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Context: Urban forests provide ecosystem services such as temperature regulation, air purification, carbon sequestration and biodiversity conservation. It is important to perform baseline assessment and regular monitoring of biodiversity, vegetation dynamics and spatial structure of urban forests. Most cities suffer from the lack of a unified monitoring system. The heterogeneity of Moscow territory land use determines different functions and state of urban forests. To what extent are the forests of modern Moscow support natural resource and ecological potential, and what are the risks in maintaining the social and ecological needs of the population in the urban region? Objectives: Assessment of typological diversity, succession status and spatial structure of Moscow forests in the context of three sectors of different land use. Methods: This study integrates typological (cenotic), succession and fragmentation approaches on the basis of remote sensing data. Field relevés were used for cenotic classification into forest formations and association groups. Random forest algorithm was used for cartographic modeling. Forest patches assigned with formations and groups of associations were subject of diversity, dynamics and spatial structure of forests analysis. Results: Current study presents the assessment of the composition and spatial structure of the Moscow forests in the context of three sectors of different anthropogenic pressure and land use. 11 forest formations and 33 association groups were identified. Overall accuracy of cartographic modeling was 59% for association groups, and 67% for formations. Unsatisfactory ability of forests to support social and ecological needs of residents was revealed especially in the central part of the city. The combination of low fragmentation metrics with a high proportion of long-term derivative forest types is critical for the sustainable existence of forest cover within city center. With distance from the center a fairly high typological diversity of forests is noted. Conclusion: The combination of low fragmentation metrics with a high proportion of long-term derivative forest types is critical for the sustainable existence of the forest cover. Overall, the methodology and results of the work create a basis for regular monitoring of the Moscow forests, as well as in other urban areas. [ABSTRACT FROM AUTHOR]

Context: Forest loss and fragmentation are major drivers of biodiversity decline globally. However, with the widely recognised notion that biodiversity is multifaceted, few studies have assessed the responses of different diversity metrics to forest landscape changes. Objectives: Here, we used a multifaceted approach to assess the effects of landscape composition, forest fragmentation (patch-level) and local habitat heterogeneity on avian alpha-diversity (taxonomic, functional, phylogenetic and functional-phylogenetic diversity) of different ecological groups. Methods: We conducted fixed-radius point-count surveys across 32 Southern Mistbelt Forest fragments of southern KwaZulu-Natal and northern Eastern Cape, South Africa. Using linear mixed-effect models, we related multiple facets of bird diversity to landscape composition (i.e., matrix quality), habitat fragmentation (i.e., isolation distance and fragment-size) and local habitat heterogeneity (i.e., forest-structural complexity). Results: Matrix quality was a significant positive predictor of functional (FRic, sesFRic) and phylogenetic (sesPD) diversity of forest-dependent (forest specialist) species and functional diversity (FRic) of the whole community. Habitat fragmentation had significantly negative effects (i.e. increasing isolation distance and decreasing fragment size) on multiple diversity facets of all ecological groups, but non-forest-dependent (forest generalist) species showed no responses to isolation distance. Unexpectedly, diversity facets of forest-dependent species declined with increasing local vegetation complexity. Conclusions: Large and connected forest fragments are vital for maintaining avian diversity facets and promoting local vegetation complexity could contribute to the loss of forest-dependent species (forest specialists) in the naturally fragmented Southern Mistbelt Forests. [ABSTRACT FROM AUTHOR]

Context: Earth's forests are fragmented. Species' long-term persistence depends on their conservation in fragmented landscapes with remnants embedded in a matrix of human land use. This matrix influences species' persistence in fragments by determining their degree of isolation and the extent to which edge effects alter habitat. Matrix habitat is often dynamic, so its impact on persistence of remnant species changes over time. Objectives: Previous research showed that the abundance response of predatory beetle species to matrix habitat predicted their response in fragments with a log-response ratio of about 0.5. When abundance declined in the matrix, there was a smaller but predictable decline in fragments. However, the predictive utility of a fragment:matrix log-response ratio needs testing with functionally different species, more detailed data, and a focus on mechanism. Methods: In the Wog Wog habitat fragmentation experiment, we follow a detritivorous amphipod 27 years after forest fragmentation. Results: The amphipod's response in habitat fragments was predicted by its response in the matrix with a log-response ratio of about 0.5, similar to predatory beetles. The amphipod's response was explained by its abiotic niche. The amphipod's short-term response did not predict its long-term response. Conclusions: The log-response ratio might generalize across the invertebrate food web. For two groups within the Wog Wog experiment, a species' dynamic response in matrix habitat predicted its persistence in fragments. Future work should explore the generality of this finding. With knowledge of projected land use of matrix habitat, a species' matrix response could be used for management planning. [ABSTRACT FROM AUTHOR]

