM AUTHOR]

Premise: The herbaceous layer accounts for the majority of plant biodiversity in eastern North American forests, encompassing substantial variation in life history strategy and function. One group of early‐season herbaceous understory species, colloquially referred to as spring ephemeral wildflowers, are ecologically and culturally important, but little is known about the prevalence and biogeographic patterns of the spring ephemeral strategy. Methods: We used observations collected by the Global Biodiversity Information Facility (GBIF) to quantify the ephemerality of 559 understory forb species across eastern North America and classify them according to a continuous ephemerality index (ranging from 0 = never ephemeral to 1 = always ephemeral). We then used this information to model where ephemeral forbs were most common across the landscape with the goal of identifying geographic and environmental drivers important to their distributions and ranges. Results: Only 3.4% of all understory wildflower species were spring ephemerals in all parts of their range, and 18.4% (103 species) were ephemeral in at least part of their range. Spring ephemerals peaked in absolute species richness and relative proportion at mid latitudes. Conclusions: Spring ephemeral phenology is an important shade‐avoidance strategy for a large segment of the total understory species in temperate deciduous forests. In North America, the strategy is relatively most important for forest understories at mid latitudes. The definitions of spring ephemerality we provide here serve as an important ecological context for conservation priorities and to evaluate responses of this biodiverse group to future environmental change. [ABSTRACT FROM AUTHOR]

Species distribution and resource utilization are a fundamental aspect of ecology. By analyzing the tree space usage by birds and determining the species composition of birds across different parts of trees, our study could shed light on the mechanisms shaping co‐occurrence patterns in bird communities. Therefore, our study aimed to determine the species composition of birds across different parts of trees. We investigated whether species richness differs between positions on a tree and how these positions influence the probability of occurrence of the 10 most frequently observed bird species. To achieve this, we observed birds within permanent plots in Białowieża National Park (BNP) and analyzed the distribution patterns of birds within six vertical and three horizontal sectors of trees. The compositional dissimilarity between tree sectors was assessed using detrended correspondence analysis. We employed generalized linear mixed‐effects models to examine differences in species richness. The majority of the BNP bird community was associated with the branches, while other birds occupied the tree crown trunks and the understory trunks. Species richness was the highest on branches in the crown part of trees, followed by lower species richness on trunks associated with crowns, and the lowest richness was observed on branches and trunks in the understory. These results indicate that branches in the middle and lower parts of the crown serve as avian diversity hotspots on trees, likely due to the abundance of various food sources. The differing patterns of tree usage by specific bird species may suggest the avoidance of interspecific competition for resources. The study results of tree usage by bird species obtained in the primeval forest provides a reference point for studies conducted in human‐altered woods. [ABSTRACT FROM AUTHOR]

Purpose: Simultaneous effects of more than one global change driver on ecosystem functioning have rarely been assessed. Methods: We disentangled the effects of region encompassing climatic and edaphic conditions, forest-management intensity and community plant diversity on litterfall quantity, quality and turnover in 27 temperate forests across an environmental gradient. Results: Region significantly influenced litterfall and organic layer mass and chemical quality and litter and element turnover. After accounting for the influence of region, increasing forest-management intensity (ForMI) significantly decreased litterfall mass, N, P and K concentrations and nutrient fluxes and slowed down litter and nutrient turnover. Because increasing ForMI reflected the man-made contributions of coniferous trees, these results can partly be attributed to the lower litterfall at our study sites and slower litter turnover of coniferous than deciduous trees. After accounting for the influences of region and ForMI, increasing diversity of the vascular plant community on the study plots measured as species richness or Shannon index significantly increased C and decreased N, P and S concentrations in litterfall. Together with the significantly decreased N and P concentrations in the organic layer with increasing plant diversity, these results indicated an increased within-stand nutrient-use efficiency and a more complete soil nutrient use with increasing plant diversity. Conclusions: Our results demonstrate that increasing ForMI, which is associated with increasing conifer shares, leaves element stocks in the organic layer unchanged but slows down C turnover and thus increases temporary C storage in soil organic layers. Moreover, community vascular plant diversity helps close nutrient cycles. [ABSTRACT FROM AUTHOR]

Evidence for widespread declines in arthropods is growing and climate change is one of the suspected drivers. Recent droughts in Europe were unprecedented in the previous centuries and we are only beginning to understand the impacts on ecosystems. We analysed a 24‐year dataset of carabid beetles from a temperate forest area in northeast Germany and investigated linear and non‐linear trends in carabid abundance, biomass, diversity and species traits. We were especially interested if and how these were linked to droughts at different temporal scales using the standardized precipitation evapotranspiration index (SPEI). We found significant linear declines in abundance and biomass with annual rates of −3.1% (0.95 CI [−5.3, −1]) and –4.9% (0.95 CI [−9.4, −1.6]), respectively. Non‐linear trends were closely related to the SPEI when considering the climatic water balance of the previous six years and showed severe declines between 2015 and 2022 (−71% abundance, 0.95 CI [−84, −61] / −89% biomass, 0.95 CI [−97, −59]). However, there remained a significant annual background‐decline of −2.1% (0.95 CI [−5.7, −0.2]) and −3.1% (0.95 CI [−6.5, −0.1]), respectively, which occurred independently of drought. We observed negative trends in standardized carabid diversity metrics and a shift in species assemblage that were less directly linked to droughts. Declining and drought‐sensitive species tended to be larger predators with low dispersal abilities. This study is among the very first to investigate the impacts of the current unprecedented drought on forest insects in central Europe. Our findings add to the concerning amount of evidence for widespread declines in arthropods while pointing towards weather anomalies and climate change as one important driver. [ABSTRACT FROM AUTHOR]

Regeneration status of tree species along elevation gradient in temperate hill forest was not understood greatly. Present research examined the tree diversity and its regeneration patterns along an elevation gradient in temperate hill forest, central Nepal. Data were collected from 300 sample plots within vertical elevation bands of 10, ranging from 1365 to 2450 m asl. A random sampling method was used for data collection in three seasons, winter, premonsoon and post monsoon seasons. Diameter at breast height (DBH) was used to broadly categorize the plant individual into trees, saplings and seedlings. The tree species richness ranged from 12 to 25 with density of 350 to 1200 individuals per hectare. Species richness of tree and sapling showed statistically significant unimodal pattern, which peaked at mid-elevation. Elevation showed a strong and positive linear correlation with the seedling density (Deviance = 0.99, p < 0.001) and a significant hump-shaped relationship with sapling density (Deviance = 0.95, p < 0.001). Similarly, elevations showed a statistically significant negative hump-shaped relationship with all trees, saplings and seedling stages (Deviances = 0.89, 0.87 and 0.57). The highest values of the Shannon-Wiener index and the lowest value of the Simpson index were found at mid-elevation for all growth forms. Nearly 92% of tree species were found at regenerating stage; 49% in a good renewal regeneration status, 32% in fair renewal regeneration, and 11% at a poor regenerating condition. Nevertheless, 4% of tree species were reported as non-regenerating stages and 4% were newly introduced species. Hence, the regeneration status of the study area was considered fairly well since sapling (78.5%) > seedling (10.6%) ≤ mature (10.9%). Among tested environmental variables, elevation and annual mean rainfall were the most influential factors in the regeneration of tree species. [ABSTRACT FROM AUTHOR]

