Comparing Juniperus virginiana tree-ring chronologies from forest edge vs. forest interior positions in the Cedars Natural Area Preserve in Virginia, USA

Abstract Birds that prey on arthropods flushed by army ants north of the eastern Amazon were studied at Serra do Navio and Reserva Ducke (Brazil) and at Nappi Creek and Bartica (Guyana). Regular ant-followers are two medium-sized antbirds (Percnostola rufifrons and Gymnopithys rufigula) and two smaller ones (Pithys albifrons and Hylophylax poecilonota), plus five woodcreepers of differing sizes (from very large Hylexetastes perrotti through Dendrocolaptes picumnus, D. certhia, and Dendrocincla merula to medium-sized Dendrocincla fuliginosa). Four other regular ant-followers occur in the region but were not found at the study areas. Forty-five species of casual or nonprofessional ant-followers, including 16 antbirds, 5 woodcreepers, and 5 manakins, also were recorded. Percnostola rufifrons tends to be at the forest edge or in second growth. Pithys albifrons works around Gymnopithys rufigula, Hylophylax poecilonota peripheral to both, in the forest interior. The large Dendrocolaptes picumnus and medium-large Dendrocincla merula often capture prey near the ground, like antbirds. Unlike antbirds, which use vertical or horizontal slender perches, the woodcreepers use thick vertical perches. Dendrocolaptes certhia and Dendrocincla fuliginosa also tend to capture prey high over the ground-foraging antbirds. The woodcreepers tend to forage lower at midday. Hylexetastes perrotti is rare, and overlaps strongly with D. picumnus. There is fairly large overlap among the 9 professional ant-followers, and large ones chase away smaller ones. Nonprofessional birds tend to forage briefly or peripherally when or slightly after the professional species are active. They also forage above the antbirds and below or above the woodcreepers, and concentrate at forest edges or in second growth. The guild of ant-following birds in this region differs fairly widely from guilds in Panamá and at Belém, Brazil; the absence of large antbirds and the predominance of large woodcreepers north of the Amazon are the major differences.

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Dynamics and Edge Effect of an Atlantic Forest Fragment in Brazil

Floresta e Ambiente ◽

10.1590/2179-8087.064713 ◽

2016 ◽

Vol 23 (3) ◽

pp. 340-349 ◽

Cited By ~ 1

Author(s):

Poliana Gabriella Araújo Mendes ◽

Maria Amanda Menezes Silva ◽

Tassiane Novacosque Feitosa Guerra ◽

Ana Carolina Borges Lins-e-Silva ◽

Airton de Deus Cysneiros Cavalcanti ◽

...

Keyword(s):

Species Richness ◽

Atlantic Forest ◽

Edge Effect ◽

Woody Plants ◽

Response Times ◽

Forest Edge ◽

Northeastern Brazil ◽

Forest Fragment ◽

Canopy Tree ◽

Forest Interior

ABSTRACT The woody plants in an edge area formed approximately 35 years ago in an Atlantic Forest fragment in northeastern Brazil were examined, and three environments defined: edge, intermediate, and interior. Canopy tree densities and basal areas were found to be similar in all three environments, and also similar to previous published studies in the same region; species richness was greatest at the forest edge. The understory showed greater species richness in the forest interior, but greater diversity and equitability in the intermediate environment. Understory environments close to the forest edge demonstrated larger stem diameters than in the forest interior, although at lesser densities and with smaller total basal areas. Our results indicated the existence of distinct patterns in canopy and understory that most likely reflect differences in the response times of these two vegetation layers, with the understory being more sensitive to alterations in environmental structure.

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Effects of microhabitat on leaf traits in Digitalis grandiflora L. (Veronicaceae) growing at forest edge and interior

Archives of Biological Sciences ◽

10.2298/abs1402615k ◽

2014 ◽

Vol 66 (2) ◽

pp. 615-627

Author(s):

J. Kołodziejek

Keyword(s):