Context: Land use change is a major factor influencing biodiversity, but the mechanisms that drive species losses require further examination. Habitat loss often reduces biodiversity, but habitat fragmentation can increase biodiversity when examined independently. Processes driving this pattern remain largely unclear. Objectives: We aimed to determine the effects of habitat fragmentation on bumble bee populations after controlling for habitat amount, and to examine possible mechanisms behind observed effects. Methods: We sampled 22 species of bumble bees (Bombus sp.) across 50 unique sites located throughout the Canadian Rockies using a sampling design that minimized correlations between amount and spatial arrangement of land covers that may represent important habitat for bees. We modeled bumble bee abundance, species richness and diversity as a function of land cover metrics. Results: Effects of land cover fragmentation were dependent on both the measure of fragmentation used, and landscape scale. Bumble bee abundance was higher where nesting habitat (forest) and foraging habitat (grassland) were found adjacent to each other within 300 m, suggesting a landscape complementation effect where bees benefit from having access to both land cover types in proximity to one another. Having available habitat split into a greater number of patches was detrimental when considering the immediate area (0–300 m), but beneficial when quantified in more distant areas (300–600 m). Conclusions: Landscape complementation may be an important component behind positive fragmentation effects. Estimates of multiple measures of fragmentation are important when testing the impacts of land cover and landscape changes on species abundance and biodiversity. [ABSTRACT FROM AUTHOR]

Context: Urban remnant forest exists as patches scattered in an urban matrix. They are important sites for urban biodiversity conservation. Nevertheless, it is unclear how the properties of the urban matrix affect the biodiversity of remnant patches. Objective: Using data surveyed from 30 urban remnant forest patches in Guiyang, China, we intended to find out whether heterogeneity of the urban matrix affects the species richness of woody plants in these patches significantly. Methods: We used landscape indices calculated from land cover data to quantify compositional and configurational heterogeneity of the urban matrix. Then we analyzed the association between heterogeneity of the urban matrix and the species richness of woody plants in remnant forest patches using generalized linear regression models. Results: A significant positive association between compositional heterogeneity of the urban matrix and the species richness of tree sapling/seedlings existed when the urbanization level of the urban matrix was high. Also, compositional heterogeneity of the urban matrix correlated significantly with the species richness of shrubs in patches when the change rate of urbanization level of the urban matrix was low. Configurational heterogeneity of the urban matrix could enhance the association between patch attributes and the species richness of tree sapling/seedlings and shrubs. Conclusions: Heterogeneity of the urban matrix affected the woody plant diversity of the remnant forest patches through the interaction effects with patch attributes and the urbanization level of the urban matrix. We recommend including the management of heterogeneity of the urban matrix as an essential part of works to conserve biodiversity in urban remnant forest patches. [ABSTRACT FROM AUTHOR]

Context: The behavioural response of animals to edges between habitat patches and the matrix can influence population dynamics and species persistence in fragmented landscapes. Objectives: We aimed to answer two questions: (1) How do edge-effects between three land-cover types affect movement of adult male butterflies, and; (2) is response to edges influenced by perceptual range? Methods: In south-eastern Australia, we visually tracked the flight behaviour of the butterfly Heteronympha merope at edges between three land-cover types: native eucalypt woodland, farmland and exotic pine plantation. Using six replicates of each edge type, we released animals on both sides of the edges, and at two distances from the edge (5 m and 30 m). Results: Butterflies avoided pine edges, appeared to have low perceptual range in pines, and when released in pines, departed quickly. Butterflies often crossed from farmland into woodland and stayed, whereas none crossed from woodland into farmland or pines and stayed. Butterflies moved further away from pine edges when they were in woodland than when they were in farmland, suggesting edge-effects of one land-cover type depend on how animals respond to the alternative land-cover. Conclusions: Avoidance, and low perceptual range in plantations suggests plantations reduce landscape connectivity. Limited use of farmland is consistent with global reports that intensification of agriculture contributes to insect declines. Resource requirements of butterflies overlap with many other insects, and so extensive forestry plantations and intensive agriculture likely have negative impacts on a range of taxa, with improved land-sharing a possible solution. [ABSTRACT FROM AUTHOR]

