The effects of urban or rural landscape context and distance from the edge on native woodland plant communities

The increasing rate of urban sprawl continues to fragment European landscapes threatening the persistence of native woodland plant communities. The dynamics of woodland edges depend on the characteristics of woodland patches and also on landscape context. Our aim was to assess the extent of edge influences on the understorey vegetation of small native woodlands in rural and urban landscapes. The study was carried out in two cities of north-western France. Ten comparable woodlands, each of about 1.5 ha, were surveyed; five were situated adjacent to crops and five adjacent to built-up land. Vascular plant species were recorded in 420 3 × 3 m plots placed at seven different distances from the edge (from 0 to about 45 m from the edge). Soil pH, light levels, level of disturbance and tree and shrub cover were also recorded. Plant species were first classified as non-indigenous or indigenous and then three groups of indigenous species were distinguished according to their affinity for forest habitat (forest specialists, forest generalists and non-forest species). We inferred certain ecological characteristics of understorey vegetation by using Ellenberg values. An inter-class correspondence analysis was carried out to detect patterns of variation in plant community composition. Linear mixed models were used to test the effects of adjacent land use, distance from the edge and their interactions on the species richness of the different groups and on the ecological characteristics of vegetation. Total species richness, richness of forest generalists and of non-forest species decreased from edge to interior in both urban and rural woodlands. The number of non-indigenous species depended mainly on urban–rural landscape context. Urban woodland edges were not as rich in forest specialists as rural edges. More surprisingly, the number of forest specialists was higher in rural edges than in rural interiors. Community composition was mainly affected by urban–rural context and to a lesser degree by the edge effect: the community composition of urban edges resembled that of urban interiors whereas in rural woodlands vegetation near edges (up to 10 m) strongly differed from interiors with a pool of species specific to edges. Urban woodland vegetation was more nitrophilous than rural vegetation in both edges and interiors. A major difference between urban and rural vegetation was the distribution of basiphilous species according to distance from the edge. Generally edge vegetation was more basiphilous than interior vegetation however the presence of basiphilous species fell off quickly with distance from the edge in rural woodlands (in the first 10–15 m) and more slowly (from 25 m onwards) in urban woodlands. This pattern was linked to variation in measured soil pH. As regards the conservation of flora in small native woodlands, it appeared that invasion of exotic and non-forest species was currently limited in both urban and rural landscape contexts but might pose problems in the future, especially in urban woodlands. Forest species were not negatively affected by the edge effect and indeed edges seemed to provide important habitats for this group. Hence conservationists should pay particular attention to the protection of edges in urban woodlands.     

Effects of wear and above ground forest site type characteristics on the soil microbial community structure in an urban setting

We studied the effects of wear on the understorey vegetation and the soil microbial community structure (phospholipid fatty acid pattern) in urban forests of medium fertility and of varying size in the capital area of Finland, Helsinki. These forests are important sites of recreation for a large number of residents. Consequently, the cover of understorey vegetation is affected by trampling. In the study, the cover of ground layer plant species (mosses) was found to be lower than in rural reference areas. We found that microbial activity, measured as soil respiration, was lower in the most worn forest patches as compared to less worn sites. Further, the microbial community structure of the humus layer changed due to the effects of wear. By comparing the PLFA pattern in trampled and un-trampled forest patches, we found out that the most important factors affecting the structure of microbial community were the dominant tree species (the proportion of broad-leaved tree species in relation to conifers), and the composition of the understorey vegetation. Thus, we could conclude that wear affects the microbial community structure through changes in vegetation, in the quality of litter shed, and through resultant changes in the humus pH, rather than only through soil compaction.     

Distribution and effects of tree leaf litter on vegetation composition and biomass in a forest-grassland ecotone

