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.

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).

scholarly journals Population parameters of the endangered titi monkey, Callicebus coimbrai Kobayashi and Langguth, 1999, in the fragmented landscape of southern Sergipe, Brazil

2011 ◽  
Vol 71 (3) ◽  
pp. 569-575 ◽  
Author(s):  
RRD. Chagas ◽  
SF. Ferrari
Keyword(s):  
Atlantic Forest ◽  
Considerable Proportion ◽  
Reliable Estimate ◽  
Line Transect ◽  
Fragmented Landscape ◽  
Forest Fragments ◽  
Population Parameters ◽  
Data Set ◽  
In The Wild ◽  
A Site

The recently-discovered titi, Callicebus coimbrai, is endemic to the coastal Brazilian Atlantic Forest south of the São Francisco River, a region with a long tradition of deforestation. While a number of C. coimbrai populations have now been identified, little is known about basic population parameters. Considering the importance of this information for conservation planning, the population of a site in southern Sergipe (with a total area of forest of approximately 500 ha) was surveyed between April and October 2008. Standard line transect procedures were used in the four largest fragments, and additional monitoring included the use of playback broadcasts for the observation of titi groups. The presence of titis was confirmed in all the forest fragments at the site, including one of only five hectares. Two other primates - Callithrix jacchus and Cebus xanthosternos - were also recorded at the site, but were less abundant than titis. A total transect walk of 476 km provided 164 sightings of primates, the majority of which (104) were of Callicebus coimbrai. Titi groups ranged in size between two and five individuals. The most reliable estimate of overall population density, derived from the combined data set, was 12.6 individuals per km²;, although density was much higher in smaller (more disturbed) fragments. The total population of Callicebus coimbrai at the site was estimated to be at least 50 individuals, which may represent a considerable proportion of the population of the species remaining in the wild. In addition to its apparent tolerance of habitat fragmentation, densities of C. coimbrai recorded at the site compare favourably with those of other Atlantic Forest titi species.

scholarly journals Seed-dispersal networks in tropical forest fragments: area effects, remnant species, and interaction diversity

2019 ◽  
Author(s):  
Carine Emer ◽  
Pedro Jordano ◽  
Marco A. Pizo ◽  
Milton C. Ribeiro ◽  
Fernanda R. da Silva ◽  
...  
Keyword(s):  
Seed Dispersal ◽  
Negative Relationship ◽  
Species Interaction ◽  
Fragmented Landscape ◽  
Forest Fragments ◽  
Ecological Processes ◽  
Plant Seed ◽  
Generalist Species ◽  
Network Area ◽  
Functional Homogenization

