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1.
Acta sci., Biol. sci ; 43: e52030, 2021. map, tab
Article in English | LILACS, VETINDEX | ID: biblio-1461006

ABSTRACT

We evaluated the structure of a community of frugivorous bats using composition and abundance patterns, niche amplitude and food overlap of these animals in four Atlantic Forest fragments, each one exposed to different conservation realities. For twelve months, we captured six bat species and found the seeds of 13 species of pioneering plants in 158 fecal samples. The most abundant bat species were Artibeus planirostris (25.4%), Artibeus lituratus (24.1%) and Carollia perspicillata(23.9%). Only one fragment (Fazenda Unida), the most conserved area, exhibited a significantly different composition and abundance of species. We found low trophic niche amplitude values (<0.60), associated to high food overlaps. Our results suggest that bats can adjust their foraging strategy to deal with food availability variations. By favoring pioneering plant species, the fragmentation process noted of the studied areas creates an attractive environment for bats more tolerant to this type of disturbance. The sampled areas represent important secondary forest remnants in southern Brazil that require attention to avoid an even greater loss of bat diversity.


Subject(s)
Animals , Food Chain , Chiroptera/anatomy & histology , Chiroptera/growth & development
2.
Acta sci., Biol. sci ; 42: e48339, fev. 2020. map, tab
Article in English | LILACS, VETINDEX | ID: biblio-1460917

ABSTRACT

Human activities result in the formation of a mosaic of forest patches within a non-habitat matrix. The response of the local biodiversity to changes in land-use may occur at different scales. It is important to evaluate the effects of the attributes of both the patches and the surrounding landscape on the occupancy of forest patches by animal populations. Here, we assessed the predictive potential of local (basal area, tree density), patch (size, shape) and landscape scale (total area of forest, number of patches, matrix permeability, patch proximity) variables on the occupancy of forest patches by the syntopic primates Alouatta caraya, Sapajus libidinosus and Callithrix penicillata in the city of Goiânia in the Cerrado region of central Brazil. We used playback to survey primate populations in 22 focal patches and assessed the landscape within a 1000 m buffer zone around each site. In A. caraya, occupancy was influenced by the shape of the focal patches, the amount of forest and fragmentation level of the landscape. Focal patch size and the permeability of the matrix were the principal determinants of the occupancy of S. libidinosus. None of the predictors influenced patch occupancy in C. penicillata, and the structure of the vegetation did not influence occupancy in any of the species. The preservation of as many forest patches as possible, both large and small, as well as gallery forests, and the enhancement of matrix permeability will be essential for the long-term conservation of the syntopic primates of the Cerrado of central Brazil.


Subject(s)
Animals , Soil Permeability , Primates
3.
Biota Neotrop. (Online, Ed. ingl.) ; 19(4): e20180722, 2019. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1038868

ABSTRACT

Abstract: This study aimed to present a list of the species of frugivorous butterflies occurring in Atlantic Forests, in the Conservation Units: National Forest of Chapecó (FLONA), Ecological Station of Mata Preta (ESEC) and State Park of Araucárias (PAEAR) and adjacent forest fragments, located in the western region of the state of Santa Catarina. Three samplings were conducted between December 2017 and March 2018, totaling 24 days of collection in each sampling area. Van Someren-Rydon traps were used to capture frugivorous butterflies. There were 4,231 frugivorous butterflies belonging to four subfamilies, 12 tribes and 49 species. In all, 37 species of frugivorous butterflies were sampled in FLONA and 29 in adjacent forest fragments. In ESEC, 29 species and 33 in adjacent forest fragments. In PAEAR, 33 species and 28 in adjacent forest fragments. Of the total species registered, 15 species are new records for the state of Santa Catarina and 11 are new records for the western region of the state. The most abundant species for FLONA were: Manataria hercyna (Hübner, 1821) and Hermeuptychia sp. In ESEC, were Hermeuptychia sp. and Yphthimoides ordinaria (Freitas, Kaminski & Mielke, 2012). In PAEAR, greater abundance of Forsterinaria quantius (Godart, 1824) and Eryphanes reevesii (Doubleday, 1849) were verified. For the adjacent forest fragments to Conservation Units, there was a greater abundance of Hermeuptychia sp., Moneuptychia soter (Butler, 1877), Morpho epistrophus (Fabricius, 1796) e Forsterinaria quantius (Godart, 1824). Satyrinae presented higher richness (S = 34) and abundance (90.58%) in all areas sampled. The rarefaction and extrapolation curves for the Conservation Units and adjacent forest fragments showed a greater rise in the FLONA and PAEAR sampling units and their adjacent forest fragments. The estimated sampling coverage for Conservation Unit and forest fragments was above 97%. The richness calculated through the Jackknife 1 estimator, for the FLONA and PAEAR samplings, presented a value of 50.75 and 37.09, respectively. The fauna of frugivorous butterflies from this region, first investigated in areas of Conservation Units, showed to be expressive and well represented in the Atlantic Forest Biome, indicating its potential as a refuge for biodiversity.


Resumo: O estudo teve como objetivo elaborar uma lista das espécies de borboletas frugívoras ocorrentes em florestas da Mata Atlântica, nas Unidades de Conservação: Floresta Nacional de Chapecó (FLONA), Estação Ecológica da Mata Preta (ESEC) e Parque Estadual das Araucárias (PAEAR) e fragmentos florestais adjacentes, localizados na Região Oeste de Santa Catarina. Foram realizadas três campanhas de coletas entre dezembro de 2017 e março de 2018, totalizando 24 dias de coletas em cada área amostral. Para a captura das borboletas frugívoras, foram utilizadas armadilhas Van Someren-Rydon. Foram registradas 4231 borboletas frugívoras pertencentes a quatro subfamílias, 12 tribos e 49 espécies. Foram amostradas 37 espécies de borboletas frugívoras na FLONA e 29 nos fragmentos florestais adjacentes. Na ESEC 29 espécies e 33 nos fragmentos florestais adjacentes. No PAEAR 33 espécies e 28 nos fragmentos florestais adjacentes. Do total de espécies registradas, 15 espécies de borboletas frugívoras são novos registros para o estado de Santa Catarina e 11 são novos registros para a região oeste do estado. As espécies mais abundantes para a FLONA foram: Manataria hercyna (Hübner, 1821) e Hermeuptychia sp. Na ESEC, foram Hermeuptychia sp. e Yphthimoides ordinaria (Freitas, Kaminski & Mielke, 2012). No PAEAR verificou-se maior abundância das espécies Forsterinaria quantius (Godart, 1824) e Eryphanes reevesii (Doubleday, 1849). Para os fragmentos florestais adjacentes das Unidades de Conservação houve maior abundância das espécies: Hermeuptychia sp., Moneuptychia soter (Butler, 1877), Morpho epistrophus (Fabricius, 1796) e Forsterinaria quantius (Godart, 1824). Satyrinae apresentou maior riqueza (S=34) e abundância (90,58%) de borboletas frugívoras em todas as áreas amostradas. As curvas de rarefação e extrapolação, para as Unidades de Conservação e fragmentos florestais adjacentes mostraram uma maior ascendência nas unidades amostrais da FLONA e PAEAR e seus fragmentos florestais adjacentes. A cobertura estimada de amostragem para as borboletas frugívoras, para as Unidades de Conservação e fragmentos florestais, ficou acima de 97%. A riqueza calculada através do estimador Jackknife 1, mostrou-se superior à riqueza observada, sendo que para as amostragens na FLONA e PAEAR, o estimador apresentou um valor de 50,75 e 37,09, respectivamente. A fauna de borboletas frugívoras da região, investigada pela primeira vez em áreas de Unidades de Conservação, mostrou-se bastante expressiva e bem representada no Bioma Mata Atlântica, indicando seu potencial como refúgio da biodiversidade.

