Semideciduous Seasonal Forest Fragment Research Articles

HEIGHT STRUCTURE AND SPATIAL PATTERN OF FIVE TROPICAL TREE SPECIES IN TWO SEASONAL SEMIDECIDUOUS FOREST FRAGMENTS WITH DIFFERENT CONSERVATION HISTORIES

ABSTRACT Anthropogenic disturbances in forests modify survival conditions and development of plants, which has direct effect on the height and spatial structure of tree populations. This study aimed to compare the height structure and spatial pattern of five tree species in two distinct fragments of seasonal semideciduous forest with different histories of conservation. We studied shade-intolerant (Astronium graveolens Jacq., Gallesia integrifolia (Spreng.) Harms) and shade-tolerant species (Chrysophyllum gonocarpum (Mart. & Eichler ex Miq.) Engl., Euterpe edulis Mart. and Holocalyx balansae Micheli). Sixty plots of 100 m2 (10 m x 10 m) were allocated, being 30 contiguous plots in each fragment. All individuals of five species were marked, assessed for total height data and mapped using Cartesian coordinates. We observed differences in height structure between fragments. All populations had a random spatial pattern, except to H. balansae in the less conserved fragment and E. edulis in the conserved fragment that showed a clumped spatial pattern. There were evidences of forest regeneration due to the establishment of shade-tolerant species in less conserved fragment and coexistence of functional groups in both fragments. The height structure and spatial pattern analyses indicating that anthropogenic exploitation changed the environment and population structure in the less conserved area when compared to conserved area. The anthropic exploitation was ceased few years ago, so it is expected that the less conserved fragment reach the stability of an old-growth forest.

Life history ofAdenostemma brasilianum(Pers.) Cass. (Eupatorieae, Asteraceae): A psychophilous herbaceous species of the Brazilian Atlantic Forest understory1

Abstract Adenostemma brasilianum is an herbaceous asteracean pollinated by male Ithomiinae butterflies. These insects feed on the nectar, which contains pyrrolizidine alkaloids, and depend on these compounds for their defense and reproduction. The life history of this species was described from seedlings to the death of adult plants. In addition, we analyzed its reproductive phenology and identified herbivores. The study was conducted in southeastern Brazil, in a semideciduous seasonal forest fragment. Fifty plants with up to two pairs of well-defined leaves were monitored, on which we observed buds, flowers, dispersed diaspores, and herbivores. We labeled 140 capitula in the bud stage and monitored them from anthesis of the first flowers to diaspore dispersal. Adenostemma brasilianum is biennial and monocarpic, and establishes a seedling bank within about 9 months (from February to October, in the first year of life). Plant mortality resulting from physical damage was high (46%) at the beginning of the r...

Biologia reprodutiva de Cordiera macrophylla (K. Schum.) Kuntze (Rubiaceae), espécie dioica da região sudoeste do Estado de Mato Grosso, Brasil

RESUMO O gênero Cordiera (Rubiaceae) possui aproximadamente 25 espécies e ampla distribuição no Brasil. Seus representantes são árvores ou arbustos dioicos, com flores funcionalmente unissexuadas. Este estudo foi realizado em dois fragmentos de Floresta Estacional Semidecidual, no município de Tangará da Serra, MT. Foram investigadas a fenologia reprodutiva, a razão sexual, a morfologia e a biologia floral, o sistema e o sucesso reprodutivo. Cordiera macrophylla floresceu de julho a setembro, durante a estação seca, com pico sincrônico entre flores pistiladas e estaminadas. Flores estaminadas florescem antecipadamente e por um período mais prolongado que as pistiladas. A antese das flores pistiladas apresentou maior longevidade. A razão sexual foi de 1:1. Flores estaminadas são dispostas em inflorescências umbeliformes e as pistiladas são unifloras, ambas semelhantes morfologicamente. Os frutos são bagas verrucosas, polispérmicas. A taxa de formação de frutos por polinização natural foi de 95%, evidenciando a dependência dos polinizadores para a manutenção da espécie. O sucesso reprodutivo também foi alto, confirmando que a associação entre morfologia e biologia floral favoreceu a espécie nas áreas estudadas.

