Landscape composition is the strongest determinant of bird occupancy patterns in tropical forest patches     

Morante-Filho  José Carlos  Benchimol  Maíra  Faria  Deborah 《Landscape Ecology》2021,36(1):105-117

Context

Biodiversity in tropical region has declined in the last decades, mainly due to forest conversion into agricultural areas. Consequently, species occupancy in these landscapes is strongly governed by environmental changes acting at multiple spatial scales.

Objectives

We investigated which environmental predictors best determines the occupancy probability of 68 bird species exhibiting different ecological traits in forest patches.

Methods.

We conducted point-count bird surveys in 40 forest sites of the Brazilian Atlantic forest. Using six variables related to landscape composition and configuration and local vegetation structure, we predicted the occupancy probability of each species accounting for imperfect detections.

Results

Landscape composition, especially forest cover, best predicted bird occupancy probability. Specifically, most bird species showed greater occupancy probability in sites inserted in more forested landscapes, while some species presented higher occurrence in patches surrounded by low-quality matrices. Conversely, only three species showed greater occupancy in landscapes with higher number of patches and dominated by forest edges. Also, several species exhibited greater occupancy in sites harbouring either larger trees or lower number of understory plants. Of uttermost importance, our study revealed that a minimum of 54% of forest cover is required to ensure high (> 60%) occupancy probability of forest species.

Conclusions

We highlighted that maintaining only 20% of native vegetation in private property according to Brazilian environmental law is insufficient to guarantee a greater occupancy for most bird species. We recommend that policy actions should safeguard existing forest remnants, expand restoration projects, and curb human-induced disturbances to minimise degradation within forest patches.

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Responses of Chilean forest birds to anthropogenic habitat fragmentation across spatial scales   总被引：1，自引：1，他引：0  

Pablo M. Vergara  Juan J. Armesto 《Landscape Ecology》2009,24(1):25-38

Although it is recognized that anthropogenic forest fragmentation affects habitat use by organisms across multiple spatial scales, there is uncertainty about these effects. We used a hierarchical sampling design spanning three spatial scales of habitat variability (landscape > patch > within-patch) and generalized mixed-effect models to assess the scale-dependent responses of bird species to fragmentation in temperate forests of southern Chile. The abundances of nine of 20 bird species were affected by interactions across spatial scales. These interactions resulted in a limited effect of within-patch habitat structure on the abundance of birds in landscapes with low forest cover, suggesting that suitable local habitats, such as sites with dense understory cover or large trees, are underutilized or remain unused in highly fragmented landscapes. Habitat specialists and cavity-nesters, such as tree-trunk foragers and tapaculos, were most likely to exhibit interactions across spatial scales. Because providing additional sites with dense understory vegetation or large habitat trees does not compensate the negative effect of the loss of forest area on bird species, conservation strategies should ensure the retention of native forest patches in the mixed-use landscapes.  相似文献   

Post-disturbance recovery of forest cover and tree height differ with management in Central Europe     

Senf  Cornelius  Müller  Jörg  Seidl  Rupert 《Landscape Ecology》2019,34(12):2837-2850

Context

Recovery from disturbances is a prominent measure of forest ecosystem resilience, with swift recovery indicating resilient systems. The forest ecosystems of Central Europe have recently been affected by unprecedented levels of natural disturbance, yet our understanding of their ability to recover from disturbances is still limited.

Objectives

We here integrated satellite and airborne Lidar data to (i) quantify multi-decadal post-disturbance recovery of two indicators of forest structure, and (ii) compare the recovery trajectories of forest structure among managed and un-managed forests.

Methods

We developed satellite-based models predicting Lidar-derived estimates of tree cover and stand height at 30 m grain across a 3100 km² landscape in the Bohemian Forest Ecosystem (Central Europe). We summarized the percentage of disturbed area that recovered to >?40% tree cover and >?5 m stand height and quantified the variability in both indicators over a 30-year period. The analyses were stratified by three management regimes (managed, protected, strictly protected) and two forest types (beech-dominated, spruce-dominated).