4.
Braz. j. biol ; 78(1): 18-24, Feb. 2018. tab, graf
Article in English | LILACS | ID: biblio-888841

ABSTRACT

Abstract Changes at the landscape scale associated with expansion in agricultural land use and changes in agricultural practices are common causes of alteration in patterns of abundance and composition of avian communities. Eared Dove (Zenaida auriculata - Des Murs, 1847) is among the most common species in the Neotropics, considered both as game and pest in some countries. Here we characterized the regional and seasonal patterns of Eared Doves abundance in Southwestern Brazil and examined the relationship between landscape features and these abundance patterns. We counted Eared Doves using the point count system along routes in summer and winter and recorded land use at two scales. We used linear regressions to model the effect of landscape matrix and land use at local scale with Doves abundance in two seasons. At the landscape scale, in winter, the abundance was greater in routes crossing landscapes dominated by plantations. In summer, it was lower in routes with large tracts of forests and mixed farming. While in winter, at the local scale, the Doves abundance was greater in routes with higher frequency of maize plantations, in summer higher abundances were observed in routes with higher frequency of sugar cane and soybean plantations. Agricultural settings, which include both sustained production of food in the form of grains as well as and large stretches of habitat suitable for reproduction, favor large population of Eared Doves.


Resumo Mudanças em escala de paisagem associadas à expansão das áreas destinadas à agricultura e às mudanças nas práticas agrícolas são consideradas importantes causas de alterações nos padrões de composição das comunidades de aves. A pomba-de-bando (Zenaida auriculata - Des Murs, 1847) é uma espécie comum na região Neotropical, sendo considerada tanto um recurso cinegético quanto uma peste agrícola em alguns países. Neste trabalho nós caracterizamos os padrões regionais e sazonais de distribuição populacional de pombas-de-bando em áreas agrícolas do sudoeste do Brasil e examinamos a relação entre características da paisagem e padrões de abundância de pombas. Coletamos os dados em transecções com pontos de contagem, alocados em estradas vicinais, percorridas no verão e no inverno. Utilizamos dados sobre as características da paisagem em duas escalas. Através de análises de regressões lineares modelamos o efeito da paisagem e do uso da terra na abundância de pombas nas duas estações. Na escala da paisagem, no inverno, a abundância foi maior em áreas com predomínio de agricultura. No verão a abundância foi menor em áreas com grandes extensões de florestas e agropecuária. Em relação ao uso do solo, no inverno a abundância de pombas foi maior em regiões com maior frequência de plantações de milho, enquanto no verão, a maior abundância esteve associada à maior frequência de cana-de-açúcar e soja. As paisagens agrícolas que apresentaram tanto produção de alimentos sob a forma de grãos quanto grandes extensões de habitat para a reprodução, como a cana-de-açúcar, favoreceram a ocorrência grandes populações de pombas-de-bando no sudoeste do Brasil.


Subject(s)
Animals , Columbidae , Seasons , Brazil , Ecosystem
5.
Rev. biol. trop ; 65(4): 1245-1260, Oct.-Dec. 2017. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-897620

ABSTRACT

Resumen El bosque seco tropical esta amenazado por una fuerte estacionalidad y presiones antropogénicas, lo cual puede afectar su estructura y composición. El objetivo del estudio fue estimar el impacto de dos matrices agropecuarias (arrozales y pasturas) en la composición florística y el almacenamiento de carbono en bosques riparios. Se establecieron cinco parcelas de muestreo (10 x 10 m cada una) en el interior y borde de los bosques en las dos matrices en julio 2013. Se midieron todos los individuos con un diámetro a la altura del pecho (dap) ≥ 5 cm. La biomasa arriba del suelo fue estimada con un modelo alométrico general, recomendado para estos bosques. El índice de valor de importancia (IVI), la riqueza de especies y los índices de diversidad alfa fueron estimados. Fueron realizados análisis de varianza y pruebas de comparación de medias de Fisher LSD. Se registró un total de 32 familias, 21 géneros y 45 especies (29 y 33 especies para pasturas y arrozales, respectivamente) de árboles en 0.2 ha. Las especies más abundantes y más importantes ecológicamente fueron: Oxandra espintana y Calliandra sp. (520 y 241 individuos/ha y 72 y 48 % de IVI, respectivamente). Estos bosques presentaron una dominancia media de 33.9 m2/ha sin efecto estadístico (P< 0.05) de la posición del bosque ni de la matriz. La matriz del paisaje no afectó (P> 0.05) los índices de la diversidad alfa. Los árboles más grandes y el mayor carbono fueron encontrados en la matriz de pasturas en comparación con la de arrozales (14.6 vs 13.4 cm de dap y 72.9 vs 45.6 t C/ha, respectivamente). Esta investigación provee un entendimiento de la riqueza y composición arbórea y almacenamiento de carbono de bosques ribereños en dos matrices agropecuarias, lo cual podría servir para el establecimiento de sistemas silvopastoriles con especies nativas.