Aims After abandonment of grasslands, secondary succession leads to the invasion by woody species. This process begins with the accumulation of tree litter in the forest–grassland ecotone. Our objectives were to determine the relationships between litter amounts and vegetation composition and cover along natural forest–grassland ecotones and to experimentally study the initial effects of tree litter accumulation on grassland vegetation and on microsite conditions.Methods We established 11 transects varying from 12 to 15 m in length in different forest–grassland ecotones in the Lahn-Dill highlands, Germany, and measured the mass and cover of tree litter and the cover and composition of vegetation at five sequential positions along each transect by using 1 m 2 plots with five replications. In a field experiment, we established plots subjected to different litter amounts (0, 200 and 600g m ?2) and evaluated changes in grassland vegetation, soil temperature and soil nutrient availability below the litter layer.Important findings Tree litter amounts decrease from 650 to 65g m ?2 across the forest–grassland ecotone. Vegetation changed from shrubs and annual species (adapted to more stressful conditions) in the forests edge to grasses, rosettes and hemirosette species (with higher competitive abilities) in the grassland. These anthropogenic forest–grassland ecotones showed abrupt edges, and the two adjacent ecosystems were characterized by different species pools and functional groups. In the field experiment, the presence of a litter layer reduced vegetation biomass and cover; the species richness was only reduced in the treatment with high litter (600g m ?2). Additionally, adding litter on top of vegetation also reduced thermal amplitude and the number of frost days, while increasing the availability of some nutrients, such as nitrogen and aluminium, the latter being an indicator of soil acidification. Adding a tree litter layer of 600g m ?2 in grassland areas had strong effects on the composition and diversity of grassland vegetation by reducing the cover of several key grassland species. In, or near, forest edges, litter accumulation rapidly changes established vegetation, microsite conditions and soil nutrients.     

Overstorey Control of Understorey Species Composition in a Near-natural Temperate Broadleaved Forest in Denmark

Little is known about the importance of the forest overstorey relative to other factors in controlling the spatial variability in understorey species composition in near-natural temperate broadleaved forests. We addressed this question for the 19 ha ancient forest Suserup Skov (55°22′ N, 11°34′ E) in Denmark, one of the few old-growth temperate broadleaved forest remnants in north-western Europe, by inventorying understorey species composition and environmental conditions in 163 100 m² plots. We use unconstrained and constrained ordinations, variation partitioning, and Indicator Species Analysis to provide a quantitative assessment of the importance of the forest overstorey in controlling understorey species composition. Comparison of the gradients extracted by unconstrained and constrained ordinations showed that the main gradients in understorey species composition in our old-growth temperate broadleaved forest remnant are not caused by variability in the forest overstorey, but are related to topography and soil, edge effects, and unknown broad-scale factors. Nevertheless, overstorey-related variables uniquely accounted for 15% of the total explained variation in understorey species composition, with the pure overstorey-related (R_po), topography and soil (R_pt), edge and anthropogenic disturbance effects (R_pa), and spatial (R_ps) variation fractions being of equal magnitude. The forward variable selection showed that among the overstorey-related variables understorey light availability and to a lesser extent vertical forest structure were most important for understorey species composition. No unique influence of overstorey tree species identity could be documented. There were many indicator species for high understorey light levels and canopy gap centres, but none for medium or low light or closed canopy. Hence, no understorey species behaved as obligate shade plants. Our study shows that, the forest overstorey has a weak control of understorey species composition in near-natural broadleaved forest, in contrast to results from natural and managed forests comprising both conifer and broadleaved species. Nevertheless, >20% of the understorey species found were indicators of high light conditions or canopy openings. Hence, variability in canopy structure and understorey light availability is important for maintaining understorey species diversity.     

An experimental study of the impacts of understorey forest vegetation and herbivory by red deer and rodents on seedling establishment and species composition in Waitutu Forest, New Zealand

Introduced mammalian herbivores are changing the structure and composition of New Zealand’s forest ecosystems and may modify forest succession after natural disturbances. We studied how introduced ungulates (red deer and feral pigs) and rodents (rats and house mice) affected the rate of recovery (i.e. the engineering resilience) of the forest understorey following artificial disturbance. We imposed disturbances by clearing understorey vegetation dominated by Blechnum ferns in forests on relatively fertile alluvium and elevated infertile marine terraces, and recorded recovery of vegetation (seedling establishment, species composition, cover and volume) in herbivore exclosures and controls. Seedlings quickly established on cleared plots: after 2 years, numbers of woody seedlings and ground cover of vascular plants relative to initial values were similar on cleared and uncleared treatments. Volume of plant biomass <2 m remained low on cleared subplots. Ungulates significantly reduced the re-establishment of woody seedlings ≥ 10 cm tall: only one seedling reached this height outside exclosures, compared with 29 seedlings inside. The number of seedlings <10 cm tall, expressed relative to numbers present pre-clearing, was not significantly affected by ungulates. The species composition of regenerating vegetation was more similar (Jaccard index) to pre-clearing understorey vegetation inside ungulate exclosures than outside. No consistent effect of rodents (primarily house mice) on seedling establishment or species composition was detected after 2 years, and rodent exclosures did not significantly affect survival of seedlings (Griselinia littoralis and Aristotelia serrata) planted as an index of rodent herbivory pressure. No significant differences in vegetation recovery were apparent between forest types. Rapid seedling recruitment in the absence of understorey vegetation and the presence of herbivores provided evidence that understorey vegetation competes with seedlings for light. Ungulate effects were consistent with other experiments that showed herbivores reduced the rate and altered the trajectory of vegetation regrowth after disturbance.     