Regrowth in post-fire area in a fragment of semideciduous seasonal forest in Viçosa-MG

The sprouting is the typical response of pointers to death of trees as a result of fire, courts, diseases or physiological disorders. The present work aimed to study the regrowth ability of species remaining trees in a Seasonal Forest Semidecidual degraded by fire and assess the importance of resprouting ability in the area of recovery. The fire resulted in the destruction of 12 hectares of native vegetation, with differential levels of degradation. The study focused on the section where the effect of the fire was more severe, with total destruction of the vegetation cover. The area a complete survey of all species showing budding was performed. The diameter (cm) at the base of the bud, using a caliper, and the height (m) of the sprout with the aid of a tape was measured. It was observed that the sprouting capacity varies with the tree species and the size/age of the plant. Mabea fistulifera and Dalbergia nigra showed a higher number of shoots; Anadenanthera macrocarpa and Piptadenia gonoacantha the greatest height and diameter, the first of which also had the highest number of shoots per array; Aegiphila sellowiana showed high potential for regrowth both the stem and the roots. The widespread occurrence of grasses, especially the grass ( Melinis minutiflora ) represents a physical impediment and reduces the brightness to the by sprouting roots. Additional keywords: budding; forest fire; natural regeneration; secondary succession.

Florística e Fitossociologia de uma Floresta Estacional Semidecidual, Reserva Privada Osununú-Misiones, Argentina

O estudo foi realizado em um fragmento de Floresta Estacional Semidecidual (Misiones, Argentina), com o objetivo de analisar as variáveis fitossociológicas das espécies arbóreas, por meio da estratificação da área de acordo com a geomorfologia. Inicialmente, baseando-se na declividade e por meio de fotointerpretação, a área foi compartimentalizada em: planície, encostas com declividade média, encostas com declividade alta e topo. Dentro de cada compartimento, foram alocados três conglomerados compostos de quatro subunidades de 100 m2, totalizando 48 subunidades, nas quais foram incluídas todas as árvores com circunferência à altura do peito ≥ 10 cm, sendo também medidas a profundidade do solo e a declividade. Foram amostradas 72 espécies, 59 gêneros e 31 famílias. Foi possível detectar variações das espécies e dos valores de importância, obtidos de acordo o gradiente topográfico. Na Análise de Correspondência Canônica, os valores de cobertura das espécies mostraram ter uma correlação significativa com os parâmetros profundidade de solo e declividade.

Community ecology of epiphytic Bromeliaceae in a remnant of Atlantic Forest in Zona da Mata, Minas Gerais State, Brazil

The present study aimed to document the composition, richness, diversity as well as horizontal and vertical distribution of epiphytic Bromeliaceae in a fragment of submontane seasonal semideciduous forest in Minas Gerais State (-21°38'15''S, -43°10'55''W). Three plots (semicircles with a radius of 25 m) were marked and we found 72 phorophytes that harbor 15 species of epiphytic Bromeliaceae, distributed in nine genera. Nidularium azureum (L.B.Sm.) Leme is local endemic, and considered critically endangered. In general, the richness is higher than other larger areas of seasonal semideciduous or even ombrophilous forests. Some differences concerning composition, diversity and richness among the plots were found and must be due to microhabitat conditions. Trunks supported most occurrences (101 out of 246) and Tillandsia stricta Sol. ex Sims had the highest frequency on the phorophytes. The values of H’ = 2.34 and J = 0.87 must be considered similar or even higher than some ombrophilous forests.