Results

We found that on average 84% of the disturbed area met our recovery threshold 30 years post-disturbance. The rate of recovery was slower in un-managed compared to managed forests. Variability in tree cover was more persistent over time in un-managed forests, while managed forests strongly converged after a few decades post-disturbance.

Conclusion

We conclude that current management facilitates the recovery of forest structure in Central European forest ecosystems. However, our results underline that forests recovered well from disturbances also in the absence of human intervention. Our analysis highlights the high resilience of Central European forest ecosystems to recent disturbances.

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Primary productivity in cities and their influence over subtropical bird assemblages     

《Urban Forestry & Urban Greening》2017

Changes in ecosystem structure caused by urbanization produce a reduction in photosynthetic productivity, which can lead to reductions in resource availability for birds. Here, we analyzed the relation between photosynthetic productivity and bird assemblages in a subtropical urban ecosystem, in North-Western Argentina. We used Generalized Linear Models to assess the responses of bird abundance, richness and diversity to photosynthetic productivity, vegetation cover and distance to main natural forest. We found higher bird richness and diversity with increasing photosynthetic productivity and vegetation cover, and with decreasing distance to forests; while total bird abundance was positively related to vegetation cover. When we classified bird species in different groups, based on their use of the environment, we found that species adapted to urban environments were more dependent on photosynthetic productivity, while species related to native forests were more dependent on the distance to source forests. Understanding the factors that affect bird assemblages in cities is important for the development of strategies for urban planning and conservation.  相似文献   

Forest proximity rather than local forest cover affects bee diversity and coffee pollination services     

González-Chaves  Adrian  Jaffé  Rodolfo  Metzger  Jean Paul  de M. P. Kleinert  Astrid 《Landscape Ecology》2020,35(8):1841-1855

Context

As agricultural demands for land continues to expand, strategies are urgently needed to balance agricultural production with biodiversity conservation and ecosystem service provision in agricultural landscapes.

Objectives

We used a factorial landscape design to assess the relative contributions of forest proximity and local forest cover to bee diversity and the provision of coffee pollination services.

Methods

We quantified bee diversity and fruit set in 24 sun-grown coffee fields in Southeast Region of Brazil that were selected following a factorial sampling design to test the independent effects of local forest cover (in a radius of 400 m) and proximity to forest fragments. To assess the impact of landscape simplification, we also evaluated local coffee cover.

Results

Bee richness and abundance were higher in the proximity of forest fragments, but only bee abundance decreased when the coffee cover dominated the surrounding landscapes. Coffee fruit set was 16% higher overall with bee visitations compared with bee exclusion and increased to 20% when coffee bushes were near forest fragments, and the coffee cover was low. Surprisingly, local forest cover did not affect the bee community or coffee fruit set.

Conclusion

Our results provide clear evidence that the proximity of coffee crops to forest fragments can affect the abundance and richness of bees visiting the coffee flowers and thereby facilitate the provision of pollination services. The positive association between forest proximity and fruit set reinforces the importance of natural vegetation in enhancing bee diversity and, therefore, in the provision of pollination services. The negative effect of coffee cover on fruit set at the local scale suggests that the service demand can surpass the capacity of pollinators to provide it. These effects were independent of the local forest cover, although all studied landscapes had more than 20% remaining forest cover (within a 2 km radius), which is considered the extinction threshold for Atlantic Forest species. Interspersion of forest fragments and coffee plantations in regions with more than 20% of forest cover left could thus be a useful landscape management target for facilitating pollinator flows to coffee crops and thus for increasing coffee yields.