Effects of Severe Tropical Cyclone Larry on rainforest vegetation and understorey microclimate near a road,powerline and stream

Abstract Severe Tropical Cyclone Larry damaged a large swathe of rainforest to the west of Innisfail in north‐eastern Queensland on 20 March 2006. Within the path of the most destructive core of the cyclone were sites previously established along human‐made (powerlines and highways) and natural (streams) linear canopy openings for a study of edge effects on adjacent rainforest plant communities and associated microclimates. Vegetation damage and understorey microclimate parameters were measured 6 months after the passage of Cyclone Larry and compared with results before the cyclone. We examined the spatial patterns of vegetation damage in relation to natural and artificial linear clearing edges and the vegetation structural factors influencing these patterns as well as resulting alterations to microclimate regimes experienced in the rainforest understorey. Vegetation damage was spatially patchy and not elevated near linear clearing edges relative to the forest interior and did not differ between edge types. Vegetation damage was influenced, albeit relatively weakly, by structural traits of individual trees and saplings, especially size (diameter at breast height, d.b.h.) and successional status: tree damage was greater in pioneer species and in larger trees, while sapling damage was greater in canopy tree species than in understorey tree or shrub species. Changes in the understorey microclimate mirrored the degree of damage to vegetation. Where vegetation damage appeared greater, the understorey microclimate was brighter, warmer, drier and windier than below less‐damaged areas of the forest canopy. Overall, understorey light availability, wind speed and the diurnal ranges of air temperature and vapour pressure deficit increased dramatically after Cyclone Larry, while pre‐cyclone edge gradients in light availability were lost and temperature and vapour pressure deficit gradients were reversed.     

The Seedling Community of Tropical Rain Forest Edges and Its Interaction with Herbivores and Pathogens1

Edge effects alter biotic interactions and forest regeneration. We investigated whether edge creation affected the seedling community and its interactions with herbivores and leaf‐fungal pathogens. In forest edges and interior sites in Chiapas, Mexico, we counted all woody seedlings and species (10–100 cm tall) present in 1‐m² plots, measured their size (height and leaf number), and examined them for the occurrence of herbivory and pathogen damage. We investigated relationships between levels of damage and size, species richness and density. Species composition and biotic damage varied greatly among sites and habitats (edge vs interior). Late‐successional species dominated the community, but richness was lower in interior sites and species similarity was greater among edges than among interiors. Nearly all species (95%) present at edges and interiors showed herbivory damage, whereas 76 percent of the species in edge plots and 68 percent in interior plots showed pathogen damage. Although leaf area damaged by herbivores was similar between habitats (average 9.2%), pathogen damage was three times greater in edge plots (1.85%) than in interior plots (0.57%). Size was positively related to biotic damage at both habitats. Relationships between herbivory and pathogen damage and between pathogen damage and leaf number were significant only for edges. Biotic damage was not related to density or species richness. Overall, plant community structure was similar between habitats, but biotic damage was enhanced at edges. Thus, disease spread at edges may arise as a threat to tropical rain forest vegetation.     

Disturbance of suburban Fagus forests by recreational activities: Effects on soil characteristics,above‐ground vegetation and seed bank

Questions: How does recreational disturbance (human trampling) affect soil characteristics, the performance of the understorey vegetation, and the density and species composition of the soil seed bank in Fagus sylvatica forests? Location: Suburban forests near Basel, northwestern Switzerland. Methods: We compared various soil characteristics and the performance of the understorey vegetation in six beech forest areas frequently disturbed by recreational activities with those in six undisturbed control areas, in spring 2003. In the same forest areas, the soil seed bank was investigated using the seedling emergence method. Samples were obtained from soil cores in January 2003. Results: We found substantial changes in soil compaction, above‐ground vegetation and in the soil seed bank due to recreational activities. In frequently visited areas, soil compaction was enhanced which caused a decrease in cover, height and species richness of both herb and shrub layers. Compared with control areas, the number of trampling‐tolerant species of the seed bank was significantly higher in disturbed areas, and total species richness tended to be higher in disturbed than in control areas. Furthermore, the similarity in species composition between the above‐ground vegetation and seed bank was significant lower in disturbed than in control areas. Conclusions: The intensive use of suburban forests for recreational activities, mainly picnicking, affects the vegetation of natural beech forests. Our study indicates that a restoration of degraded forest areas from the soil seed bank would result in a substantial change of the vegetation composition.     

