Are biotic and abiotic factors and seedling mechanical damage in forest-edge fragments always different from the interior?

2010 ◽  
Vol 58 (4) ◽  
pp. 241 ◽  
Author(s):  
Thamy Evellini Dias Marques ◽  
Luiz Alberto Beijo ◽  
Flavio Nunes Ramos
Keyword(s):  
Soil Moisture ◽  
Atlantic Forest ◽  
Abiotic Factors ◽  
Mechanical Damage ◽  
Landscape Fragmentation ◽  
Forest Edge ◽  
Canopy Openness ◽  
Forest Fragments ◽  
Forest Fragment ◽  
Eastern Brazil

The regeneration of fragments and adjacent landscape depends on, among others factors, seedling establishment, both in the interior and at the edge. This work considers differences between the edge and fragment interior in (1) environmental descriptors (canopy openness, temperature, soil moisture, bamboo and liana coverage and litterfall), (2) the total number of seedlings damaged and (3) the type of seedling damage. The present study was carried out in four Atlantic forest fragments in south-eastern Brazil. Environmental descriptors and artificial seedling damage were measured in 10 plots, 10 × 10 m each, in each forest fragment, i.e. five at the edges and five in the interior. Litterfall was the main cause of seedling damage in the present study. Bamboo and liana coverage, litterfall, soil moisture, canopy openness, minimal and maximal temperature and temperature amplitude, as well as the type and quantity of damage did not differ between the edge and the fragment interior. Temperature, however, was higher in the interior than in the edge fragments. The lack of difference between the edge and interior fragments was probably due to the reduced size of the remnants of the Atlantic forest studied, resulting from an intense internal anthropogenic impact on them and the early onset of this landscape fragmentation, which is quite old (~200 years).

Liana and bamboo cover threaten shrub populations in Atlantic forest fragments

2017 ◽  
Vol 65 (4) ◽  
pp. 375
Author(s):  
Magda Silva Carneiro ◽  
Caroline Cambraia Furtado Campos ◽  
Flavio Nunes Ramos
Keyword(s):  
Soil Moisture ◽  
Life Cycle ◽  
Atlantic Forest ◽  
Negative Relationship ◽  
Canopy Openness ◽  
Fragmented Landscape ◽  
Forest Fragments ◽  
Forest Species ◽  
Litter Depth ◽  
Set Up

Abiotic and biotic changes caused by forest fragmentation have led to the decline of many plant species. We sought to investigate how biotic (liana and bamboo cover) and abiotic (soil moisture, litter depth, and canopy openness) factors affect the total abundance and the numbers of individuals of Psychotria vellosiana Benth. at each stage of its life cycle (seedlings, juvenile I and II, adult reproductive and vegetative) in a fragmented landscape. P. vellosiana was selected because it is a forest species, important for fauna, especially ants and birds in the understory, and is highly abundant in semideciduous Atlantic forest areas. We hypothesised that fragments with less humidity, greater litter depth, greater canopy openness, and more liana and bamboo cover would contain fewer individuals at all five life cycle stages of that species. Ten 0.01 ha plots were set up in semideciduous Atlantic Forest fragments, and all individuals of P. vellosiana were tagged and measured. The study also measured canopy openness, soil moisture, litter depth, and bamboo and liana cover. Our results indicated that there was a negative relationship between liana and bamboo cover at all stages of the life cycle of P. vellosiana. This is one of the few studies that has investigated environmental effects on all stages of the life cycle of a plant population, and demonstrates that liana and bamboo cover can affect all stages of plant growth and development. Despite some restrictions, we can affirm that forest species are threatened by fragmentation processes, and that the main threat to local populations of P. vellosiana is liana and bamboo cover.

scholarly journals Small mammal glucocorticoid concentrations vary with forest fragment size, trap type, and mammal taxa in the Interior Atlantic Forest