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Fine-scale characterization of bird habitat using airborne LiDAR in an urban park in Japan     

《Urban Forestry & Urban Greening》2016

Birds are ecosystem service providers and excellent urban ecosystem indicators because they are sensitive to habitat structure. Light detection and ranging (LiDAR) technology is a promising tool in bird habitat characterization because it can directly acquire fine-scale 3-D information over large areas; however, most of past avian ecological studies using LiDAR were conducted in North America and Europe, and there have been no studies in Asia. The robustness of LiDAR data across different habitat types remain problematic. In this study, we set 13 plots having different canopy area percentages in a large-scale urban park in Japan, and examined the usefulness of airborne LiDAR data in modeling richness and diversity of forest bird species and the abundance of Paridae species that play an important role in the urban food web. Bird surveys were conducted eight times at each plot during the birds’ breeding season, and the results were estimated using generalized linear models. In consequence, all of the response variables were explained by one or a few LiDAR variables, and the 1 × 1 × 1-m voxel-based variables were especially robust estimators. When targeting only densely-forested plots having more than 60% canopy area, the LiDAR data efficiency declined in estimation of the richness and diversity of whole forest bird species, whereas a laser penetration rate was efficient for estimating the Paridae species abundance. These results implied that the LiDAR data are useful in habitat characterization of forest birds, and even when targeting only dense forests, some LiDAR variables are effective for habitat estimation of birds preferring specific forest structures. In the future, application of LiDAR across a variety of ecosystems will greatly serve to develop adaptive conservation and management planning for urban forests.  相似文献   

The importance of native valley oaks (Quercus lobata) as stopover habitat for migratory songbirds in urban Sacramento,California, USA     

《Urban Forestry & Urban Greening》2018

Urban development occupies over 375,000 ha (6%) of California's Central Valley, and expansion continues to displace natural and agricultural landscapes. The value of urban areas as habitat for native wildlife and the characteristics that determine its value, however, remain little studied. Many Neotropical migrant passerine bird species are declining due to changes in breeding, migratory, and wintering habitats and climatic conditions. During 2010–2013, we evaluated the importance of native valley oak (Quercus lobata) as stopover foraging habitat used by Neotropical migrant birds in urban areas of the Sacramento region in California, USA. Over 3 years, we surveyed spring and late summer-early fall migrant songbirds and measured tree canopy cover within 31 c.0.91 ha transects in Curtis Park, an older residential neighborhood. We detected 607 individuals from 20 migrant species, but four wood warblers comprised the bulk of observations: black-throated gray (Setophaga nigrescens), Wilson's (Cardellina pusilla), orange-crowned (Oreothlypis celata), and yellow warblers (Setophaga petechia). Migrant abundance was closely correlated with valley oak canopy abundance and increased linearly with oak canopy especially during fall migration. Migrants were nearly absent from areas lacking oak canopy. Migrant bird species as a group also foraged in valley oak substantially more often (74%) than would be expected based on its 15% relative canopy cover (χ²_1d.f. = 924, p < 0.0001), as did all species whose selectivity could be tested. These results are important in demonstrating previously undocumented migrant use of urban areas with remnant valley oak canopy and suggest that protecting existing valley oaks and increasing their use in future urban forestry and landscape plantings in the Central Valley could provide substantial habitat benefits for native migratory birds.  相似文献   

The use of metapopulation and optimal foraging theories to predict movement and foraging decisions of mobile animals in heterogeneous landscapes     

Piotr Skórka  Magdalena Lenda  Rafał Martyka  Stanisław Tworek 《Landscape Ecology》2009,24(5):599-609

Metapopulation and optimal foraging theories predict the presence of animals and their duration, respectively, in foraging patches. This paper examines use of these two theories to describe the movements and patterns of foraging in patches used by Caspian gulls (Larus cachinnans) at inland reservoirs during the chick-rearing period. We assumed that birds would move differently across diverse habitats, with some types of land cover less permeable than others, and some landscape features acting as corridors. We also expected larger and less isolated patches, and patches that were close to corridors, to have a higher probability of the presence of foraging birds, and that they would be more abundant, forage for a shorter time, and hunt smaller prey than in small, more isolated patches surrounded by barriers. Forests seem to be a much less permeable type of land cover, whereas rivers became corridors for Caspian gulls during foraging trips. Probability of bird presence was positively related to the size of foraging patches and negatively linked with distance to the nearest river, distance to the nearest foraging patch, and the presence of forests in the vicinity. The same factors significantly affected bird abundance. Contrary to expectations, the duration and success of foraging were not influenced by any variable we measured, suggesting that although larger patches contain a higher abundance of fish, their density and the probability of capturing prey were relatively stable among the various patches. However, gulls that foraged in more isolated ponds that were located further from the river and the colony, and also surrounded by forest, captured larger fish more often than birds that foraged near the colony in less-isolated patches. Pooling metapopulation and optimal foraging concepts seems to be valuable in describing patch use by foraging animals. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

