RESUMO -(Fitossociologia de dois trechos inundáveis de Matas de Galeria no Distrito Federal, Brasil). As Matas de Galeria do biomaCerrado possuem peculiaridades fisionômicas e florísticas que permitem separá-las em dois subtipos: "não-inundável", quando em solos bem drenados; e "inundável", o subtipo menos estudado, em solos mal drenados. O presente trabalho objetivou caracterizar estrutural e floristicamente dois trechos inundáveis das matas dos córregos Acampamento (15°35'S; 48°10'W) Palavras-chave: fitossociologia, diversidade, mata de galeria, Riacho Fundo, Acampamento, Distrito Federal ABSTRACT -(Phytosociology of two swamped portions of gallery forests in Distrito Federal, Brazil). Gallery forests in the Cerrado biome possess physiognomic and floristic peculiarities that allow its division in two subtypes: "non-swamp" located in well drained soils; and "swamp" the less studied subtype, located in badly drained soils. The present study aimed to characterize the structure and the flora of two swamped portions in the gallery forests of the Acampamento stream (15°35'S; 48°10'W) and the Riacho Fundo stream (15°55'S and 48°02'W), both in Distrito Federal (DF). In each forest it was allocated a grid of 160×50 m (0.8 ha), composed by 40 plots of 10×20 m (200 m 2 ). All the individuals with DBH ≥ 3.0 cm were surveyed, including the standing dead plants. It was sampled 6,078 individuals, being 3,030 in the swamped portion of Acampamento stream (33 families, 49 genera and 60 species) and 3,048 in the Riacho Fund portion (30 families, 41 genera, 53 species). The basal area (dominance) and the diversity (H') for the studied portions were 47.96 m 2 /ha and 2.99 nats/ind. (Acampamento) and 41.28 m 2 /ha and 2.84 nats/ind. (Riacho Fundo), respectively. If compared to others gallery forests previously studied in Distrito Federal, such diversity values are considered low, although they are similar to that indicated for the "Swamp Forests" ("Matas de Brejo") of southeastern Brazil. The similarity indexes of Sørensen (58.0%) and Morisita (70.6%) point to high qualitative and quantitative similarity among portions. However the classification accomplished by TWINSPAN generated two distinct groups, each one linked to one of the portions studied (Acampamento and Riacho Fundo). These results reinforce previous indications that distinct gallery forests in Distrito Federal, or even similar portions on that, show different floristic patches. This variation are related to the hydrographic basin in which the gallery forest is inserted, and the soil drainage.

RESUMO -Fragmentos de Floresta Ombrófila Mista têm sido freqüentemente utilizados para o manejo de bovinos na região do médio rio Pelotas, Sul do Brasil. Para avaliar o efeito dos animais na estrutura populacional de Araucaria angustifolia, Clethra scabra, Dicksonia sellowiana e Maytenus ilicifolia, foram amostrados sítios, sujeitos à alta e baixa intensidade de pastoreio, em cinco fragmentos, utilizando-se parcelas de 20 x 20 m. Apesar do pequeno tamanho dos fragmentos e da alta perturbação pelo manejo do gado e pela extração seletiva de madeira, as espécies ocorreram em abundância, e a densidade de plântulas e infantis foi maior do que de árvores. O efeito do gado na estrutura das populações de A. angustifolia variou em função das características ambientais de cada fragmento, não havendo, assim, um padrão na resposta das populações estudadas ao pastoreio. Com relação às demais espécies, os resultados não foram conclusivos, pois ocorreram em alta densidade apenas em um fragmento.Palavras-chave: Espécies ameaçadas, heterogeneidade ambiental e conservação in situ. EFFECT OF CATTLE GRAZING ON PLANT POPULATION STRUCTURE IN ARAUCARIA FOREST FRAGMENTS

Epiphytes are hyper‐diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non‐vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer‐reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non‐vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non‐vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events.

