Hoehnea 44(1): 123-138, 6 tab., 4 fig., 2017 http://dx.doi.org/10.1590/2236-8906-57/2016 Diversity, vertical structure and floristic relationships of vascular epiphytes in an urban remnant of the Brazilian Atlantic Forest Lucas Deziderio Santana1, Samyra Gomes Furtado1, Camila Nardy1, Felipe Silveira Leite2 and Luiz Menini Neto3,4 Received: 21.6.2016; accepted: 23.01.2017 ABSTRACT - (Diversity, vertical structure and floristic relationships of vascular epiphytes in an urban remnant of the Brazilian Atlantic Forest). This study was conducted in a fragment of montane seasonal semi-deciduous forest (Minas Gerais State) with a history of anthropogenic disturbance. Our goals were to characterise the composition, structure and floristic diversity of vascular epiphytes and to investigate the floristic similarities of the community with other areas of urban seasonal forests in Brazil. We sampled 61 phorophytes with 47 epiphytic species. The richest families were Bromeliaceae (seven) and Polypodiaceae (seven). The most common ecological category was accidental holoepiphytes with 21 species - an unprecedented result for the Neotropical region. The Shannon index was 2.95 and the Pielou evenness index 0.77, showing a relatively high diversity with a few dominant species and numerous rare species. Similarity analyses showed a longitudinal gradient and strong influence of the distance from the ocean on floristic relationships as well as influence of dense ombrophilous forests on the composition of the vascular epiphytes of the surveyed area. Keywords: accidental holoepiphytes, biodiversity hotspot, multivariate analyses, taxonomic diversity, urban forest RESUMO - (Diversidade, estrutura vertical e relações florísticas de epífitas vasculares em um remanescente urbano da Floresta Atlântica brasileira). Este estudo foi realizado em um fragmento de floresta estacional semidecidual montana (Minas Gerais) com histórico de perturbação antrópica. Os objetivos foram caracterizar a composição, estrutura e diversidade florística das epífitas vasculares e investigar a similaridade florística da comunidade com outras áreas de florestas estacionais urbanas no Brasil. Foram amostrados 61 forófitos e registradas 47 espécies de epífitas. As famílias mais ricas foram Bromeliaceae (sete) e Polypodiaceae (sete). A categoria ecológica mais comum foi a de holoepífitas acidentais com 21 espécies - um resultado inédito na Região Neotropical. O índice de Shannon foi 2,95 e o índice de uniformidade de Pielou foi 0,77, mostrando diversidade relativamente alta com certa dominância de poucas espécies, enquanto as espécies raras foram numerosas. Análises de similaridade mostraram gradiente longitudinal e forte influência da distância do oceano sobre as relações florísticas, assim como influência das florestas ombrófilas densas sobre a composição das epífitas vasculares na área estudada. Palavras-chave: análises multivariadas, diversidade taxonômica, floresta urbana, holoepífitas acidentais, “hotspot” de biodiversidade Introduction of maintaining remnants in urban areas. Such urban forests are considered important agents of the Tropical forests are characterised by warm and local microclimate “by reducing the pollution and humid climates with little variation of temperature maintaining the temperature”, and they present great and marked stratification (Ricklefs 2011). In terms aesthetical value and importance to human welfare of epiphytes, they are the richest forests in the world, (Bolund & Hunhammar 1999, Bonametti 2003, amassing more than 60% of all species (Biedinger & Mckinney 2008). Urbanisation results in disturbance, Fischer 1996). However, due to population growth and changes in the environmental conditions are and the need for territorial expansion, these forests evident and conducive to biotic modifications, for are heavily fragmented, reinforcing the importance instance, in species composition (Mckinney 2008). 1. Universidade Federal de Juiz de Fora, Programa de Pós-graduação em Ecologia, 36036-930 Juiz de Fora, MG, Brasil 2. Universidade Federal de Juiz de Fora, Curso de Ciências Biológicas, 36036-930 Juiz de Fora, MG, Brasil 3. Centro de Ensino Superior de Juiz de Fora, Rua Luz Interior 345, Estrela Sul, 36030-776 Juiz de Fora, MG, Brasil 4. Corresponding author: [email protected] 124 Hoehnea 44(1): 123-138, 2017 However, few scientific studies have concentrated on This study aimed to contribute to our knowledge urban environments (Marris 2009). about epiphytic synusia in an urban forest through Vascular epiphytes are plants not connected to characterisation of the composition, structure and the soil or connected during only one life stage, using floristic diversity of vascular epiphytes in a remnant the phorophytes as support without