Using binary and probabilistic habitat availability indices derived from graph theory to model bird occurrence in fragmented forests     

Marcelo Awade  Danilo Boscolo  Jean Paul Metzger 《Landscape Ecology》2012,27(2):185-198

Loss of connectivity is one of the main causes of decreases in habitat availability and, thus, in species abundance and occurrence in fragmented landscapes. It is therefore important to measure habitat connectivity for conservation purposes, but there are several difficulties in quantifying connectivity, including the need for species movement behavioral data and the existence of few consistent indices to describe such data. In the present study, we used a graph theoretical framework to measure habitat availability, and we evaluate whether this variable is adequate to explain the occurrence pattern of an Atlantic rainforest bird (Pyriglena leucoptera, Thamnophilidae). The playback technique was used to parameterize the connectivity component of habitat availability indices and to determine the presence or absence of the study species in forest patches. Patch- and landscape-level habitat availability indices were considered as explanatory variables. Two of these were landscape-level indices, which varied in terms of how inter-patch connections are defined, using either a binary or probabilistic approach. This study produced four striking results. First, even short open gaps may disrupt habitat continuity for P. leucoptera. Second, the occurrence of P. leucoptera was positively affected by habitat availability. Third, proper measures of this explanatory variable should account for the landscape context around the focal patch, emphasizing the importance of habitat connectivity. Finally, habitat availability indices should consider probabilistic and not binary inter-patch connections when intending to explain the occurrence of bird species in fragmented landscapes. We discuss some conservation implications of our results, stressing the advantages of an ecologically scaled graph theoretical framework.  相似文献   

Bird response to disturbance varies with forest productivity in the northwestern United States     

David B. McWethy  Andrew J. Hansen  Jake P. Verschuyl 《Landscape Ecology》2010,25(4):533-549

Huston’s Dynamic Equilibrium Hypothesis predicts that the response of biodiversity to disturbance varies with productivity. Because disturbance is thought to break competitive advantage of dominant species in productive ecosystems, species richness is predicted to increase with disturbance frequency in productive systems. Recovery of plant biomass following disturbance is also predicted to be faster in productive systems. Here we provide the first test of Huston’s hypothesis in the context of setting harvest rates in managed forests for achieving biodiversity objectives. We examined predictions relating to vegetation and bird response to disturbance and succession in productive and less productive forests in western Oregon and Washington, USA. We found that measurements of understory cover and shrub diversity were higher in young, productive stands than less productive stands of similar age. Later-seral forests in productive environments (mean age = 67 years) had less variable and more complete canopy closure than similar-age forests in less favorable settings. At the stand scale, bird abundance and richness decreased with canopy closure in highly productive forests whereas bird abundance and richness increased with canopy closure in less productive forests. At the landscape scale, bird abundance and richness within stands increased with increasing levels of disturbance in the surrounding landscape within highly productive forests, whereas bird abundance and richness decreased with increasing disturbance in the surrounding landscape within less productive forests. Our results indicate that bird response to disturbance varies across levels of productivity and suggest that bird species abundance and associated species richness will be maximized through relatively more frequent disturbance in highly productive systems.  相似文献   

The scale of saproxylic beetles response to landscape structure depends on their habitat stability     

Percel  Gwendoline  Laroche  Fabien  Bouget  Christophe 《Landscape Ecology》2019,34(8):1905-1918

Context

Forest management and disturbances cause habitat fragmentation for saproxylic species living on old-growth attributes. The degree of habitat spatiotemporal continuity required by these species is a key question for designing biodiversity-friendly forestry, and it strongly depends on species’ dispersal. The “stability–dispersal” model predicts that species using stable habitats should have lower dispersal abilities than species associated with ephemeral habitat and thus respond to habitat availability at smaller scales.