Context: Forest loss and fragmentation are rapidly expanding across the tropics. Although forest loss is a major driver of the current biodiversity crisis, the effect of fragmentation remains debated, particularly for forest-specialist species. Objectives: We evaluated the univariate and combined effect of forest loss (percent of forest cover) and fragmentation (forest patch density) on populations of a forest-specialist primate, the black-fronted titi monkey (Callicebus nigrifrons), in the landscapes from a transitional zone between Atlantic Forest and Cerrado biomes. Methods: We surveyed titi monkey density in 14 landscapes. Using a multiscale and multimodel inference approach, we tested the relative effect of each landscape variable assessed at their respective scales of effect on titi monkey density. Results: Titi monkey density ranged from 0 to 12 groups/km2 and was best predicted by the combined effect of forest cover and patch density. Density increased in forest patches embedded in more deforested and fragmented landscapes. Interestingly, the effect of forest patch density was consistently positive along the entire evaluated forest cover gradient (9–42%). Conclusions: Our findings support that fragmentation per se can have positive effects on biodiversity, in this case, by increasing the likelihood that more individuals can be 'rescued' from deforestation and crowded in the remaining forest patches. Although the long-term consequences of living crowded in forest patches are unknown, a conservative approach for preserving this (and potentially other) forest-specialist species could be to promote forest restoration projects focused on increasing the number and/or size of forest patches in the landscape (i.e., reverse fragmentation). [ABSTRACT FROM AUTHOR]

Context: Historically, habitat edges were thought to increase diversity by combining communities from two habitats, but empirical results are mixed. Variation in edge responses may be driven by lumping specialists and generalists with divergent responses. Objectives: We examined arthropod communities associated with a habitat edge in an intertidal salt marsh in New Jersey. We predicted that herbivores, largely specialists, would decline along the habitat edge due to their failure to expand across the boundary, and specialist natural enemies should track prey. Generalists should be less impacted by the edge if they use resources from both sides. Thus, habitat edges should affect species composition more than species diversity. Methods: We studied the edge responses of 115 arthropod species to the habitat edge formed between Spartina patens (SP) and Spartina alterniflora (SA) throughout the growing season. Results: We found that the edge between SA and SP affected the abundance and composition of the associated arthropod community, but not species richness. Composition of herbivores, epigeic feeders, specialist natural enemies, and generalist predators shifted not only between SA and SP interiors, but also the edges. Compositional shifts were driven by dietary or habitat specialists. Conclusions: We found that edges change community composition via divergent responses by species with different resource requirements. This change in composition is not between two disparate habitat types but two congeneric grass species. Our results demonstrate that biodiversity losses due to edge effects associated with habitat fragmentation will not be random but will be driven by specialization and resource use. [ABSTRACT FROM AUTHOR]

Context: The habitat amount hypothesis (HAH) posits that local species richness is driven more by the amount of habitat in the surrounding landscape than by local patch size or habitat configuration. Habitat amount and configuration influence patch attributes, however, making it difficult to isolate these relative effects on local richness. Objectives: We tested the HAH in an experimental system in which the amount (10–80%) and configuration (clumped vs. fragmented) of habitat (red clover) were adjusted independently within individual 'landscapes' (256-m2 plots). Methods: We used generalized linear models and model-selection criteria to evaluate how arthropod richness at two local scales (1 m2 and 4 m2) varied as a function of the amount or fragmentation of habitat and of the size or shape of the local patch. Results: Local richness was largely independent of the amount or configuration of habitat, as well as patch size or shape. Local richness was best modeled as a constant for all surveys but the first, in which fragmentation alone best explained variation in species richness, followed by patch shape (which is an indirect effect of fragmentation). Habitat amount had an overwhelmingly positive effect on arthropod richness at the landscape scale, however. Conclusions: The HAH was not supported in this experimental system: local richness was generally unaffected by the amount of habitat in the surrounding landscape, whereas habitat configuration was sometimes important. Given that habitat amount affected landscape-wide richness, it may be that the HAH only applies at the 'landscape scale', at least in this system. [ABSTRACT FROM AUTHOR]

Context: Anthropogenic land use and cover changes impact biodiversity worldwide. However, ecological groups are differently affected by landscape composition and configuration. Understanding which groups are negatively affected and which thrive in human-modified landscapes is of paramount importance for conservation management, especially for species such as the frugivorous birds, which play an essential role in seed dispersal. Objectives: We evaluated the relative importance of landscape composition and configuration, explaining taxonomic and functional diversity and their effects on frugivorous birds in the Brazilian Atlantic Forest. Methods: We used a robust dataset encompassing 153 forest fragments in the Atlantic Forest hotspot. We classified species as frugivores based on the percentage of fruits in the diet, and used functional traits related to seed dispersal to measure functional diversity. Results: Our results showed that landscape composition was more important than landscape configuration explaining taxonomic and functional diversity of frugivorous birds. In addition, the interaction between landscape composition and configuration explained the loss of functional traits. Conclusions: We demonstrate a disproportional importance of landscape composition explaining taxonomic and functional diversity of frugivorous birds, whereas the traits related to seed dispersal were explained by both compositional and configurational variables. Thus, we highlighted the need to maintain high habitat amount to increase taxonomic and functional diversity of frugivorous birds. However, the interaction of landscape composition and configuration is of paramount importance to sustain functional traits of frugivores in tropical forest landscapes. [ABSTRACT FROM AUTHOR]

