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Understanding the propagation of invasive plants at the beginning of invasive spread is important as it can help practitioners eradicate harmful species more efficiently. In our work the propagation regime of the invasive plant species is studied at the short-time scale before a travelling wave is established and advances into space at a constant speed. The integro-difference framework has been employed to deal with a stage-structured population, and a short-distance dispersal mode has been considered in the homogeneous environment and when a road presents in the landscape. It is explained in the paper how nonlinear spatio-temporal dynamics arise in a transient regime where the propagation speed depends on the detection threshold population density. Furthermore, we investigate the question of whether the transient dynamics become different when the homogeneous landscape is transformed into the heterogeneous one. It is shown in the paper how invasion slows down in a transient regime in the presence of a road. [ABSTRACT FROM AUTHOR]

To investigate whether trees and palms scattered in pastures contribute to the maintenance of bat assemblages in landscapes highly fragmented by livestock farming activities, we evaluated the bat assemblages and foraging guilds between wooded pastures and riparian vegetation. Using mist nets, we captured 1013 bats from 29 species and four taxonomic families. We found that the abundance, richness, and composition of bat species were not significantly different between vegetation types. Frugivores were the most abundant guild, and their abundance did not differ between vegetation types, indicating that wood-pastures allow the presence of these bats in the landscape. On the other hand, insectivores were more abundant in riparian vegetation and, interestingly, nectarivores were more abundant in pastures, likely due to the great plasticity of species of the genus Glossophaga. Our results are encouraging, since they demonstrate that a rustic pasture management that promoting the presence of scattered trees and palms along with belts of riparian vegetation, allows the maintenance of bat assemblages in a highly fragmented landscape. [ABSTRACT FROM AUTHOR]

Context: Most tropical forest landscapes are highly fragmented, have habitat patches varying in size and shape, and display different degrees of perturbation, but with high conservation values. Therefore, a major goal of landscape ecology is to discover the actual spatial scale at which landscape composition and structure affect biological processes and biodiversity. Objective: This study aimed to determine the landscape scale of effect governing the α and β diversities of woody species in a highly fragmented, semideciduous tropical forest. Methods: We recorded the diversity of woody species in 19 plots scattered across a highly fragmented, semideciduous tropical forest landscape. Then, we used CART algorithms to evaluate the effects of landscape attributes on the α and β diversities of such species across 100 scales (10–1000 m) and tested continuous effects with generalized additive models. Results: The shape and size of habitat patches in the range of 250–470 m determined α diversity. As for β diversity, nestedness was affected by the shape of forest patches at 510 m, whereas landscape heterogeneity affected species turnover within 100 m buffers. Conclusion: While a previous study in a similar habitat reported effects at 800 m, the number, size, and shape of habitat patches in the current study accounted for the diversity of the focal plots within 100–510 m. Furthermore, CART effectively screened 100 scales, revealing which landscape attributes correlated the most with the diversity of woody plants. The findings provide valuable guidelines for conservation, restoration efforts, and public policies. [ABSTRACT FROM AUTHOR]

In agricultural landscapes, patches containing diverse species can serve as nodes, and species diffusion among these patches can serve as edges, forming metapopulation networks. However, the impact of landscape fragmentation on these networks and consequences for keystone crop species remain unclear. Here, we investigated thrips (pests) and lacewings (natural predators) in mango orchards and surrounding habitats across 15 landscapes. Using a machine learning neural network, we built metapopulation networks for thrips and lacewings based on the relationship between patch properties and species abundance. We evaluated these networks with metrics like clustering coefficient, strength, and path length. Furthermore, we analyzed the effects of landscape fragmentation, as indicated by edge density and landscape Shannon diversity, on network structures and the subsequent effect on species abundance using piecewise structural equation modeling. The results show that the neural network effectively constructed the metapopulation network, accurately predicting lacewing and thrips abundance in various patches with an accuracy rate exceeding 80%. Positive correlations were observed between edge density and network strength for both species. However, a positive relationship between landscape Shannon diversity and network path length was identified only for lacewings. Edge density had a greater impact on lacewings and thrips compared to landscape Shannon diversity, with a negative effect on lacewings and a positive effect on thrips. Edge density affected lacewing abundance both directly and indirectly through network strength. However, no network structure mediated the effect of landscape fragmentation on thrips abundance. Our conclusion highlights that the effects of landscape fragmentation on species are primarily driven by edge effects. These effects were clarified by the metapopulation network structure, which varied depending on the species. The findings provide new perspectives on metapopulation networks to unlock the landscape fragmentation effects.