Simple Summary: This study examined the question of how many different mammalian species reside in the Province of Chungnam, Korea, and the influence of environmental, climatic, and human factors. A special model that combines the distribution of each species was used. Distance to forest boundary, elevation, slope, human population density, and distance to water streams were the major factors in determining overall species richness, while climate factors showed relatively less importance. Of particular interest was the fact that the map of unique species aligned with the location of many mammal species. The model would be very helpful to land managers, as well as those who are seeking a method for accommodating greater species diversity. This study was conducted as an effort to examine the association between mammalian species richness and environmental, anthropogenic, and bioclimate factors in the Province of Chungnam, Korea, using a stacked species distribution model (SSDM) approach. An SSDM model was constructed using an extensive dataset collected from 1357 mammal sampling points and their corresponding forest, geographical, anthropogenic, and bioclimatic information. Distance to forest edge, elevation, slope, population density, and distance to water channels were identified as important variables for determining species richness, whereas the impact of bioclimate variables was less important. The endemism map showed a strong correlation with species richness, suggesting the important role of endemic species. Overestimation was observed in areas with lower species richness. However, the findings of the study still demonstrated that valuable insights can be obtained through the use of the SSDM, which may be helpful to land managers, aiding in the effective management of wildlife habitats, particularly in regions with an abundance of species richness and endemism. [ABSTRACT FROM AUTHOR]

The synthesis of a large body of evidence from field experiments suggests more diverse plant communities are more productive as well as more resistant to the effects of climatic extremes like drought. However, this view is strongly based on data from grasslands due to the limited empirical evidence from tree diversity experiments. Here we report on the relationship between tree diversity and productivity over 10 years in a field experiment established in 2005 that was then affected by the 2018 mega‐drought in central Europe. Across a number of years, tree species diversity and productivity were significantly positively related; however, the slope switched to negative in the year of the drought. Net diversity effects increased through time, with complementarity effects making greater contributions to the net diversity effect than selection effects. Complementarity effects were clearly positive in three‐ and five‐species mixtures before the drought (2012–2016) but were found to decrease in the year of the drought. Selection effects were clearly positive in 2016 and remained positive in the drought year 2018 in two‐, three‐, and five‐species mixtures. The survival of Norway spruce (Picea abies) plummeted in response to the drought, and a negative relationship between species diversity and spruce survival was found. Taken together, our findings suggest that tree diversity per se may not buffer communities against the impacts of extreme drought and that tree species composition and the drought tolerance of tree species (i.e., species identity) will be important determinants of community productivity as the prevalence of drought increases. [ABSTRACT FROM AUTHOR]

Broad-leaved deciduous forests in the transitional region from temperate to subtropical climate in China exhibit a diverse assemblage of species. The effects of potential biotic and abiotic factors on forest species diversity are currently of great interest. Here, we quantified the diversity of woody plant species across vertical strata in a fully recorded 25-ha permanent forest dynamics plot (500 × 500 m) in the Mts. Qinling of China using 4 indices: Pielou evenness index ( J SW ), Shannon entropy (H ), species richness (S ), and species abundance. Analysis of multivariate linear regression was employed to compare the influences of potential biological, topography, and soil variables on the alpha diversity for each of the 625 sub-plot (20 × 20 m) in the canopy layer, substory layer, and understory layer. The results displayed that the indices of the alpha diversity significantly varied among different forest vertical strata and they were mostly and significantly related to the DBH structure variable, soil available phosphorus (P), and altitude. Despite vertical strata of the studied forest, biological, topographic, and soil factors jointly showed reasonably strong explanatory power for species diversity. More than 12% of the variations of the alpha diversity in canopy layer and 16% in substory layer as well as 8% in understory layer could be collectively explained by biological, topographic, and soil factors. Our findings can contribute to the understanding of how environmental and biological factors interact to affect species diversity and thus are of great implication for the preservation of forest species diversity. [ABSTRACT FROM AUTHOR]

Forest canopies harbor extraordinary biodiversity, with Collembola being one of the most abundant arthropod taxa. However, much of the research on canopy biodiversity has focused on tropical and subtropical regions, leaving a gap in our understanding of canopy communities in temperate and boreal forests. Studying canopy Collembola along elevational gradients can be particularly informative because several environmental factors change with elevation, and these changes may mirror those seen along latitudinal gradients. To better understand and conserve canopy Collembola diversity along elevational gradients, natural forests are of particular interest. In this study, we used canopy fogging to sample canopy Collembola at four elevation sites (800–1700 m a.s.l.) on Changbai Mountain, northeastern China, representing three natural forest types. We examined changes in species richness, abundance and composition of canopy Collembola, and partitioned beta diversity into nestedness and turnover to identify processes driving changes in community composition. We identified 53 morphospecies among 10,191 individuals, with Entomobryidae and Hypogastruridae being the dominant families. The highest abundance and species richness were observed at 1400 m and remained at similar levels at 1700 m, indicating an increasing pattern with elevation. Species turnover was the main driver of changes in community composition with elevation. Our results provide insights into the shift of canopy Collembola communities across an elevational gradient in temperate boreal forests. [ABSTRACT FROM AUTHOR]