Objectives: Harmful effects of habitat loss and fragmentation can be detected across multiple spatial scales, yet most studies that aim to characterize these effects take place at a single spatial scale. Here we investigated responses in ant diversity to forest fragmentation across three spatial scales. Methods: We sampled ant diversity in a fragmented landscape in southeastern Brazil. We set transects with 15 pitfall traps (local scale response) within 16 forest fragments (fragment scale response) distributed in eight paired fragments separated by roads (mesoscale response). We measured habitat features at local, fragment and mesoscales and across the landscape. For each spatial scale, we then assessed the effects of ecological drivers measured at the same and subsequent higher spatial scales. Results: Local diversity was higher with closer proximity to the matrix, and in fragments with high vegetation density. Both fragment species richness and β-diversity were higher in less circular fragments. However, at the mesoscale (pairs of fragments), total species richness decreased with increasing pasture matrix in the landscape (landscape driver). Conclusions: Edge and matrix effects lead to increased ant species richness at small spatial scales (due to an increase in generalist ants). However, when analyzed at a higher spatial scale, the responses to these effects were in fact reversed, leading to a decrease in ant diversity. Thus, we suggest that conservation efforts should take a multi-scale perspective (from local to landscape) and aim to protect both local and fragment characteristics that can buffer edge effects, as well as improve matrix quality in the landscape. [ABSTRACT FROM AUTHOR]

Context: Habitat loss is widely recognized as the main driver of biodiversity loss around the globe, yet the effects of habitat fragmentation on biodiversity have been extensively debated in recent years. Objectives: We used a robust dataset of medium and large-sized mammals to test (a) the Habitat Amount Hypothesis, which postulates that species richness can be mainly predicted by the total amount of habitat surrounding the sampling site, and (b) the effects of habitat fragmentation per se, which may be expected to be weak or mainly positive on species richness. Methods: We compiled information on the occurrence of mammal species in 166 forest fragments across the Atlantic Forest. For each forest fragment, we extracted information on patch size, percentage of forest cover (a proxy for habitat amount), and edge density and number of fragments (fragmentation metrics). We related these metrics to mammalian richness considering separately for all species, forest-dependent species, disturbance-tolerant species, and different trophic guilds. Results: All richness measures strongly declined with decreasing forest cover, yet were unaffected by patch size, number of patches and edge density. The only exception occurred with herbivore richness, which was affected by number of patches. However, we found fragmentation per se effects only for herbivore richness. Conclusions: Our results show that mammal richness increased with habitat amount at the landscape, whereas habitat fragmentation per se had significant negative impacts on herbivores only. We therefore recommend maintaining highly forested landscapes and restoring severely deforested areas, being essential for ensuring high richness of mammals. [ABSTRACT FROM AUTHOR]

Context: Biodiversity is highly affected by industrial forestry, which leads to the loss and fragmentation of natural habitats. To date, most conservation studies have evaluated associations among a single species group, forest type, or spatial scale. Objective: The objective was to evaluate the richness of multiple species groups across various forest types and characteristics at multiple scales. Methods: We used the occurrence data for 277 species of conservation interest from 455 stands of high conservation value, including four species groups and four forest types. Results: Local, landscape, and regional forest characteristics influenced biodiversity in a non-uniform pattern among species groups and forest types. For example, an increased local spruce basal area in spruce forests was associated with higher vascular plant and bryophyte richness values, whereas macrofungi and lichen richness were positively correlated with deadwood availability, but negatively correlated with the spruce volume in the landscape. Furthermore, landscapes with twice as much mature forest as the average, had more than 50% higher richness values for vascular plants, macrofungi, and lichens. Conclusion: Among sessile species groups in northern forests, a uniform conservation strategy across forest types and scales is suboptimal. A multi-faceted strategy that acknowledges differences among species groups and forest types with tailored measures to promote richness is likely to be more successful. Nevertheless, the single most common measure associated with high richness across the species groups and forest types was mature forest in the landscape, which suggests that increasing old forests in the landscape is a beneficial conservation strategy. [ABSTRACT FROM AUTHOR]