ABSTRACTSeed dispersal interactions involve key ecological processes in tropical forests that help to maintain ecosystem functioning. Yet this functionality may be threatened by increasing habitat loss, defaunation and fragmentation. However, generalist species, and their interactions, can benefit from the habitat change caused by human disturbance while more specialized interactions mostly disappear. Therefore changes in the structure of the local, within fragment, networks can be expected. Here we investigated how the structure of seed-dispersal networks changes along a gradient of increasing habitat fragmentation. We analysed 16 bird seed-dispersal assemblages from forest fragments of a biodiversity-rich ecosystem. We found significant species-, interaction- and network-area relationships, yet the later was determined by the number of species remaining in each community. The number of frugivorous bird and plant species, their interactions, and the number of links per species decreases as area is lost in the fragmented landscape. In contrast, network nestedness has a negative relationship with fragment area, suggesting an increasing generalization of the network structure in the gradient of fragmentation. Network specialization was not significantly affected by area, indicating that some network properties may be invariant to disturbance. Still, the local extinction of partner species, paralleled by a loss of interactions and specialist-specialist bird-plant seed dispersal associations suggests the functional homogenization of the system as area is lost. Our study provides empirical evidence for network-area relationships driven by the presence/absence of remnant species and the interactions they perform.RESUMOInterações de dispersão de sementes formam um processo ecológico chave em florestas tropicais onde colaboram na manutenção do funcionamento do ecossistema. Porém, esta funcionalidade pode estar ameaçada pelo aumento na perda e fragmentação do habitat. Enquanto espécies generalistas e suas interações podem se beneficiar da mudança de habitat causada por distúrbios antrópicos, interações envolvendo espécies mais especialistas são, na maioria, eliminadas. Desta forma, mudanças nas redes locais, dentro de fragmentos florestais, são esperadas. Neste trabalho nós investigamos como a estrutura de redes de dispersão de sementes mudam em um gradiente de fragmentação do habitat. Nós analisamos 16 comunidades de dispersão de sementes espacialmente explícitas e distribuídas em fragmentos florestais de um ecossistema rico em biodiversidade. Nós encontramos relações significativas entre a área do fragmento e espécies, interações e estrutura das redes, sendo que o último foi determinado pelo número de espécies remanescentes em cada comunidade. O número de espécies de aves frugívoras e plantas e as interações entre eles, bem como o número de links por espécie diminuíram significativamente conforme a área dos fragmentos é perdida. Por outro lado, o aninhamento da rede mostrou uma relação negativa com a área do fragmento, sugerindo um aumento da generalização da estrutura das redes com a fragmentação do habitat. No entanto, o grau de especialização das redes não foi afetado pela área, indicando que algumas propriedades de rede podem ser resistentes à perturbação. Sendo assim, a extinção local de espécies parceiras, conjuntamente com a perda das interações e associações planta-dispersor mais especializadas, sugere uma homogeneização do sistema conforme a área do fragmento é perdida. Nosso estudo fornece evidências empíricas para as relações rede-área, sendo estas direcionadas pela presença e/ou ausência das espécies remanescentes bem como das interações que estas realizam.

scholarly journals Myxobiota of the Brazilian Atlantic Forest: species on oil palm tree (Elaeis guineensis, Arecaceae)

Rodriguésia ◽  
2010 ◽  
Vol 61 (4) ◽  
pp. 575-583 ◽  
Author(s):  
Clebson Firmino da Silva ◽  
Laise de Holanda Cavalcanti
Keyword(s):  
Atlantic Forest ◽  
Oil Palm ◽  
Elaeis Guineensis ◽  
Species Abundance ◽  
Palm Tree ◽  
Forest Fragments ◽  
Brazilian Atlantic Forest ◽  
Forest Species ◽  
Palm Trees ◽  
Ecological Reserve

Abstract Elaeis guineensis Jacq. (Arecaceae), the oil palm tree, serves as a phorophyte for many different groups of organisms, someof whichhelp decompose organic matter comingfromthe organs of the tree itself or fromremainsof other plants retained in leaf sheaths. To study the myxobiota of E. guineensis, we examined living and dead trunks, leaves, bracts and inflorescences in the Gurjaú Ecological Reserve, in the township of Cabo de Santo Agostinho, Pernambuco, Brazil. Incidence and species abundance were determined in three Atlantic forest fragments. The reported species are listed herein, followed the known distribution of each species in Brazil, and which of them occur on palm trees. All of the subclasses and five orders were recorded and 22 species were added to the list of myxomycetes associated with oil palm trees in Brazil. The highest incidence value was recorded on dead leaves. Ceratiomyxa fruticulosa (O. F. Müll.) T. Macbr., Arcyria cinerea (Bull.)Pers. and Physarum compressum Alb.& Schwein. werethe most commonspecies, while Hemitrichia serpula (Scop.) Rostaf. ex Lister showed the highest levels of abundance and incidence, thus confirming its preference for the substrates provided by palm trees.

scholarly journals Species richness and relative abundance of birds in natural and anthropogenic fragments of Brazilian Atlantic forest