Effects of ski resort management on vegetation

We investigated species composition and characteristics of plant communities in plots at seven site types within a ski resort: forests, an abandoned ski slope, an area under the gondola lines, forest waterfronts, open waterfronts, edges of ski slopes, and an active ski slope. On the abandoned ski slope, under the gondola lines, at the edges of ski slopes, and on the ski slope, canopy closure was low, tall herbs were present, and species diversity was high. Some wetland species were present at waterfront plots. Differential species composition was caused by vegetation cutting, which was necessary to manage the ski resort. We found various plants, including herbs, some rarely seen because their habitats have decreased. Despite their negative effects, such as surface-soil erosion and magnification of plant size due to the use of ammonium sulfate, ski resorts can be important plant habitats with highly diverse species composition.     

Does the width of isolated ravine forests influence moss and liverwort diversity and composition?—A study of temperate forests in South Africa

The evidence of microclimatic edge effects through forest/open area ecotones is firm. How this affects the species composition near edges is less well understood and documented. In south-western South Africa shrub-dominated regularly burnt vegetation (i.e. fynbos) is the most common vegetation with indigenous temperate forests naturally occurring mostly in ravines on mountain slopes. The size and width of these forest patches varies considerably. In order to understand how the width of forest patches affects species composition of mosses and liverworts we investigated 20 forest patches of different width. In each forest patch we compiled a total species list, and collected data on selected environmental variables, for a plot of 10×20 m. No significant relationship was found between patch width and the number of either moss or liverwort species. However, the species composition of mosses (but not liverworts) changed along the gradient of patch width. The variation in number of species was large (8–29 mosses and 11–33 liverworts) among the plots and we propose that factors other than distance to the forest edge may be more important in structuring the bryophyte community of these ravine forests. One such factor that is likely to be important is the climatic difference among the plots. There is variation in features, such as precipitation, summer temperature, cloudiness, and the amount of fog, for which we do not have data but that could overrule the microclimatic differences due to edge effects.     

Impact of shrub canopies on understorey vegetation in western Eurasian tundra

Question: How does the composition and species richness of understorey vegetation associate with changing abundance of deciduous shrub canopies? What are the species‐specific associations between shrubs and understorey plants? Location: Tundra habitats along an over 1000‐km long range, spanning from NW Fennoscandia to the Yamal Peninsula in northwest Russia. Methods: The data from 758 vegetation sample plots from 12 sites comprised cover estimates of all plant species, including bryophytes and lichens, and canopy height of deciduous shrubs. The relationships between shrub volume and cover of plant groups and species richness of vegetation were investigated. In addition, species‐specific associations between understorey species and shrub volume were analysed. Results: Shrub abundance was shown to be associated with the composition of understorey vegetation, and the association patterns were consistent across the study sites. Increased forb cover was positively associated with shrub volume, whereas bryophyte, lichen, dwarf shrub and graminoid cover decreased in association with increasing volume of deciduous shrubs. The total species richness of vegetation declined with increasing shrub volume. Conclusions: The results suggest that an increase of shrubs – due to climatic warming or a decrease in grazing pressure – is likely to have strong effects on plant–plant interactions and lead to a decrease in the diversity of understorey vegetation.     

Limited Edge Effects Along a Burned‐Unburned Bornean Forest Boundary Seven Years after Disturbance

Large parts of the everwet tropics have been burned, leaving many unburned–burned forest edges. Here we studied a Bornean forest edge to determine: (1) how unburned and burned forest differ in vegetation structure, diversity, composition and plant functional traits 7 yr after fire, and (2) if these variables showed significant edge effects. Environmental and inventory data from 120 plots (0.01 ha each), covering both sides of a ～1.3 km forest boundary were sampled. Differences in vegetation structure, diversity, composition and plant functional traits were analyzed in relation to disturbance type (Mann–Whitney tests) and edge distance (partial correlation analysis that controlled for confounding effects of elevation, slope and fire intensity). Seven years after fire, burned forest differed significantly from unburned forest in most measured variables while few significant edge effects were detected, i.e., there existed a sharp delimitation between the two forest types. The regeneration of the burned forest depended almost entirely on in situ recruitment with little input of late successional species from the neighboring old growth forest. On the other hand, old growth forest showed few signs of edge degradation. A possible explanation for these results might be related to the absence of a mast fruiting event during these first 7 yr of forest recovery, resulting in low levels of late successional species seed input into the burned forest, combined with the quick development of a closed canopy in the burned forest by early successional species that shielded the unburned forest from adverse edge effects.     