Context: Determining the appropriate scale at which to study species' interactions with their environment is a great challenge. Objective: We investigated the spatial extent at which landscape structure affects the occurrence of four species of terrestrial mammalian herbivores in the Brazilian savannas and examined whether those scales could be explained by species ecological traits and how forest habitat was operationally defined. Methods: Using maps of forest cover, camera trapping and occupancy modelling, we determined the relations between three landscape metrics (percentage of forest cover, patch density and edge density) and the occurrence of four species. To determine the optimal scale of effect for each species, we computed landscape metrics at different spatial extents (from 0.5 to 10 km radius) from camera trap locations and for three forest maps, each using different operational definitions of a forest pixel: minimum of tree cover of 25, 50 or 75%. Results: The occupancy models revealed scales of effect of 0.5 to 2 km with the scale of effect being similar among three of the species. However, the probability of a scale of effect being detected depended upon how forest is operationally defined, being greater when forest was defined with greater tree cover, particularly for forest-specialist species. Conclusions: Besides biological traits, the way habitat is operationally defined shapes our ability to detect the scale of effects. Thus, it is necessary not to adopt a multi-scale approach, but also to use multiple operational definitions of habitat, considering particularities of how each species interact with their environment. [ABSTRACT FROM AUTHOR]

Context: The patterns and causes of forest transition have been extensively studied, identifying socio-economic drivers of land use deintensification and the associated forest expansion. However, most studies do not take into account the origin of the dominant species of new forests (i.e. native or exotic), which affects biodiversity and the provision of ecosystem services. Objectives: We develop a framework integrating forest transition, forest succession and biological invasion theories to identify the socio-environmental conditions that facilitate different pathways of spontaneous forest transitions in a subtropical mountain basin. Methods: We used Landsat images and Random forest classifier to detect land cover changes over 30 years (1988–2017). We used generalized additive models to identify socioeconomic and biophysical variables associated with expansion of native and exotic-dominated forests. Results: Expanding native forests are scattered throughout the whole basin under a broad spectrum of socioeconomic and environmental conditions. In contrast, the new forests dominated by exotic species were aggregated around their focal introduction areas and their expansion was associated with accessibility and specific land uses (livestock or residential use). Conclusions: Understanding the pathways of alternative forest transition involves the integration of land science, forest succession theory and invasion ecology. Land science explains the availability of sites to be reforested. The species composition of new forests depends on the availability of propagules, dispersal agents and competitive relationships between species (forest succession theory). Invasion ecology explains the role of introduction areas (which are often associated with residential use) of exotic species in the successional process. [ABSTRACT FROM AUTHOR]

Context: Tropical forests are great reservoirs of carbon but they still suffer high rates of deforestation despite their importance. Yet, large uncertainty remains about the effects of landscape-level forest loss on biomass of forest remnants, and how these effects vary with disturbance intensity at larger regional scales. Objectives: We evaluated whether the effects of forest loss on aboveground biomass (AGB) and stem density depend on the regional disturbance context. We predicted stronger responses to forest loss in intermediately disturbed regions (e.g. moderately deforested and defaunated). Methods: Using a large dataset (10.399 trees) from Brazil and Mexico, we tested the response of AGB and stem density to landscape-level forest loss. We used 136 old-growth forest sites encompassing a gradient of forest cover distributed in eight Neotropical regions with contrasting disturbance conditions. Regional disturbance was ranked according to a gradient of deforestation level and history, matrix harshness, and defaunation degree. Results: We found that forest loss simplified forest structure within forest remnants by decreasing AGB, but mainly in moderately disturbed regions. Yet, stem density was weakly related to forest cover in most regions. Conclusions: The regional context can mediate the effect of landscape structure on AGB. Preventing forest loss and increasing forest cover at landscape scales are needed to preserve AGB and carbon stocks in anthropogenic landscapes. Such management strategies can be more effective in moderately disturbed regions where relatively small increases in forest cover can significantly enhance AGB, thereby optimizing the delivery of carbon storage and other key ecosystem services. [ABSTRACT FROM AUTHOR]