Objectives

We aimed at testing the stability–dispersal model by comparing the spatial scales at which saproxylic beetle guilds using substrates with contrasted stability (from stable to ephemeral: cavicolous, fungicolous, saproxylophagous and xylophagous guilds) are affected by landscape structure (i.e. habitat amount and aggregation).

Methods

We sampled saproxylic beetles using a spatially nested design (plots within landscape windows). We quantified habitat availability (tree cavities, polypores and deadwood) in 1-ha plots, 26-ha buffers around plots and 506-ha windows, and analyzed their effect on the abundance and diversity of associated guilds.

Results

The habitat amount within plots and buffers positively affected the abundance of the cavicolous and the fungicolous guilds whereas saproxylophagous and xylophagous did not respond at these scales. The habitat aggregation within windows only positively affected the saproxylophagous species richness within plots and also on the similarity in species composition among plots.

Conclusions

Beetle guilds specialized on more stable habitat were affected by landscape structure at smaller spatial scales, which corroborated the stability–dispersal model. In managed forests, the spatial grain of conservation efforts should therefore be adapted to the target habitat lifetime.

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Rural depopulation and recent landscape changes in a Mediterranean region: Consequences to the breeding avifauna   总被引：8，自引：0，他引：8  

Eric Preiss  Jean-Louis Martin  Max Debussche 《Landscape Ecology》1997,12(1):51-61

We studied the vegetational and avifaunistic changes following rural depopulation in an area covering 2,600 ha north of Montpellier (Southern France). The study area is covered by a mosaic of Mediterranean habitats that includes cultivation, grasslands, shrublands, and woodlands and is representative of the natural features present and of the human usage practiced so far in this part of the Mediterranean. We sampled the vegetation and the bird fauna in the same 193 census plots in 1978 and in 1992. At both the habitat and landscape scales the cover of woody plants increased significantly. Open habitats tend to disappear. As a consequence the abundance of open-habitat bird species decreased significantly whereas the abundance of forest birds increased significantly. These changes favor a pool of forest species widespread in western Europe and reduce habitat availability for open habitat and shrubland species. Many of the latter are Mediterranean species whose distribution in Western Europe could become reduced under current landscape dynamics. Our observation of more woodlands and their typical birds and of less open habitats and their associated avifauna is not consistent with the traditional worry shown by the public and the managers about the regression of forests and woodlands in the Northern Mediterranean as a consequence of fire.  相似文献   

Weak effects of farming practices corresponding to agricultural greening measures on farmland bird diversity in boreal landscapes     

Ekroos  Johan  Tiainen  Juha  Seimola  Tuomas  Herzon  Irina 《Landscape Ecology》2019,34(2):389-402

Context

The current Common Agricultural Policy (CAP) of the European Union includes three greening measures, which are partly intended to benefit farmland biodiversity. However, the relative biodiversity effects of the greening measures, including joint effects of landscape context, are not well understood.

Objectives

We studied the effects of increasing crop diversity, proportions of production grasslands and fallows, corresponding to CAP greening measures, on open farmland bird diversity, whilst controlling for the effects of distance to forests, field edge density and proportion of built-up areas.

Methods

We surveyed open farmland birds using territory mapping in Southern Finland. We modelled effects of greening measures and landscape structure on farmland birds (7642 territories) using generalised linear mixed models.

Results

Increasing proportions of grasslands increased farmland bird species richness and diversity in open farmland, whereas increasing proportions of fallows increased bird diversity. Increasing crop diversity benefited individual species, but not species richness or diversity. Increasing field edge densities consistently increased the species richness of all farmland species, in-field nesters and non-crop nesters, as well as total farmland bird diversity. The relative effect of edge density was much stronger compared to the three greening measures.