Aim: The phyllosphere microbiome is central to plant health, distribution, and ecosystem function, yet, we lack a clear understanding of the drivers shaping their diversity in mountain ranges. Here, we examined how the endo‐ and epiphytic phyllosphere microbiomes of mountains simultaneously respond to climate and leaf functional traits. Location: Temperate forests of Changbai Mountain Natural Reserve, China. Methods: We collected the leaves of dominant tree species along seven elevations from 800 to 1950. We investigated changes in species richness and Shannon diversity of endo‐ and epiphytic phyllosphere fungal and bacterial communities (using next‐generation sequencing of ITS2 and 16S) along an 1150 m elevational gradient. We also examined the direct and indirect effects of climate (mean annual temperature; MAT) and 13 leaf morphological and chemical traits on the microbiome of the phyllosphere. Results: Phyllosphere microbiome declined monotonically with increasing elevation, contrasting with the hump‐shaped biodiversity patterns that are commonly reported. We observed a steeper decline in epiphytic bacterial diversity than in endophytic bacteria, whereas conversely endophytic fungi diversity declined more dramatically with increasing elevation than epiphytic fungi. Host plant traits – those involved in resource uptake and leaf surface temperature – predominantly shaped the elevational patterns of endophytic phyllosphere microbiome, whereas MAT mostly increased the richness and Shannon diversity of epiphytic organisms. We also observed weak, but significant indirect effects suggesting that host plant traits are important biotic drivers mediating climate effects on endophytic phyllosphere microbiome. Also, no covariation between bacteria and fungi was observed (neither for endophytic nor for epiphytic organisms), supporting neutral associations between bacterial and fungal communities, irrespective of the elevation. Main Conclusions: Both direct and mediating effects of plant traits should be considered to better understand the drivers shaping the richness and Shannon diversity of endo‐ and epiphytic phyllosphere microbiomes, and more generally the plant–microbe associations. Our study also offers a trait‐based attempt to disentangle the effects of biotic and abiotic filters in shaping endo‐ and epiphytic phyllosphere microbiome along an elevational gradient. [ABSTRACT FROM AUTHOR]

Bark traits of trees often serve as a key factor determining the community structure of epiphytes. However, the extent to which barks modulate the relative importance of abiotic and biotic assembly processes of epiphytes is poorly understood. Here, using a community phylogenetic approach, we aimed to infer the assembly processes of epiphytic mosses and liverworts on tree species with varying bark traits in a temperate forest of central Japan. We observed a total of 56 moss and 35 liverwort species on 150 trees. Moss communities showed decreasing species richness and a tendency toward phylogenetic overdispersion, that is, higher phylogenetic diversity than expected by chance, in relation to increasing bark roughness and acidity. Along the same bark gradients, liverwort communities became phylogenetically clustered. Species richness of both mosses and liverworts increased with the nitrogen content of barks. The results indicate non-random assembly processes such as abiotic filtering associated with environmental harshness and microhabitat variety determined by barks. Our findings imply that bark traits modulate community assembly processes through which epiphyte diversity is maintained. [ABSTRACT FROM AUTHOR]

Simple Summary: This study represents the first investigation of the vertical distribution of Drosophilidae in the European part of Russia. Traps suspended at various heights in deciduous forests were used to collect the specimens. Among the collected species, Drosophila obscura Fll. and Scaptodrosophila rufifrons Lw. were the most abundant. The highest total number of drosophilid flies (10,429 individuals) was captured at a height of 1.5 m, while the lowest number (5086 individuals) was recorded at 12 m. Five distinct vertical distribution patterns of drosophilids were identified throughout the season, demonstrating significant differences between mycetobiont and xylosaprobiont ecological groups. The maximum species diversity occurred in June and September. Research of Diptera in temperate forests has demonstrated uneven vertical distributions of insects. In this study, we examined the vertical distribution, seasonal fluctuations, and species diversity of Drosophilidae species in the Mordovia State Reserve. This research marks the first exploration of drosophilid vertical stratification in the European part of Russia. Using traps, we collected flies in four deciduous forest sites between early June and mid-September in 2020. A total of 27,151 individuals from 10 genera and 34 drosophilid species were identified, with 6 species from 4 genera being new to the Republic of Mordovia. Drosophila obscura Fll. and Scaptodrosophila rufifrons Lw. were the most abundant species in traps. The total highest number of drosophilid flies (10,429 individuals) was captured at a height of 1.5 m, while the lowest number (5086 individuals) was recorded at 12 m. The average number of flies was 6240 and 5387 individuals at heights of 7.5 m and 3.5 m, respectively. However, the prevalence of drosophilid numbers at the 1.5-m height was not constant during the season. We found that in the second part of July the total fly counts at heights of 7.5 m and 12 m exceeded those at 1.5 m. We have described five different types of vertical distribution of drosophilids throughout the season, which differs markedly in mycetobionts and xylosaprobionts ecological groups. Species diversity demonstrated variations across different sites and tiers during the season, with peak diversity observed in June and September. [ABSTRACT FROM AUTHOR]

Aims: Microbial residue deposition is considered an important part of soil carbon sequestration. However, there is still a lack of understanding of the link between tree species composition and diversity and microbial carbon deposition, which hampers the rational selection and allocation of tree species for artificial carbon sequestration afforestation in northern China. Methods: In this study, plots from temperate planting forests (>60 years) were examined for the importance values of tree species, mycorrhizal types, tree diversity, and soil properties. Soil amino sugar was used as the biomarker to indicate the accumulation of fungi- and bacteria-derived carbon. Results: We found that tree species diversity and the importance values of tree species and mycorrhizal types were significantly positively correlated with soil microbial residual carbon. Hierarchical partitioning modeling showed that three groups of variables significantly affected soil microbial residual carbon, accounting for a total of 26.75% of the variation. Among them, tree species diversity accounted for the largest proportion (11.5%), and tree species diversity and importance values had a high joint impact (9.74%). The importance values of all AM-associated species constituted one of the most significant individual factors and could independently account for 10.9% of the variation in microbial residues. The findings of piecewise structural equation modeling showed that the importance of tree species had a large direct impact on GluN, GalN, and the GluN/MurN ratio. By influencing soil properties, the importance values of tree species also had indirect effects on soil microbial residual carbon. Conclusions: We suggest that an increase in the importance values of AM-associated tree species, such as Acer negundo L., will be accompanied by an increase in the total importance value of AM-associated tree species, which can significantly increase soil microbial residual carbon. [ABSTRACT FROM AUTHOR]