Estrutura, composição florística e caracterização sucessional em remanescente de Floresta Estacional Semidecidual no Sudeste do Brasil

Este estudo foi realizado em remanescente de Floresta Estacional Semidecidual (FES), localizado em Sorocaba (SP, Brasil), com o objetivo de verificar seu estágio sucessional e inferir sobre a composição futura. A hipótese deste artigo previa que esse remanescente apresentaria regeneração com baixa diversidade de espécies, predomínio de espécies pioneiras de dossel, ausência de espécies residentes no sub-bosque e predomínio de espécies anemocóricas e autocóricas. Foi utilizado o método de parcelas, considerando os indivíduos em três classes de tamanho, duas delas referentes ao sub-bosque e uma ao dossel (1 -<100 cm; 2 - >100 cm e circunferência à altura do solo <15 cm; 3 - CAP >15 cm). Foram amostradas 146 espécies, sendo os maiores valores de diversidade encontrados no dossel e nas espécies de sub-bosque da classe 2. A similaridade entre as três classes foi baixa. Das espécies com maior valor de importância, cinco são pioneiras e cinco são não pioneiras, e as espécies com maiores valores de regeneração natural são consideradas como não pioneiras e residentes. Contrariando a hipótese inicial, essas características, somadas ao predomínio de espécies zoocóricas nas três classes, indicam que o remanescente está em estágio intermediário de sucessão e possui condições microclimáticas para a entrada e permanência de espécies que necessitam de áreas mais sombreadas. Espécies como Aspidosperma olivaceum, Cordia trichotoma, Ocotea elegans e Guarea guidonia, consideradas não pioneiras e transitórias, foram amostradas somente nas classes 1 e 2, indicando a futura substituição de espécies e o avanço sucessional do remanescente.

Estimativa do estoque de biomassa em um fragmento florestal usando imagens orbitais

Este trabalho teve como objetivo estimar a biomassa aérea de um fragmento de Floresta Estacional Semidecidual, situada no município de Viçosa-MG, através de imagens ortorretificadas do satélite IKONOS. Com base em dados de inventário florestal, conduzido em 15 parcelas de 1000 m² (20 m × 50 m), foram obtidas as estimativas dos estoques de biomassa aérea, a partir de equações alométricas. Estas estimativas foram relacionadas com variáveis digitais (reflectância nas quatro bandas multiespectrais e em 12 índices de vegetação), extraídas das imagens digitais, empregando-se Redes Neurais Artificiais (RNA). Os resultados mostraram que, para as condições da área de estudo, o emprego da técnica de RNA com apenas as bandas 1, 2, 3 e 4 do satélite IKONOS como variáveis de entrada foi eficiente para estimar a biomassa aérea total, embora os resíduos tenham sido ainda menores quando foram utilizadas as quatro bandas e os 12 índices de vegetação.

Phoresy byAmerichernesAff.Incertus(Pseudoscorpiones: Chernetidae) on a Tropical FlyFannia canicularis(Diptera: Fanniidae) in a Fragment of the Atlantic Forest, Brazil

Pseudoscorpions employ phoresy for dispersal, in which one animal attaches to another for transportation. This study documents the occurrence and phoresy by Americhernes aff. incertus (Pseudoscorpiones: Chernetidae) on the fly Fannia canicularis (Diptera: Fanniidae) in a fragment of semi-deciduous seasonal Atlantic Forest, in the state of Pernambuco, northeast Brazil. The pseudoscorpions were found attached to the ventral surface of six individual flies. To our knowledge, no previous studies have shown the presence of Americhernes aff. incertus in the northeast Atlantic Forest and its use of flies as a dispersal method.