Soil Moisture ◽

Leaf Area ◽

Stomatal Density ◽

Leaf Traits ◽

Dry Mass ◽

Forest Edge ◽

Leaf Mass Per Area ◽

Forest Interior ◽

The Mean ◽

Shade Leaves

The morphological, anatomical and biochemical traits of the leaves of yellow foxglove (Digitalis grandiflora Mill.) from two microhabitats, forest interior (full shade under oak canopy) and forest edge (half shade near shrubs), were studied. The microhabitats differed in the mean levels of available light, but did not differ in soil moisture. The mean level of light in the forest edge microhabitat was significantly higher than in the forest interior. Multivariate ANOVA was used to test the effects of microhabitat. Comparison of the available light with soil moisture revealed that both factors significantly influenced the morphological and anatomical variables of D. grandiflora. Leaf area, mass, leaf mass per area (LMA), surface area per unit dry mass (SLA), density and thickness varied greatly between leaves exposed to different light regimes. Leaves that developed in the shade were larger and thinner and had a greater SLA than those that developed in the half shade. In contrast, at higher light irradiances, at the forest edge, leaves tended to be thicker, with higher LMA and density. Stomatal density was higher in the half-shade leaves than in the full-shade ones. LMA was correlated with leaf area and mass and to a lesser extent with thickness and density in the forest edge microsite. The considerable variations in leaf density and thickness recorded here confirm the very high variation in cell size and amounts of structural tissue within species. The leaf plasticity index (PI) was the highest for the morphological leaf traits as compared to the anatomical and biochemical ones. The nitrogen content was higher in the ?half-shade leaves? than in the ?shade leaves?. Denser leaves corresponded to lower nitrogen (N) contents. The leaves of plants from the forest edge had more potassium (K) than leaves of plants from the forest interior on an area basis but not on a dry mass basis; the reverse was true for phosphorus.

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Forest edge in the Brazilian Atlantic forest: drastic changes in tree species assemblages

Oryx ◽

10.1017/s0030605304000754 ◽

2004 ◽

Vol 38 (4) ◽

pp. 389-394 ◽

Cited By ~ 108

Author(s):

Marcondes A. Oliveira ◽

Alexandre S. Grillo ◽

Marcelo Tabarelli

Keyword(s):

Atlantic Forest ◽

Tree Species ◽

Current System ◽

Forest Edge ◽

Species Assemblages ◽

Brazilian Atlantic Forest ◽

Forest Fragment ◽

Forest Interior ◽

The Mean ◽

Threatened Tree Species

In this study we surveyed all trees ≥10 cm diameter at breast height within 20 0.1 ha plots in a 3,500 ha forest fragment, surrounded by sugar cane fields, of the Brazilian Atlantic forest to compare tree species assemblages at the forest edge (0–100 m into forest) vs forest interior (>200 m). Plots were perpendicular to the margin. The mean number of tree species was significantly higher in the forest interior (35.4 ± SD 7.1 vs 18.4 ± SD 4.4). In addition, forest edge differed from interior in the proportion of shade-tolerant, emergent, large/very large-fruited species, and large-seeded tree species. Among the 134 tree species recorded, 24% were exclusive to the forest edge and 57% to the forest interior. Our results suggest that both the current system of protected areas and archipelagos of small fragments (1) tend to retain only a subset of the original flora, (2) will converge in terms of floristic and ecological composition (biotic simplification and homogenization), and (3) will lose rare and threatened tree species.

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Edge effects on the distribution and abundance of birds in a southern Victorian forest

Wildlife Research ◽

10.1071/wr00057 ◽

2001 ◽

Vol 28 (3) ◽

pp. 239 ◽

Cited By ~ 19

Author(s):

Lainie Berry

Keyword(s):

Habitat Fragmentation ◽

Bird Species ◽

Forest Edge ◽

Bird Communities ◽

Forest Edges ◽

Forest Interior ◽

Open Country ◽

Habitat Edge ◽

Malurus Cyaneus ◽

Grey Shrike

An important consequence of habitat fragmentation for wildlife communities is the effect of an increase in the ratio of habitat edge to interior. This study compares the bird communities at forest/farmland edges and in forest interior at Bunyip State Park, Victoria. Overall, there was a significantly higher number of bird species and individuals in forest edge than in forest interior sites. The greater diversity of species at edge sites appeared to be due to an increase in forest-edge specialists, as opposed to an influx of open-country species. Four bird species: the white-throated treecreeper (Cormobates leucophaeus), the superb fairy-wren (Malurus cyaneus), the grey shrike-thrush (Colluricincla harmonica) and the grey fantail (Rhipidura fuliginosa) were significantly more abundant in edge sites. There were no species that were significantly more abundant in interior sites. Differences between the bird communities in edge and interior sites were attributed to increased foraging opportunities in the open country adjacent to forest edges.