2004 ◽  
Vol 76 (2) ◽  
pp. 429-434 ◽  
Author(s):  
Luiz dos Anjos
Keyword(s):  
Species Richness ◽  
Atlantic Forest ◽  
Relative Abundance ◽  
Feeding Habits ◽  
Species Number ◽  
Fragmented Landscape ◽  
Forest Fragments ◽  
Forest Fragment ◽  
Forest Patches ◽  
Forest Remnants

Bird communities were studied in two types of fragmented habitat of Atlantic forest in the State of Paraná, southern Brazil; one consisted of forest fragments that were created as a result of human activities (forest remnants), the other consisted of a set of naturally occurring forest fragments (forest patches). Using quantitative data obtained by the point counts method in 3 forest patches and 3 forest remnants during one year, species richness and relative abundance were compared in those habitats, considering species groups according to their general feeding habits. Insectivores, omnivores, and frugivores presented similar general tendencies in both habitats (decrease of species number with decreasing size and increasing isolation of forest fragment). However, these tendencies were different, when considering the relative abundance data: the trunk insectivores presented the highest value in the smallest patch while the lowest relative abundance was in the smallest remnant. In the naturally fragmented landscape, time permitted that the loss of some species of trunk insectivores be compensated for the increase in abundance of other species. In contrast, the remnants essentially represented newly formed islands that are not yet at equilibrium and where future species losses would make them similar to the patches.

scholarly journals Small mammals in high fragmented landscape in Cerrado/Atlantic Forest ecotone, Southeastern Brazil

2021 ◽  
Vol 111 ◽  
Author(s):  
Felipe S. Machado ◽  
Aloysio S. Moura ◽  
Ravi F. Mariano ◽  
Rubens Manoel dos Santos ◽  
Paulo O. Garcia ◽  
...  
Keyword(s):  
Atlantic Forest ◽  
Small Mammals ◽  
Species Turnover ◽  
Landscape Fragmentation ◽  
Southeastern Brazil ◽  
Fragmented Landscape ◽  
Forest Fragments ◽  
Ecological Groups ◽  
Environmental Filters ◽  
Generalist Species

ABSTRACT Exploratory human activities have resulted in small fragments inserted into a matrix which is inhospitable to small non-flying mammals. The effects of landscape changes alter the distribution patterns of species. Landscape fragmentation patterns for small mammals are controversial, especially considering small fragments and ecotonal regions. Based on these arguments, we investigated the diversity patterns of small mammals in small fragments in the ecotonal Cerrado/Atlantic Forest region. A total of 24 fragments (<40 ha) were studied using tomahawk, sherman and pitfall traps. We found low species richness (11 species, six marsupials and five rodents), which was not expected because it is an ecotonal region. It was verified that composition and community structure are simplified by the marked presence of generalist species and with the increase of species turnover. The small forest fragments present a microhabitat structure with lianas and streams as main environmental filters of groups with ecological similarities. Our findings suggest that these fragments must be managed in order to conserve the local biodiversity and maintain the needed characteristics to enable the occurrence of different ecological groups.

scholarly journals Position in the distributional range and sensitivity to forest fragmentation in birds: a case history from the Atlantic forest, Brazil

2009 ◽  
Vol 20 (4) ◽  
pp. 392-399 ◽  
Author(s):  
LUIZ DOS ANJOS ◽  
ROBERT D. HOLT ◽  
SCOTT ROBINSON
Keyword(s):  
Forest Fragmentation ◽  
Atlantic Forest ◽  
Endemic Species ◽  
Bird Species ◽  
Fragmented Landscape ◽  
Forest Fragments ◽  
Geographic Ranges ◽  
Endemic Birds ◽  
Highly Sensitive ◽  
Small Forest

SummaryWe tested the hypothesis that endemic bird species of the Brazilian Atlantic forest are more sensitive to forest fragmentation than non-endemics in a fragmented landscape in northern Paraná state of southern Brazil. Levels of sensitivity (high, medium, and low) were previously determined in the landscape based on the occurrences of bird species in 14 forest fragments. We evaluated 112 forest bird species and found that endemic species were more sensitive than non-endemics. Among the endemic species, highly sensitive species tended to have smaller geographic ranges. In a second analysis, we determined that birds at the edges of their geographic ranges in northern Paraná were more vulnerable to forest fragmentation. Combining both factors we found that endemic birds at the edge of their ranges were the most sensitive to fragmentation. Our results suggest that endemics and species at the edges of larger ranges might need larger tracts to ensure their continued existence within that region. Our results, however, also indicate that even small forest fragments may have considerable value for non-endemics and for species closer to the centres of their ranges.