Reptiles are an important part of the vertebrate fauna in the temperate woodlands of south-eastern Australia. However, compared to birds and mammals, the long-term occurrence of reptiles across woodland growth types–old growth, regrowth, and replantings–remains poorly understood. Here, using 18-years of data gathered at 218 sites across 1.5 million hectares in New South Wales South West Slopes bioregion, we sought to quantify patterns of temporal change in reptile occurrence and determine if such changes varied between woodland growth types. Despite extensive sampling, almost 75% of our 6341 surveys produced no detections of reptiles. Significant survey effort exceeding 2000 surveys was needed over a prolonged period of time to record detections of 26 reptile species in our study area. Our analyses showed a temporal increase in estimated reptile species richness and abundance over 18 years. Such increases characterized all three vegetation structural types we surveyed. At the individual species level, we had sufficient data to construct models for five of the 26 species recorded. Three of these species were least commonly detected in replantings, whereas the remaining two were most often detected in replantings relative to old growth and regrowth woodland. We found evidence of a temporal increase in two skink species, a decline in one gecko species, and no change in the remaining two skink species. Although detections were consistently low, active searches were the best survey method, and we suggest using this method in habitats known to be hotspots for reptiles, such as rocky outcrops, if the aim is to maximize the number of individuals and species detected. Our findings highlight the value of all three broad vegetation structure types in contributing to woodland reptile biodiversity. [ABSTRACT FROM AUTHOR]

Changes in biodiversity often affect ecosystem functioning. However, most previous biodiversity and ecosystem functioning (BEF) studies have generally been limited to very small spatial grains. Thus, knowledge regarding the biodiversity–ecosystem functioning relationships across spatial scales is lacking. Moreover, the multiscale nature of biodiversity, and specifically β diversity (i.e., spatial heterogeneity in species composition) was still largely missing in BEF studies. Here, using the vegetation and functional trait data collected from four 6‐ha forest dynamics plots (FDPs) in temperate and tropical forests in China, we examine the scale‐dependent relationships between tree diversity and the aboveground biomass (AGB), as well as the roles of species spatial heterogeneity in determining the AGB. In tropical forests, the effect of species richness on AGB decreased with spatial grains, while functional dominance played a stronger role at larger spatial grains. In temperate forests, positive relationship between diversity and AGB occurred at all spatial grains, especially on smaller scales. In both temperate and tropical forests, β diversity was positively correlated with AGB, but weaker than α diversity in determining AGB. Overall, complementarity and selection hypothesis play dominant role in determining AGB in temperate and tropical forests, respectively. The roles of these underlying mechanisms are more pronounced with increasing spatial scales. β diversity, a hitherto underexplored facet of biodiversity, is likely to increase ecosystem functions by species spatial turnover and should not be neglected in BEF explorations. Our findings have practical implications for forest management and demonstrate that biotic heterogeneity plays an important positive role in ecosystem functioning. [ABSTRACT FROM AUTHOR]

Introduction. Bryophytes can reach levels of coverage sufficient to influence key ecological processes; for example, their water retention capacity can supply an appreciable amount of humidity to forest ecosystems. The variation in biomass and diversity of epiphytic liverwort species in a Mexican cloud forest (CF) in the state of Hidalgo was estimated along elevation and latitude gradients, as was the relationship between epiphytic liverwort structural attributes and environmental factors. Methods. Liverwort species were sampled in three municipalities with CF in Hidalgo State, at elevations of 1345-2019 m. In each municipality, two 0.1 ha plots were located at the two extremes of the gradient. For each of 10 trees per plot, three 10 × 10 cm areas of bark were selected as microplots, and from each microplot, samples of liverwort were obtained to determine structural data for the liverworts. Key results. Species diversity was highest at the upper elevation level (1985-2001 m), and lowest at the lower elevation level (1345-1375 m). The highest dry and saturated weight values (15.20 g and 83.30 g, respectively) were found at lower elevations, and the lowest (11.78 g and 60.04 g, respectively) at high elevations. Conclusion. Species diversity was positively related to elevation gradient, and species biomass decreased gradually with elevation. Beta diversity values were not associated with geographical distance between sites. Local factors, such as light input, available area, phorophyte species, humidity and temperature, may have more influence on the growth of epiphytic liverworts than elevation or geographical distance. [ABSTRACT FROM AUTHOR]

Wood-rotting basidiomycetes have been investigated in the Chinese forest ecosystem for the past 30 years. Two hundred and five pathogenic wood-decayers belonging to 9 orders, 30 families, and 74 genera have been found in Chinese native forests, plantations, and gardens. Seventy-two species (accounting for 35% of the total pathogenic species) are reported as pathogenic fungi in China for the first time. Among these pathogens, 184 species are polypores, nine are corticioid fungi, eight are agarics and five are hydnoid basidiomycetes. One hundred and seventy-seven species (accounting for 86%) cause white rot, while 28 species (accounting for 14%) result in brown rot; 157 species grow on angiosperm trees (accounting for 76.5%) and 44 species occur on gymnosperm trees (accounting for 21.5%), only four species inhabit both angiosperms and gymnosperms (accounting for 2%); 95 species are distributed in boreal to temperate forests and 110 in subtropical to tropical forests. In addition, 17 species, including Fomitopsis pinicola, Heterobasidion parviporum, and Phellinidium weirii etc. which were previously treated as pathogenic species in China, do not occur in China according to recent studies. In this paper, the host(s), type of forest, rot type, and distribution of each pathogenic species in China are given. [ABSTRACT FROM AUTHOR]

The temperate Kashmir Himalaya, regardless of its simple representation as a giant temperate forest, exhibits remarkable vegetation dissimilarity being inadequately perceived. We explored the species diversity and taxonomic composition of herbaceous stratum in 147 plots over 36.75 ha of temperate Kashmir Himalayan landscape, describing three heterogeneous forest types, viz., low-level blue pine (BP), mixed-conifer (MC), and subalpine (SA) forests. Regression and constrained ordination (canonical correspondence analysis) analyses are used to quantify the relevance of environmental variables in governing herbaceous species composition and diversity. Landscape-level richness of 245 species ranging from 113 species in BP forest to 173 species in SA forest is documented. Mixed conifer forest manifested maximal species richness and Whittaker-β score among the forest types. With an aggregate of 42 species, Asteraceae attributed the optimum species richness accompanied by Poaceae (19 spp.), Lamiaceae (16 spp.), and so on, besides 22 monotypic families. Fragaria nubicola proclaims the dominant species, while Trifolium pratens, Pimpinella diversifolia and Impatiens brachycentra represent the most significant indicator species in BP, MC and SA forests. The consequence of elevation gradient on species richness across the landscape proclaims a significant unimodal paradigm (p = 0.005) ascribed to environmental stress at both elevational extremes. Latitude and precipitation proved as influencing ecological gradients underpinning the distribution of species composition in BP forest. However, in MC and SA forests, geographic location and precipitation and elevation and precipitation are highly associated with CCA-1 axis. To optimize biodiversity protection, conservation efforts must take forest scale variations in flora into consideration. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms underlying the relationship between biodiversity and ecosystem function (BEF) is critical for the implementation of productive and resilient ecosystem management. However, the differences in BEF relationships along altitudinal gradients between forests and shrublands are poorly understood, impeding the ability to manage terrestrial ecosystems and promote their carbon sinks. Using data from 37962 trees of 115 temperate forest and 134 shrubland plots of Taihang Mountains Priority Reserve, we analyzed the effects of species diversity, structural diversity, climate factors and soil moisture on carbon storage along altitudinal gradients in temperate forests and shrublands. We found that: (1) Structural diversity, rather than species diversity, mainly promoted carbon storage in forests. While species diversity had greater positive effect on carbon storage in shrublands. (2) Mean annual temperature (MAT) had a direct negative effect on forest carbon storage, and indirectly affected forest carbon storage by inhibiting structural diversity. In contrast, MAT promoted shrubland carbon storage directly and indirectly through the positive mediating effect of species diversity. (3) Increasing altitudinal gradients enhanced the structural diversity-carbon relationship in forests, but weakened the species diversity-carbon relationship in shrublands. Niche and architectural complementarity and different life strategies of forests and shrubs mainly explain these findings. These differential characteristics are critical for our comprehensive understanding of the BEF relationship and could help guide the differentiated management of forests and shrublands in reaction to environmental changes. [ABSTRACT FROM AUTHOR]

