Montane Atlantic Forest Research Articles

Variabilidade morfológica foliar de Miconia sellowiana (DC.) Naudin (Melastomataceae) em diferentes fitofisionomias no Estado do Paraná

This study investigated the leaf morphology of Miconia sellowiana, in four different vegetation types: Grassland (EGL), Montane Atlantic Forest (FODM), Upper Montane Atlantic Forest (FODAM), and Araucaria Forest (FOM), at the state of Parana, Brazil. Twenty leaves were selected from six individuals from each vegetation type. Several leaf parameters were analyzed including leaf area, leaf dry mass, specific leaf area (SLA), trichomes and stomata densities, and anatomical measurements. The leaves of M. sellowiana from EGL and FODAM presented pronounced xeric characteristics, with higher mean values for stomata density, trichome density on the adaxial surface, thickness of the cuticle of adaxial epidermis, spongy parenchyma, and total lamina thickness; and lower mean values for leaf area, dry leaf mass, and specific leaf area. The use of ANOVA and PCA detected a mesophylly-to-xeromorphy gradient among the four vegetation types: FOM>FODM>EGL>FODAM. The differences are apparently associated to several environmental conditions, mainly soil characteristics and light intensity.

Diet and Abundance of the Bat Sturnira lilium (Chiroptera) in a Brazilian Montane Atlantic Forest

We studied variations in diet and abundance of the bat Sturnira lilium (Chiroptera: Phyllostomidae) in a montane Atlantic Forest, in order to investigate if patterns in this habitat differ from those in the better-studied lowlands. The diet of S. lilium was assessed based on fecal samples, whereas possible variations in abundance were documented based on capture success. We also monitored and linked variability in air temperature to fruit production of Solanaceae, the main food of S. lilium. Bats fed exclusively on fruits, mostly on Solanaceae and occasionally on Piperaceae and Cecropiaceae. S. lilium was mostly absent in the area during the colder months, suggesting that they might migrate to lower and hence warmer elevations. Absence of the bats was not related to a distinct decline in availability of fruit of Solanaceae because fruit production was not related to temperature. We conclude that in tropical montane systems, abundance of some frugivorous bats might be affected more by air temperature than by food availability. Furthermore, we reinforce the idea that preserving elevational gradients is a crucial aspect for the conservation of migratory species.

Semelparity and Factors Affecting the Reproductive Activity of the Brazilian Slender Opossum (Marmosops paulensis) in Southeastern Brazil

Data on the reproductive patterns of the Brazilian slender opossum (Marmosops paulensis) were collected in an area of Montane Atlantic forest, southeastern Brazil, from August 2002 to July 2004. Reproduction occurred from September to March in both years, a period of high food supply, probably as a way to maximize survival of juveniles. There was nearly zero postmating survival, thus, no individual took part in more than 1 breeding event. This pattern characterizes a semelparous life history, which has been described in other small didelphids and dasyurids. Females were reproductively active during months with longer day lengths and abundant fruit supply. Breeding seems to be initiated by a 12L:12D photoperiod and a rapid rate of change in day length, as demonstrated in semelparous dasyurids. Hence, the effect of photoperiodic cues on the onset of reproduction also may stand for other semelparous didelphids. We suggest that fruit availability controlled the length of breeding activity in M. paulensis, and it could play a role in the occurrence of semelparity in this species. However, semelparity may occur only due to phylogenetic constraints, whereas food supply works as a selective force maintaining this trait.

Two new species of Drosophila belonging to the canalinea group (Diptera, rosophilidae)

Drosophila piratininga sp. nov. and Drosophila sampa sp. nov., belonging to the canalinea group of the subgenus Drosophila, are described based mostly on wild-caught specimens collected at a forest reserve of the Cidade Universitária "Armando de Salles Oliveira", an urban remnant of the montane Atlantic Forest located at west São Paulo city, state of São Paulo, Brazil. The two species are readily distinguished from each other mostly by having different wing patterns: the main crossveins being remarkably clouded in the first one and unclouded in the latter. Illustrations of terminalia are also provided.