Herein, we investigated the genetic diversity and population structure of Euglossa cordata L., an orchid bee species widely distributed at the heterogeneous set of vegetal physiognomies encompassed in a transition zone (TZ) of different Brazilian biomes. We then tested whether phytogeographic regions would play some rule for the genetic diversity. Results revealed that only 12 and 28 out 78 pairs of samples showed some degree of genetic structure for microsatellites (FST≤ 0.029; Dest≤0.091; p < 0.05) and mtDNA(0.138 ≤mt-ϕST≤ 0.495; p < 0.05) markers, respectively. We found evidence of two and three genetic clusters in nuclear and mtDNA markers, but no significant structure based on phytogeographic regions or geographic distances. These findings point out that local idiosyncrasies and historic factors, but not different types of vegetation or geographic distances drive the patterns of the observed genetic structure. Drops in the diversity index and other estimators highlight that E. cordata may have experienced some local bottlenecks despite its resilience to anthropic interferences. These are the first records of relatively high genetic structure in E. cordata populations and have important implications for orchid bees' conservation. [ABSTRACT FROM AUTHOR]

Context: Animal movement through the landscape is essential to several ecological processes, assuring genetic flow, reproductive success and population dynamics. In fragmented landscapes, species change their movement patterns according to their sensitivity to landscape cover and configuration. Increased landscape habitat loss and fragmentation affects resource distribution and habitat availability, compelling species to move more frequently through anthropized matrices. Objectives: Our aim was to provide a new prospect for what is known about animal movement through the landscape anthropogenic matrix in the Atlantic Forest biodiversity hotspot, by analyzing the potential movement distances of several mammal, bird, reptile, and amphibian species. Methods: We used recorded roadkills within the Brazilian Atlantic Forest as a source of information of species' occurrence. We assumed the euclidean distance from the roadkill spot to the nearest forest fragment as the potential movement distance by different species through the anthropogenic matrix. Experts' classification of species' forest dependence degree, and animal movement information from the literature survey was used to analyze the variation in potential animal movement distance in these matrices. Results: We analyzed 90 species, the majority of them being non-forest dependent (n = 64; 71%). The potential movement distances ranged from 0 to > 1500 m, and forest-dependent species presented lower mean distances (between 772 and 978 m) than non-forest dependent species (between 673 and 1015 m). The literature survey resulted in 44 articles regarding animal movement in the matrix, referred only to 22 species. No articles were found for 20 species, mainly reptiles and amphibians. Conclusions: By comparing these values to the average distance between forest remnants in the Atlantic Forest, we expect that the distance to be traveled through the matrix to reach forest fragments may be restrictive, mainly for species with higher degree of forest dependence. Despite being descriptive, our results provide important insights on animal movement through the matrix, especially for less studied species, such as amphibians and reptiles. [ABSTRACT FROM AUTHOR]

Fragmentation and scale: Although habitat loss has well‐known impacts on biodiversity, the effects of habitat fragmentation remain intensely debated. It is often argued that the effects of habitat fragmentation, or the breaking apart of habitat for a given habitat amount, can be understood only at the scale of entire landscapes composed of multiple habitat patches. Yet, fragmentation also impacts the size, isolation and habitat edge for individual patches within landscapes. Addressing the problem of scale on fragmentation effects is crucial for resolving how fragmentation impacts biodiversity. Scaling framework: We build upon scaling concepts in ecology to describe a framework that emphasizes three "dimensions" of scale in habitat fragmentation research: the scales of phenomena (or mechanisms), sampling and analysis. Using this framework, we identify ongoing challenges and provide guidance for advancing the science of fragmentation. Implications: We show that patch‐ and landscape‐scale patterns arising from habitat fragmentation for a given amount of habitat are fundamentally related, leading to interdependencies among expected patterns arising from different scales of phenomena. Aggregation of information when increasing the grain of sampling (e.g., from patch to landscape) creates challenges owing to biases created from the modifiable areal unit problem. Consequently, we recommend that sampling strategies use the finest grain that captures potential underlying mechanisms (e.g., plot or patch). Study designs that can capture phenomena operating at multiple spatial extents offer the most promise for understanding the effects of fragmentation and its underlying mechanisms. By embracing the interrelationships among scales, we expect more rapid advances in our understanding of habitat fragmentation. [ABSTRACT FROM AUTHOR]

Habitat loss is often considered the greatest near‐term threat to biodiversity, while the impact of habitat fragmentation remains intensely debated. A key issue of this debate centers on the problem of scale–landscape or patch–at which to assess the consequences of fragmentation. Yet patterns are often confounded across scales, and experimental designs that could solve this scaling problem remain scarce. We conducted two field experiments in 30 experimental landscapes in which we manipulated habitat loss, fragmentation, and patch size for a community of four insect herbivores that specialize on the cactus Opuntia. In the first experiment, we destroyed 2088 Opuntia patches in either aggregated or random patterns and compared the relative effects of landscape‐scale loss and fragmentation to those of local patch size on species occurrence. This experiment focused on manipulating the relative separation of remaining patches, where we hypothesized that aggregated loss would disrupt dispersal more than random loss, leading to lower occurrence. In the second experiment, we destroyed 759 Opuntia patches to generate landscapes that varied in patch number and size for a given amount of habitat loss and assessed species occurrence. This experiment focused on manipulating the subdivision of remaining habitat, where we hypothesized that an increase in the number of patches for a given amount of loss would lead to negative effects on occurrence. For both, we expected that occurrence would increase with patch size. We find strong evidence for landscape‐scale effects of habitat fragmentation, with aggregated loss and a larger number of patches for a given amount of habitat loss leading to a lower frequency of patches occupied in landscapes. In both experiments, occurrence increased with patch size, yet interactions of patch size and landscape‐scale loss and fragmentation drove species occurrence in patches. Importantly, the direction of effects were consistent across scales and effects of patch size were sufficient to predict the effects of habitat loss and fragmentation across entire landscapes. Our experimental results suggest that changes at both the patch and landscape scales can impact populations, but that a long‐standing pattern—the patch‐size effect—captures much of the key variation shaping patterns of species occurrence. [ABSTRACT FROM AUTHOR]