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Predation rates of artificial nests in the edge and interior of a southern Victorian forest

Wildlife Research ◽

10.1071/wr01022 ◽

2002 ◽

Vol 29 (4) ◽

pp. 341 ◽

Cited By ~ 12

Author(s):

Lainie Berry

Keyword(s):

Small Mammals ◽

Nest Predation ◽

Forest Edge ◽

Forest Edges ◽

Artificial Nests ◽

Avian Predators ◽

Forest Interior ◽

Grey Shrike ◽

Predation Rates

Predation rates of nests at human-induced habitat edges may be greater than in forest interior due to differences in predator assemblages and predator activity. I compared the predation rates on 192 artificial nests containing plasticine eggs placed in forest edge and interior sites at Bunyip State Park, Victoria. The nest-predation rates at the forest edge sites were significantly greater (mean = 52–58%) than that at the forest interior sites (mean = 30–39%). The relative rates of predation by birds compared with mammals were significantly greater at forest edge sites (mean = 78–94%) than at forest interior sites (mean = 36–67%). Higher rates of nest predation at forest edges appeared to be due to greater densities of avian predators such as the grey shrike-thrush (Colluricincla harmonica), and/or lower abundances of small mammals. However, biases towards certain predator types may mask real, or create false, patterns in predation rates of artificial nests. A better understanding of how predators respond to artificial nests compared with natural nests is required. Until then, results of predation studies that use artificial nests should be interpreted with caution.

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Edge effect on carabid assemblages along forest-grass transects

Web Ecology ◽

10.5194/we-2-7-2001 ◽

2001 ◽

Vol 2 (1) ◽

pp. 7-13 ◽

Cited By ~ 14

Author(s):

T. Magura ◽

B. Tóthmérész ◽

T. Molnár

Keyword(s):

Edge Effect ◽

Abiotic Factors ◽

Canopy Cover ◽

Distinct Species ◽

Forest Edge ◽

Principal Coordinates Analysis ◽

Forest Interior ◽

Principal Coordinates ◽

Significant Edge ◽

Characteristic Species

Abstract. During 1997 and 1998, we have tested the edge-effect for carabids along oak-hornbeam forest-grass transects using pitfall traps in Hungary. Our hypothesis was that the diversity of carabids will be higher in the forest edge than in the forest interior. We also focused on the characteristic species of the habitats along the transects and the relationships between their distribution and the biotic and abiotic factors. Our results proved that there was a significant edge effect on the studied carabid communities: the Shannon diversity increased significantly along the transects from the forest towards the grass. The diversity of the carabids were significantly higher in the forest edge and in the grass than in the forest interior. The carabids of the forest, the forest edge and the grass are separated from each other by principal coordinates analysis and by indicator species analysis (IndVal), suggesting that each of the three habitats has a distinct species assemblages. There were 5 distinctive groups of carabids: 1) habitat generalists, 2) forest generalists, 3) species of the open area, 4) forest edge species, and 5) forest specialists. It was demonstrated by multiple regression analyses, that the relative air moisture, temperature of the ground, the cover of leaf litter, herbs, shrubs and canopy cover, abundance of the carabids’ preys are the most important factors determining the diversity and spatial pattern of carabids along the studied transects.

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Seasonality and forest edge as drivers of Tradescantia zebrina Hort. ex Bosse invasion in the Atlantic Forest

Brazilian Journal of Biology ◽

10.1590/1519-6984.238403 ◽

2022 ◽

Vol 82 ◽

Author(s):

W. A. Chiba de Castro ◽

R. C. Luz ◽

C. K. Peres

Keyword(s):

Invasive Species ◽

Atlantic Forest ◽

Invasive Plant ◽

Management Strategies ◽

Forest Edge ◽

Forest Interior ◽

Spatial And Seasonal Variation ◽

Four Seasons ◽

Disturbed Forest ◽

Basic And Applied Research

Abstract As a result of biodiversity and ecosystem service losses associated with biological invasions, there has been growing interest in basic and applied research on invasive species aiming to improve management strategies. Tradescantia zebrina is a herbaceous species increasingly reported as invasive in the understory of disturbed forest ecosystems. In this study, we assess the effect of spatial and seasonal variation on biological attributes of this species in the Atlantic Forest. To this end, we measured attributes of T. zebrina associated with plant growth and stress in the four seasons at the forest edge and in the forest interior of invaded sites in the Iguaçu National Park, Southern Brazil. The invasive plant had higher growth at the forest edge than in the forest interior and lower leaf asymmetry and herbivory in the winter than in the summer. Our findings suggest that the forest edge environment favours the growth of T. zebrina. This invasive species is highly competitive in the understory of semi-deciduous seasonal forests all over the year. Our study contributes to the management of T. zebrina by showing that the summer is the best season for controlling this species.

