Ecologia de epífitas vasculares em áreas verdes urbanas na Zona da Mata, Minas Gerais, Brasil

Urbanization is a growing and ever-changing process and the urban green areas represent a shelter for nature. Epiphytes are plants that grow upon other plants without parasitizing them, that is, without removing any nutrients from them, and their presence in urban areas, despite the lack of studies, helps in assessing the environmental quality of the city and its surroundings. The aims of the study were to characterize the composition, structure and floristic diversity of the vascular epiphytic component in 26 urban green areas of 14 municipalities, located in the Juiz de Fora Microregion, Zona da Mata of Minas Gerais State; to investigate the floristic similarity between the areas and to evaluate the importance of environmental variables on this composition. The following hypotheses were tested: 1) the community of epiphytes will present low richness and diversity of species due to the susceptibility of this synusia to anthropogenic disturbances; 2) there will be low beta diversity due to the homogenization of the flora of the urban environment, which tends to present a reduced set of species that are more tolerant to such disturbances. In order to evaluate the community were calculated the relative and absolute frequencies, Shannon diversity index (H’) (compared through the Hutcheson t test) and Pielou equability (J'). A cluster analysis through UPGMA using Jaccard index was performed to evaluate the floristic similarity, and the relationship between the floristic composition and environmental variables were evaluated through a canonical correspondence analysis (CCA). A total of 110 epiphyte species were sampled in 26 green areas. Two Bromeliaceae species have the highest absolute frequencies: Tillandsia recurvata (L.) L. (68,8%) and T. tricholepis Baker (65.3%), together accounting for a relative frequency of 48,8%. Other four species worth mentioning due to the high frequency: the Polypodiaceae Microgramma squamulosa (30,8%), Pleopeltis astrolepis (19,4%) and P. pleopeltifolia (14,1%), and Rhipsalis lindbergiana (Cactaceae) (13,6%). The remaining species occurred in less than 10% of the sampled phorophytes. The H’ index value for the 26 areas was 2.44, and J' was 0.58, showing the dominance of the aforementioned species. In general, the MJF green area pairs presented Jaccard similarity index values higher than 25%, which is sufficient to consider the similar floristic composition between the areas. The CCA showed as important the following variables: average cloud cover, annual temperature variation, average annual temperature, evapotranspiration seasonality and elevation. It is possible to notice the homogeneity of the MJF epiphytic flora, probably due to the selection of tolerant species to the anthropic disturbance in the urban environment. Some results suggest that is necessary more comprehensive studies about the epiphytes in urban environment, like Orchidaceae as the richest family (once generally is poor in the such environment), better definition of the patterns of species distribution both regarding the anthropized environments and the relationships with exotic or native phorophytes, as well as to enhance the knowledge of the ecological functions played by the epiphytes in these places.A urbanização é um processo crescente e em constante estado de mudança e as áreas verdes no ambiente urbano apresentam-se como um abrigo da natureza. Epífitas são plantas que crescem sobre outras plantas sem parasitá-las, ou seja, sem retirar delas nenhum tipo de nutriente, e sua presença em zonas urbanas, apesar de ainda pouco estudada, pode auxiliar na avaliação da qualidade ambiental da cidade e seu entorno. Objetivou-se caracterizar a composição, estrutura e diversidade florística do componente epifítico vascular em 26 áreas verdes urbanas de 14 municípios da Microrregião de Juiz de Fora, Zona da Mata do estado de Minas Gerais; investigar a similaridade florística entre as áreas e avaliar a importância de variáveis ambientais e aspectos da urbanização sobre essa composição. Foram testadas as seguintes hipóteses: 1) a comunidade de epífitas vasculares apresentará baixa riqueza e diversidade de espécies devido a suscetibilidade desta sinúsia aos distúrbios antropogênicos; 2) haverá baixa diversidade beta devido à homogeneização da flora do ambiente urbano, que tende a apresentar um conjunto reduzido de espécies que são mais tolerantes a tais distúrbios. Para se avaliar a estrutura da comunidade foram calculadas frequências relativa e absoluta, índice de diversidade de Shannon (H’) (comparados através do teste t de Hutcheson) e uniformidade de Pielou (J). Para avaliar a similaridade florística foi conduzida uma análise de agrupamento através de UPGMA, e o índice de similaridade de Jaccard, e a relação entre a composição florística e as variáveis ambientais foi avaliada através de uma análise de correspondência canônica (CCA). Foi amostrado um total de 110 espécies de epífitas nas 26 áreas verdes. A família mais rica foi Orchidaceae, diferentemente do que é comumente encontrado em áreas verdes urbanas. Duas espécies de Bromeliaceae se destacaram com as maiores frequências absolutas: Tillandsia recurvata (68,8%) e T. tricholepis (65,3%) que, somadas, apresentaram frequência relativa de 48,8%. Outras quatro espécies merecem destaque pela frequência apresentada: as Polypodiaceae Microgramma squamulosa (30,8%), Pleopeltis astrolepis (19,4%), P. pleopeltifolia (14,1%) e Rhipsalis lindbergiana (Cactaceae) (13,6%). As demais espécies ocorreram em menos de 10% dos forófitos amostrados. O valor do índice de H’ para as 26 áreas foi 2,44 e de J' foi 0,58, demonstrando dominância das espécies supracitadas. De modo geral os pares de áreas verdes da MJF apresentaram os valores do índice de similaridade de Jaccard superior a 25%, suficiente para se considerar a composição florística similar entre as áreas. A CCA apontou como importantes as seguintes variáveis: média de cobertura de nuvens, variação da temperatura anual, média de temperatura anual, sazonalidade de evapotranspiração e elevação. É possível perceber a homogeneidade da flora epifítica da MJF, provavelmente causada pela seleção de espécies tolerantes à perturbação antrópica no ambiente urbano. Alguns resultados sugerem a necessidade de estudos mais abrangentes sobre as epífitas em ambiente urbano, como Orchidaceae ser a família mais rica (uma vez que geralmente é pobre em tal ambiente), melhor definição dos padrões de distribuição das espécies tanto com relação aos ambientes antropizados quanto com os forófitos exóticos e nativos, assim como conhecer melhor a funções ecológicas desempenhadas pelas epífitas nestes locais