Wildlife in Southeast Asia is greatly affected by agricultural expansion. While intensive farming causes biodiversity decline, low-intensive farming can support some adapted wildlife. In Thailand, the rapid transformation of forests to agricultural landscapes over three decades has resulted in large forest and biodiversity loss, with several Endangered species suffering from cropland expansion. Among these, the Green Peafowl, an Endangered Galliformes widely distributed across Southeast Asia, has shown the capacity to adapt well to low-intensive agriculture landscapes by using crops as food sources. Here we investigated in detail the Green Peafowl’s habitat use in an agricultural landscape surrounding a large forest patch composed of three protected areas in northern Thailand. Using line transect surveys and compositional analysis, we estimated the monthly Peafowl use of different crop types and different crop structures between January 2020 and January 2021. The Green Peafowl’s habitat use was significantly non-random. The order of habitat preference was timber plantations > orchards > cropland > fallow land. The species also preferred cropland within a 500 m buffer zone around the forest patch. The species preferred crops with a canopy structure (timber and orchards) that resembles their natural habitat. Our results confirm that low-intensive and diversified agricultural landscapes could help to sustain the Green Peafowl population. Importantly, we also show that closed canopy crops, such as large tree plantations like teak, rubber and orchards, can provide good alternatives for reforestation to reconnect forest fragments and isolated patches in highly degraded habitats as they allow the species to move further away from forest edges within the degraded landscape.

Context: Prairies historically covered much of inland North America, and many species have adapted to the unique conditions found in prairie ecosystems. Less than 1% of prairies remain in Arkansas, with much historic prairie having been converted for urban and agricultural development, resulting in steep population declines for many prairie-associated species. Objectives: Because many reptile and amphibian species are difficult to detect, the current distributions and habitat requirements of prairie-associated herpetofauna in fragmented landscapes are poorly understood. Thus, we assessed the state of prairie-associated herpetofauna communities in intact prairie, as well in degraded and developed historic prairie throughout Western Arkansas. Methods: Using repeated field surveys, remote sensing data, and hierarchical community occupancy models, we examined the influence of vegetation conditions, land use, and landscape characteristics on an assemblage of nine species of prairie-associated herpetofauna. Results: Prairie mound density, representing prairie that has not been subject to intense anthropogenic disturbance, was the strongest positive predictor of occupancy by prairie-associated species. Historic prairie area also exhibited a positive relationship with occupancy for several species but not at the assemblage level. Current vegetation conditions did not strongly influence occupancy patterns. Conclusions: Our results suggest that long-term land use filters, rather than present site-level conditions, are the driving forces dictating current distributions of prairie-associate herpetofauna in Western Arkansas. Our findings provide insight into the present state of understudied populations in an increasingly fragmented region and present accessible tools for directing exploratory conservation and research efforts. [ABSTRACT FROM AUTHOR]

Background: In contrast with historical knowledge, a recent view posits that a non-negligible proportion of populations thrive in a fragmented landscape. One underlying mechanism is the maintenance of functional connectivity, i.e., the net flow of individuals or their genes moving among suitable habitat patches. Alternatively, functional connectivity might be typically limited but enhanced by a higher reproductive success of migrants. Methods: We tested for this hypothesis in wild snapdragon plants inhabiting six patches separated by seawater in a fragmented Mediterranean scrubland landscape. We reconstructed their pedigree by using a parentage assignment method based on microsatellite genetic markers. We then estimated functional connectivity and the reproductive success of plants resulting from between-patch dispersal events. Results: We found that wild snapdragon plants thrived in this fragmented landscape, although functional connectivity between habitat patches was low (i.e. 2.9%). The progeny resulting from between-patch dispersal events had a higher reproductive success than residents. Conclusion: Our findings imply that low functional connectivity in a fragmented landscapes may have been enhanced by higher reproductive success after migration. This original mechanisms might be partly compensating the negative impact of fragmentation.

