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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]

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]

• A novel mathematical and computational model of biological invasion has been developed. • We have investigated how a road can impact the propagation of invasive plant species. • The growth function is the main factor determining the spread of the invasive species. Invasive plant species pose a significant threat to biodiversity and the economy, yet their management is often resource-intensive and expensive, and further research is required to make control measures more efficient. Evidence suggests that roads can have an important effect on the spread of invasive plant species, although little is known about the underlying mechanisms at play. We have developed a novel mathematical model to analyse the impact of roads on the propagation of invasive plants. The integro-difference equation model is formulated for stage-structured population and incorporates a road sub-domain in the spatial domain. The results of our study reveal, that, depending on the definition of the growth function in the model, there are three distinct types of behaviour in front of the road. Roads can act as barriers to invasion, lead to a formation of a beachhead in front of the road, or act as corridors allowing the invasive species to invade the domain in front of the road. Analytical and computational findings on how roads can impact the spread of invasive species show that a small change in conditions of the environment favouring the invasive species can change the case for the road, allowing the invasive species to invade the domain in front of the road where it previously could not spread. [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., Competing Interests: No competing interests were disclosed., (Copyright: © 2023 Gervais L et al.)

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., Competing Interests: Daniel de Paiva Silva is an Academic Editor for PeerJ., (© 2022 Teixeira et al.)