Abstract The tropical dry forest is a typical lowland ecosystem that is threatened by a strong seasonality and anthropogenic pressures, which can affect the forest composition and structure. The objective of this study was to estimate the impact of two agricultural matrices on the floristic composition and carbon storage in riparian forests. For this, five permanent plots (10 x 10 m each) were established and sampled in the forest interior and at the edge of two agricultural matrices (rice fields and pasture lands), in July 2013. All individuals with a diameter at breast height (dbh) ≥ 5 cm were recorded and measured, and the aboveground biomass was estimated with a general allometric model. Additionally, the importance value index (IVI), species richness and Alpha´s diversity indexes were estimated; an analysis of variance and means comparison tests of Fisher LSD were also carried out. A total of 32 families, 21 genera and 45 species (29 and 33 species in pasture lands and rice fields, respectively) of trees in 0.2 ha were recorded. The most abundant and most ecologically important species were Oxandra espintana and Calliandra sp. (520 and 241 individuals/ha and 72 and 48 % of IVI, respectively). These forests presented a mean dominance of 33.9 m2/ha with no effect (P< 0.05) of forest location or agricultural matrix. The matrix of the landscape did not affect (P> 0.05) the Alpha diversity indexes. The biggest trees and greatest carbon storage were found in forests with pasture matrices when compared to rice fields (14.6 vs 13.4 cm of dbh and 72.9 vs 45.6 t C/ha, respectively). This research provides an understanding of the tree richness and composition and carbon storage of riparian forests in two agricultural matrices, which could be a basis for the establishment of silvopastoral systems with native species.

6.
Rev. biol. trop ; 65(2): 525-534, Apr.-Jun. 2017. tab, ilus
Article in English | LILACS-Express | LILACS | ID: biblio-897560

ABSTRACT

AbstractThe spatial and temporal distributions of vegetation can be influenced by edaphic and environmental factors as well as disturbances. The present study was undertaken to characterize the distribution and spatial dependence of species diversity in a fragment of semideciduous seasonal forest after a disturbance event by fire and to identify changes during natural regeneration. The fire, occurred in 1999, and surveys were undertaken in 2000, 2005 and 2014 in 26 geo-referenced plots (400 m²) distributed along two transects. The Fire Damage Index (FDI) in each plot was based on a scale from 0 to 5, and all of the arboreal individuals with diameters at breast height (DBH) ≥ 5 cm were identified in each plot. Species diversity was calculated using the Shannon index (H'), and species richness (S) was estimated using species accumulation curves; variations between the surveys compared based on the means and standard errors. The S, H' and FDI data were submitted to non-spatial exploratory and geostatistical analyses. After adjusting the semivariograms, the levels of spatial dependence were classified, and interpolation of the variables values were performed using ordinary kriging to characterize their spatial distributions in the form of maps. Spatial analysis was used to identify and characterize differences between the post-fire surveys in terms of the configurations of the arboreal community. The fire event influenced the spatial and temporal structures of the variables S and H'. These variables showed spatial dependence and aggregated distributions, with reduction in the distance under spatial influences and a uniformity of individuals distribution in the forest fragment at the different surveys. This research characterized the distribution and spatial dependence of the variables S and H' in a forest fragment after a fire event and the alterations in the arboreal community structure during natural regeneration.


ResumenLa distribución espacial y temporal de la vegetación esta influenciada por factores edáficos, ambientales y alteraciones. En ese contexto, el objetivo del estudio fue caracterizar el patrón de distribución y la dependencia espacial de la diversidad de especies en un fragmento de bosque estacional semideciduo, donde ocurrió un incendio, e identificar alteraciones a lo largo del proceso de regeneración natural. El incendio ocurrió en 1999, y en 2000, 2005 y 2014, se hicieron inventarios florísticos en 26 parcelas (400 m2) georreferenciadas y distribuidas en dos transectos. El índice de daño del fuego (IDF) se evaluó en cada parcela con base en una escala de 0 a 5. En cada inventario se identificaron las plantas arbóreas con diámetro a altura de pecho (DAP) ≥ 5 cm, calculando la diversidad de especies con base en el índice de Shannon (H') y estimando la riqueza de especies (S). Esas variaciones fueron analizadas utilizando la curva de acumulación de especies, y la variación entre inventarios fue comparada con base en las medias y el error estándar. Los datos de S, H' e IDF fueron sometidos a análisis exploratorio no espacial y a análisis geoestadístico. Después del ajuste de los semivariogramas, se clasificó el nivel de dependencia espacial y se hizo la interpolación de datos por Krigeado ordinario para caracterizar, en mapas, el patrón de distribución espacial de esas variables. Se encontró diferencia entre los inventarios realizados después del incendio, como en la configuración de la comunidad arbórea, por lo que el análisis espacial permitió identificar y caracterizar este hecho. El incendio afectó la estructura espacial y temporal de las variables S y H'. Estas variables presentan dependencia espacial y la distribución agregada, con distancias más pequeñas bajo influencia espacial, y la uniformidad de la distribución de los individuos en el fragmento de bosque durante las distintas etapas. Por último, se caracterizó la distribución y la dependencia espacial de las variables S e H 'en un fragmento de bosque después de un incendio, y las alteraciones en la estructura de la comunidad arbórea durante la regeneración natural.

7.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467032

ABSTRACT

Abstract Changes at the landscape scale associated with expansion in agricultural land use and changes in agricultural practices are common causes of alteration in patterns of abundance and composition of avian communities. Eared Dove (Zenaida auriculata - Des Murs, 1847) is among the most common species in the Neotropics, considered both as game and pest in some countries. Here we characterized the regional and seasonal patterns of Eared Doves abundance in Southwestern Brazil and examined the relationship between landscape features and these abundance patterns. We counted Eared Doves using the point count system along routes in summer and winter and recorded land use at two scales. We used linear regressions to model the effect of landscape matrix and land use at local scale with Doves abundance in two seasons. At the landscape scale, in winter, the abundance was greater in routes crossing landscapes dominated by plantations. In summer, it was lower in routes with large tracts of forests and mixed farming. While in winter, at the local scale, the Doves abundance was greater in routes with higher frequency of maize plantations, in summer higher abundances were observed in routes with higher frequency of sugar cane and soybean plantations. Agricultural settings, which include both sustained production of food in the form of grains as well as and large stretches of habitat suitable for reproduction, favor large population of Eared Doves.


Resumo Mudanças em escala de paisagem associadas à expansão das áreas destinadas à agricultura e às mudanças nas práticas agrícolas são consideradas importantes causas de alterações nos padrões de composição das comunidades de aves. A pomba-de-bando (Zenaida auriculata - Des Murs, 1847) é uma espécie comum na região Neotropical, sendo considerada tanto um recurso cinegético quanto uma peste agrícola em alguns países. Neste trabalho nós caracterizamos os padrões regionais e sazonais de distribuição populacional de pombas-de-bando em áreas agrícolas do sudoeste do Brasil e examinamos a relação entre características da paisagem e padrões de abundância de pombas. Coletamos os dados em transecções com pontos de contagem, alocados em estradas vicinais, percorridas no verão e no inverno. Utilizamos dados sobre as características da paisagem em duas escalas. Através de análises de regressões lineares modelamos o efeito da paisagem e do uso da terra na abundância de pombas nas duas estações. Na escala da paisagem, no inverno, a abundância foi maior em áreas com predomínio de agricultura. No verão a abundância foi menor em áreas com grandes extensões de florestas e agropecuária. Em relação ao uso do solo, no inverno a abundância de pombas foi maior em regiões com maior frequência de plantações de milho, enquanto no verão, a maior abundância esteve associada à maior frequência de cana-de-açúcar e soja. As paisagens agrícolas que apresentaram tanto produção de alimentos sob a forma de grãos quanto grandes extensões de habitat para a reprodução, como a cana-de-açúcar, favoreceram a ocorrência grandes populações de pombas-de-bando no sudoeste do Brasil.