A new Neotropical species of spot-thoraxed Drosophila (Diptera, Drosophilidae)

Drosophila pauliceia sp. nov., a spot-thoraxed species closely related to Drosophila boraceia Vilela & Val, 2004, is described from flies collected in an urban remnant of the montane Atlantic Forest located at the Cidade Universitária "Armando de Salles Oliveira", São Paulo city, state of São Paulo, Brazil. The two forest-dwelling species can be externally distinguished mainly by having a different pattern of thoracic spots. A new group of spotted flies (peruensis group) is proposed to include them, in addition to Drosophila peruensis Wheeler, 1959, from Urubamba River, Peru, and Drosophila atalaia Vilela & Sene, 1982, from Brazil and Argentina. To facilitate comparisons, illustrations of the male and female terminalia of the new species and of some unpublished views of those of D. atalaia are included. Additionally, a new group of unspotted species (named caponei group) is proposed to include Drosophila caponei Pavan & Cunha, 1947 and D. neochracea Wheeler, 1959, both previously considered to be related to D. atalaia.

Seasonal Variation in the Diet of the Brazilian Slender Opossum (Marmosops paulensis) in a Montane Atlantic Forest Area, Southeastern Brazil

The diet of the Brazilian slender opossum (Marmosops paulensis) was determined through analysis of fecal samples collected in an area of montane Atlantic forest in southeastern Brazil. M. paulensis consumed insects, arachnids, gastropods, fruits, flower parts, and small vertebrates. The observed preference for Piper fruits could be related to the spatiotemporal predictability of this item, whereas the observed preference for the Coleoptera, the Blattodea, and the Opiliones could be due to overestimation of hard-bodied prey. Diet composition varied seasonally, with invertebrates and flower parts being consumed more during the dry season, probably because of their higher relative abundance when compared to fruits in this season. Diet was more diverse during the dry season, because of the inclusion of new fruit species and the reduced contribution of Piper fruits in the diet. We suggest that M. paulensis is more frugivorous than previously thought and that this species can be an important seed disperser of pioneer plants, especially of Piper species.

Environmental heterogeneity and disturbance by humans control much of the tree species diversity of Atlantic montane forest fragments in SE Brazil

The effects of human impact and environmental heterogeneity on the tree species diversity were assessed in 20 fragments of tropical montane seasonal forest in southeastern Brazil. Previous surveys of the tree community, soils and topography of the fragments provided the bulk of the data. The diversity parameters used were the means of species richness, Shannon diversity (H′), and Pielou evenness (J′) obtained from “bootstrap” sub-samplings of 1,000 trees. Morphometric variables obtained for the fragments included total, edge, and inner areas. Investigation forms were used to survey the history of human interventions and prepare an impacts matrix containing scores assigned to assess the extent, severity and duration of selected impacts. Scores for overall environmental impacts were obtained from the ordination scores produced by a multivariate analysis of the impacts matrix. A multivariate analysis of the standard deviations of soil variables was used to identify the variable which contributed most to soil heterogeneity. The same procedure was repeated for the variables related to topography and ground-water regime. The three species diversity parameters were related to the proportions of edges, the overall impacts scores, and the standard deviations of two selected soil and topographic variables. The species diversity in the fragments increased with increasing heterogeneity of both soil chemical properties and topographic features, and decreased with increasing proportion of forest edges. The evenness component of species diversity also increased with increasing severity of overall environmental impacts. This probably occurred because the 20 fragments did not include highly disturbed forests in the range and the intermediate disturbance effect on species diversity was therefore detected.