Fitossociologia da regeneração natural de um fragmento urbano de Floresta Estacional Semidecidual (Juiz de Fora, MG)

Urban forests are an important component of the landscape, being responsible for the conservation of biodiversity in the cities. This study aimed to analyse the phytosociological structure of regenerating tree species in a small urban (2 ha) semideciduous seasonal forest fragment at Juiz de Fora, MG, Brazil. The survey was done on 25 plots of 5 x 5 m, where all the individuals with diameter at breast height (DBH) 1 m were sampled. The number of individuals found was 1066, belonging to 71 species with the predominance of ‘pioneiras’ (47% of species and 69% of individuals). The most representative species were Myrcia splendens, Anadenanthera colubrina, Vismia guianensis, Miconia theizans and the exotic invasive Syzygium jambos, which together amounted 40.5% of the total value of importance. The Shannon diversity index was 3.17 nats. ind-1 and Pielou equability index was 0.74, indicating the existence of an ecological dominance. The detrended correspondence analysis (DCA) detected the presence of strong floristic gradient, associating some shading species (Anadenanthera colubrina and Piptadenia gonoacantha) with exotic Coffea arabica. Even with 70 years of natural regeneration, the results indicated a regenerating community with difficulties of progression to advanced successional stages.

Allophylus exappendiculatus(Sapindaceae), a New Species from Rio De Janeiro, Brazil

A new species Allophylus exappendiculatus Somner, Ferrucci & Frazão (Sapindaceae) from a remnant fragment of seasonal semideciduous forest in Rio de Janeiro, Brazil, is here described and illustrated. It can be distinguished from other known species of Allophylus by the simple axillary thyrses closely arranged at the base of young shoots, and by the petals without appendages or rarely with vestigial ones. It is here compared with its putative closest relatives A. edulis and A. puberulus. In addition, the micromorphological characters of the pollen grains are described. Allophylus exappendiculatus is a narrow endemic currently known from six collections from the municipalities of Engenheiro Paulo de Frontin, Itaguaí and Santa Maria Madalena.

Mammals of a forest fragment in Cambuci municipality, state of Rio de Janeiro, Brazil

The Atlantic Forest is considered a hotspot due to its current state of vast degradation and high indexes of biodiversity. This biome has been degraded through the years by processes resulting from the Brazilian socioeconomic model of development. The seasonal semi-deciduous Atlantic Forest is a poorly studied phytophysiognomy specially degraded by human activities in the state of Rio de Janeiro. In the present study we report the results of a rapid mammalian inventory conducted in the municipality of Cambuci, in a fragment of seasonal semi-deciduous forest. We used live traps and pitfall traps to capture non-volant small mammals, and mist-nets of different lengths to collect bats. To sample medium and large-sized mammals we used camera traps. We recorded 27 mammal species in the region, of which 16 are volant mammals. We emphasize the distribution extension of Trinomys setosus in 150 km (that enabled its insertion in the species list of Rio de Janeiro) and the capture of Lonchophylla peracchii, a recently described species apparently restricted to Atlantic Forest. Both facts show the importance of the fragment for the region biodiversity.

Seasonal variation of consumption of the species used as fruit source by brown howler monkeys (Alouatta clamitans) in southern Brazil

Considering the seasonal variation of fruits availability in seasonal semideciduous forests, this study analyzed whether the richness of fruit species exploited by Alouatta clamitans is higher in the rainy period rather than the dry one. Plant species consumed were investigated by visualization and feces analysis, from July 2005 to June 2006, in a seasonal semideciduous forest fragment in Paraná state, Brazil. Ten species of fruits were consumed during the rainy period and 13 during the dry period: three were consumed exclusively during the rainy period; six exclusively during the dry period; and seven in months that covered both dry and rainy periods. The number of fruit species consumed during the rainy period was considerably lower than the expected richness. Moreover, among fruit species consumed during the rainy period, only four bear fruits mainly in this period of the year, the other species bear fruits in great part of it. Therefore, the selectivity of A. clamitans was mainly directed to species capable of providing fruits along the year, prioritizing these species even when other fruit sources are available.