8.
Acta sci., Biol. sci ; 38(4): 411-417, oct.-dec. 2016. ilus, tab
Article in English | LILACS | ID: biblio-831617

ABSTRACT

The goal of this study was to evaluate the population structure of Lonchocarpus cultratus located in a riparian zone in the flood plain of the upper Paraná River. Data were collected on the stem diameter at breast height (DBH) and the plant height from two phytosociological inventories, which were performed with a 14- year interval, using data collected in studies conducted in 1992 and 2006 in an Atlantic Forest riparian zone remnant of Paraná State, Brazil. Class intervals for DBH and plant height were defined using the Spiegel equation, and the measured values were distributed between the different distinct classes. The distribution of individuals between the different DBH classes was analyzed using de Liocourt's quotient (q). For both stages of the study, the DBH distribution resulted in an inverted-J curve, as expected for uneven-aged forests. The distribution of the height values was irregular, as expected for an early succession species. The de Liocourt q indicated an unbalanced distribution for both stages. However, there was a tendency towards balance in the second stage. The results imply that the studied population was maturing and maintaining its self-regenerating capacity while tending towards balance and presenting behavior characteristic of early succession species.


Com o objetivo de avaliar a estrutura populacional de Lonchocarpus cultratus em um trecho de floresta ripária localizado na planície de inundação do alto rio Paraná, analisaram-se os dados de diâmetro e altura obtidos a partir de dois inventários fitossociológicos realizados com intervalo de 14 anos, utilizando-se dados coletados em estudos desenvolvidos em 1992 e 2006 em um remanescente ripário de Mata Atlântica, no Estado do Paraná, Brasil. Os valores de diâmetro e de altura foram distribuídos em intervalos de classes definidos pela fórmula de Spiegel e o quociente "q" de Liocourt foi aplicado para a análise da distribuição de indivíduos entre as classes de diâmetro. A distribuição diamétrica, nas duas etapas do estudo, resultou em uma curva na forma de J-invertido, como esperado para florestas inequiâneas. A distribuição dos valores de altura mostrou-se irregular, característica de espécies de estágios iniciais de sucessão. O quociente "q " de Liocourt apresentou-se com uma distribuição não balanceada para ambas as etapas, porém observou-se uma tendência ao balanceamento na segunda etapa. Concluiu-se que a população analisada encontra-se em processo de amadurecimento, mantendo a capacidade autorregenerante, com tendência ao balanceamento e comportamento característico de espécies de estágios iniciais de sucessão.


Subject(s)
Forests , Growth and Development
9.
Biota Neotrop. (Online, Ed. ingl.) ; 15(2): e20140084, Apr.-June 2015. tab, graf
Article in English | LILACS | ID: biblio-951036

ABSTRACT

Forest fragmentation is a major cause of loss of species. We evaluated the local extinction of medium-large frugivorous bird species in six forest fragments of northern Paraná: the Parque Estadual Mata dos Godoy (PEMG), the largest and most preserved forest fragment in the region, and five other fragments. Fixed-width point counts and line transects were conducted along trails in the PEMG for 10 days: from September 2010 to March 2011, and from August 2011 to November 2011. Avian surveys in each of the other forest fragments were made over four days from October to December 2011. We compared data with a previous census carried out 10 years earlier. No extinction events were recorded from the PEMG. However, the relative abundance of species significantly changed during the ten years between surveys. In all the other forest fragments at least two frugivorous bird species disappeared, and in some as many as seven. Protecting the PEMG is crucial for the maintenance of frugivorous bird populations in our studied landscape.


A fragmentação florestal é uma das principais causas da perda de espécies. Avaliamos a extinção local de aves frugívoras de médio e grande porte em seis fragmentos do norte do Paraná: o Parque Estadual Mata dos Godoy (PEMG), maior e mais preservado remanescente florestal da região, e outros cinco fragmentos. Foram realizadas amostragens por pontos de escuta de distância limitada e por transecções no PEMG ao longo de 10 dias: entre setembro de 2010 e março de 2011, e entre agosto e novembro de 2011. Os outros cinco fragmentos foram amostrados ao longo de quatro dias entre outubro e dezembro de 2011. Os dados foram comparados com um levantamento prévio realizado há 10 anos. Não foram observadas extinções no PEMG. No entanto, foram observadas alterações significativas na abundância relativa das espécies em dez anos (Wilcoxon Signed-Rank). Nos outros fragmentos florestais verificou-se o desaparecimento de pelo menos duas espécies, sendo que a variação foi de duas a sete espécies. A proteção do PEMG parece ser crucial para a manutenção das populações de aves frugívoras na paisagem estudada.

10.
J. venom. anim. toxins incl. trop. dis ; 21: 6, 31/03/2015. graf, mapas, tab
Article in English | LILACS, VETINDEX | ID: biblio-954774

ABSTRACT

Background The reintroduction of sylvatic yellow fever in the state of São Paulo after about six decades was confirmed in the Northwestern region in 2000, where in 2008 there also occurred an important epizootic. The purpose of this study was to investigate the feeding habits of culicids potentially involved in the sylvatic transmission of the virus in this region.Methods Specimens were collected in 24 forested localities at ground level with hand nets and mouth aspirators. Collections were made quarterly between October 2006 and July 2008 during daylight hours. Blood-meal identification was carried out in mosquitoes of the tribes Aedini, Mansoniini and Sabethini. The biotin/avidin sandwich ELISA was employed to determine six source types: bird, bovine, equine, rat, human and monkey.Results A total of 24,879 females of the three tribes were obtained, 245 (0.98%) of which were engorged. The presence of three different blood sources per engorged female was the predominant situation, and included 35.10% of the total of samples processed. Samples with two or four different sources were represented by 25.31% and 25.71%, of the specimens, respectively, while just 9.39% had only one type and 1.22%, five different sources. Aedes scapularis, Ae. serratus(Group),Psorophora albigenu and Ps. ferox were the most abundant species and accounted for about 95% of the engorged specimens. Of the principal vector species,Haemagogus janthinomys/capricorniiwas found with bird, bovine and primate blood. These sources were predominant and alternated top ranking as the most frequent source according to the mosquito species and collection site. In general, primate blood was the most prevalent source.Conclusions The human population of the region visits this ecotone frequently, which indicates the need for the periodical assessment of vaccination coverage against yellow fever. The frequency of non-human primate blood source in mosquito species that show minor vector importance in yellow fever virus transmission deserves attention. The eclectic feeding habits and some aspects of the interactions between potential vectors and reservoirs of yellow fever may be associated with the habitat fragmentation characteristic of the region. We recommend that further studies on the capacity and vector competence be performed on secondary vectors in extra-Amazonian region.(AU)