Breeding sites of Neotropical Drosophilidae (Diptera): IV. living and fallen flowers of Sessea brasiliensis and Cestrum spp. (Solanaceae)

The flowering phenologies of Sessea brasiliensis and three species of Cestrum (C. amictum, C. schlechtendalii and C. sendtnerianum), all belonging to the Solanaceae, were monitored in a fragment of the montane Atlantic rain forest within São Paulo city from July 1993 through June 1995. A total of 11,021 flies belonging to five species of the flavopilosa group of Drosophila (D. cestri, D. cordeiroi, D. hollisae, D. incompta and D. mariaehelenae), plus 1,244 flies belonging to four species of Zygothrica (Z. dispar, Z. vittimaculosa, Z. vittinubila and Z. aff. vittipunctata) emerged from 33,955 sampled flowers. Cestrum amictum, C. sendtnerianum and Sessea brasiliensis are recorded for the first time as host plants for the species of the Neotropical flavopilosa group ofDrosophila. Additionally, at least ten less abundant taxa belonging also to the Drosophilidae, plus 1,073 microhymenopteran parasitoids (Braconidae, Eucoilidae, and Pteromalidae), emerged from the sampled flowers of S. brasiliensis e Cestrum spp. The present study raised from nine to eleven the number of species of Cestrum previously recorded as breeding sites for these flies. A comprehensive list of species of Solanaceae known to host six species of Drosophila and four species of Zygothrica in southeastern and southern Brazil is included.

Species richness of pteridophytes in a montane Atlantic rain forest plot of Southern Brazil

A floristic survey of pteridophytes (ferns and fern allies) was carried out in a 1ha plot in the Pico do Marumbi State Park, Morretes, State of Paraná, Southern Brazil. The study area is covered with a closed ombrophilous forest (Brazilian Atlantic Forest) and lies approximately 630 m in elevation. All species and life-forms of pteridophytes growing in the plot were registered and most of them were collected for taxonomic identification. A total of 81 species, belonging to 17 families were registered. The richest were Polypodiaceae (12 species), Hymenophyllaceae (11) and Lomariopsidaceae (11). The richest genera were Asplenium (ten species), Elaphoglossum (10) and Trichomanes (six). Life-form composition was: epiphytes (49 species), terrestrials (28), lithophytes (two), epiphytes/terrestrials/lithophytes (one) and epiphytes/lithophytes (one). No hemiepiphytes were found. Terrestrials included herbaceous (22 species), arborescent (four) and climbing (two). Species richness of the plot can be considered as high when compared to other neotropical sites.

Abiotic and vertebrate seed dispersal in the Brazilian Atlantic forest: implications for forest regeneration

This study documents the proportion of woody plant species having different modes of seed dispersal, and classes of seed and fruit size at 16 Atlantic montane forest plots of southeastern Brazil (23–24° S). These plots represent six chronosequences (from 5-year-old to old-growth forest) of forest regeneration following small-scale shifting agriculture. Our results indicate that there is a gradual but predictable increase in the number of woody plant species relying on vertebrate-mediated seed dispersal in increasingly older plots. Moreover, the percentage of plant species bearing small seeds and fruits (< 0.6 cm in length) was more than halved from earlier to older forest plots, while the percentage of plant species producing middle-sized seeds and fruits at least doubled. Plant species belonging to the Melastomataceae, Myrsinaceae, Rubiaceae and Flacourtiaceae comprised a large proportion of the small-seeded and fruit species (33–53%), and largely occurred in early successional forest plots (5–30 years old). In contrast, species belonging to the Myrtaceae and Lauraceae represented most of the species (51–72%) bearing medium-sized seeds and fruits (0.6–1.5 cm in length), and occurred primarily in the old-growth forests. Shifts in the relative importance of dispersal strategies during the regeneration process of Atlantic montane forest, as well as in diaspore size appear to be related to the balance between early successional and shade-tolerant species associated with particular life forms and plant families. Finally, we discuss the relationships between the species richness of Myrtaceae and Lauraceae trees, seed dispersal by medium to large vertebrates, and possible regeneration scenarios for the Atlantic forest.