Tropical forest loss has been a prominent concern in Madagascar, portrayed by a highly fragmented landscape of forests surrounded by small-scale agricultural patches along the northwestern and eastern regions. This paper seeks to identify priority areas for forest landscape restoration at a landscape scale using a geospatial land suitability analysis approach. The study area is the watershed of Mahavavy, home to one of the most biodiverse ecosystems in the island but also an important agriculture region. The suitability analysis method comprises five major steps: (1) the identification of a set of restoration criteria, (2) the acquisition of available environmental datasets for each criterion, (3) generating suitability maps for each criterion, (4) the conception of a suitability analysis model, and (5) the design of potential sites for restoration. The specific suitability criteria combine both landscape composition and soil characteristics, including (i) distance from protected sites and forest patches, (ii) land cover classes, (iii) distance from settlements, (iv) distance from roads, (v) risk of soil erosion. We found 143,680 ha (27.9%) that were highly suitable areas for forest landscape restoration, 159127 (30.9%) moderately suitable and138031 ha (26.6%) not suitable areas. High potential suitable areas are observed in close proximity of forest patches and protected areas, and low restoration feasibility in all areas that are easily accessible and thus subjected to exploitation. [ABSTRACT FROM AUTHOR]

Aim: How β‐diversity patterns are shaped by landscape‐level processes remains unclear across habitat island systems. Here we assessed landscape‐level bird β‐diversity in habitat island systems and aimed to (1) evaluate the relative contribution of turnover (βSIM) and nestedness‐resultant (βSNE) components to multisite β‐diversity (βSOR) from taxonomic, functional and phylogenetic dimensions; (2) examine the influence of climate factors and system characteristics in shaping landscape‐level patterns of β‐diversity measures; and (3) study how β‐diversity patterns of bird communities vary with the spatial extents of island systems. Location: Global. Taxon: Birds. Methods: We compiled bird data in 22 habitat island systems from literature and classified these island systems into small and large spatial scales. We partitioned βSOR into βSIM and βSNE from three dimensions for each system and calculated standardized functional and phylogenetic β‐diversity measures. We assessed the effects of climate factors and system characteristics on observed and standardized β‐diversity measures by multiple linear models for both small and large systems. Results: We found that the dominant role of βSIM to βSOR in habitat island systems was pervasive. However, the best explanatory variables were not consistent across systems, which depended on the β‐diversity components, diversity dimensions and spatial extent of habitat island systems. In general, climate factors acted as the main drivers of bird communities across small and large systems, whereas system characteristics played minor roles. Main conclusions: Spatial turnover dominated overall bird β‐diversity in most habitat island systems. Our results imply the roles of niche‐based assembly processes through the interplay among differential functional traits and phylogenetic distances of species, climate factors and system characteristics as well as spatial extent in driving bird communities across multiple habitat island systems at a landscape level. This study offers a better understanding of the processes underlying macroecological patterns of isolated biological communities across habitat island systems. [ABSTRACT FROM AUTHOR]

We report on new occurrence records of Lophostoma brasiliense Peters, 1867 (Chiroptera, Phyllostomidae) from the states of São Paulo and Mato Grosso do Sul, southeastern Brazil. Specimens from São Paulo were mist-netted in an area originally covered by the Atlantic Forest and Cerrado ecosystems of which only small and isolated fragments remain, while the specimens from Mato Grosso do Sul came from a well-preserved Cerrado area. The new records confirm the presence of L. brasiliense in the Brazilian state of São Paulo and clarify the southern edge of the species’ range.

The leading causes of the worldwide decline in biodiversity are global warming, allied with natural habitat loss and fragmentation. Here, we propose an analysis of the synergistic effects of these two factors in 63 species of Amazonian lizards. We predicted that the high-climatic suitability areas of species would be significantly impacted by different deforestation scenarios and the resultant landscape structure and considered that forest-dwelling species would be especially susceptible to deforestation scenarios. We also pointed out species threatened by both drivers and suggested critical areas for their future conservation. According to our results, most species will face future reductions in suitable areas for their occurrence according to five different patterns, two of which represent significant risks for 15 species. Some of these species already deal with severe habitat loss and fragmentation of their current distribution ranges, whereas others will suffer a considerable area reduction related to future range shifts. We emphasize the importance of protected areas (PAs), especially indigenous lands, and the need to plan combined strategies involving PAs' maintenance and possible implementation of ecological corridors. Finally, we highlight eight species of thermoconformer lizards that constitute present and future conservation concerns related to the combined effects of climate change and habitat loss and that should be carefully evaluated in extinction risk assessments. [ABSTRACT FROM AUTHOR]

The leading causes of the worldwide decline in biodiversity are global warming, allied with natural habitat loss and fragmentation. Here, we propose an analysis of the synergistic effects of these two factors in 63 species of Amazonian lizards. We predicted that the high-climatic suitability areas of species would be significantly impacted by different deforestation scenarios and the resultant landscape structure and considered that forest-dwelling species would be especially susceptible to deforestation scenarios. We also pointed out species threatened by both drivers and suggested critical areas for their future conservation. According to our results, most species will face future reductions in suitable areas for their occurrence according to five different patterns, two of which represent significant risks for 15 species. Some of these species already deal with severe habitat loss and fragmentation of their current distribution ranges, whereas others will suffer a considerable area reduction related to future range shifts. We emphasize the importance of protected areas (PAs), especially indigenous lands, and the need to plan combined strategies involving PAs’ maintenance and possible implementation of ecological corridors. Finally, we highlight eight species of thermoconformer lizards that constitute present and future conservation concerns related to the combined effects of climate change and habitat loss and that should be carefully evaluated in extinction risk assessments.