Subject(s)
Animals , Yellow Fever , Yellow fever virus , Enzyme-Linked Immunosorbent Assay , Ecosystem , Diptera
11.
J. venom. anim. toxins incl. trop. dis ; 21: 1-10, 31/03/2015. map, tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1484617

ABSTRACT

AbstractBackground The reintroduction of sylvatic yellow fever in the state of São Paulo after about six decades was confirmed in the Northwestern region in 2000, where in 2008 there also occurred an important epizootic. The purpose of this study was to investigate the feeding habits of culicids potentially involved in the sylvatic transmission of the virus in this region.Methods Specimens were collected in 24 forested localities at ground level with hand nets and mouth aspirators. Collections were made quarterly between October 2006 and July 2008 during daylight hours. Blood-meal identification was carried out in mosquitoes of the tribes Aedini, Mansoniini and Sabethini. The biotin/avidin sandwich ELISA was employed to determine six source types: bird, bovine, equine, rat, human and monkey.Results A total of 24,879 females of the three tribes were obtained, 245 (0.98%) of which were engorged. The presence of three different blood sources per engorged female was the predominant situation, and included 35.10% of the total of samples processed. Samples with two or four different sources were represented by 25.31% and 25.71%, of the specimens, respectively, while just 9.39% had only one type and 1.22%, five different sources. Aedes scapularis, Ae. serratus(Group),Psorophora albigenu and Ps. ferox were the most abundant species and accounted for about 95% of the engorged specimens. Of the principal vector species,Haemagogus janthinomys/capricorniiwas found with bird, bovine and primate blood. These sources were predominant and alternated top ranking as the most frequent source according to the mosquito species and collection site. In general, primate blood was the most prevalent source.Conclusions The human population of the region visits this ecotone frequently, which indicates the need for the periodical assessment of vaccination coverage against yellow fever. The frequency of non-human primate blood source in mosquito species that show minor vector importance in yellow fever virus transmission deserves attention. The eclectic feeding habits and some aspects of the interactions between potential vectors and reservoirs of yellow fever may be associated with the habitat fragmentation characteristic of the region. We recommend that further studies on the capacity and vector competence be performed on secondary vectors in extra-Amazonian region.


Subject(s)
Animals , Feeding Behavior , Culicidae , Yellow Fever , Insect Vectors
12.
Biosci. j. (Online) ; 29(5): 1317-1327, sept./oct. 2013. tab, ilus
Article in Portuguese | LILACS | ID: biblio-946936

ABSTRACT

Florestas de borda têm características de estádios iniciais de sucessão. No entanto, essas florestas em estádio inicial produzem folhas de decomposição mais difícil e tem uma menor diversidade de invertebrados do solo que participam da decomposição da serrapilheira. Assim, é provável que a decomposição da camada de serrapilheira e a fauna do solo sejam influenciadas por características da borda em fragmentos recém criados. O objetivo desse estudo foi avaliar a decomposição da serrapilheira e a comunidade de invertebrados do solo em um fragmento de floresta Atlântica localizado em Pinheiral, RJ. Litter bags e armadilhas pittfall foram instaladas na borda e no interior do fragmento para avaliar a perda de massa da serrapilheira e a fauna do solo, respectivamente. A serrapilheira se decompôs de maneira mais lenta na borda, onde houve menor diversidade da fauna do solo e maior expressão de invertebrados micrófagos. Já no interior, onde houve maior diversidade da fauna do solo e maior atividade de invertebrados saprófago-predadores, a decomposição da serrapilheira mostrou tendência de ser mais rápida. Nesse sentido, a fragmentação em florestas secundárias pode retardar a dinâmica de decomposição da serrapilheira e, dessa forma, influenciar na ciclagem dos nutrientes na camada superficial do solo.


The vegetation of the forests edge shows characteristics of early succession stages. However, this initial stage forest produce leaves that are hard to decompose and have a lower diversity of the soil invertebrates that participate in litter decomposition. Thus, it is likely that the litter decomposition and soil fauna are influenced by the newly created fragments border characteristics. The aim of this study was to evaluate the litter decomposition and soil invertebrates in a Atlantic Rain Forest fragment located in Pinheiral, RJ, Brazil. Litter bags and pitfall traps were installed at the edge and in the interior of the forest to assess the loss of litter mass and the soil fauna, respectively. The litter decomposed more slowly on the edge, where the soil fauna was less diverse and with more expression of bacteria and fungi predators. On the forest interior, with greater soil fauna diversity and higher activity of decomposers and predators invertebrates, litter decomposition showed a tendency to be faster. Accordingly, the fragmentation in secondary forests may slow the dynamic of litter decomposition and, thus, alter the nutrient cycling in the upper soil layer.


Subject(s)
Biodiversity , Rainforest , Invertebrates
13.
Biota neotrop. (Online, Ed. port.) ; 13(2): 29-34, Apr-Jun/2013. tab
Article in English | LILACS | ID: lil-682377

ABSTRACT

Forest fragmentation affects the structure and dynamics of plant communities, leading to biodiversity loss in forest remnants. In this paper we show that in a bamboo (Guadua weberbaueri Pilger) dominated forest fragment in southwestern Amazonia edge effect may be confounded by bamboo effect, which also occur inside the forest. We measured growth, mortality and, recruitment rate of trees with DBH ≥ 10 cm, in a fragment of bamboo dominated open forest in southwestern Amazonia, state of Acre, Brazil, in 15 plots at the forest edge and 15 plots inside the forest fragment, 500 m away from the border. Time interval between censuses was 1.8 years. The average diameter growth rate differed significantly between edge (3.82 ± 0.10 mm a-1) and interior (2.39 ± 0.18 mm a-1); but there were no differences in annual mortality rate (edge = 3.8 ± 2.5 % a-1 CV = 65.7%; interior = 3.6 ± 2.6% a-1 CV = 72.2%) or in annual recruitment rate (edge = 7.1 ± 3.2% a-1 CV = 45%; interior = 8.9 ± 7.9% a-1 CV = 88.7%). Diameter growth rate, particularly of pioneer and fast-growing trees, is favored by the environmental conditions of the edge, where bamboo abundance is higher. However, the absence of an edge effect on mortality and recruitment could be due to the particular dynamics of bamboo patches, which could be mimicking forest edges and therefore masking possible edge effect in this fragment. We speculate that the mortality and recruitment patterns in fragmented forests of southwestern Amazonia is different from other areas in Amazonia and that bamboo is one of the key controllers of successional processes in these fragments.