Conclusions

Our results show that promoting fallows and grasslands, in particular grazed grasslands and various types of semi-natural grasslands, has the highest potential to benefit farmland bird diversity. Maintaining or increasing field edge densities, currently not supported, seems to be of even more benefit. In open farmland, with little or no field edges, fallows and grasslands are particularly beneficial.

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Habitat and food supply across multiple spatial scales influence the distribution and abundance of a nocturnal aerial insectivore     

Philina A. English  Joseph J. Nocera  Bruce A. Pond  David J. Green 《Landscape Ecology》2017,32(2):343-359

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Modeling a cross-ecosystem subsidy: forest songbird response to emergent aquatic insects     

Schilke  Paul R.  Bartrons  Mireia  Gorzo  Jessica M.  Vander Zanden  M. Jake  Gratton  Claudio  Howe  Robert W.  Pidgeon  Anna M. 《Landscape Ecology》2020,35(7):1587-1604

Context

Resource movements across ecosystem boundaries are important determinants of the diversity and abundance of organisms in the donor and recipient ecosystem. However the effects of cross-ecosystem movements of materials at broader spatial extents than a typical field study are not well understood.

Objectives

We tested the hypotheses that (1) variation in abundance of 57 forest songbird species within four foraging guilds is explained by modeled emergent aquatic insect biomass inputs from adjacent lakes and streams and (2) the degree of association varies across foraging guilds and species within guilds. We also sought to determine the importance of emergent aquatic insects while accounting for variation in local forest cover and edge.

Methods

We spatially modeled the degree to which distribution and abundance of songbirds in different foraging guilds was explained by modeled emergent aquatic insect biomass. We used multilevel models to simultaneously estimate the responses of species in four different insectivorous guilds. Bird abundance was summarized from point counts conducted over 24 years at 317 points.

Results

Aerial insectivores were more abundant in areas with high estimated emergent insect biomass inputs to land (regression coefficient 0.30, P?<?0.05) but the overall abundance of gleaners, bark-probers, and ground-foragers was not explained by estimated emergent insect abundance. The coursing aerial insectivores had the strongest association with emergent insects followed by willow flycatcher, olive-sided flycatcher, and alder flycatcher.

Conclusions

Modeling cross-ecosystem movements of materials at broad spatial extents can effectively characterize the importance of this ecological process for aerial insectivorous songbirds.

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Vertebrate distributions relative to clear-cut edges in a boreal forest landscape   总被引：5，自引：0，他引：5  

Lennart Hansson 《Landscape Ecology》1994,9(2):105-115

Clearcutting is the main method of harvesting boreal forests, to some extent mimicking natural disturbances by fire and wind-felling. Effects of clearcutting on vertebrate fauna in managed forests was examined by small mammal trapping in spring and autumn, winter censuses of mammal snow tracks and censuses of birds in spring and summer in one central and one edge (125 m) section of large clearcuts and mature forests, respectively. There was a separate clearcut fauna, at least on large clearcuts, that was well distinguished from the forest fauna. There was not any physiognomic ecotone but the forest fauna showed a marked edge effect with larger numbers of many species in the peripheral parts of the forest. In the forests examined, with a Western European bird fauna, there were no typical interior forest species, in contrast to northern taiga forests. The present forest species easily changed distributions seasonally and according to variations in snow conditions and food abundance. Such generalist species in the boreal forest will therefore vary considerably in local density according to landscape composition but will also show large-scale persistence. They may have been selected for as a result of man's restructuring of temperate and boreal landscapes, e.g. by forest management. Edge effects seem to arise for several reasons but will probably only apply to generalist species.  相似文献   

Spatial patterns of bird community similarity: bird responses to landscape composition and configuration in the Atlantic forest     