parasitizing them of a seasonal semi-deciduous forest in the Atlantic through haustoria (Madison 1977). This synusia has domain. In addition, we investigated the floristic great ecological importance, providing resources, similarity of this community with other areas such as fruits, nectar, pollen and water to the fauna composed of urban seasonal forests in the same and microhabitats to several animal groups (Benzing phytogeographic domain. Based on data available 1990). Vascular epiphytes are represented by about in the literature, we tested the following hypotheses: 29,000 species, or 10% of all vascular flora, distributed 1) the study area has low richness and diversity of in 876 genera and 84 families (Zotz 2013). Globally epiphytic species, suggesting that urban areas tend to seen, the Orchidaceae, Araceae and Bromeliaceae are be more susceptible to human impacts (McKinney the richest families (Gentry & Dodson 1987, Zotz 2006, 2008); 2) the specific and generic composition 2013). The Brazilian Atlantic forest, an important and the proportion of ecological categories tend to be global biodiversity hotspot (Myers et al. 2000), similar between urban areas as some species are more exhibits similar configuration of the richest epiphyte tolerant to anthropogenic stresses (Barthlott et al. families, with about 2,256 species, mainly distributed 2001, Bermudez et al. 2009); 3) Because humidity is in the Orchidaceae (46.5%), Bromeliaceae (26.2%), an important factor for the establishment of epiphytes Polypodiaceae (4.3%) and Araceae (4.2%) (Freitas (Johansson 1974, Benzing 1990), the areas closer to et al. 2016). the ocean are clustered by separating those that are Knowledge about this synusia in Brazilian urban farther away from the ocean. environments must still be considered as scarce, although a growing number of studies have been Materials and methods published in the last ten years, but concentrated in Brazil’s South Region (e.g., Dislich & Mantovani Study area - The study was conducted at the edge of 1998, Dittrich et al. 1999, Gonçalves & Waechter an urban fragment of secondary montane seasonal 2003, Borgo et al. 2002, Fabricante et al. 2006, Hefler semi-deciduous forest (SSF) (Veloso et al. 1991) & Faustioni 2004, Dettke et al. 2008, Geraldino et al. in altitudes ranging from 670-750 m.s.m. in an area 2010, Oliveira et al. 2013, Alves et al. 2014, Becker of about 87 ha belonging to the Botanical Garden et al. 2015, Furtado & Menini Neto 2015). This reflect of the Federal University of Juiz de Fora in the our knowledge about the epiphytic flora as a whole, municipality of Juiz de Fora, Zona da Mata of Minas since the majority of studies have also been conducted Gerais (21°44'S, 43°22'W) (figure 1). This fragment in South Brazil (Kersten 2010). Since a reduction of is close to the environmental protection area Mata do the anthropogenic pressure on the environment is Krambeck (MK) which encompasses about 300 ha rather unlikely in the near future (Hietz 1999), the and is composed of continuous secondary forest on a composition of epiphytes needs to be investigated former coffee crop plantation. Regeneration processes in different environments, such as isolated trees, have been taking place for the last 70 years, although plantations and urban forests, in order to develop the area is frequently under strong anthropogenic effective conservation strategies. pressure from the surrounding municipalities, such as Thus, the present study was conducted in order selective logging and introduction of exotic species to expand our knowledge about the epiphytic flora in (Fonseca & Carvalho 2012). urban environments in Brazil’s Southeastern Region. According to the Köppen classification, the The municipality of Juiz de Fora, located southeast climate in the region is Cwa, with dry and cold winters of Minas Gerais, represents a suitable area to perform and rainy and warm summers. Mean annual rainfall such a study. It is well connected to the other regions of is about 1,500 mm, with higher rates during January the Serra da Mantiqueira and integrates the Corredor (~300 mm) (PMJF 2014). Mean annual temperature Sudeste (southeastern corridor) of the Atlantic Forest, is about 18.9 °C, the hottest and coldest months are which characterises it as a region of “very high” February (21.7 °C) and July (16.1 °C), respectively biological importance (Drummond et al. 2005). (PJF 2014). Santana et al.: Ecology of vascular epiphytes in an urban forest 125 Figure 1. Location of the Mata do Krambeck and the other 10 areas used in multivariate analyses. Field and laboratory work - Field surveys were and the Atlantic forest; 4) occurring in the three or conducted from August to November 2013. We more phytogeographic domains (wide distribution); analysed