Introduction: Dung beetles perform important functions in terrestrial ecosystems, but anthropic pressures affect them negatively. These effects are well documented in neotropical lowland forests but have been studied little in Andean forests. Objective: To evaluate how the attributes of the dung beetle assemblages and three of their ecological functions differ in three types of vegetation cover, and to determine the relationships between attributes and functions, and among functions. Methods: Dung beetles were captured with pitfall traps, and ecological functions were measured through a field experiment in the farm “El Ocaso” (Colombia), in three types of vegetation cover: secondary forest, mixed forest and cattle pasture (three independent sites per cover). The assemblage attributes that were evaluated were abundance, number of species, biomass, and weighted mean body length; functions measured were dung removal, soil excavation, and secondary seed dispersal. Results: It was found that both the assemblage attributes and the ecological functions were negatively affected in the more disturbed vegetation covers, particularly in cattle pastures. Most of the assemblage attributes correlated positively with functions; soil excavation and secondary seed dispersal had a strong positive correlation with dung removal. Conclusions: Dung beetle assemblages play important ecological functions and they are sensitive to ecosystem disturbances. This study shows how dung beetles and their functions are affected negatively when forest is transformed to cattle pasture in the understudied and highly fragmented Andean forest ecosystems. [ABSTRACT FROM AUTHOR]

For situations and crops as diverse as sugarcane in Réunion (a French overseas department), grown in systems close to monoculture, and cotton in Cameroon, grown in rotation with food crops, the gruelling manual weed control operations using hoes (the daba in Cameroon and the mattock in Réunion), traditionally inherent to family farming, have been considerably alleviated by the emergence then widespread implementation of chemical weed control, manual in Cameroon and partially motorised in Réunion. Based on these two examples taken from his experience as a tropical agronomist in Northern Cameroon and in Réunion, the author concludes that in just a few decades, family farming and chemical weed control have forged very strong links, which are now difficult to undo.

For situations and crops as diverse as sugarcane in Réunion (a French overseas department), grown in systems close to monoculture, and cotton in Cameroon, grown in rotation with food crops, the gruelling manual weed control operations using hoes (the daba in Cameroon and the mattock in Réunion), traditionally inherent to family farming, have been considerably alleviated by the emergence then widespread implementation of chemical weed control, manual in Cameroon and partially motorised in Réunion. Based on these two examples taken from his experience as a tropical agronomist in Northern Cameroon and in Réunion, the author concludes that in just a few decades, family farming and chemical weed control have forged very strong links, which are now difficult to undo. [ABSTRACT FROM AUTHOR]

Studying how habitat loss affects the tolerance of ecological networks to species extinction (i.e. their robustness) is key for our understanding of the influence of human activities on natural ecosystems. With networks typically occurring as local interaction networks interconnected in space (a meta‐network), we may ask how the loss of specific habitat fragments affects the overall robustness of the meta‐network. To address this question, for an empirical meta‐network of plants, herbivores and natural enemies we simulated the removal of habitat fragments in increasing and decreasing order of area, age and connectivity for plant extinction and the secondary extinction of herbivores, natural enemies and their interactions. Meta‐network robustness was characterized as the area under the curve of remnant species or interactions at the end of a fragment removal sequence. To pinpoint the effects of fragment area, age and connectivity, respectively, we compared the observed robustness for each removal scenario against that of a random sequence. The meta‐network was more robust to the loss of old (i.e. long‐fragmented), large, connected fragments than of young (i.e. recently fragmented), small, isolated fragments. Thus, young, small, isolated fragments may be particularly important to the conservation of species and interactions, while contrary to our expectations larger, more connected fragments contribute little to meta‐network robustness. Our findings highlight the importance of young, small, isolated fragments as sources of species and interactions unique to the regional level. These effects may largely result from an unpaid extinction debt, whereby younger fragments are likely to lose species over time. Yet, there may also be more long‐lasting effects from cultivated lands (e.g. water, fertilizers and restricted cattle grazing) and network complexity in small, isolated fragments. Such fragments may sustain important biological diversity in fragmented landscapes, but maintaining their conservation value may depend on adequate restoration strategies. [ABSTRACT FROM AUTHOR]