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sarah A. Boyle ◽  
Noé U. de la Sancha ◽  
Pastor Pérez ◽  
David Kabelik
Keyword(s):  
Atlantic Forest ◽  
Small Mammals ◽  
Acute Stress ◽  
Physiological Stress ◽  
Fragment Size ◽  
Hair Shaft ◽  
Forest Fragments ◽  
Forest Fragment ◽  
Trapping Methods ◽  
Free Ranging

AbstractSpecies that live in degraded habitats often show signs of physiological stress. Glucocorticoid hormones (e.g., corticosterone and cortisol) are often assessed as a proxy of the extent of physiological stress an animal has experienced. Our goal was to quantify glucocorticoids in free-ranging small mammals in fragments of Interior Atlantic Forest. We extracted glucocorticoids from fur samples of 106 small mammals (rodent genera Akodon and Oligoryzomys, and marsupial genera Gracilinanus and Marmosa) from six forest fragments (2–1200 ha) in the Reserva Natural Tapytá, Caazapá Department, Paraguay. To our knowledge, this is the first publication of corticosterone and cortisol levels for three of the four sampled genera (Akodon, Oligoryzomys, and Marmosa) in this forest system. We discovered three notable results. First, as predicted, glucocorticoid levels were higher in individuals living withing small forest fragments. Second, animals captured live using restraint trapping methods (Sherman traps) had higher glucocorticoid levels than those animals captured using kill traps (Victor traps), suggesting that hair glucocorticoid measures can reflect acute stress levels in addition to long-term glucocorticoid incorporation. These acute levels are likely due to urinary steroids diffusing into the hair shaft. This finding raises a concern about the use of certain trapping techniques in association with fur hormone analysis. Finally, as expected, we also detected genus-specific differences in glucocorticoid levels, as well as cortisol/corticosterone ratios.

scholarly journals Dynamics and Edge Effect of an Atlantic Forest Fragment in Brazil

2016 ◽  
Vol 23 (3) ◽  
pp. 340-349 ◽  
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.

Spider assemblage structure and functional diversity patterns in clear-cut, logged, and undisturbed areas in a large Atlantic Forest remnant

2020 ◽  
Vol 50 (7) ◽  
pp. 608-614
Author(s):  
Ronei Baldissera ◽  
Suiane Oliveira de Quadros ◽  
Gabriela Galeti ◽  
Everton Nei Lopes Rodrigues ◽  
Luan M.V. Lazzarotto ◽  
...  
Keyword(s):  
Atlantic Forest ◽  
Species Conservation ◽  
Basal Area ◽  
Selective Logging ◽  
Canopy Openness ◽  
Forest Fragment ◽  
Clear Cut ◽  
Clear Cutting ◽  
Functional Richness ◽  
Forest Remnant

Habitat loss is one of the main consequences of landscape transformation by humans. Monitoring biodiversity changes in areas under different management strategies is fundamental for species conservation. Our study is the first to assess the role of forest disturbance history on spider (Araneae) biodiversity in the westernmost portion of the Atlantic Forest. We analyzed taxonomic and functional aspects of spider assemblages in understories in a large forest fragment in southwestern Brazil. Spiders were sampled in five 30 m × 5 m plots over three seasons in three areas with different management histories: clear-cutting, selective logging, or native plots. We also characterized tree basal area, tree density, and canopy openness. The clear-cut plots showed more canopy openness and low habitat heterogeneity due to the high density of one pioneer native tree species. Forest structure in selective logging and native plots was similar. Spider richness, abundance, and functional richness were affected only by the season. Species composition also differed among the areas depending on the season. The abundance of web-building species was mainly associated with clear-cut areas in winter and spring. These results highlight the importance of natural regeneration in the Atlantic Forest after disturbance for the conservation of regional spider biodiversity.