Leaf dimorphism of <i>Microgramma squamulosa</i> (Polypodiaceae): a qualitative and quantitative analysis focusing on adaptations to epiphytism

The epiphytic fern Microgramma squamulosa occurs in the Neotropics and shows dimorphic sterile and fertile leaves. The present study aimed to describe and compare qualitatively and quantitatively macroscopic and microscopic structural characteristics of the dimorphic leaves of M. squamulosa, to point more precisely those characteristics which may contribute to epiphytic adaptations. In June 2009, six isolated host trees covered by M squamulosa were selected close to the edge of a semi-deciduous seasonal forest fragment in the municipality of Novo Hamburgo, State of Rio Grande do Sul, Brazil. Macroscopic and microscopic analyzes were performed from 192 samples for each leaf type, and permanent and semi-permanent slides were prepared. Sections were observed under light microscopy using image capture software to produce illustrations and scales, as well as to perform quantitative analyses. Fertile and sterile leaves had no qualitative structural differences, being hypostomatous and presenting uniseriate epidermis, homogeneous chlorenchyma, amphicribal vascular bundle, and hypodermis. The presence of hypodermal tissue and the occurrence of stomata at the abaxial face are typical characteristics ofxeromorphic leaves. Sterile leaves showed significantly larger areas (14.80cm2), higher sclerophylly index (0.13g/cm2) and higher stomatal density (27.75stomata/mm2) than fertile leaves. The higher sclerophylly index and the higher stomatal density observed in sterile leaves are features that make these leaves more xeromorphic, enhancing their efficiency to deal with limited water availability in the epiphytic environment, compared to fertile leaves.

Assemblage of medium and large size mammals in an urban Semideciduous Seasonal Forest fragment in Cerrado biome

Nowadays, the processes of deforestation and loss of habitats represent a major threat to many species of mammals. These processes cause changes in natural landscapes by decreasing area, connectivity, and fragment size, and increasing edge effects and number of fragments. Understanding which and how many species persist in disturbed fragments may indicate the species' minimum requirements and might contribute to their conservation. Here we show how the mammalian fauna of medium and large size (higher than 1 kg) are structured in a semideciduous seasonal forest fragment of 36.5 ha in the urban area of Jataí, Goiás. We performed the sampling with 30 sand track plots (1 x 1 m). We analyzed the relative record frequency and built a collector's curve to demonstrate the sampling effort. With a total effort of 600 track plots × days, we recorded twelve species of mammals with our tracks sampling method, from which only the wild mammals were included in the analyzes (11 species). The estimated species richness reached 13 species (SD (Standard Deviation) = ±1, CI (Confidence Interval) = ±2 (11 – 15 species). The species with the highest relative record frequency was Didelphis albiventris and the species with the lowest was Tamandua tetradactyla. The fragment size must be a limiting factor to the richness and to the occurrence of species, as it may not be sufficient to allow the persistence of a population or an individual. Disturbances that originated from houses, like domestic animals and movement of people, also contributed to the removal and extinction of species. To conserve the species in the fragment, we suggest the prevention of entrance of people and of domestic animals. We also recommend increased connectivity of the fragment with the landscape external to the urban area in order to allow the movement of the currently present species.

Water availability determines the richness and density of fig trees within Brazilian semideciduous forest landscapes

The success of fig trees in tropical ecosystems is evidenced by the great diversity (+750 species) and wide geographic distribution of the genus. We assessed the contribution of environmental variables on the species richness and density of fig trees in fragments of seasonal semideciduous forest (SSF) in Brazil. We assessed 20 forest fragments in three regions in Sao Paulo State, Brazil. Fig tree richness and density was estimated in rectangular plots, comprising 31.4 ha sampled. Both richness and fig tree density were linearly modeled as function of variables representing (1) fragment metrics, (2) forest structure, and (3) landscape metrics expressing water drainage in the fragments. Model selection was performed by comparing the AIC values (Akaike Information Criterion) and the relative weight of each model (wAIC). Both species richness and fig tree density were better explained by the water availability in the fragment (meter of streams/ha): wAICrichness = 0.45, wAICdensity = 0.96. The remaining variables related to anthropic perturbation and forest structure were of little weight in the models. The rainfall seasonality in SSF seems to select for both establishment strategies and morphological adaptations in the hemiepiphytic fig tree species. In the studied SSF, hemiepiphytes established at lower heights in their host trees than reported for fig trees in evergreen rainforests. Some hemiepiphytic fig species evolved superficial roots extending up to 100 m from their trunks, resulting in hectare-scale root zones that allow them to efficiently forage water and soil nutrients. The community of fig trees was robust to variation in forest structure and conservation level of SSF fragments, making this group of plants an important element for the functioning of seasonal tropical forests.