Work Stress and Organisational Citizenship Behaviours (OCBs) in Call Centers Employees

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Sunita ◽  
Urvashi Singh ◽  
Shalini Singh ◽  
Rajnee Sharma
Keyword(s):  
Negative Impact ◽  
Call Centers ◽  
Negative Relationship ◽  
Married Couples ◽  
Call Centre ◽  
Simple Correlation ◽  
Nuclear Families ◽  
Set Up ◽  
Stress At Work ◽  
The Relationship

The present study was conducted to examine the relationship between organisational stress and organisational citizenship behaviours (OCBs) in employees of call centers. The study also further explored as how stress at work set-up has negative impact on OCBs. A sample of 250 employees working in call centre of Gurgaon belonging to an age group of 25-30 years were selected on availability basis. All were working married couples living in nuclear families. Job stress survey (Spielberger & Vagg, 1999) and Organisational Citizenship Behaviour (Bateman & Organ, 1983) were administered. Data was analysed by using simple correlation and multiple regression. Results showed the negative relationship between organisational stress and OCBs. Results of regression analysis also exhibited the negative impact of stress on OCBs. The implications for the employees are discussed.

scholarly journals Sustainable Ventilation Strategies for a Medium-Sized Space with Regional Effect

2021 ◽  
Vol 13 (9) ◽  
pp. 4651
Author(s):  
Ming-Lun Alan Fong
Keyword(s):  
Life Cycle ◽  
Life Cycle Cost ◽  
Co2 Emission ◽  
High Efficiency ◽  
Regional Climate ◽  
Cost Effective ◽  
Regional Effect ◽  
Climate Conditions ◽  
Ventilation Strategies ◽  
Set Up

The analysis of ventilation strategies is fundamentally affected by regional climate conditions and local cost databases, in terms of energy consumption, CO2 emission and cost-effective analysis. A systematic approach is covered in this paper to estimate a local economic and environmental impact on a medium-sized space located in two regions during supply-and-installation and operation phases. Three ventilation strategies, including mixing ventilation (MV), displacement ventilation (DV) and stratum ventilation (SV) were applied to medium-sized air-conditioned space with this approach. The trend of the results for three ventilation systems in the life cycle assessment (LCA) and life cycle cost (LCC) analysis is SV < DV < MV. The result of CO2 emission and regional LCC shows that SV is the lowest one in both regional studies. In comparison with the Hong Kong Special Administrative Region (HKSAR) during 20 Service years, the case analysis demonstrates that the percentage differences in LCC analysis of MV, DV & SV in Guangdong are less than 20.5%, 19.4% and 18.82% respectively. Their CO2 emission of MV, DV and SV in Guangdong are more than HKSAR in 10.69%, 11.22% and 12.05%, respectively. The present study could provide information about regional effects in the LCA and LCC analysis of three ventilation strategies emissions, and thereby help set up models for decision-making on high efficiency and cost-effective ventilation strategy plans.

Bird Extinctions in Atlantic Forest Fragments of the Viçosa Region, Southeastern Brazil

2003 ◽  
Vol 17 (6) ◽  
pp. 1827-1839 ◽  
Author(s):  
RÔMULO RIBON ◽  
JOSÉ EDUARDO SIMON ◽  
GERALDO THEODORO DE MATTOS
Keyword(s):  
Atlantic Forest ◽  
Southeastern Brazil ◽  
Forest Fragments
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