Background: Hederahelix L. is an invasive weed species introduced in several regions of the world, so it is relevant to study its effects on the plant community and the changes occurring after its eradication. We established invaded (with/without removal of H. helix) and non-invaded (with/without removal of the understory) plots to compare some community attributes in an oak forest in Mexico City and monitored them every 2 months for 1 year, taking soil samples to compare some edaphic variables between the plots. If invasive species negatively affect natural regeneration, seedlings of native species would be less abundant in plots invaded by H. helix than in the non-invaded ones. As invasive species modify the soil microbiota through exudates and often allelochemicals, soil chemical variables would differ between invaded and non-invaded plots. Results: The abundance of native species was lower in the invaded plots, but the richness and diversity of species were not statistically different. The composition of the two invaded plots was similar to each other and more alike to that of the non-invaded plots. The species composition of the invaded plots was associated with soil potassium and phosphorus concentrations, whereas that of the non-invaded plots was more associated with soil nitrogen concentration. Conclusions: Following the removal of H.helix, several native species were registered, leading to a similar species composition as in the non-invaded plots, suggesting that some vegetation recovery can be expected following H. helix removal in 1 year. [ABSTRACT FROM AUTHOR]

Several species of the regional pool rarely become part of local communities. Such a considerable fraction of the species pool which remains absent but have potential to establish is referred to as dark diversity, and has till now remained understudied. In this study, we aimed to estimate the dark diversity, site-specific species pool, community completeness and species co-occurrence patterns in the Himalaya. Following a globally standardised sampling protocol, we delineated a circle of radius 10 km in the high-altitudes habitats of Kashmir Himalaya and selected two major habitat types: temperate coniferous forest and alpine grassland. Within each habitat type, we laid two 10-m2 core and two 50-m2 surrounding plots at natural and disturbed sites, and also thirty 10-m2 co-occurrence plots. The size of dark diversity was found higher at the disturbed sites (grassland: 23.43, forest: 29.07) in comparison to the natural ones (grassland: 21.52, forest: 26.08). Conversely, the site-specific species pool size was higher in the natural sites (grassland: 44.53, forest: 51.08) as compared to the disturbed ones (grassland: 35.43, forest: 45.07), and a similar trend was observed for the community completeness index at both the habitats. The majority of the species co-occurrences in both the habitats were truly random, therby indicating possibly least role of biotic and abiotic factors. Our study provides empirical estimates of dark diversity and quantifies how they differ in natural and disturbed sites in Kashmir Himalaya. These findings have immediate implications in guiding site-specific biodiversity conservation and ecosystem restoration in the study region, and also hold promise to be upscaled at much larger spatial scales. [ABSTRACT FROM AUTHOR]

Bryophytes play important role in forest ecosystem functioning and their distribution and diversity are driven by numerous environmental factors. The aim of the present study was to bring new insights in deeper understanding of terrestrial bryophytes diversity in temperate forests, as well as to determine the environmental factors which have predominant influence on ground-floor bryophytes. The survey was conducted in Fruška Gora Mountain (Serbia) across seven forest sites where ground-bryophytes were sampled. Soil moisture, temperature, and pH were measured as soil characteristics, while herbaceous cover, litter cover, stream distance, number of trees and shrubs were used as characteristics of stand structure. Species richness, Shannon diversity index, and evenness index were used as diversity measures. Generalised linear model and canonical correspondence analysis (CCA) were used to test the influence of environmental variables on bryophyte diversity. Litter cover was the most important explanatory variable, followed by soil moisture, stream distance and tree number, respectively. Overall, the stand structure was found to have a greater impact on ground-floor bryophyte diversity compared to soil characteristics. Identification of the most significant ecological factors affecting the diversity and distribution of bryophytes in forest ecosystems is of great importance in forest ecology with the aim of defining adequate management methods to preserve the biodiversity of forests, with particular emphasis on endangered and rare bryophyte species. [ABSTRACT FROM AUTHOR]

Species diversity has been shown to be influenced by environmental factors, but the mechanism underlying their relationship remains unclear across spatial scales. Based on field investigation data collected from 3077 sample plots in temperate forest ecosystems, we compared tree species richness, evenness and dominance at 10 km × 10 km, 30 km × 30 km and 90 km × 90 km spatial scales. Then, we detected the scale dependence of changes in tree species composition on climate, topography and forest structure using variation partitioning and quantified their contribution to tree diversity with gradient–boosted models (GBMs) and fitted their relationships. The magnitude of tree richness, evenness and dominance significantly increased with spatial scale. Ecological factors jointly accounted for 24.3%, 26.5% and 38.5% of the variation in tree species composition at the three spatial scales, respectively. The annual mean temperature had a strong impact on tree richness, evenness and dominance and peaked at an intermediate scale. Tree evenness and dominance increased with the variation of temperature but had upper and lower limits. Tree richness obviously increased with annual precipitation on multiple scales and decreased with annual sunshine duration at large spatial scales. Tree richness, evenness and dominance obviously increased with the variation in elevation and diameter at breast height at large scales and small scales, respectively. Tree dominance decreased with tree height at a small scale. The dependence of tree diversity on ecological factors increased with spatial scales. Furthermore, different factors exert various controls on tree diversity at different spatial scales, representing a comprehensive mechanism regulating tree diversity. [ABSTRACT FROM AUTHOR]