Gustavo A. Zurita  M. Isabel Bellocq 《Landscape Ecology》2010,25(1):147-158

Studies dealing with community similarity are necessary to understand large scale ecological processes causing biodiversity loss and to improve landscape and regional planning. Here, we study landscape variables influencing patterns of community similarity in fragmented and continuous forest landscapes in the Atlantic forest of South America, isolating the effects of forest loss, fragmentation and patterns of land use. Using a grid design, we surveyed birds in 41 square cells of 100 km² using the point count method. We used multivariate, regression analyses and lagged predictor autoregressive models to examine the relative influence of landscape variables on community similarity. Forest cover was the primary variable explaining patterns of bird community similarity. Similarity showed a sudden decline between 20 and 40% of forest cover. Patterns of land use had a second order effect; native bird communities were less affected by forest loss in landscapes dominated by tree plantations (the most suitable habitat for native species) than in landscapes dominated by annual crops or cattle pastures. The effects of fragmentation were inconclusive. The trade-off between local extinctions and the invasion of extra-regional species using recently created habitats is probably the mechanism generating the observed patterns of community similarity. Limiting forest loss to 30–40% of the landscape cover and improving the suitability of human-modified habitats will contribute to maintain the structure and composition of the native forest bird community in the Atlantic forest.  相似文献   

Edge effect of low-traffic forest roads on bird communities in secondary production forests in central Europe     

Miroslav Šálek  Jana Svobodová  Petr Zasadil 《Landscape Ecology》2010,25(7):1113-1124

Worldwide forests fragmentation has lead to a massive increase of habitat edges, creating both negative and positive impacts on birds. While busy highways dissecting forested areas create edges which are known to reduce bird densities due to the disturbing effect of noise, the impacts of logging forest roads with low traffic volumes have rarely been studied. In this study, we compared species richness and similarity of canopy, cavity and shrub guilds of birds along low-traffic forest roads, in forest interior, and at forest edges in secondary forests in central Europe, where the forests have passed through extensive changes toward uniformly compact growths dominated by production conifers. Although we found tree diversity as positively affecting bird richness across all habitats, the bird richness along forest roads was higher than in forest interior but lower than along forest edges. The shrub guild of birds along forest roads resembled this guild along forest edges while canopy and cavity guilds at the roads were more similar to these guilds in forest interior. Forest interior had the highest probability for some guild to be absent. We conclude that low-traffic roads lead to increase of habitat heterogeneity in structurally poor forests and attract birds due to additional habitat attributes—including better light conditions—that are scarce in forest interior. Therefore, broader support for higher structural diversification of uniform plantations in central European production forests would benefit bird communities inhabiting these areas.  相似文献   

Nonparametric machine learning for mapping forest cover and exploring influential factors     

Liu  Bao  Gao  Lei  Li  Baoan  Marcos-Martinez  Raymundo  Bryan  Brett A. 《Landscape Ecology》2020,35(7):1683-1699

Context

The contribution of forest ecosystem services to human well-being varies over space following the dynamics in forest cover. Use of machine learning models is increasing in projecting forest cover changes and investigating the drivers, yet references are still lacking for selecting machine learning models for spatial projection of forest cover patterns.

Objectives

We assessed the ability of nonparametric machine learning techniques to project the spatial distribution of forest cover and identify its drivers using a case study of Tasmania, Australia.

Methods

We developed, evaluated, and compared the performance of four nonparametric machine learning models: support vector regression (SVR), artificial neural networks (ANN), random forest (RF), and gradient boosted regression trees (GBRT).

Results

The results demonstrated that RF far outperformed the other three models in both fitting and projection accuracy, and required less computional costs. GBRT outperformed SVR and ANN in projection accuracy. However, RF exhibited serious overfitting due to the full growth of its decision trees. The influence rankings of explanatory variables on spatial patterns of forest cover were different under the four models. Land tenure type and rainfall were identified among the top four most influential variables by all four models. The ranking produced by the RF model was significantly different with topographic factors associated with land clearing and production costs (elevation and distance to timber facilities) being the two most influential variables.

Conclusions

We encourage practitioners to consider nonparametric machine learning methods, especially RF, when facing problems of complex environmental data modelling.

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Effects of land use legacies and habitat fragmentation on salamander abundance     

Bradley J. Cosentino  Kristen M. Brubaker 《Landscape Ecology》2018,33(9):1573-1584

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