Four sites with contrasting environmental stress in southeastern Brazil: relations of species, life form diversity, and geographic distribution to ecophysiological parameters

Some ecophysiological parameters related to plant performance and fitness (carbon and nitrogen isotope composition and total C and N concentrations in situ chlorophyll fluorescence measurements) were determined for over 30 species in four habitats bordering the montane Atlantic rain forest of Brazil, along a gradient of altitude and rainfall: a dry coastal forest, two areas of sandy coastal plain vegetation (restingas), and a high altitude campo. There was a considerable diversity of ecophysiological behaviour within and between the functional groups we created based on plant life-forms. For instance, both crassulacean acid metabolism (CAM) and C3species were found in most life-forms sampled and throughout all habitats. Despite the variation in rainfall regimes, average overall water-use efficiency was similar between sites, particularly for C3species, while no clear pattern regarding nitrogen-use emerged in this respect. Acute and chronic photoinhibition were found in many species across this gradient, even in CAM plants. However, on average, chronic photoinhibition and lower energy dissipation capacity were more characteristic of plants from the restinga habitats. This suggests that, although plants colonizing these habitats have evolved features to deal with water shortage, adaptation to high light levels has not been fully achieved yet. The ecophysiological performance of some individual species in distinct habitats and in distinct microhabitats within habitats is also discussed.

Four sites with contrasting environmental stress in southeastern Brazil: relations of species, life form diversity, and geographic distribution to ecophysiological parameters

Some ecophysiological parameters related to plant performance and fitness (carbon and nitrogen isotope composition and total C and N concentrations in situ chlorophyll fluorescence measurements) were determined for over 30 species in four habitats bordering the montane Atlantic rain forest of Brazil, along a gradient of altitude and rainfall: a dry coastal forest, two areas of sandy coastal plain vegetation (restingas), and a high altitude campo. There was a considerable diversity of ecophysiological behaviour within and between the functional groups we created based on plant life-forms. For instance, both crassulacean acid metabolism (CAM) and C3species were found in most life-forms sampled and throughout all habitats. Despite the variation in rainfall regimes, average overall water-use efficiency was similar between sites, particularly for C3species, while no clear pattern regarding nitrogen-use emerged in this respect. Acute and chronic photoinhibition were found in many species across this gradient, even in CAM plants. However, on average, chronic photoinhibition and lower energy dissipation capacity were more characteristic of plants from the restinga habitats. This suggests that, although plants colonizing these habitats have evolved features to deal with water shortage, adaptation to high light levels has not been fully achieved yet. The ecophysiological performance of some individual species in distinct habitats and in distinct microhabitats within habitats is also discussed.

Gap-phase regeneration in a tropical montane forest: the effects of gap structure and bamboo species

To study the influence of gap structure and bamboo species on the regrowth of montane Atlantic forest, colonization by plants was characterized in 30 treefall gaps (30.3–500.5 m2). The study was conducted at Santa Virginia (45°30′ W, 23°17′ S), a 4970-ha reserve of Atlantic montane forest in southeastern Brazil. Area covered by bamboos ranged from 0% to 100% of gap area. Average height of surrounding canopies ranged from 12 to 30 m. As gap are covered by bamboo and average height of surrounding canopies increased, both density and richness of pioneer woody species decreased. Density and richness of shade-tolerant species were negatively influenced by gap area. Low-light-demanding species of Miconia, Leandra and Rapanea accounted for the majority of both pioneer species and individuals sampled, whereas high-light demanding pioneers of Cecropia, Alchornea and Tibouchina were poorly represented. We suggest that in the Atlantic montane forest bamboo species compete for gaps, excluding other light-demanding pioneers. This results in an overall reduction of pioneer species richness in the Atlantic forest.

Effects of habitat fragmentation on plant guild structure in the montane Atlantic forest of southeastern Brazil

Habitat fragmentation is a major cause of biodiversity erosion in tropical forests. The Brazilian Atlantic forest has both high species richness and a long history of anthropogenic disturbance, beginning with colonial agriculture in the sixteenth century. Here we examine the species composition and guild structure of woody plants within five montane Atlantic forest fragments of the Tiet River basin, State of São Paulo, southeastern Brazil, ranging from 5 to 7900 ha in area. We found a negative relationship between fragment size and the relative importance of tree and shrub species that (1) depend on abiotic modes of seed dispersal, (2) are shade-intolerant, and (3) occupy the forest canopy. As fragment size decreased, there was a marked rise in the relative importance of ruderal species, primarily in the Compositae, Euphorbiaceae, Solanaceae, and Leguminosae. There also was a 9% average decline in smaller fragments in relative importance of Myrtaceae, Lauraceae, Sapotaceae, and Rubiaceae, which are the main sources of fleshy fruits for vertebrate frugivores in these forests. Our results suggest that predictable shifts in plant guild structure occur as tropical forest fragments are reduced in size, and that small fragments may become dominated by edges and the surrounding habitat matrix. We suggest that small forest fragments will be unlikely to preserve intact plant and animal assemblages of Brazil's Atlantic coastal forest