Recebido em 28/12/2004. Aceito em 1/09/2005 RESUMO -(Comparação do método de parcelas com o "levantamento rápido" para amostragem da vegetação arbórea do Cerrado sentido restrito). Desde os anos 1960 o Cerrado sofre uma perda agressiva de área pelas atividades antrópicas. Visando acumular informações botânicas de forma ágil, projetos nesta região adotaram um método de amostragem expedita da vegetação, denominado "levantamento rápido" (LR). O objetivo deste estudo foi comparar e analisar a aplicação do LR com um método de parcelas, muito utilizado neste bioma. O trabalho foi realizado em um trecho de Cerrado sentido restrito na Fazenda Água Limpa, DF, Brasil (15°56'S -47°46'W). Para o LR foram aplicadas três linhas de caminhada (L1, L2 e L3), registrando-se em intervalos de cinco minutos a presença das espécies inéditas que fossem encontradas. Isto permitiu a construção de uma curva espécies×tempo. Para possibilitar uma comparação direta, L1 foi coberta com 11 parcelas amostrais de 20×50 m, alocadas sobre um trecho estruturalmente homogêneo, amostrando-se todos os indivíduos com diâmetro a 30 cm de altura do solo ≥ 5cm. Quarenta minutos foi o tempo máximo para estabilizar uma curva espécie×tempo individual (L2). Pelo LR foram identificadas 67 espécies, 53 gêneros e 32 famílias, enquanto nas parcelas foram identificadas 58 espécies, 45 gêneros e 27 famílias, distribuídas entre os 1.132 indivíduos amostrados. O tempo necessário para concluir a amostragem por parcelas foi de 8 horas e 17 minutos, enquanto o método rápido encerrou-se em 110 minutos. Comparando apenas L1 (concluída em 35 minutos) com parcelas, os resultados florísticos revelaram diferenças, que são analisadas à luz das características de cada método. O LR requisita técnicos com ampla experiência de campo, tendo se mostrado eficiente para registrar a riqueza do trecho estudado, com mais rapidez que as parcelas. Entretanto, LR não fornece informações estruturais da vegetação e suas sugestões de abundância são meramente especulativas. Porém, pela velocidade e facilidade de aplicação, pelo custo baixo, e pelo esforço mínimo de campo, o LR deve ser considerado como uma valiosa ferramenta para auxiliar na conservação do Cerrado. Palavras-chave: levantamento rápido, parcelas, fitossociologia, árvores, CerradoABSTRACT -(Comparison of the plot method with "rapid survey" for sampling the arboreal vegetation of Cerrado stricto sensu). The Cerrado biome has lost much of its area through human activity, and its degradation has been increasing since the 1960s. With the aim of gathering botanical information as efficiently as possible, research projects in the region have been using a fast sampling method called the rapid survey, but these methods are still the target of much academic criticism. Our aim was to compare the rapid survey with the plot method most commonly used in Central Brazil. The study was carried out in a section of Cerrado s. str. vegetation in the Federal District, Brazil, using the rapid survey along three lines (L1, L2 and L3). Walking along ea...

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In situ and ex situ plant conservation Environmental assessment Model validation a b s t r a c t Species occurrence and abundance models are important tools that can be used in biodiversity conservation, and can be applied to predict or plan actions needed to mitigate the environmental impacts of hydropower dams. In this study our objectives were: (i) to model the occurrence and abundance of threatened plant species, (ii) to verify the relationship between predicted occurrence and true abundance, and (iii) to assess whether models based on abundance are more effective in predicting species occurrence than those based on presence-absence data. Individual representatives of nine species were counted within 388 randomly georeferenced plots (10 m × 50 m) around the Barra Grande hydropower dam reservoir in southern Brazil. We modelled their relationship with 15 environmental variables using both occurrence (Generalised Linear Models) and abundance data (Hurdle and Zero-Inflated models). Overall, occurrence models were more accurate than abundance models. For all species, observed abundance was significantly, although not strongly, correlated with the probability of occurrence. This correlation lost significance when zero-abundance (absence) sites were excluded from analysis, but only when this entailed a substantial drop in sample size. The same occurred when analysing relationships between abundance and probability of occurrence from previously published studies on a range of different species, suggesting that future studies could potentially use probability of occurrence as an approximate indicator of abundance when the latter is not possible to obtain. This possibility might, however, depend on life history traits of the species in question, with some traits favouring a relationship between occurrence and abundance. Reconstructing species abundance patterns from occurrence could be an important tool for conservation planning and the management of threatened species, allowing scientists to indicate the best areas for collection and reintroduction of plant germplasm or choose conservation areas most likely to maintain viable populations.

Natural tree regeneration in abandoned pastures can be hampered by various biotic and abiotic filters, including seed removal and predation. We tested the effects of maintenance and removal of grass and seed deposition (buried and unburied) on seed germination of 12 tree species in dry forest pastures. We obtained evidence supporting the hypothesis that seeds attain higher germination under a grass canopy than on bare ground. For most species, grass cover provides safety from seed predators and facilitates germination by providing a suitable microclimate with soil humidity similar to the forest. The hypothesis that buried seeds attain higher germination was not supported by our data. Predation and removal of unburied seeds ranged from 0 to 77 % and, alone or together, were the major causes of non‐germination. Direct seeding is a promising technique for revegetation of recently abandoned pastures in areas originally covered by tropical dry forests. The high germination rate of seeds deposited on the ground and under grass reduces costs during initial restoration stages, potentially facilitating the spread and use of this technique.