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High levels of anatomical and physiological leaf plasticity of Ocotea odorifera (Lauraceae) in response to different radiation intensities

Botany ◽

10.1139/cjb-2019-0128 ◽

2021 ◽

Vol 99 (1) ◽

pp. 23-32

Author(s):

Gabriele Marques Leme ◽

Flavio Nunes Ramos ◽

Fabricio José Pereira ◽

Marcelo Polo

Keyword(s):

Gas Exchange ◽

Stomatal Density ◽

Leaf Gas Exchange ◽

Net Photosynthesis ◽

Forest Edge ◽

Forest Fragments ◽

Gas Exchange Parameters ◽

Fragmented Forest ◽

Forest Interior ◽

Leaf Plasticity

We investigated morpho-physiological plasticity in the leaves of Ocotea odorifera trees growing under different environmental conditions in a fragmented forest. Microclimatic data were collected in a pasture matrix, forest edge, and forest interior in three Atlantic Forest fragments. Leaf gas exchange, as well as leaf anatomy in paradermal and transversal sections, were evaluated in individuals in these environments. Radiation intensity and temperature had higher effects in the pasture matrix compared with the forest interior and forest edge. However, internal portions of the canopy did not exhibit significant variation in radiation or temperature. External canopy leaves exhibited higher net photosynthesis in plants from the pasture matrix, but there was higher net photosynthesis for internal leaves from the shaded forest interior. Variation in net photosynthesis and other gas-exchange parameters were related to thinner shade leaves in forest interior individuals, and internal leaves with lower stomatal density. Although the pasture matrix, forest edge, and forest interior experienced differences in light and temperature, leaf position in the canopy produced microclimatic variations, which modified gas exchange and anatomy. Thus, O. odorifera shows the potential for reforestation programs because of its high leaf plasticity, which will enable it to overcome variations in light and temperature.

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Intraspecific and interspecific variation in use of forest-edge habitat by snakes

Canadian Journal of Zoology ◽

10.1139/z06-124 ◽

2006 ◽

Vol 84 (10) ◽

pp. 1440-1452 ◽

Cited By ~ 30

Author(s):

Gerardo L.F. Carfagno ◽

Patrick J. Weatherhead

Keyword(s):

Habitat Use ◽

Prey Availability ◽

Interspecific Variation ◽

Forest Edge ◽

Thermal Ecology ◽

Forest Edges ◽

Elaphe Obsoleta ◽

Edge Habitat ◽

Forest Interior ◽

Underlying Causes

Variation in use of edge habitat among populations and species of snakes should reflect underlying causes (e.g., thermal ecology, prey availability) and consequences (e.g., predation on birds' nests) of habitat selection. We compared the habitat use of ratsnakes, Elaphe obsoleta (Say in James, 1823), in Illinois and Ontario and compared habitat use by ratsnakes and racers, Coluber constrictor (L., 1758), in Illinois. Ratsnakes in Illinois used upland forest more and forest edges less than ratsnakes in Ontario. Female ratsnakes in Illinois used edges less than males, regardless of their reproductive status. Relative to ratsnakes, racers preferred forest edges and avoided forest interior. Female racers used edges more than males, especially while gravid. These results, and most of the seasonal patterns in habitat use, were broadly consistent with variation expected from differences in thermoregulatory needs, although other factors potentially influencing habitat use cannot be ruled out. Although it has been proposed that some forest fragmentation is likely to be beneficial for ratsnakes in Canada, such fragmentation may be detrimental to ratsnakes in Illinois but beneficial to racers. Thus, relative to forest-interior species, edge-nesting birds should be more vulnerable to predation by ratsnakes in Ontario, and fragmentation should increase the vulnerability of forest birds to nest predation by racers.

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