Analysis of factors determining the biological availability of 137Cs in forest ecosystem soils

On five forest plots varying in species composition of woody plants and soil properties, 137Cs accumulation by vegetation of the forest understorey has been studied. Differences in 137Cs availability for root uptake are shown to be dependent on a vertical distribution of 137Cs content over the soil profile, percentage of exchangeable 137Cs and distribution of plant root systems (fungous mycelium) in soil. A 137Cs-bioavailability index is suggested and its non-linear relationship with 137Cs transfer factors to different plant species in the understorey is shown.     

Changes in plant species composition and litter production in response to roads and trails in the laurel forest of Tenerife (Canary Islands)

Abstract

Road density has increased in the Canary Islands' forests during the last century, affecting an unknown amount of forested area. We studied road effects on vegetation in the relict laurel forest of Tenerife. We assessed edge effects on plant species richness, plant composition and litter production. Effects of anthropogenic corridors on vegetation differed between paved roads and unpaved trails. Opportunistic species (shade intolerant) dominated road edges, but composition differed among all sites. Multivariate analysis revealed convergence in species composition along the corridor-interior gradient. For trails, both species richness and litter production did not differ significantly between edge and interior. Road edge effects on vegetation were detectable only within the first 10 m towards the interior. This suggests that the main effects of roads and trails on species richness are limited to the immediate edge of the laurel forest. Litter fall along road edges was half that of the interior. However, no significant differences were detected due to the high variability of the data. A buffer of approximately 10 m would result in the reduction of the total area of the remaining undisturbed laurel forest. Based on these results, the building of new paved roads should not be considered. Low human population inflow into the Anaga Rural Park needs to be maintained on a sustainable basis. Forest managers should take these road/trail effects into account when planning new road openings in this ecosystem.     

Understorey foraging and habitat selection by sheep in mixed Atlantic woodland

Abstract. The main objectives of this study were to investigate sheep foraging behaviour in mixed Atlantic woodland and to assess its impact on the forest understorey. We established 89 plots along four forest types: Fagus woodland, Quercus woodland, riparian gallery forest and conifer plantations. The presence of plant species in the forest understorey and their foraging damage was surveyed bimonthly from July 1996 to June 1997. In addition, we estimated the selection of woodland types by sheep through the pellet‐group count technique. The intensity of foraging by sheep was negligible for most of the plant species, however several species showed substantial damage in some woodland types. Among the species that were abundant and widespread in the entire study area, Rubus ulmifolius, graminoids and Ilex aquifolium were consumed most. Sheep selected only larch plantations, where grasses and Rubus were very abundant. This grazing behaviour reduced browsing damage of the understorey of woodland stands with higher conservation value, such as Quercus and Fagus woodlands.     

Consistent Effects of Disturbance and Forest Edges on the Invasion of a Continental Rain Forest by Alien Plants

Continental tropical forests are thought to be resistant to alien plant invasion due to a lack of disturbance, or low propagule pressure from introduced species. We assessed the importance of disturbance and edge effects by surveying areas of submontane and lowland forest of Amani Nature Reserve in the East Usambara mountains, Tanzania. These areas are in the vicinity of Amani Botanic Garden (ABG)—a propagule source for many alien plant species. We surveyed three edges in the vicinity of the ABG plantations, using plots interspersed along multiple 250 m transects. Survey plots were either in secondary or seminatural forest, representing a difference in past disturbance). Alien plant species richness and abundance declined with increasing distance from forest edges, indicating that edge effects were important. In addition, the effect of distance on richness and abundance of alien species as adults was much smaller in seminatural than secondary forest, emphasizing that invasion of seminatural forest is less likely to occur. Abundance and occurrence of individual species showed broadly similar declines with increasing distance from the forest edge, and lower abundance in seminatural compared to secondary forest. Alien species were dominant in 15 percent of plots surveyed. As 28 percent of the Amani nature reserve forest is within 250 m of an edge, the importance of disturbance and edges could make a potentially large proportion of the forest vulnerable to alien species invasion.     

