Composição da flora vascular em um remanescente de floresta montana no semi-árido do nordeste do Brasil

Abstract

-(Floristic composition of a vascular flora in a remnant of montane forest placed of the semi-arid region of Northeastern Brazil). The montane forests (altitude > 600 m) at the semi-arid of Northeastern Brazil are surrounded by non forest thorn deciduous vegetation (caatinga), showings distinct flora and plant physionomy. They occur in upper mountains due to special climatic condition, originated by altitude. As the literature shows that the flora of these forests also varies according to the degree of humidity, a floristic survey was carried out in a humid montane forest located at Parque Ecológico João Vasconcelos-Sobrinho, city of Caruaru, Pernambuco, in order to compare the results with other montane forests in the region. We registered 332 species/subspecies of 85 families. Fabaceae, Asteraceae, Rubiaceae, Solanaceae and Myrtaceae were the richest families. Comparative analysis with other montane forest show that the proportion of tree species decrease and bushes increase as increasing the distance of the Atlantic coast. Key words: Brejo de altitude, floristic survey, habit, humid forest RESUMO -(Composição da flora vascular em um remanescente de floresta montana no semi-árido do nordeste do Brasil). As florestas montanas (altitude > 600 m) do semi-árido do nordeste do Brasil são rodeadas por vegetação não florestal caducifólia espinhosa (caatinga), apresentando flora e fisionomia distintas. Ocupam as áreas mais elevadas de determinados relevos, a depender da condição climática criada pela da altitude. Considerando que a literatura mostra que a flora daquelas florestas varia conforme o grau de umidade do ambiente, foi realizado o levantamento da flora vascular da floresta montana úmida do Parque Ecológico João Vasconcelos-Sobrinho, Caruaru, Pernambuco, com objetivo de comparar os resultados com outras florestas montanas da região. Foram registradas 332 espécies/subespécies pertencentes a 85 famílias. Fabaceae, Asteraceae, Rubiaceae, Solanaceae e Myrtaceae foram as famílias com maior número de espécies. A análise comparativa com outras florestas montanas indica que a proporção de espécies de árvores na flora total diminui e a de arbustos e subarbustos aumenta à medida que essas serras se distanciam do litoral. Palavras-chave: Brejo de altitude, floresta úmida, hábito, levantamento florístico 1. Universidade Federal Rural de Pernambuco, Departamento de Biologia, Av. Dom Manoel de Medeiros, s.n., Dois Irmãos, 52171-900Recife, PE, Brasil 2. Autor para correspondência: mrodal@terra.com.br IntroduçãoDe acordo com Swaine et al. (1990), em qualquer latitude, a distribuição das florestas ocorre onde o balanço entre precipitação e evapotranspiração é positivo. Além disso, sabe-se que os conceitos de florestas úmida e seca variam de acordo com os diferentes autores e com as regiões fitogeográficas onde ocorrem essas florestas e que o grau de sazonalidade das florestas cresce com o aumento do número de meses secos por ano e decresce com o aumento da precipitação anual (Richards 1996, Lüttge 1997.Apesar da lite...

Serra do Urubu, a biodiversity hot-spot for angiosperms in the northern Atlantic Forest (Pernambuco, Brazil)

“…The Serra do Urubu has the biggest taxonomic richness (832 taxa) when compared with other floristic surveys in the state of Pernambuco (Table 2) (Guedes 1998;Rodal et al 2005aRodal et al , 2005bRodal and Sales 2007;Sacramento et al 2007;Ferraz and Rodal 2008;Cavalcanti 2012;Alves et al 2013). The Serra do Urubu slightly exceeds the total number of species only an area of lowland forest in the north of the state, whose inventory has been continuously updated since 2008 and was recently updated to 830 species of angiosperms (Alves-Araújo et al 2008;Melo et al 2011;Alves et al 2013).…”

“…The difference is even more striking when the data presented here are compared with floristic inventories of areas of submontane and montane forests of Pernambuco (Rodal et al 2005b;Rodal and Sales 2007;Ferraz and Rodal 2008), even after considering the Melo et al | Angiosperms of the Serra do Urubu, Pernambuco, Brazil cataloged over 10 years of sampling effort. This region stands as the most species-rich area in northeastern Brazil (Amorim et al 2008).…”

“…On the other hand, in studies carried out in Pernambuco by Rodal et al (2005b), Rodal and Sales (2007) and Ferraz and Rodal (2008), Orchidaceae was poorly sampled and represented only 3.2-1.5% of the flora, while in the Serra do Urubu Orchidaceae represents 10.3% of the total number of species recorded. A proportion similar to this has been shown for areas of Bahia, wherein Orchidaceae account for between 8.2% and 10.2% of the flora (Amorim et al 2009;Coelho and Amorim 2014;Leitman et al 2014).…”

“…Fabaceae emerges at different proportions in the various studies performed in Atlantic Forest fragments, despite being one of the most representative families in montane areas of Pernambuco (Rodal et al 2005b;Rodal and Sales 2007;Ferraz and Rodal 2008) and Bahia (Amorim et al 2005(Amorim et al , 2009Coelho and Amorim 2014). In the Serra do Urubu, the family accounts for about 6.1% of total species, while in the Mata do Brejão (Rodal et al 2005b) and the Municipal Park Vasconcelos Sobrinho (Rodal and Sales 2007), its proportion ranges from 12-15.6%.…”

“…These inventories point out the taxonomic diversity that ranges from 101 to 830 species, demonstrating the high species richness of some areas (Cavalcanti 2012;. Inventories that include areas of submontane and montane forests (above 100 m altitude) in the state are scarcer (Rodal et al 2005b;Barreto et al 2006;Grillo et al 2006;Rodal and Sales 2007;Ferraz and Rodal 2008); they document the number of angiosperm species as between 69 and 375.…”