A fragmentação florestal afeta a estrutura e dinâmica das comunidades vegetais, levando a perda da biodiversidade nos remanescentes florestais. Neste trabalho nós mostramos que em um fragmento florestal dominado por bambu (Guadua weberbaueri Pilger) no sudoeste da Amazônia, o efeito de borda deve ser confundido pelo efeito efeito do bambu, que também ocorre no interior da floresta. Nós medimos as taxas de incremento diamétrico, mortalidade e recrutamento de árvores com DAP (diâmetro a altura do peito) ≥ 10 cm, em um fragmento dominado por floresta aberta com bambu no sudoeste da Amazônia, estado do Acre, Brasil, em 15 parcelas na borda da floresta e 15 a 500 m da borda no interior do fragmento florestal. O intervalo de tempo entre os censos foi de 1,8 anos. A taxa anual de incremento diamétrico médio diferiu significativamente entre borda (3,82 ± 0,10 mm a-1) e interior (2,39 ± 0,18 mm a-1); mas não houve diferenças na taxa anual de mortalidade (borda = 3.8 ± 2.5% a-1 CV = 65.7%; interior = 3.6 ± 2.6% a-1 CV = 72.2%) e na taxa anual de recrutamento (borda = 7.1 ± 3.2% a-1 CV = 45%; interior = 8.9 ± 7.9% a-1 CV = 88.7%). A taxa de incremento diamétrico, especialmente de espécies arbóreas de estágios iniciais de sucessão ecológica e crescimento rápido, é favorecida pelas condições ambientais da borda, onde a abundância de bambu é maior. Porém, a ausência de efeito de borda sobre a mortalidade e recrutamento, pode ser devido a própria dinâmica das manchas de bambu, que podem estar imitando as bordas das florestas, e portanto, mascarando o efeito de borda neste fragmento. Nós especulamos que os padrões de mortalidade e recrutamento em florestas fragmentadas no Sudoeste da Amazônia são diferentes de outras partes da bacia Amazônica e que o bambu nessas florestas é um dos principais atores controlando a sucessão florestal nesses fragmentos.

14.
Arq. bras. med. vet. zootec ; 65(1): 1-5, fev. 2013. tab
Article in Portuguese | LILACS | ID: lil-667528

ABSTRACT

O presente trabalho consiste no primeiro relato de criptorquidismo em uma jaguatirica, adulta, de vida livre. Para a captura foram empregadas armadilhas com desarme de guilhotina, usando como isca vísceras de bovino. O animal foi contido quimicamente por meio de dardos anestésicos e mantido sob anestesia, utilizando a associação de cloridrato de quetamina e cloridrato de xilazina. Durante o exame andrológico, observou-se que o testículo esquerdo localizava-se subcutâneo, próximo à região inguinal, caracterizando-se criptorquidismo unilateral. Esse testículo apresentava-se flácido, com volume de 2,57mL, enquanto o testículo contralateral apresentava consistência firme e volume de 11,50mL. A área ocupada pelas espículas penianas mostrou-se compatível com a de animais reprodutores. O criptorquidismo é uma condição hereditária ligada à baixa variabilidade genética, já relatada em felinos silvestres consanguíneos. Nesse sentido, devido ao crescente isolamento populacional em fragmentos florestais, este achado torna-se preocupante, uma vez que pode ser indicativo de endogamia em populações de jaguatiricas de vida livre.


This paper is the first report of unilateral cryptorchidism in an adult wildlife ocelot, captured in Parque Estadual do Rio Doce. Cage traps were used to capture the animal, using bovine offal as bait. The animal was anesthetized with anesthetic darts and kept under anesthesia through a combination of ketamine and xylazine. The andrologycal examination showed that the left testicle was located subcutaneously near the inguinal region. In this case of unilateral cryptorchidism, the testis was soft and had a volume of 2.57mL, while the contralateral testis had a firm consistency and volume of 11.50mL. The length of the region occupied by the penile spikes was similar to other breeding animals. Cryptorchidism is an inherited condition linked to low genetic variability previously reported in consanguineous wild cats. Due to the increasing isolation of wild population in forest fragments, this finding is concerning because it can be indicative of inbreeding in wild ocelot populations.


Subject(s)
Cryptorchidism/diagnosis , Cryptorchidism/veterinary , Felidae/abnormalities , Felidae/growth & development , Anesthesia , Anesthesia/veterinary
15.
Biota neotrop. (Online, Ed. port.) ; 13(3): 332-342, 2013. tab, graf
Article in Portuguese | LILACS | ID: lil-693995

ABSTRACT

O processo de urbanização vem sendo tratado como uma das maiores ameaças à biodiversidade e, dentre os organismos encontrados em áreas urbanas, as formigas representam um grupo importante, porém ainda pouco estudado comparado a outros insetos. Conhecer a riqueza e a composição da mirmecofauna que habita áreas urbanas e os fatores que estão exercendo pressão sobre essas comunidades são imperativos para a elaboração de planos de manejo e conservação. Este estudo teve como objetivo avaliar a diversidade de formigas de dez cidades localizadas na região austral do Bioma Mata Atlântica. As assembleias foram avaliadas e comparadas por meio da análise de rarefação e estimativas de riqueza. Foram registradas 8.790 ocorrências de formigas, tendo sido identificadas 140 espécies, representantes de 37 gêneros, 19 tribos e nove subfamílias o que corresponde a 38,2% da mirmecofauna conhecida para o estado de Santa Catarina. As assembleias de formigas não diferiram marcadamente quanto à riqueza, entretanto, nove cidades apresentaram espécies exclusivas mostrando variação na composição das espécies. A existência e a conservação de ambientes como fragmentos florestais e áreas verdes no perímetro urbano podem explicar a riqueza e abundância dessas assembleias de formigas.