According to the island syndrome and island rule hypotheses, island isolation and reduced area lead to phenotypic shifts in ecologically relevant traits in insular populations compared to mainland ones. These hypotheses have been built up with oceanic islands in mind or islands where isolation is high and colonization rate relatively limited. This set of hypotheses, however, may not be applicable to other inland–island systems or recently fragmented landscapes. We investigated how island life leads to phenotypic changes in two rodent metapopulations: deer mice and red‐backed voles in a fragmented system on a river in Canada. From 2013 to 2016, we sampled 454 deer mice and 665 red‐backed voles spread across 10 islands and six mainland sites on river shores. We compared body mass, tail and hindfoot length, exploration and reaction towards predators, between individuals from island and mainland sites, and assessed the role of connectivity, isolation and area of islands. Insular individuals from both species were less aggressive towards potential predators and insular mice were more thorough explorers compared to mainland ones. Male mice were heavier and juvenile mice had longer tails on islands. However, contrary to expectations, we found negative relationships between aggressiveness and juvenile exploration score with patch connectivity for mice. Island connectivity significantly affected tail length of mice through a concave relationship. Finally, vole aggressiveness and exploration of male mice were positively correlated to island isolation. Our study supports only partially the predictions of the island syndrome hypothesis. It provides empirical evidence that inland–island life can modify traits in deer mice, but less so in red‐backed voles in a non‐oceanic system. It also raises questions about the direct causal factors of these changes in a naturally fragmented landscape, and urges for more predictive models about phenotypic/genetic divergence among populations in natural and artificial fragmented landscapes. [ABSTRACT FROM AUTHOR]

Ecosystem functions provided by forests are threatened by direct and indirect effects of global change drivers such as climate warming land‐use change, biological invasions, and shifting natural disturbance regimes. To develop resilience‐based forest management, new tools and methods are needed to quantitatively estimate forest resilience to management and future natural disturbances. We propose a multidimensional evaluation of ecological resilience based on species functional response traits (e.g., functional response diversity and functional redundancy) and network properties of forested patches (e.g., connectivity, modularity, and centrality). Using a fragmented rural landscape in temperate south‐eastern Canada as a reference landscape, we apply our multidimensional approach to evaluate two alternative management strategies at three levels of intensity: (1) functional enrichment of current forest patches and (2) multi‐species plantations in previously non‐forested patches. Within each management strategy, planted species are selected to maximize functional diversity, drought tolerance, or pest resistance. We further compare how ecological resilience under these alternative management strategies responds to three simulated disturbances: drought, pest outbreak, and timber harvesting. We found that both management strategies enhance resilience at the landscape scale by increasing functional response diversity and connectivity. Specifically, when the less functionally diverse patches are prioritized for management, functional enrichment is more effective than the establishment of new multi‐species plantations in increasing resilience. In addition, randomly allocated multi‐species plantations increased connectivity more than those allocated in riparian areas. Our results show that across various management strategies, planting species to enhance biodiversity led to the highest increase in functional response diversity while planting pest‐resistant species led to the highest increase in landscape connectivity. Planting biodiversity‐enhancing species (i.e., species that maximize functional diversity) mitigated drought effects equally well as planting with drought‐tolerant species. Our multidimensional approach facilitates the characterization at the landscape scale of forest resilience to disturbances using both functional diversity and network properties while accounting for the importance of response traits to future disturbances. The simulation approach we used can be applied to forest landscapes across different biomes for the evaluation and comparison of forest management initiatives to enhance resilience. [ABSTRACT FROM AUTHOR]

Species with vast production of dust‐like windborne seeds, such as orchids, should not be limited by seed dispersal. This paradigm, however, does not fit recent studies showing that many sites suitable for orchids are unoccupied and most seeds land close to their maternal plant. To explore this issue, we studied seed dispersal and gene flow of two forest orchid species, Epipactis atrorubens and Cephalanthera rubra, growing in a fragmented landscape of forested limestone hills in southwest Bohemia, Czech Republic.We used a combination of seed trapping and plant genotyping methods (microsatellite DNA markers) to quantify short‐ and long‐distance dispersal, respectively. In addition, seed production of both species was estimated.We found that most seeds landed very close to maternal plants (95% of captured seeds were within 7.2 m) in both species, and dispersal distance was influenced by forest type in E. atrorubens. In addition, C. rubra showed clonal reproduction (20% of plants were of clonal origin) and very low fruiting success (only 1.6% of plants were fruiting) in comparison with E. atrorubens (25.7%). Gene flow was frequent up to 2 km in C. rubra and up to 125 km in E. atrorubens, and we detected a relatively high dispersal rate among regions in both species.Although both species occupy similar habitats and have similar seed dispersal abilities, C. rubra is notably rarer in the study area. Considerably low fruiting success in this species likely limits its gene flow to longer distances and designates it more sensitive to habitat loss and fragmentation. [ABSTRACT FROM AUTHOR]