Context: Island Biogeography Theory and Habitat Amount Hypothesis postulate species richness and densities to increase with connectivity and habitat amount, while niche theory highlights the importance of environmental heterogeneity for species coexistence. Additional ecological niches in heterogeneous landscapes increase species richness and functional and phylogenetic diversity, but larger, less isolated habitats are expected to enlarge species densities by mass effects without effects on functional or phylogenetic diversity. Objectives: We assessed the relative contribution of habitat amount, isolation and environmental heterogeneity on taxonomic, functional and phylogenetic diversity of the particular canga vegetation, i.e., rupestrian savannas associated to banded ironstone outcrops from the Carajás Massif, Eastern Amazon. Methods: We sampled vegetation at 48 sampling points comprising different physiognomies from 5 canga patches. Diversity measures were modelled as response variables in linear mixed models, using non-collinear predictors of habitat amount, isolation and environmental heterogeneity. Results: Diversity and species composition differed among canga physiognomies, indicating that environmental filters segregate canga plant metacommunity in physiognomy-specific species pools. Landscape roughness, a proxy for heterogeneity on the landscape level, increases species densities and functional richness. Additionally, habitat amount was positively associated with the degree of phylogenetic relatedness and functional diversity in communities. Conclusions: Our results suggest that configurational landscape heterogeneity increases the number of available ecological niches, while larger habitat amounts select for functionally and phylogenetically convergent species. These different underlying mechanisms need to be considered for management plans and reserve design for canga ecosystems, so that functional canga portions can be protected. [ABSTRACT FROM AUTHOR]

Context: Dead wood is a key habitat for saproxylic species, which are often used as indicators of habitat quality in forests. Understanding how the amount and spatial distribution of dead wood in the landscape affects saproxylic communities is therefore important for maintaining high forest biodiversity. Objectives: We investigated effects of the amount and isolation of dead wood on the alpha and beta diversity of four saproxylic species groups, with a focus on how the spatial scale influences results. Methods: We inventoried saproxylic beetles, wood-inhabiting fungi, and epixylic bryophytes and lichens on 62 plots in the Sihlwald forest reserve in Switzerland. We used GLMs to relate plot-level species richness to dead wood amount and isolation on spatial scales of 20–200 m radius. Further, we used GDMs to determine how dead wood amount and isolation affected beta diversity. Results: A larger amount of dead wood increased beetle richness on all spatial scales, while isolation had no effect. For fungi, bryophytes and lichens this was only true on small spatial scales. On larger scales of our study, dead wood amount had no effect, while greater isolation decreased species richness. Further, we found no strong consistent patterns explaining beta diversity. Conclusions: Our multi-taxon study shows that habitat amount and isolation can strongly differ in the spatial scale on which they influence local species richness. To generally support the species richness of different saproxylic groups, dead wood must primarily be available in large amounts but should also be evenly distributed because negative effects of isolation already showed at scales under 100 m. [ABSTRACT FROM AUTHOR]

Context: The importance of societal factors in shaping forest area, structure and composition through economic activity, policy, governance, and population changes is frequently acknowledged in ecologic studies, however the specific socioeconomic factors that lead to land use change through time are rarely articulated. Objectives: We present a consilience-driven approach for integrating socioeconomic and paleoecologic data to explore land use legacies and interpret causes of past abrupt environmental change. Methods: We combine paleoecologic history reconstructed from pollen analysis of lake sediments and contemporary historical narratives of socioeconomic change developed from archival sources illustrated by three case studies from two sites in the Italian Apennines. Results: We found that in the Rieti Basin, central Italy, between 850 and 900 AD (coeval with the beginning of the Medieval Climate Anomaly—MCA), under the new Carolingian rule, the imperially sponsored monastery at Farfa consolidated small landholdings, leading to more active land management and significant forest loss for agricultural activities. In contrast, at Pollino in southern Italy between 1050 and 1100 AD, also during the MCA, Norman conquest helped to convert a deforested landscape into an actively managed fir forest for timber needed for construction. At both sites, depopulation and land management between 1350 and 1400 AD caused by the Black Death, led to forest rewilding, however each site took a different trajectory. Conclusions: The studies presented offer examples of how the integration of detailed historical narratives with high-resolution paleoecologic reconstructions can provide a more nuanced examination of the interrelationship between societal factors and climate forcing in shaping land-use legacies and has the capacity to illuminate the link between specific human pressures and pathways of ecological change over many centuries. [ABSTRACT FROM AUTHOR]

Context: Since the nineteenth century, rural areas have experienced progressive abandonment mostly due to socioeconomic changes, with direct and indirect effects on forest disturbance regimes occurring in these human-dominated landscapes. The role of land abandonment in modifying disturbance regimes has been highlighted for some types of disturbances, albeit being still somewhat overlooked compared to climate change. Objectives: This literature review is aimed at highlighting the most relevant effects of land abandonment and land-use legacy on the regime of different types of forest disturbances, providing insight into land-use change/disturbances interactions. Methods: We searched in the Scopus and Web of Science databases for relevant studies at the global scale dealing with eight major natural disturbances: avalanche, flooding, herbivory, insect outbreak, landslide, rockfall, wildfire and windthrow. We classified papers into five relevance classes, with the highest score (4) assigned to studies quantitatively measuring the interactions between abandonment dynamics and disturbance regimes. Results: Most papers focused on wildfires in Mediterranean Europe in the twentieth century, where landscape homogenisation and fuel build-up contributed to worsening their frequency, size and severity. Dense forests developed following land abandonment instead exert inhibiting effects toward mass movements such as avalanches, rockfalls and landslides. Regarding the other investigated disturbances, we found only a few studies presenting site-specific and partly contrasting effects. Conclusions: Land abandonment triggers ecological processes at the landscape scale, altering land cover patterns and vegetation communities, which in turn affect disturbance regimes. Implications for land and resource management mostly depend on the stage at which post-abandonment secondary succession has developed. [ABSTRACT FROM AUTHOR]

