RESUMO -(Sinopse das Orchidaceae terrestres ocorrentes no litoral norte do Rio Grande do Sul, Brasil). Realizou-se estudo taxonômico de Orchidaceae terrestres em uma região natural do Rio Grande do Sul, o litoral norte, entre a encosta abrupta da Serra Geral e a linha da costa do Oceano Atlântico (29°10'S a 30°00'S). A área de estudo apresenta clima subtropical úmido do tipo Cfa. Médias anuais de temperatura e precipitação variam de 17,5 a 20,0 °C e de 1.200 a 1.700 mm, respectivamente. A vegetação natural, embora grandemente reduzida e modificada por atividades humanas, é fortemente relacionada às pequenas variações topográficas que afetam a drenagem dos solos. Um total de 42 espécies, incluindo duas novas ocorrências para o Estado, distribuídas em 24 gêneros, foi confirmado como resultado de citações bibliográficas, revisão de herbários e coleta extensiva ao longo da área de estudo. A maioria dos gêneros (17) apresenta uma única espécie, e somente um gênero (Habenaria) concentrou número alto de espécies (8). Os resultados taxonômicos incluem uma nova combinação taxonômica, chaves de identificação para gêneros e espécies, observações taxonômicas e ecológicas, e material examinado. Palavras-chave: Orchidaceae, vegetação litorânea, taxonomia, Rio Grande do Sul, BrasilABSTRACT -(Synopsis of terrestrial Orchidaceae from the north coast of Rio Grande do Sul, Brazil). A taxonomic survey of terrestrial Orchidaceae from the northern coastal plain of Rio Grande do Sul was carried out. This region lies between the steep slopes of the Serra Geral and the Atlantic Ocean (29°10'S; 30°00'S). The study area has a moist subtropical Cfa-type climate. Mean annual temperatures vary from 17.5 to 20.0 °C, and precipitation varies from 1,200 to 1,700 mm. The natural vegetation is closely associated with small-scale topographic variation, which in turn affects soil drainage. It has been greatly reduced and modified by human activities. A total of 42 species belonging to 24 genera were identified based on the literature, herbarium specimens and extensive collecting throughout the study area. Two species are cited for the first time in Rio Grande do Sul. Many genera (17) were represented by a single species, while only one genus (Habenaria) had a relatively high number of species (8). Results include a new taxonomic combination, identification keys for genera and species, taxonomic and ecological observations, and citation of herbarium vouchers.

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.

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Abstract:The phylogenetic relationship among species may influence the mechanisms controlling local community assembly in ecological time. We analyzed the degree of recurrence of phylogenetic structure patterns in woody plant communities distributed along grassland-forest ecotones, across different vegetation types in southern Brazil, and the effect of phylogenetic pool size used to assess such patterns. Species frequency in quadrats distributed along grassland-forest ecotones was surveyed in different phytogeographic regions, where forests tend to expand over grasslands. We used principal coordinates of phylogenetic structure (PCPS) to evaluate the structure within vegetation quadrats divided into three habitat categories: grassland, forest edge and forest interior. Furthermore, phylogenetic structure measures were computed using different phylogenetic pool sizes. Our analyses showed consistent patterns in relation to habitat categories and to different phylogenetic pool sizes. Basal clades of angiosperms were associated with forest areas, while late-divergence clades were associated with grasslands. These results suggest that grasslands act as phylogenetic habitat filters to forest woody species, independently of species composition at each site and the phylogenetic pool. Rosanae and Asteranae act as vanguards of forest expansion over grasslands, while Magnolianae species tend to be restricted to forest. Our results shed light on the organization of ecological systems, providing evidence of recurrent phylogenetic structure patterns in ecotone plant communities at regional scale. Nomenclature:The International Plant Names Index.Abbreviations: PCPS -Principal Coordinates of Phylogenetic Structure.

Abstract:Plant facilitation can improve the diversity of plant communities in several ecosystems, especially in stressful environments. The establishment of tree species on rocky outcrops can be limited by several biotic and abiotic factors. The richness and abundance of forest trees species on rocky outcrops surrounded by a large forest remnant in south Brazil were correlated with the cover of Bromelia balansae, a spiny stoloniferous species commonly occurring at forest–grassland transitions. Sixty plots were established on three flat rocky outcrops (20 in each). In each plot the coverage of bromeliads was estimated into three classes (0%, 1–50% and 51–100%) and all seedlings (individuals 10–30 cm in height) were counted and identified. ANOVAs with randomization tests were performed to establish the effect of different bromeliad cover classes on the richness and abundance of seedlings. The cover of bromeliads was positively related to the richness and abundance of young pioneer tree species. Evidence suggests that B. balansae can act as a nurse plant for tree seedlings, but manipulative experiments are needed to confirm this.