The American bullfrog Lithobates catesbeianus has a natural distribution in North America, but was spread by human activities in different regions around the world. It is listed as the most invasive amphibian species, affecting terrestrial and aquatic ecosystems and the community of native species. In addition, the American bullfrog is extensively associated with lethal pathogens, with high correlation of the presence of this species with population declines and extinctions. Here we test if this alien species has spread through the landscape, establishing populations at new locations. We used diverse methods including georeferencing of satellite images, ethnobiological interviews and field data to evaluate the dispersion and effects of L. catesbeianus introduction on amphibian composition, species number, and density of individuals in forest fragments in an Atlantic Forest landscape. We did not find any relationship between density of individuals, number of species or composition of the native anuran assemblages in forest fragments in relation to the presence or proximity of American bullfrog introduction points. Additionally, we found that the dispersion potential of this species in the studied landscape is zero, as it was only found in those fragments where it was specifically introduced 15 years ago. The species has not established new populations in the landscape. Although exotic, L. catesbeianus thrives in lentic habitats and has no apparent effect on the structural metrics of the native anuran assemblage. Despite this alien species exhibiting a capacity to adapt and survive at the point of introduction, its potential for propagation is limited probably by the fragmented terrestrial landscape and regional stream network. [ABSTRACT FROM AUTHOR]

Urbanisation is seen as one of the most important drivers for species extinction. The aim of our study was to compare vascular plant species richness of 35 artificial urban stormwater ponds (STOPON) designed to control water flow, with 35 control ponds (CONTROL) in the surrounding landscape. For both plot types, we gathered a variety of environmental parameters to determine the drivers of plant species richness. Based on the results, we discuss the relevance of STOPON for biodiversity conservation in urban areas and give recommendations for biodiversity-friendly construction and pond management. Our study showed that the environmental conditions clearly varied between STOPON and CONTROL. STOPON were especially larger than CONTROL; as a consequence, the aquatic, semi-aquatic and terrestrial zones had a greater extent at STOPON. Accordingly, the overall and mean number of aquatic, salt-tolerating aquatic and threatened plant species was higher at STOPON than at CONTROL. However, species density of all three plant indicator groups did not differ among the two plot types. The greater plant species richness of STOPON was driven by a higher habitat heterogeneity which was especially explained by (i) the genuine effect of habitat area on habitat heterogeneity, (ii) the existence of three similarly large habitat zones (terrestrial, semi-aquatic, aquatic) and (iii) the regular management, which represses shading plants, creates open soil and activates the soil seed bank. Due to the high species richness of threatened plant species STOPON play an important role in biodiversity conservation in urban areas. [ABSTRACT FROM AUTHOR]

Fire is an intrinsic component of many natural ecosystems. In human‐modified landscapes that occur in fire‐driven ecosystems, it can be difficult to make fire management decisions, as there must be a trade‐off between ideal conservation management and the practicalities of management in an altered landscape.We assess how biodiversity is influenced by differences in fire regime in a landscape fragmented by timber production. Here, optimal fire management for maintaining grassland integrity is not always possible, due to logistical constraints and fire risk to plantations. We investigate thicket establishment arising from reduced fire frequency, and how this affects butterfly diversity, assemblage structure, indicator species and species associations to larval host plants with different growth forms. Butterflies were sampled along a gradient of woodiness in large‐scale conservation corridors that separate timber compartments.The two extreme stages along the successional gradient, recently burned grassland and natural forests, supported relatively diverse and complementary butterfly assemblages. Grassland corridors without fire for 2 years were as high in butterfly diversity and similar in composition to recently burned grasslands. However, corridors without fire for >5 years were encroached by thicket and supported lower butterfly diversity. Thicket, with its intermediate vegetation character, was poor habitat for species adapted to either open grassland or to forests. Also, thicket‐encroached areas carry high fire risk to plantations.Synthesis and applications. In this fragmented, fire‐driven ecosystem, there is more than one burning strategy for achieving positive biodiversity outcomes. We recommend a divergent management approach that covers both extremes of the fire frequency continuum, with the choice depending on the stage of succession and management logistics for each site: (a) frequent burning to prevent woody encroachment in less‐encroached, logistically easier sites or (b) letting succession run its course through thicket to forest by excluding fire in heavily encroached, logistically challenging sites. Both options are practicable and maintain biotopes that have high value for butterfly conservation and low fire risk to plantations. This divergent management approach is a flexible strategy that benefits both conservation and commercial interests across fire‐prone plantation mosaics. In this fragmented, fire‐driven ecosystem, there is more than one burning strategy for achieving positive biodiversity outcomes. We recommend a divergent management approach that covers both extremes of the fire frequency continuum, with the choice depending on the stage of succession and management logistics for each site: (a) frequent burning to prevent woody encroachment in less‐encroached, logistically easier sites or (b) letting succession run its course through thicket to forest by excluding fire in heavily encroached, logistically challenging sites. Both options are practicable and maintain biotopes that have high value for butterfly conservation and low fire risk to plantations. This divergent management approach is a flexible strategy that benefits both conservation and commercial interests across fire‐prone plantation mosaics. [ABSTRACT FROM AUTHOR]