Context: Understanding how landscape fragmentation affects functional diversity, defined as the distribution of functional traits in an assemblage, is critical for managing landscapes for biodiversity and ecosystem functions. Despite some scattered evidence, we lack a clear understanding of how patterns of fragmentation drive changes in functional diversity, and its relationship with species richness as habitat is lost from a landscape. Objectives: To develop testable predictions about how landscape fragmentation, relative to the effects of habitat loss, impacts functional diversity and its relationship with species richness. Methods: We used a spatially explicit metacommunity model that evaluates communities that vary in the distribution of response traits (traits involved in species responses to environmental change) and the correlation between response and effect traits (traits associated with species' effects on ecosystem functioning). Results: Compared to effects of habitat loss, relative effects of fragmentation on functional diversity increased as the variance in the distribution of response traits was high and the correlation among traits was high. Functional richness decreased faster than species richness in highly fragmented landscapes as habitat was lost. However, functional diversity remained unchanged or even increased in fragmented landscapes when either response and effect traits were not correlated (or weakly correlated), or when the proportion of generalist species with high dispersal capacities was high. Conclusions: Compared to effects of habitat loss, the relative effects of fragmentation on functional diversity and species richness are more dependent on the type of community evaluated. A careful evaluation of the variance in the distribution of response traits within a community, as well as the correlation among response and effect traits, can help to determine when it is important to manage landscape fragmentation to protect functional diversity. [ABSTRACT FROM AUTHOR]

Context: The role of protected areas as biodiversity repositories has become increasingly important in face of increased deforestation. By adding free-living exotic mammals, removing forest-dependent native ones, isolating forest patches from large protected areas and reducing landscape forest cover, human activities may drive mammal communities towards regional biotic homogenization. Objectives: We assessed how landscape forest cover and proximity to the largest and best-preserved area of the Catimbau National Park—one of the largest protected areas of the Brazilian Caatinga—affect α- and β-diversity of medium- and large-sized mammals, considering native and exotic species. Methods: Using camera traps (total effort of 2340 cameras/day), we obtained 823 records of 15 species (8 natives and 7 exotics) in 18 landscapes of 1-km radius. We estimated diversity metrics within and among landscapes and used generalized linear models to assess the effect of forest loss and isolation on diversity metrics. Results: As expected, forest loss decreased α-diversity of native species and increased the diversity and relative abundance of exotics. However, proximity to the preserved area showed weak effect on α-diversity, suggesting that this area does not work regionally as source for natives neither as ecological trap for exotics. Supporting the biotic homogenization hypothesis, β-diversity of natives decreased and β-diversity of exotics increased in more deforested landscapes. Yet, species composition was weakly related to forest cover and isolation. Conclusions: Our findings demonstrate that deforestation jeopardizes native species, favors exotics, and drives mammal communities towards biotic homogenization. Protected areas should be properly implemented to safeguard mammal diversity. [ABSTRACT FROM AUTHOR]

Context: Connectivity, which is a fundamental aspect of any landscape, has been shown to have a nonlinear relationship with the amount of natural habitat, with a marked decrease at intermediate levels of coverage. Impacts on connectivity vary according to how natural habitat is removed. We analyzed connectivity in the Brazilian Cerrado (tropical savanna), a 2 million-km2 biodiversity hotspot. Objectives: We evaluated the effects of habitat removal on connectivity, hypothesizing that a deforestation threshold exists below which connectivity is drastically reduced and that neighboring landscapes have similar patterns of connectivity. Methods: We divided the Cerrado into 624 50 × 50 km cells and used the integral index of connectivity (IIC), available in Conefor software, to evaluate changes in connectivity between 2000 and 2017. We analyzed how the intra, flux, and connector components of connectivity vary with changes in percentage of remaining natural habitat. Results: Between 2000 and 2017, 23.9% of the natural habitat of the Cerrado was lost (~ 254,000 km2) and connectivity decreased significantly (W = 179,700, p < 0.01). The most crucial change was the removal of connector fragments or corridors, which occurred in 78.2% of the landscapes. The relationship between IIC and remaining natural area revealed a breakpoint, when native area in a landscape reached 39% in 2000 and 37% in 2017. Conclusions: Regardless of the spatial arrangement of habitat fragments, landscape connectivity is lost when the remaining natural habitat falls below a certain threshold. More restrictive regulations and government permissions should be considered to avoid over-occupation of landscapes. [ABSTRACT FROM AUTHOR]