Terrestrial orchids comprise a taxonomically and ecologically varied group, ranging from tropical to subpolar regions and from wet marshy to dry sand‐dune environments. An ecological survey of these plants was performed in a natural region of Rio Grande do Sul, south Brazil, namely the northern coastal plain, between the abrupt slopes of the Serra Geral and the coastal line of the Atlantic Ocean (29°01′S to 30°00′S, 49°43′W to 50°16′W). The study area presents a humid subtropical climate of the Cfa type. Mean annual temperature and precipitation range from 17.5 to 20.0°C and from 1200 to 1700 mm, respectively. The occurrence of indigenous terrestrial orchid species was recorded for six major habitats or vegetation types: bogs and marshes, peat forests, rain forests, dune forests, Butia‐palm stands and coastal sand‐dunes. The ecological range was defined for 39 species belonging to 23 genera, based on literature, herbarium revisions and extensive collecting along the studied area. Species richness ranged from nine species, in both coastal dunes and palm‐groves, to 17 species in peat forests. A negative correlation was observed between species richness and ecological range, showing a general tendency for terrestrial orchids to be confined to one or a few habitats. Multivariate analyses indicated light (herbaceous vs woody vegetation) as a primary ecological factor, and soil drainage (sandy vs peaty substrates) as a secondary factor controlling terrestrial orchid distribution.

The objective of this work was to estimate the repeatability coefficients of mangaba (Hancornia speciosa) fruit traits, in order to define the number of fruit needed for an accurate selection of superior genotypes, as well as to conjecture about the nature of the phenotypic variation of these traits. Evaluations were performed for 160 fruit of 16 genotypes from two native H. speciosa populations of Goiás Velho and Padre Bernardo, in the state of Goiás, Brazil. Repeatability was estimated by the analysis of variance, principal component analyses based on covariance and on the correlation matrix, and structural analysis based on the correlation matrix. Repeatability estimates for fruit weight, diameter, and length, as well as seed number and weight, were of low magnitude, from 0.02 to 0.62, indicating low heritability. Repeatability estimates for ºBrix, titratable acidity, and ºBrix/acidity ratio were higher, from 0.34 to 0.91, indicating a low to potentially moderate heritability. The number of fruit for an effective selection of the best genotypes for titratable acidity, ºBrix, ºBrix/acidity ratio, and fruit weight is four for a 0.85 accuracy level. However, seven fruit would allow 0.90 accuracy for the same traits, and 0.85 accuracy for fruit length and diameter. The number and weight of seed per fruit are not effective for predicting the real value of a genotype.

A cobertura florestal em Santa Catarina encontra-se reduzida e fragmentada e entre as tipologias florestais mais fortemente afetadas está a Floresta Estacional Decidual. Com objetivo de conhecer a composição e estrutura do componente arbóreo de um fragmento de Floresta Estacional foram demarcadas unidades amostrais de 20 x 20 m, totalizando 0,4 ha. As espécies arbóreas com circunferência à altura do peito (CAP) ≥ 25 cm foram avaliadas e identificadas. Foram amostrados 205 indivíduos, de 54 espécies, distribuídas em 44 gêneros e 23 famílias. A estimativa da diversidade arbórea pelo índice Shannon-Weaver (H') resultou em 3,472 (nats) e a equabilidade de Pielou (J') em 0,870. As famílias com maior número de espécies foram Fabaceae, Myrtaceae, Meliaceae, Lauraceae e Sapindaceae e as espécies com as maiores densidades e coberturas foram Nectandra megapotamica (Spreng.) Mez, Sorocea bonplandii (Baill.) W.C. Burger, Lanjouw & Boer e Ocotea diospyrifolia (Meisn.) Mez. A riqueza e diversidade da amostra situam-se como intermediárias entre aqueles obtidos para fragmentos de Florestas Estacionais Deciduais, nos levantamentos do Inventário Florístico Florestal de Santa Catarina, evidenciando impacto da exploração e fragmentação nesta formação. Apesar do contexto, a área estudada conserva importante parcela das espécies citadas para essa tipologia florestal.