Community phylogenetic structure and diversity analysis are useful complements to species-centric approaches in biodiversity studies by providing new insights into the processes that drive community assembly. In this study, we aimed to understand the differences in the relative importance of abiotic filtering, biotic interactions, and dispersal limitation on community assembly of trees at different vegetation growth stages. We also examined the influence of geographical distance, elevation, terrain, and soil. Thus, we examined the phylogenetic structures and β-diversities of saplings and adults along different abiotic gradients. The results of the net relatedness index (NRI) showed that, instead of being random, the phylogenetic structure of saplings tended to be convergent, whereas that of adults tended to be divergent. This result implies that the relative forces of abiotic filtering and biotic interactions change throughout vegetation growth. The results of generalized dissimilarity modelling (GDM) showed that dispersal limitation (geographical distance) and abiotic filtering influenced the community assembly of both adults and saplings. This result confirmed our hypothesis that both deterministic and stochastic processes were prevalent. The explanatory rates of geographic distance and environmental factor distance to phylogenetic β-diversity were quite different between adults and saplings, which meant that the relative force of dispersal limitation and abiotic filtering had also changed. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of forest roadside on plant diversity and composition in the Hyrcanian temperate forest of northern Iran. To collect vegetation data, 116 rectangular sampling plots were established at two microhabitats (i.e., cut and fill slopes) of forest roads. For both microhabitats, the highest life form belonged to hemicryptophytes. Among the 85 identified species, 58 were native, 12 invasive, 9 potentially invasive, 5 pioneer, and 1 exotic. On the roadside microhabitats, the ground cover of the Rosaceae family, with 11 species, was the highest among plant families. The highest frequency of Grime's life history strategies was the competitive strategy. Shannon–Wiener diversity and species richness indices of cut slopes were significantly higher than those of fill slopes. Partial canonical correspondence analysis indicated that species composition on roadsides was primarily influenced by microhabitats, elevation, gradient, canopy cover, story layer, occurrence of bare soil, and clay content. Our study contributes to understanding how roadside microhabitats affect environmental conditions, which might be helpful to forest road managers when implementing best management practices. [ABSTRACT FROM AUTHOR]

Three hypotheses regarding relationships between community diversity and occurrences of rare and non-native species and community stability include: (1) diverse communities contain the greatest numbers of rare species, (2) hotspots of native species richness and abundance also support many non-native species, and (3) community diversity promotes stability. We explored these hypotheses by sampling plant communities during two years (2018, 2021) in 151, 0.05-ha plots across a landscape of temperate forests and open habitats (e.g., prairies) in Ohio, USA. Occurrence of rare plant species corresponded with the most species-rich and diverse (Shannon diversity index) communities in one or both study years. Species richness of native and non-native plants was positively associated both years but cover was not. Stability of species composition between 2018 and 2021 was unrelated to 2018 species richness and was negatively related to community diversity and evenness. The most diverse sites were not the most compositionally stable. Although statistically significant relationships occurred between community diversity measures and rare and non-native species distributions and community compositional stability, the relationships were often weak or mainly only evident at the extremes. Moreover, variance partitioning indicated that occurrences of rare and non-native species and community compositional stability were more closely associated with location effects within the landscape and community type than they were to community diversity. Nevertheless, when especially high or low, community diversity measures may facilitate predicting levels of other community components of conservation priority, such as rare species occurrences. [ABSTRACT FROM AUTHOR]

Modern tropical rainforests (TRFs) are one of the most ecologically important and species-rich biomes on the planet. However, the origin of modern TRFs is still debated, especially due to the incongruence between the fossil record and molecular data. Here, we test whether Campanian assemblages from northeastern Africa could represent fossil TRF vegetation. In so doing, we compare the investigated assemblages with other assemblages known to represent temperate forests, subtropical forests, and TRF in terms of leaf physiognomy, species richness, and taxonomic composition. We conclude based on fossil leaves that modern-looking TRFs already existed since 80 Ma during the Campanian in northeastern Africa in an area corresponding to 10 % of the modern Amazonian or 25 % of the Congolese TRF. The apparent conflict between the fossil record and phylogenetic evidence is due to the nearly complete absence of published tropical floras for the Cretaceous. [ABSTRACT FROM AUTHOR]

Headwater streams are highly heterogenous and characterized by a sequence of riffles and pools, which are identified as distinct habitats. That higher species richness and density in riffles than in pools is considered a general pattern for macroinvertebrates. As temperate winters can last long up to half a year, however, macroinvertebrate communities of riffles and pools may assemble differently under ices or snows. Particularly, defoliation concentrating in autumn can largely change habitats in both riffles and pools by litter patching. According to the absence or presence of litter patches, there exist four types of subhabitats, i.e., riffle stones, riffle litters, and pool sediments, pool litters, which are selectively colonized by macroinvertebrates. To study the spatial pattern and temporal dynamics of colonization, macroinvertebrates were surveyed in a warmer temperate forest headwater stream in Northeast China during four periods: autumn, pre-freezing, freezing, and thawing periods. Our study focused on functional trait composition, functional diversity and functional redundancy of macroinvertebrate communities. The colonization of macroinvertebrates was found to be significantly different in these subhabitats. Riffle stones supported higher taxonomic and functional diversities than pool sediments; litter patches supported higher total macroinvertebrate abundance and higher functional redundancy than riffle stones or pool sediments. The functional trait composition changed significantly with seasonal freeze-thaw in both riffle stones and pool sediments, but not in litter patches. Macroinvertebrate community in litter patches showed seasonal stability in taxonomic and functional diversities and functional redundancy. Thus, this study strongly highlights that litter patches play an important role structuring macroinvertebrate community over winter, supporting high abundance and maintaining functional stability. [ABSTRACT FROM AUTHOR]