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

Oryx ◽  
2004 ◽  
Vol 38 (4) ◽  
pp. 389-394 ◽  
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.

scholarly journals Natural regeneration, composition and structure in a secondary Atlantic Forest fragment and in an abandoned Eucalyptus saligna Smith. (Myrtaceae) commercial plantation / Regeneração natural, composição e estrutura em um fragmento em sucessão secundária de Mata Atlântica e em reflorestamento comercial de Eucalyptus saligna Smith. (Myrtaceae) abandonado à regeneração

2021 ◽  
Vol 4 (2) ◽  
pp. 2571-2585
Author(s):  
Renata Picolo Scervino ◽  
Lya Carolina da Silva Mariano Pereira
Keyword(s):  
Species Richness ◽  
Atlantic Forest ◽  
Secondary Succession ◽  
Woody Vegetation ◽  
Canopy Openness ◽  
Forest Site ◽  
Forest Fragment ◽  
Eucalyptus Saligna ◽  
Litter Mass ◽  
Commercial Plantation

The litter horizon on forests ecosystems acts on the nutrient cycling and on the soil’s microclimate conditions. However,  to reforestation ecosystems the litter attributes can conduct to alterations that can diminish the seedling establishment, as well can act on the herbivory rates. In this context, this study aimed to verify the differences and relationships between woody species diversity, the herbivory index, the litter attributes, and the canopy openness among a fragment of Atlantic Forest on secondary succession and commercial plantation of Eucalyptus saligna Smith abandoned to regeneration. This study was conducted at the Klabin’s Company “Ecological Reserve”, at Telêmaco Borba – PR, Brazil. There weren’t observed differences on the species richness and abundance among the studied sites. Litter mass and thickness were higher in E. saligna environment. However, the litter attributes only presented relationship with the woody vegetation at the Atlantic Forest site, such as abundance and species richness with litter mass (r2=0.53 and r2=0.40, respectively) and abundance with litter thickness (r2=0.63). The herbivory index was greater on the forest patch. The canopy openness was superior in the E. saligna site. At this site, the herbivory index presented a positive relation with the canopy openness (r2=0.48) and a negative with abundance (r2=0.48). Abundance also presented a negative relation with the canopy openness (r2=0.58) in the E. saligna environment. The litter horizon on the E. saligna plantation doesn’t seem to offer restrictions to regeneration of the woody vegetation. However, at this site, the higher canopy openness and the herbivory pressure over the woody vegetation may lead to a lower rate of secondary succession compared to the Atlantic Forest fragment.

scholarly journals Abiotic factors drives floristic variations of fern’s metacommunity in an Atlantic Forest remnant

2018 ◽  
Vol 78 (4) ◽  
pp. 736-741 ◽  
Author(s):  
L. E. N. Costa ◽  
R. P. Farias ◽  
A. C. P. Santiago ◽  
I. A. A. Silva ◽  
I. C. L. Barros
Keyword(s):  
Soil Moisture ◽  
Atlantic Forest ◽  
Abiotic Factors ◽  
Northeastern Brazil ◽  
Air Humidity ◽  
Dissimilarity Index ◽  
Relative Air Humidity ◽  
Forest Remnant ◽  
Environmental Variations ◽  
Curtis Dissimilarity

Abstract We analyzed floristic variations in fern’s metacommunity at the local scale and their relationship with abiotic factors in an Atlantic Forest remnant of northeastern Brazil. Floristic and environmental variations were accessed on ten plots of 10 × 20 m. We performed cluster analyses, based on Bray-Curtis dissimilarity index to establish the floristic relationship. The influence of abiotic factors: luminosity, temperature, relative air humidity and relative soil moisture was evaluated from a redundancy analysis. We found 24 species belonging to 20 genera and 12 families. The fern’s flora showed high floristic heterogeneity (>75% for most of the plot’s associations). The fern’s metacommunity was structured along an abiotic gradient modulated by temperature, luminosity, and relative soil moisture.