The urbanization process has been considered as one of the major threats to biodiversity and, among organisms found in urban areas ant represents an important but poorly studied group compared with other insects. Knowing the richness and composition of ant fauna inhabiting urban areas and factors exerting pressure on these communities are essential to set up management and conservation plans. The present study aimed to evaluate the diversity of ants in ten cities from the southern region of the Atlantic Forest biome. Assemblages were evaluated and compared by means of rarefaction and richness estimators. We recorded 8,790 occurrences, 140 species distributed into 37 genera, 19 tribes and nine subfamilies, corresponding to 38.2% of ant fauna known for the Santa Catarina State. Ant assemblages did not differ markedly as for richness, however nine cities presented exclusive species, suggesting variation in species composition. The existence and conservation of environments like forest remnants and green areas within the urban perimeter can explain the richness and abundance of these ant assemblages.

16.
Braz. j. biol ; 72(3): 587-594, Aug. 2012. ilus, tab
Article in English | LILACS | ID: lil-649349

ABSTRACT

The edge of a forest fragment can be considered a zone of transition between the interior of the fragment and the surrounding habitat matrix. Plants along the edge are more exposed to disturbance and microclimate variation than interior plants, resulting in the so-called edge effect. In this study, we compared leaf area, fluctuating asymmetry and chemical (water, nitrogen and tannins) leaf traits between Erythroxylum tortuosum plants inhabiting the edge with those growing in the interior of a cerrado fragment in Brazil. We also describe the temporal variation in the vegetative and reproductive phenological events of E. tortuosum plants throughout the season. Nitrogen, leaf area and fluctuating asymmetry did not differ between the two plant groups. Young leaves of the edge plants had significantly higher levels of tannins and lower levels of water than those of interior plants. We suggest that differences in leaf chemical concentrations between edge and interior plants may occur due to factors such as light intensity, wind, temperature and leaf age rather than plant stress. With respect to plant phenology, most reproductive events occurred during the spring. Leaf buds and young leaves prevailed during the rainy season. In the dry season, however, the vegetative events decreased due to leaf senescence followed by leaf abscission.


A borda de um fragmento florestal pode ser considerada uma zona de transição entre o interior do fragmento e a matriz de habitat. As plantas localizadas na borda estão mais expostas a distúrbios e variações microclimáticas do que as plantas do interior, resultando no chamado efeito de borda. Neste estudo, a área foliar, a assimetria flutuante e os caracteres químicos das folhas (água, nitrogênio e taninos) foram comparados entre plantas de Erythroxylum tortuosum situadas na borda e no interior de um fragmento de cerrado brasileiro. A variação temporal de eventos fenológicos vegetativos e reprodutivos de E. tortuosum também foi investigada durante o período de estudo. Nitrogênio, área foliar e assimetria flutuante não diferiram entre os dois grupos de plantas. As folhas jovens das plantas localizadas na borda apresentaram, significativamente, níveis mais altos de taninos e menores níveis de água do que as plantas do interior. Sugere-se que as diferenças nos conteúdos químicos foliares entre as plantas da borda e do interior devem ter ocorrido em razão de fatores como intensidade luminosa, vento, temperatura e idade foliar e não por causa do nível de estresse da planta. Com relação à fenologia, a maioria dos eventos reprodutivos ocorreu durante a primavera. Os botões foliares e as folhas novas prevaleceram durante a estação chuvosa. No entanto, na estação seca, os eventos vegetativos decresceram por causa da senescência das folhas, seguida pela abscisão foliar.


Subject(s)
Erythroxylaceae/chemistry , Erythroxylaceae/physiology , Nitrogen/analysis , Plant Leaves/chemistry , Trees , Tannins/analysis , Water/analysis , Brazil , Erythroxylaceae/classification , Seasons
17.
Braz. j. biol ; 72(2): 257-265, May 2012.
Article in English | LILACS | ID: lil-639434

ABSTRACT

This study aims to identify the remnant tree flora in six forest fragments in the metropolitan area of Belém and to analyze these fragments in terms of biological conservation, species richness and diversity in the local urban landscape. The fragments and their respective sampling areas were as follows: Amafrutas reserve (15 ha), Trambioca Is. reserve (2 ha), Bosque Rodrigues Alves city park (15 ha), Combu Is. reserve (10 ha), Gunma Park reserve (10 ha) and Mocambo reserve (5 ha). Inventories were built from lineal plots of 250 m² and included trees with DBH equal to or greater than 10 cm at a height of 1.3 m above ground. Sixty-nine families and 759 species, of which eight were officially listed as endangered (Brazilian National Flora: Ministry of Environment, Normative Instruction of September, 2008; Pará State Flora: Decree Nº. 802 of February 2008) were recorded. These endangered species are: Aspidosperma desmanthum Benth. ex Müll. Arg. (Apocynaceae), Cedrela odorata L. (Meliaceae), Eschweilera piresii S.A Mori (Lecythidaceae), Euxylophora paraensis Huber (Rutaceae), Hymenolobium excelsum Ducke (Leguminosae), Manilkara huberi (Ducke) Chevalier (Sapotaceae), Tabebuia impetiginosa (Mart. ex DC.) Standl. (Bignoniaceae), Mezilaurus itauba (Meisn.) Taub. ex Mez (Lauraceae) and Qualea coerulea Aubl. (Vochysiaceae). Emergency actions such as implementing management plans for already existing Conservation Units, the creation of new such units in areas of primary forest fragments (as in the case of the Amafrutas reserve), as well as the intensification of actions of surveillance and monitoring, should be undertaken by Federal, State, and Municipal environmental agencies so as to ensure the conservation of these last primary forest remnants in the metropolitan area of Belém.


O presente estudo teve o objetivo de identificar a flora arbórea remanescente em seis fragmentos florestais da região metropolitana de Belém-PA, além de analisar esses fragmentos em termos de conservação, riqueza e diversidade no cenário urbano da região. Os fragmentos, com respectivas áreas amostradas, foram: Amafrutas (15 ha), Ilha Trambioca (2 ha), Bosque Rodrigues Alves (15 ha), Ilha do Combu (10 ha), Gunma (10 ha) e Mocambo (5 ha). Os inventários foram realizados utilizando-se parcelas lineares de 250 m², com inclusão de árvores com diâmetro a 1,3 m do solo (DAP) igual ou acima de 10 cm. Foram registradas 69 famílias e 759 espécies, sendo que oito destas estão em listas oficiais de espécies ameaçadas de extinção (Flora Nacional: Instrução Normativa do MMA de setembro de 2008; Flora do Pará: Decreto 802, de fevereiro de 2008). As espécies ameaçadas são: Aspidosperma desmanthum Benth. ex Müll. Arg. (Apocynaceae), Cedrela odorata L. (Meliaceae), Eschweilera piresii S.A Mori (Lecythidaceae), Euxylophora paraensis Huber (Rutaceae), Hymenolobium excelsum Ducke (Leguminosae), Manilkara huberi (Ducke) Chevalier (Sapotaceae), Tabebuia impetiginosa (Mart. ex DC.) Standl. (Bignoniaceae), Mezilaurus itauba (Meisn.) Taub. ex Mez (Lauraceae) e Qualea coerulea Aubl. (Vochysiaceae). Ações emergenciais, como a implementação dos planos de manejo das Unidades de Conservação (UCs) já existentes, a criação de novas UCs em áreas de fragmentos de florestas primárias (como é o caso da área da Amafrutas), bem como o fortalecimento dos serviços de vigilância e fiscalização, devem ser tomadas pelos órgãos ambientais (municipal, estadual e federal), de forma a assegurar a conservação desses últimos remanescentes de florestas primárias da região metropolitana de Belém-PA.