Global climate change is expected to have pervasive effects on the diversity and distribution of species, particularly ectotherms whose body temperatures depend on environmental temperatures. However, these impacts remain difficult to predict, in part because ectotherms may adapt or acclimate to novel conditions or may use behavioural thermoregulation to reduce their exposure to stressful microclimates.Here we examine the potential for physiological and behavioural changes to mitigate effects of environmental warming on five species of ants in a temperate forest habitat subject to urban warming.We worked in eight urban and eight non‐urban forest sites in North Carolina, USA; sites experienced a 1.1°C range of mean summer air temperatures. At each site, we documented species‐specific microclimates (ant operative temperatures, Te) and ant activity on a transect of 14 bait stations at three times of day. In the laboratory, we measured upper thermal tolerance (CTmax) and thermal preference (Tpref) for each focal species. We then asked whether thermal traits shifted at hotter sites, and whether ants avoided non‐preferred microclimates in the field.CTmax and Tpref did not increase at warmer sites, indicating that these populations did not adapt or acclimate to urban warming. Consistent with behavioural thermoregulation, four of the five species were less likely to occupy baits where Te departed from Tpref. Apparent thermoregulation resulted from fixed diel activity patterns that helped ants avoid the most inappropriate temperatures but did not compensate for daily or spatial temperature variation: Hotter sites had hotter ants.This study uses a novel approach to detect behavioural thermoregulation and sublethal warming in foraging insects. The results suggest that adaptation and behaviour may not protect common temperate forest ants from a warming climate, and highlight the need to evaluate effects of chronic, sublethal warming on small ectotherms. [ABSTRACT FROM AUTHOR]

Our understanding of how bees (Apoidea) use temperate forests is largely limited to sampling the understory and forest floor. Studies over the last decade have demonstrated that bee communities are vertically stratified within forests, yet the ecology of bee assemblages immediately above the canopy, the canopy‐aerosphere interface, remains unexplored. We sampled and compared bee communities above the canopy of a temperate forest to the understory (1 m), midstory (10 m), and canopy (20 m) on the campus of the University of Massachusetts, in Amherst, Massachusetts, United States from April to August, 2021. Overall, we found that assemblages above the canopy had more bees than in the understory, were distinct in composition from all other strata, and included the greatest proportion of unique species. Bee abundance and species richness were highest in the understory throughout the spring (April and May) and decreased as the season progressed, while bee abundance and species richness at higher strata increased into the summer months. We also found that bees with preferences to nest in moist and rotting wood were largely restricted to canopy and midstory strata. We conclude that bee assemblages occupying the space above the forest canopy are abundant and diverse, and their unique composition suggests that this canopy‐aerosphere interface plays an additional role in the bee community of temperate forests. Alternatively, our findings question how forest bee communities should be defined while highlighting the need for research on fundamental processes governing species stratification in and above the canopy. [ABSTRACT FROM AUTHOR]

Tree species are known to predominantly interact either with arbuscular mycorrhizal (AM) or ectomycorrhizal (EM) fungi. However, there is a knowledge gap regarding whether these mycorrhizae differently influence biodiversity–ecosystem functioning (BEF) relationships and whether a combination of both can increase community productivity. In 2015, we established a tree‐diversity experiment by growing tree communities with varying species richness levels (one, two, or four species) and either with AM or EM tree species or a combination of both. We investigated basal area and annual basal area increment from 2015 to 2020 as proxies for community productivity. We found significant positive relationships between tree species richness and community productivity, which strengthened over time. Further, AM and EM tree species differently influenced productivity; however, there was no overyielding when AM and EM trees grew together. EM tree communities were characterized by low productivity in the beginning but an increase of increment over time and showed overall strong biodiversity effects. For AM tree communities the opposite was true. Although young trees did not benefit from the presence of the other mycorrhizal type, dissimilar mechanisms underlying BEF relationships in AM and EM trees indicate that maximizing tree and mycorrhizal diversity may increase ecosystem functioning in the long run. [ABSTRACT FROM AUTHOR]

Aim: Assessing the performances of different sampling approaches for documenting community diversity may help to identify optimal sampling efforts and strategies, and to enhance conservation and monitoring planning. Here, we used two data sets based on probabilistic and preferential sampling schemes of Italian forest vegetation to analyze the multifaceted performances of the two approaches across three major forest types at a large scale. Location: Italy. Methods: We pooled 804 probabilistic and 16,259 preferential forest plots as samples of vascular plant diversity across the country. We balanced the two data sets in terms of sizes, plot size, geographical position, and vegetation types. For each of the two data sets, 1000 subsets of 201 random plots were compared by calculating the shared and exclusive indicator species, their overlap in the multivariate space, and the areas encompassed by spatially‐constrained rarefaction curves. We then calculated an index of performance using the ratio between the additional and total information collected by each sampling approach. The performances were tested and evaluated across the three major forest types. Results: The probabilistic approach performed better in estimating species richness and diversity of species assemblages, but did not detect other components of the regional diversity, such as azonal forests. The preferential approach outperformed the probabilistic approach in detecting forest‐specialist species and plant diversity hotspots. Conclusions: Using a novel workflow based on vegetation‐plot exclusivities and commonalities, our study suggests probabilistic and preferential sampling approaches are to be used in combination for better conservation and monitor planning purposes to detect multiple aspects of plant community diversity. Our findings can assist the implementation of national conservation planning and large‐scale monitoring of biodiversity. [ABSTRACT FROM AUTHOR]

Land snails represent a large diversity of species in the forest floor. Some species prefer to stay in the leaf litter, while others like to climb up vegetation. They are considered generalist herbivores/decomposers. Although the exact trophic position of most species is often difficult to determine, a low rate of trophic niche partitioning within an assemblage is assumed. We compared isotopic niche sizes and overlaps between and within four local land snail assemblages using stable isotope Bayesian ellipses. We found significant differences in trophic niche size (expressed by corrected standard ellipse area) as a function of body size and lifestyle. We hypothesised that the larger niche size of smaller and/or arboreal snail species is due to their limited mobility and the presence of spatially structured food resources. In contrast, a broad and similar mixture of leaf litter sources results in a homogeneous diet for individuals of larger, highly mobile, epigean species, i.e., smaller niche size. We documented multiple overlaps of isotopic niches between species within an assemblage, although arboreal species exhibited slightly different niche positions, indicating specific diets. When comparing all pairwise combinations, we found that isotopic niches of species using different lifestyle did not overlap, in contrast to species using similar lifestyle. In addition, the trophic niches of opportunists with respect to lifestyle were intermediate between those of species from the outermost categories. Our results fit the general concept of variable and overlapping trophic niches in co-occurring snail species. However, we were able to demonstrate differences in species that rarely occupy the same microhabitat. [ABSTRACT FROM AUTHOR]