Context: Small fragments of natural habitats with an increased proportion of edges are common landscape traits following agricultural expansion. Consequences of habitat fragmentation are widely documented. However, functional and mechanistic approaches are still needed in order to understand these changes.Objectives: We studied habitat loss and edge effects on ant communities, addressing changes in species and functional group diversity, and the relative importance of β-diversity components.Methods: In an endangered Neotropical forest, we sampled ants in edge and interior habitats using pitfall traps, during three summers (28 sites). We calculated taxonomic, phylogenetic and functional diversity and partitioned taxonomic and functional β-diversity into replacement and loss/gain components.Results: We found more species and functional groups at edge than interior habitats, and four species were edge indicators. Habitat loss negatively affected total abundance and that of particular functional groups (fungus-growers and cryptic species) but had a positive effect on taxonomic, phylogenetic and functional diversity as well as abundance of opportunists and predators. Species and functional group replacement drove β-diversity, being linked to habitat loss. However, interactions between habitat loss and edges explained the loss/gain of taxonomic and functional composition.Conclusions: Fragmentation led to enriched ant communities at edges, possibly resulting from a higher influx of matrix species as edges become pervasive. This highlights the need to assess the spillover between habitats to understand its influence. Moreover, species replacement and the decrease of functional groups due to habitat loss could have an impact on ecosystem processes in which ants play an important role. [ABSTRACT FROM AUTHOR]

Context: Biodiversity is modulated by the spatial structure of the landscape. Thus, landscape metrics can be useful indicators of biota integrity and vulnerability, helping in conservation and management decisions.Objective: We performed the first quantitative analysis of the spatial structure of the Caatinga drylands. We estimated the habitat amount and the fragmentation pattern of this region using a multi-scale perspective.Methods: Using the Brazilian official database of native remnants, we calculated the number and percentage of remaining fragments per size class and we describe how habitat amount changes along the landscape. By simulating different dispersal capacities, we estimated the functional connectivity among remnants. We also calculated the cumulative core area as a function of different edge effect widths.Results: Caatinga is subdivided into 47,100 fragments. Although 91% of them are smaller than 500 ha, 720 fragments are larger than 10,000 ha, corresponding to 78% of the remaining vegetation. Potentially, 95% of the vegetation is accessible to species that can cross 1000 m of matrix. With one kilometer of edge effect, the core area is reduced to a quarter of the remaining vegetation. The habitat amount analyzes reinforced the regional differences in the spatial distribution of the remnants.Conclusions: Caatinga remains well connected for species with moderate and high dispersal capacities. However much of its remaining area is vulnerable to anthropogenic disturbances. Expansion of the protected area network and effective natural resource management to avoid overexploitation of the remnants are key strategies for maintaining the Caatinga biodiversity and its services. [ABSTRACT FROM AUTHOR]

Large-scale ecological networks (ENs) are an important mitigation measure in agriculturally transformed landscapes. However, understanding the multitude of pressures influencing the presence/absence of species, and subsequent degree of species spatial heterogeneity, is important when planning effective ENs. We aim here to measure these pressures and determine species heterogeneity in ENs against natural reference sites. We use arthropods, as they are effective bioindicators for measuring these pressures and heterogeneity, as many are habitat sensitive. Here we use many arthropod taxa to determine how a suite of variables influences the spatially sensitive grassland interior species of both EN corridors and protected areas (PAs). At each of 48 selected sites, nine stations were sampled for arthropods, with six stations in plantation block (i.e. transformed grassland) or natural indigenous forest, as well as associated edge zone and three stations in EN corridor or PA interior. Eleven variables were measured and classed into environmental, design, and current and historical management variables. Data were split into: overall data, recording all species found in interior zones, and datasets containing only species that had >50 or >75 % of their abundance sampled in the interior zone. These datasets were split into total species and singleton-removed datasets. Overall, the richness of non-singleton species, i.e. those frequently sampled in grassland interiors, were most responsive to natural background environmental variables, while design and management variables were most important for datasets with singletons retained. This means that when planning ENs, we first need to conserve the natural range of environmental heterogeneity to conserve a range of interior specialists. This natural spatial heterogeneity then needs to be incorporated into design and management planning to conserve the full range of biodiversity in ENs, as if in PAs. [ABSTRACT FROM AUTHOR]