How forest edge-center transitions in the herb layer interact with beech dominance versus tree diversity

Aims Forest fragmentation and the associated augmentation of forest edge zones are increasing worldwide. Forest edges are characterized by altered plant species richness and community composition. As the tree layer and its species composition has been shown to influence herb layer composition, changes in tree species composition or richness may weaken or strengthen edge effects in forest ecosystems. We studied effects of the edge–center transition, tree species composition and their potential interaction on the understory vegetation in the Hainich National Park, Germany's largest connected deciduous forest, allowing to cover large edge–center transects.Methods We established 12 transects in an area of 75 km 2 of continuous forest, 6 beech-dominated and 6 in multispecies forest stands. Each transect reached from the forest edge up to 500 m into the forest interior. Vegetation relevés were conducted in regular, logarithmic distances along each transect.Important findings Herb species richness was influenced by an interaction of edge effects and tree diversity level. With increasing distance from the forest edge, herb species richness remained constant in multispecies forest stands but rapidly decreased in beech-dominated forest stands. Further, herb richness was higher in the interior of multispecies forest stands. Percent forest specialists increased and percent generalists decreased with distance from the edge and this contrasting pattern was much more pronounced in beech-dominated transects. By using structural equation modeling, we identified litter depth mediated by tree species composition as the most important driver of herb layer plant species richness.     

Forest herbs show species-specific responses to variation in light regime on sites with contrasting soil acidity: An experiment mimicking forest conversion scenarios

Forest conversion from native deciduous forests to coniferous stands has been performed in many European regions and resulted in dramatic shifts in understorey plant community composition. However, the drivers for changes in specific understorey plant species remained unclear.Here, we experimentally determine the species-specific effects of light availability and chemical soil characteristics, on the vegetative and regenerative performance of five herbaceous forest understorey plants. Topsoil samples from both spruce and deciduous stands at four locations, with two levels of soil acidity, were collected and used in a common garden experiment. Additionally, three different light levels were applied, i.e., ‘light deciduous’, ‘dark deciduous’ (extra light reduction during summer) and ‘evergreen’ (light reduction during winter). In a second experiment we evaluated the germination of two of these species against the acidity and tree species at the site of origin of the soil samples.The light regime affected both the vegetative and regenerative performance of the understorey species: compared to light deciduous, Anemone nemorosa had a significantly lower performance under the evergreen light regime, Convallaria majalis under dark deciduous and Luzula luzuloides and Galium odoratum under both light regimes. The vegetative performance was lower in soil from acid sites for the acid-sensitive species G. odoratum and Primula elatior. Differences between the soils sampled under deciduous or spruce stands had no effect on the vegetative, or the regenerative performance of these species. By contrast, the germination of L. luzuloides and P. elatior was higher in soils sampled in deciduous stands and in neutral sites.Species-specific responses in vegetative and regenerative performance of adult plants to a changed light regime and soil acidification could be a reason for the changed vegetation composition in converted stands. Also lower germination and establishment of forest understorey species in spruce stands could influence the species distribution after conversion.     

Forest edges have high conservation value for bird communities in mosaic landscapes

A major conservation challenge in mosaic landscapes is to understand how trait‐specific responses to habitat edges affect bird communities, including potential cascading effects on bird functions providing ecosystem services to forests, such as pest control. Here, we examined how bird species richness, abundance and community composition varied from interior forest habitats and their edges into adjacent open habitats, within a multi‐regional sampling scheme. We further analyzed variations in Conservation Value Index (CVI), Community Specialization Index (CSI) and functional traits across the forest‐edge‐open habitat gradient. Bird species richness, total abundance and CVI were significantly higher at forest edges while CSI peaked at interior open habitats, i.e., furthest from forest edge. In addition, there were important variations in trait‐ and species‐specific responses to forest edges among bird communities. Positive responses to forest edges were found for several forest bird species with unfavorable conservation status. These species were in general insectivores, understorey gleaners, cavity nesters and long‐distance migrants, all traits that displayed higher abundance at forest edges than in forest interiors or adjacent open habitats. Furthermore, consistently with predictions, negative edge effects were recorded in some forest specialist birds and in most open‐habitat birds, showing increasing densities from edges to interior habitats. We thus suggest that increasing landscape‐scale habitat complexity would be beneficial to declining species living in mosaic landscapes combining small woodlands and open habitats. Edge effects between forests and adjacent open habitats may also favor bird functional guilds providing valuable ecosystem services to forests in longstanding fragmented landscapes.