A regeneração de uma floresta tropical montana após corte e queima (São Paulo - Brasil)

O corte e queima são um dos tipos de perturbação predominante na floresta Atlântica montana no Sudeste do Brasil. A análise de uma cronosseqüência de regeneração (10, 18, 40 anos e floresta madura) corrobora a hipótese de que as características da floresta se transformam em diferentes velocidades em direção aos valores observados na floresta madura. Em ordem decrescente de velocidade, a floresta, após corte e queima, restaura a riqueza e a diversidade de espécies arbóreo-arbustivas, a composição de guildas, a composição florística (importância relativa das famílias) e, por último, os atributos da estrutura física, com exceção da densidade de indivíduos. A floresta com 40 anos apresentou entre 38,8% e 117,1% dos valores observados na floresta madura, sugerindo que esta se regenera dentro do padrão observado para o conjunto das florestas tropicais. Além da intensidade de perturbação, determinadas características dessa floresta montana, como o tamanho médio de diásporos e a importância relativa de grupos dispersores, podem conferir-lhe maior resiliência. As transformações florísticas direcionais, observadas durante a regeneração, podem ser descritas através de modelos sucessionais compostos por quatro ou cinco fases, dependendo da intensidade de perturbação. Nesses modelos, as espécies dominantes pertencem aos gêneros Imperata, Pteridium, Baccharis, Tibouchina e Alchornea.

Clareiras naturais e a riqueza de especies pioneiras em uma floresta Atlantica montana

A abertura de clareiras naturais, causada pela queda de uma ou mais árvores do dossel, é considerada um mecanismo de manutenção da diversidade de árvores e arbustos nas florestas tropicais. Em um trecho da floresta Atlântica montana no Sudeste do Brasil, foram amostrados todos os indivíduos maiores que 1 m de altura em 30 clareiras (30,3-500,5 m²). Entre as 220 espécies arbóreo-arbustivas amostradas, 24% foram pioneiras, sendo 88,7% de ciclo de vida curto e 11,3% de ciclo de vida longo. Espécies de Miconia, Leandra e Rapanea representaram 49% do total das espécies e 62,1% do total dos indivíduos pioneiros amostrados. No local de estudo, a idade, a área das clareiras, a altura do dossel adjacente e a cobertura de bambu explicaram entre 20% e 73% das variações nas características de ocupação das clareiras por pioneiras. Encontraram-se evidências de que na floresta Atlântica montana: (1) há, em nível de paisagem, riqueza elevada de pequenas árvores e arbustos pioneiros, associados à ocupação e à partição de hábitats iluminados, como as florestas abertas dos topos de morro; (2) a ocupação dos hábitats iluminados por espécies de bambu e bambusóides afeta a densidade, a diversidade e a riqueza local de espécies pioneiras; e (3) fatores ecológicos, como a baixa freqüência de grandes clareiras e daquelas formadas por árvores desenraizadas, são alguns dos fatores responsáveis pela reduzida riqueza local de pioneiras nessa floresta.