This research aimed to determine diversity of herbaceous layer and morphological traits of oriental beech trees (Fagus orientalis Lipsky) among three different development stages which comprised the initial, optimal, and decay in Hyrcanian forests of northern Iran. Herb-layer species diversity indices were recorded. A total of 98 beech trees were selected randomly in development stages of beech forest and total height, diameter at breast height (DBH), crown length, height/DBH ratio, crown ratio, crown surface area, stem and crown projection ratio were measured. Decay stage showed the highest richness and diversity indices, whereas optimal stage characterized by the highest evenness index. Regarding to plant functional traits, diversity and richness values of hemichryptophytes, geophytes and graminoids in decay stage were significantly greater than other stages. The ANOVA test showed the significant differences in morphological traits of beech trees among the three development stages, with the mean values of most variables being highest in the optimal and decay stages. In general, we conclude that there are significant differences among stages of forest development, depending on forest structure influence the characteristics of beech trees and herbaceous vegetation. [ABSTRACT FROM AUTHOR]

Conspecific negative density dependence (CNDD) is a potentially important mechanism in maintaining species diversity. While previous evidence showed habitat heterogeneity and species' dispersal modes affect the strength of CNDD at early life stages of trees (e.g., seedlings), it remains unclear how they affect the strength of CNDD at later life stages. We examined the degree of spatial aggregation between saplings and trees for species dispersed by wind and gravity in four topographic habitats within a 25-ha temperate forest dynamic plot in the Qinling Mountains of central China. We used the replicated spatial point pattern (RSPP) analysis and bivariate paircorrelation function (PCF) to detect the spatial distribution of saplings around trees at two scales, 15 and 50 m, respectively. Although the signal was not apparent across the whole study region (or 25-ha), it is distinct on isolated areas with specific characteristics, suggesting that these characteristics could be important factors in CNDD. Further, we found that the gravity-dispersed tree species experienced CNDD across habitats, while for wind-dispersed species CNDD was found in gully, terrace and low-ridge habitats. Our study suggests that neglecting the habitat heterogeneity and dispersal mode can distort the signal of CNDD and community assembly in temperate forests. [ABSTRACT FROM AUTHOR]

• Temporal spectral metrics show potential for mapping of tree species diversity. • Tree species diversity positively impacts multiple ecosystem services. • Different impacts of various forest attributes on ecosystem services. Tree species diversity is crucial for forest ecosystem services as it relates to ecosystem functions. However, it remains unclear how spatially continuous tree species diversity affects multiple ecosystem services in temperate forests that undergo various management practices. We mapped the spatial pattern of tree species diversity represented by the Shannon diversity index, H' in the temperate forests of Northeast China using 1,028 in situ observations and 846 Sentinel-2 images. We further analysed the relationships between tree species diversity and ecosystem services including carbon storage, water yield, and soil retention, while controlling for the covarying effects of multiple forest attributes including tree height, leaf area index (LAI), and stand age. Our results showed distinct spatial variations in tree species diversity across different forest management practices, with natural forests exhibiting a higher diversity compared to managed natural forests and planted forests. Tree species diversity was found to be positively associated with improved ecosystem services, particularly water yield and soil retention, while the effects plateaued above diversity of 1.0 (Shannon index values). We also showed that LAI was the most important factor influencing carbon storage, while tree species diversity and stand age were crucial for water yield and soil retention. These results highlight the importance of maintaining diverse tree species to improve ecosystem services in temperate forests, providing a robust framework for effectively monitoring and managing forest ecosystems with regards to sustainable forest functioning. [ABSTRACT FROM AUTHOR]

A growing body of evidence indicates that tree mycorrhizal association and species richness pronouncedly affect soil nitrogen (N) cycling. However, most studies have been conducted in temperate forests, and the roles of soil microbial communities have been largely overlooked. Here, based on 11 long-term dynamic monitoring sites in tropical forests, we investigated the effects of the dominance of trees associated with arbuscular mycorrhizal (AM) (by basal area) and tree species richness on soil N cycling, and explored the role of soil bacteria, archaea and fungi. Our results showed contrasting effects of AM tree dominance and tree species richness, with AM tree dominance-induced increases in soil ammonium N, nitrate N and the rate of net N nitrification, and tree species richness-caused decreases in ammonium N, nitrate N, the rate of net N mineralization and ammonification. Moreover, we found that the "plant-soil-microbe" interactions mainly triggered the changes in net N mineralization, ammonification and nitrification. It was mainly bacterial composition that directly affected soil N mineralization and ammonification, while fungal diversity only changed soil N ammonification. For soil N nitrification, the abundance of ammonia-oxidizing archaea (AOA) was the main drivers. These findings reveal the discrepancy in effects of the AM tree dominance and tree species richness on soil N cycling, highlighting microbe-mediated mechanisms in regulating soil N mineralization, ammonification and nitrification. • AM tree dominance and tree species richness oppositely affected soil N cycling. • AM tree dominance and tree species richness modulated soil microbiome. • Microbes were crucial in mediating tree effects on soil N cycling. [ABSTRACT FROM AUTHOR]

Pseudohydnum is characterized by gelatinous basidiomata with hydnoid hymenophores and longitudinally septate basidia. In this study, samples of the genus from North China were examined morphologically and phylogenetically using a dataset of the internal transcribed spacer of the ribosomal RNA gene and the nuclear large subunit rDNA. This study describes three new species, namely Pseudohydnum abietinum, Pseudohydnum candidissimum, and Pseudohydnum sinobisporum. Pseudohydnum abietinum is characterized by pileate and pale clay pink basidiomata when fresh, with a rudimentary stipe base, four-celled basidia, and broadly ellipsoid to ovoid or subglobose basidiospores (6−7.5 × 5−6.3 μm). P. candidissimum is characterized by very white basidiomata when fresh, frequently four-celled basidia, and broadly ellipsoid to subglobose basidiospores (7.2−8.5 × 6−7 μm). P. sinobisporum is characterized by ivory basidiomata when fresh, two-celled basidia, ovoid to broadly ellipsoid, or subglobose basidiospores (7.5−9.5 × 5.8−7.2 μm). The main characteristics, type localities, and hosts of Pseudohydnum species are listed.

Modern tropical rain forests (TRF) are one of the most ecologically important and species-rich biomes on the planet. However, the origin of modern TRF is still debated, especially due to the incongruence between the fossil record and molecular data. Here, we are testing whether Campanian assemblages from north-eastern Africa could represent fossil TRF vegetation. In so doing, we compare the investigated assemblages with other assemblages known to represent temperate forests, subtropical forests, and TRF in terms of leaf physiognomy, species richness, and taxonomic composition. We assume that modern-looking TRF already existed about 80 Ma ago during the Campanian in north-eastern Africa based on fossil leaves in an area corresponding to 10% of the modern Amazonian or 25% of the Congolese TRF. The apparent conflict between the fossil record and phylogenetic evidence is due to the more or less absence of published tropical floras for the Cretaceous. [ABSTRACT FROM AUTHOR]