<i>Calvatia guzmanii sp. nov.</i> (Agaricaceae, Basidiomycota) from Paraná State, Brazil

A new species of Calvatia is described from a semideciduous seasonal forest fragment in the western region of Paraná State, southern Brazil. Calvatia guzmanii is proposed as new based on the combination of dark brown and spiny to velvety exoperidium, prominent subgleba and echinulate-reticulate basidiospores with a short pedicel. A comparison with morphologically similar Calvatia species is giv

Forest Fragments Surrounded by Sugar Cane Are More Inhospitable to Terrestrial Amphibian Abundance Than Fragments Surrounded by Pasture

In recent years, there has been increasing interest in matrix-type influence on forest fragments. Terrestrial amphibians are good bioindicators for this kind of research because of low vagility and high philopatry. This study compared richness, abundance, and species composition of terrestrial amphibians through pitfall traps in two sets of semideciduous seasonal forest fragments in southeastern Brazil, according to the predominant surrounding matrix (sugar cane and pasture). There were no differences in richness, but fragments surrounded by sugar cane had the lowest abundance of amphibians, whereas fragments surrounded by pastures had greater abundance. The most abundant species,Rhinella ornata, showed no biometric differences between fragment groups but like many other amphibians sampled showed very low numbers of individuals in fragments dominated by sugar cane fields. Our data indicate that the sugar cane matrix negatively influences the community of amphibians present in fragments surrounded by this type of land use.

Amplifiability of mitochondrial, microsatellite and amelogenin DNA loci from fecal samples of red brocket deer Mazama americana (Cetartiodactyla, Cervidae)

We tried to amplify mitochondrial, microsatellite and amelogenin loci in DNA from fecal samples of a wild Mazama americana population. Fifty-two deer fecal samples were collected from a 600-ha seasonal semideciduous forest fragment in a subtropical region of Brazil (21°20'S, 47°17'W), with the help of a detection dog; then, stored in ethanol and georeferenced. Among these samples 16 were classified as "fresh" and 36 as "non-fresh". DNA was extracted using the QIAamp(®) DNA Stool Mini Kit. Mitochondrial loci were amplified in 49 of the 52 samples. Five microsatellite loci were amplified by PCR; success in amplification varied according to locus size and sample age. Successful amplifications were achieved in 10/16 of the fresh and in 13/36 of the non-fresh samples; a negative correlation (R = -0.82) was found between successful amplification and locus size. Amplification of the amelogenin locus was successful in 22 of the 52 samples. The difficulty of amplifying nuclear loci in DNA samples extracted from feces collected in the field was evident. Some methodological improvements, including collecting fresh samples, selecting primers for shorter loci and quantifying the extracted DNA by real-time PCR, are suggested to increase amplification success in future studies.

Estrutura e grupos ecológicos de um remanescente florestal urbano com histórico de perturbação recente em Uberlândia, MG

Structure and ecological groups of an urban, recently disturbed, forest remnant in Uberlândia, MG. The goal of this work was to evaluate the biological diversity in an urban forest remnant to better understand the structure of the community and ecological processes that are important for the conservation of these fragile ecosystems. The study was carried out in a fragment of seasonal semideciduous forest, with a long history of