Leaf anatomy plasticity of Alchornea triplinervia (Euphorbiaceae) under distinct light regimes in a Brazilian montane Atlantic rain forest

Alchornea triplinervia trees occur in a montane Atlantic rainforest at the Macae de Cima State Ecological Reserve (Nova Friburgo, RJ, Brazil). They are found in two adjacent secondary forests at distinct successional stages: a late-secondary (shaded and humid) and an early-secondary forest (drier, higher light intensities reaching the understory). Leaf samples collected in these environments were compared in regard to various anatomic parameters. Histochemical tests, anatomic measurements and counting indicated no significant variation for the basic leaf anatomy. Nevertheless, as compared to the late-secondary forest, the leaves of the early-secondary forest individuals showed an increased bulk of sclerenchyma at the main nervation and petiole, gelatinous fibers with hygroscopic walls all along the central vascular system, thicker cuticle, a higher abaxial stomatal density, abundance of tannin in the mesophyll, a significantly thicker palisade and spongy parenchyma, and compactation of the spongy parenchyma. This anatomical variation indicates an increased xeromorphism of leaves under the drier conditions of the early-secondary forest. Leaf anatomy plasticity may contribute to the high ecological plasticity of this widespread neotropical species.

An avifaunal survey of the vanishing montane Atlantic forest of southern Bahia, Brazil

SummaryRecent ornithological surveys of humid forest remnants in the Serra da Ouricana near Boa Nova, southern Bahia, Brazil, revealed the existence of an as yet unnoticed montane Atlantic forest avifauna. Among the 220 species recorded, 27 represent range extensions of several hundred kilometres, several others were preceded only by single or a few old, disputed records from Bahia, and at least two are undescribed taxa. A portion of this avifauna has been recorded in other mountainous areas of interior Bahia (Chapada Diamantina, plateau of Maracás), where a complex vegetation mosaic that includes patches of humid forest is found.In addition to the two undescribed passerines, nine other threatened and thirteen near-threatened species have been recorded in the study area. Considered together with the adjoining and also highly endangered “mata-de-cipo”, forest habitats in the Boa Nova area are probably the most neglected habitats in Brazil concerning bird conservation.Levantamentos ornitológicos recentemente feitos em remanescentes florestais úmidos na Serra da Ouricana perto de Boa Nova, sul da Bahia, Brasil, revelaram a existência nessa região de uma avifauna montícola da mata Atlântica. Entre as 220 espécies registradas, estão 27 que tiveram sua área de distribuição estendida por centenas de quilômetros, muitas outras conhecidas da Bahia apenas através de registros antigos e contestados, além de ao menos duas aves não descritas. Parte dessa avifauna foi também registrada em outras áreas montanhosas do interior da Bahia (Chapada Diamantina, Chapadão Maracás), onde se encontra um complexo mosaico de vegetação que inclui manchas de floresta úmida. Além dos dois pássaros não descritos, outras nove espécies ameaçadas e treze quase-ameaçadas foram registradas na área de estudo. Considerando-se em conjunto essa área com a vizinha “mata-de-cipo”, também muito ameaçada, pode-se dizer que os ambientes florestais na região de Boa Nova são os hábitats mais negligenciados em relação à conservação de aves no Brasil.

Reproductive Biology of the Distylous Manettia luteo‐rubra (Rubiaceae)

AbstractThe reproductive biology of Manettia luteo‐rubra was studied in the coastal montane Atlantic rain forest of southeastern Brazil. This Rubiaceae is a perennial vine that flowers all the year round, but has a flowering peak during the dry season. It presents reciprocal herkogamy, thus the plants are morphologically distylous. The morphs occur in a 1:1 ratio, and pollen diameter and corolla length vary between short and long‐styled flowers. Manettia luteo‐rubra displays typical heterostylous self‐incompatibility and sets almost no fruits from self‐ or intramorph pollinations. The flowers are tubular, red with yellow lobes, and odourless. Anthesis is asynchronous, and the flowers last about four days. Concentration of sugars in nectar is similar in both morphs, ca. 24%, this concentration being typical for hummingbird flowers. Three species of hummingbirds are the major pollinators of the flowers of M. luteo‐rubra at the study site: the hermits Phaethornis eurynome and P. squalidus, and the trochiline Thalurania glaucopis. Three species of Heliconius butterflies act as minor pollinators. Both morphs of M. luteo‐rubra exhibit natural fruit‐set of about 80%, this reproductive output being maintained throughout the year by the pollinators' constancy to the flowers.