EpIG‐DB: A database of vascular epiphyte assemblages in the Neotropics

Vascular epiphytes are a diverse and conspicuous component of biodiversity in tropical and subtropical forests. Yet, the patterns and drivers of epiphyte assemblages are poorly studied in comparison with soil‐rooted plants. Current knowledge about diversity patterns of epiphytes mainly stems from local studies or floristic inventories, but this information has not yet been integrated to allow a better understanding of large‐scale distribution patterns. EpIG‐DB, the first database on epiphyte assemblages at the continental scale, resulted from an exhaustive compilation of published and unpublished inventory data from the Neotropics. The current version of EpIG‐DB consists of 463,196 individual epiphytes from 3,005 species, which were collected from a total of 18,148 relevés (host trees and ‘understory’ plots). EpIG‐DB reports the occurrence of ‘true’ epiphytes, hemiepiphytes and nomadic vines, including information on their cover, abundance, frequency and biomass. Most records (97%) correspond to sampled host trees, 76% of them aggregated in forest plots. The data is stored in a TURBOVEG database using the most up‐to‐date checklist of vascular epiphytes. A total of 18 additional fields were created for the standardization of associated data commonly used in epiphyte ecology (e.g. by considering different sampling methods). EpIG‐DB currently covers six major biomes across the whole latitudinal range of epiphytes in the Neotropics but welcomes data globally. This novel database provides, for the first time, unique biodiversity data on epiphytes for the Neotropics and unified guidelines for future collection of epiphyte data. EpIG‐DB will allow exploration of new ways to study the community ecology and biogeography of vascular epiphytes

ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

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. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