Use of space by the marsupial Micoureus demerarae in small Atlantic Forest fragments in south-eastern Brazil

1999 ◽  
Vol 15 (3) ◽  
pp. 279-290 ◽  
Author(s):  
Alexandra Dos Santos Pires ◽  
Fernando Antonio Dos Santos Fernandez
Keyword(s):  
Home Range ◽  
Breeding Season ◽  
Atlantic Forest ◽  
Reproductive Season ◽  
Home Ranges ◽  
Forest Fragments ◽  
Population Densities ◽  
Metapopulation Structure ◽  
Eastern Brazil ◽  
Short Period

The spatial patterns presented by the marsupial Micoureus demerarae were studied through capture–mark–recapture in two small Atlantic Forest fragments (areas 7.1 and 8.8 ha). The study took place from March 1995 to August 1997. Considering all captures of each individual, males did not have larger home ranges within the fragments than did females. A negative correlation was found between home range sizes and population densities. For males, home ranges overlapped often, and were larger during the breeding season. For females, home ranges did not overlap except for a short period when there were many individuals present, and home range sizes were not significantly larger in the breeding season. Five movements between the two forest fragments were detected, across 300 m of open vegetation. All the movements were performed by males during the reproductive season. M. demerarae in the small fragments therefore displays a metapopulation structure, although possibly an atypical one where only males disperse.

scholarly journals ABUNDANCE OF TREES USED AS FOOD BY PRIMATES IN FRAGMENTS OF ATLANTIC FOREST

2018 ◽  
Vol 1 (1) ◽  
pp. 20-41
Author(s):  
Valdecir Da Silva ◽  
Vera Lúcia da Silva ◽  
Válter Da Silva ◽  
Dimítri De Araújo Costa ◽  
Francisco De Assis da Silva ◽  
...  
Keyword(s):  
Atlantic Forest ◽  
Beta Diversity ◽  
Diversity Index ◽  
Floristic Composition ◽  
Primate Species ◽  
Forest Fragments ◽  
Forest Fragment ◽  
Forest Diversity ◽  
Large Size ◽  
Historical Factors

Forest fragmentation favours the propagation of some arboreal primate species that can alter the floristic composition of a community. This process may be associated with the loss of seed dispersants. In this work we propose to identify if the presence of frugivorous primates of medium and large size (Sapajus flavius and Alouatta belzebul) can influence forest diversity and structure. Further, we ask if the size of the fragment affects the availability of resources for these primates. Three fragments were studied in the Atlantic Forest of the State of Paraíba, Brazil, located in the municipalities of Sapé, Mamanguape, Rio Tinto, and Mataraca. In each area 25 plots of 50 x 4 m were delimited, randomly distributed along trails and transects. All trees with chest-high circumferences (CAP) above 12 cm found within the plots were marked with ribbons, and numbered continuously. A total of 114 plant species were documented in the Pacatuba Forest, 79 in the Asplan Forest, and 97 in the “Guaribas” (Sema III) Biological Reserve (REBIO) Forest. According to the Chao and Jacknife estimators, the REBIO Guaribas Forest can present more species than recorded in the present investigation. Species Tapirira guianensis, Protium giganteum and Protium heptaphyllum are the most abundant in the Asplan, Pacatuba and Sema III Forests, respectively. In the REBIO Guaribas Forest, the Shannon diversity index was (H') = 3.75, the Alpha-Fisher index was = 26.57 and the Simpson index (1-D) was = 0.90. Pacatuba was the forest fragment with the highest index of diversity (H') = 375, Alpha-Fischer = 33.74 and Simpson (1-D) = 0.95. Pacatuba and REBIO Guaribas Forsts possess greater Beta diversity. The results suggest that local and historical factors possibly increase Beta diversity, contributing to the increase in resources used as food by primates. Therefore, the presence of primates of medium and large size in the Pacatuba Forest may affect the diversity of resources, contributing to the dispersion of large fruits and seeds. The presence of primates of medium and large size can thus contribute to the preservation of floristic diversity in forest fragments.

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