Land-use change has caused degradation, loss and fragmentation of semi-natural habitats, especially in grassland ecosystems. Today, the remaining habitats are often situated in a matrix of intensively used agricultural land and are therefore more or less isolated from each other. Connectivity, area and quality of habitat patches have been identified as the most important drivers for the persistence of grassland specialists living in metapopulations. However, the relative importance of these factors is still under debate. We used a large-scale, multi-taxon approach to obtain a general pattern which would facilitate conservationists to promote many, instead of one, species. We studied the patch occupancy of 13 grassland specialists belonging to three different insect orders within a Central European landscape with 89 fragments of calcareous grasslands. To disentangle the relative importance of the three metapopulation parameters, generalized linear models (GLM) and variation-partitioning techniques were used. Our study revealed that habitat quality was the most important factor determining the occurrence of specialized species, followed by habitat area. In comparison to habitat connectivity, the variance explained by habitat quality was significantly higher across the studied species. Nevertheless, the persistence of at least six model organisms depended on the degree of habitat connectivity. We conclude that maintaining a high habitat quality on large patches should be the first choice for the conservation of habitat specialist insects in fragmented landscapes. As a secondary measure, conservationists should concentrate on the restoration of relict sites. This increases not only the habitat area, but also contributes to better habitat connectivity. [ABSTRACT FROM AUTHOR]

The loss of global biodiversity is one of the major challenges of our time and urbanisation is seen as a main cause of this. The aim of this study was to determine whether artificial stormwater ponds, designed to control water flow, can act as refuges for Odonata in urban areas. Moreover, we analysed the influence of habitat and landscape quality on dragonfly species richness and density of 35 stormwater ponds (STOPON) in comparison to 35 control ponds (CONTROL). Our study revealed significant differences in environmental conditions between STOPON and CONTROL. At the habitat level, STOPON were larger, had a warmer microclimate, and lower concentrations of phosphate. STOPON were predominantly situated in suburbs, while CONTROL occurred mostly in rural areas. Accordingly, at the landscape level, STOPON had greater cover of built-up area as well as a lower cover of arable land and woodland. In line with this, the dragonfly assemblages at STOPON and CONTROL differed. Overall species richness was greater at STOPON than at CONTROL, and indicator species were only identified for STOPON. Especially threatened species benefited from STOPON, having higher species richness as well as higher adult and exuviae densities than CONTROL. In conclusion, our study shows that stormwater ponds in urban areas play an important role in the conservation of dragonflies in general and threatened species in particular. At STOPON, as a result of regular management, the habitat quality was high and compensated for the low landscape quality stemming from significant urbanisation effects. [ABSTRACT FROM AUTHOR]

Urbanisation is one of the most severe drivers of current global biodiversity loss and has contributed to severe declines in many amphibian species. The aim of this study was to determine whether artificial stormwater ponds, designed to control water flow, can act as refuges for amphibians in urban areas. Moreover, we analysed the influence of habitat and landscape quality on amphibian species richness of 46 stormwater ponds (STOPON) in comparison to 46 control ponds (CONTROL). Our study revealed that environmental conditions clearly varied between STOPON and CONTROL. The most pronounced differences were that STOPON were larger, shallower, sunnier, more isolated by streets and had a greater cover of built-up area and lower cover of arable land surrounding them. Nevertheless, the amphibian assemblages of STOPON and CONTROL were very similar. All nine amphibian species (including three threatened species) detected in this study were found in both pond types. Moreover, species richness (2.8 ± 0.2 vs. 2.3 ± 0.2) and the frequency of each species did not differ between STOPON and CONTROL. The only exception was Pelophylax spp., which occurred more regularly in STOPON. Both habitat and landscape quality affected amphibian species richness; however, the explanatory power of the habitat models was about twice as high as those of the landscape models. In conclusion, stormwater ponds play an important role for amphibians in urban areas. In comparison to CONTROL, the low landscape quality in the surroundings of STOPON seemed to be compensated by a higher habitat quality due to regular management. [ABSTRACT FROM AUTHOR]

Landscape discontinuities such as forest edges play an important role in determining the characteristics of the atmospheric flow by generating increased turbulence and triggering the formation of coherent tree-scale structures. In a fragmented landscape, consisting of surfaces of different heights and roughness, the multiplicity of edges may lead to complex patterns of flow and turbulence that are potentially difficult to predict. Here, we investigate the effects of different levels of forest fragmentation on the airflow. Five gap spacings (of length approximately 5 h, 10 h, 15 h, 20 h, 30 h, where h is the canopy height) between forest blocks of length 8.7 h, as well as a reference case consisting of a continuous forest after a single edge, were investigated in a wind tunnel. The results reveal a consistent pattern downstream from the first edge of each simulated case, with the streamwise velocity component at tree top increasing and turbulent kinetic energy decreasing as gap size increases, but with overshoots in shear stress and turbulent kinetic energy observed at the forest edges. As the gap spacing increases, the flow appears to change monotonically from a flow over a single edge to a flow over isolated forest blocks. The apparent roughness of the different fragmented configurations also decreases with increasing gap size. No overall enhancement of turbulence is observed at any particular level of fragmentation. [ABSTRACT FROM AUTHOR]