Subject(s)
Biodiversity , Conservation of Natural Resources , Environmental Monitoring , Trees/classification , Brazil
18.
Acta sci., Biol. sci ; 33(2): 197-207, Apr. - Jun. 2011. ilus, tab
Article in English | LILACS | ID: biblio-875446

ABSTRACT

This study examined the structure and species richness of the avifauna in CEDETEG campus of Universidade Estadual do Centro-Oeste (Unicentro), in the urban area of Guarapuava, at Paraná State. Data were monthly taken from July 2006 to June 2007 using transects. A total of 125 bird species belonging to 42 families and 16 orders was recorded. The absence of large frugivorous species reveals the destabilization of native vegetation, evidencing that the current floristic structure does not support more specialized species. However, from the total amount of registered birds, 47 (38%) are related to the forest environment in the study area and 25 species (20%) are exclusive of this environment, pointing out the strong relevance of this campus for the conservation of these populations.


Este trabalho objetivou analisar a estrutura e a riqueza da avifauna no campus CEDETEG da Universidade Estadual do Centro-Oeste (Unicentro), localizado no perímetro urbano do município de Guarapuava, Estado do Paraná. Os dados foram coletados mensalmente, entre julho de 2006 e junho de 2007, utilizando o método de transecção. Foi registrado um total de 125 espécies de aves, distribuídas em 42 famílias e 16 ordens. A ausência de grandes frugívoros acusa a desestruturação da vegetação nativa, demonstrando que a atual estrutura florística não comporta aves mais especializadas. Entretanto, do total de aves registradas, 47 (38%) estão relacionadas ao ambiente florestal, que ocorre na área de estudo, e 25 espécies (20%) do total são exclusivas deste ambiente, demonstrando a relevância do campus para a conservação destas populações.


Subject(s)
Birds , Forests , Urban Area , Fauna
19.
Braz. arch. biol. technol ; 53(6): 1371-1381, Nov.-Dec. 2010. graf, mapas, tab
Article in English | LILACS | ID: lil-572275

ABSTRACT

This study compared niche breath, prey size, and diet variability in two pairs of sympatric species of terrestrial insectivorous birds, each pair containing one species that can persist in small forest fragments and one that does not. The pairs were Myrmeciza ferruginea and Sclerurus rufigularis; and Formicarius colma and F. analis, respectively. The prey availability in forest fragments was also sampled and compared to the availability in continuous forests. Niche breath indices did not differ between pair members, but diet variability differed in the opposite direction from that hypothesized. Although the two bird species most vulnerable to fragmentation fed on larger prey than less vulnerable species, prey availability, including that based on prey size did not differ among fragmented versus continuous forest sites. Thus, diet per se appeared not to be an important cause of extinction-proneness in these species. The simplest explanation proposed, that vulnerability to fragmentation was directly related to territory size, requires testing. However, it was consistent with observations that the bird species feeding on larger prey also need larger territories.


Dieta e disponibilidade de presas de aves insetívoras terrestres em fragmentos florestais amazônicos. As aves insetívoras terrestres são um dos grupos mais vulneráveis à fragmentação de florestas tropicais; no entanto algumas espécies desta guilda ainda sobrevivem em fragmentos florestais e em florestas secundárias. Se a sensibilidade destas aves à fragmentação de florestas estivesse associada à dieta, então espécies com a dieta relativamente flexível teriam maior propensão em persistir nos fragmentos florestais. Este estudo comparou sobreposição trófica, amplitude de nicho, tamanho de presas e variabilidade de dieta de dois pares de espécies de aves insetívoras terrestres, onde cada par foi composto por uma espécie que persiste nos fragmentos e outra que não: Myrmeciza ferruginea e Sclerurus rufigularis; Formicarius colma e Formicarius analis, respectivamente. A disponibilidade de presas foi também amostrada e comparada entre os fragmentos florestais e a floresta contínua. Os índices de amplitude de nicho não foram significativamente diferentes entre membros dos pares, e a variabilidade de dieta diferiu no sentido oposto aquele previsto. Embora as espécies mais vulneráveis tenham consumido presas maiores que as espécies mais resistentes, a disponibilidade de presas não diferiu significativamente entre os fragmentos e a floresta contínua. Assim, pode ser concluído que dieta não é o principal determinante na extinção destas espécies nos pequenos fragmentos florestais. A mais simples explicação proposta, de que vulnerabilidade à fragmentação é diretamente relacionada ao tamanho do território, requer testes. No entanto, a probabilidade de que estas aves precisem de territórios maiores por que predam invertebrados maiores é consistente com observações não publicadas feitas nas áreas de estudo.

20.
Neotrop. entomol ; 39(6): 898-905, nov.-dic. 2010. ilus, tab
Article in Portuguese | LILACS | ID: lil-572468

ABSTRACT

The objective of this study was to determine the effects of forest fragmentation on ant richness in a landscape of Atlantic Forest in Northeast Brazil. More specifically, the ant richness was related to the attributes of fragments (area and distance from the fragment central point to the edge), landscape (forest cover surrounding the fragments), and tree community (plant density, richness, and percentage of shade tolerant species). The surveys were carried out in 19 fragments located in Alagoas State from October 2007 to March 2008. Samples were collected through a 300 m transect established in the center of each fragment, where 30 1-m² leaf litter samples were collected at 10 m intervals. A total of 146 ant species was collected, which belonged to 42 genera, 24 tribes and nine subfamilies. The attributes of fragments and landscape did not influence ant richness. On the other hand, tree density explained ca. 23 percent of ant richness. In relation to functional groups, both density and richness of trees explained the richness of general myrmicines (the whole model explained ca. 42 percent of the variation in this group) and percentage of shade tolerant trees explained the richness of specialist predator ants (30 percent for the whole model). These results indicate that ant fauna is more influenced by vegetation integrity than by fragment size, distance to edge or forest cover surrounding fragments.


Subject(s)
Animals , Ecosystem , Trees , Ants , Brazil , Population Dynamics
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