Diversity, community structure and conservation status of an Atlantic Forest fragment in Rio de Janeiro State, Brazil

Abstract

The State of Rio de Janeiro still holds unknown portions of the Atlantic Forest, which represent gaps in the knowledge of this ecosystem. Paracambi and neighbor municipal districts comprise a vast stretch of virtually unknown forest that makes up part of the Serra do Mar biodiversity corridor. The following study describes the tree community structure in a stretch of the ombrophilous Atlantic Forest, in the Parque Natural Municipal do Curió (Curio MNP), Paracambi, Rio de Janeiro, which serves as the basis to evaluate species diversity and conservation status. The altitudes in the area ranges from 100 to 690 m and the climate varies from mild subtropical to tropical hot and humid. Forty plots (10x10m) were randomly placed along the area, where all the stems equal to or greater than five centimeters (5 cm) diameter at breast high from ground level were measured. A total of 749 individuals, pertaining to 128 genera and 210 species were recorded, eight of which are listed as threatened of extinction in the Brazilian flora. The Shannon-Weaver diversity index (H′) was 4.7 nat.ind.-1 and the species with greater importance value was Pseudopiptadenia contorta (1.6460 m2; 18 individuals) while the most common species wereSenefeldera vertcilata (48) and Actinostemon verticilatus (47 individuals). Despite the sample area being a little smaller than that commonly adopted in tropical studies, data pointed to a richness hitherto not registered in any other study for the State of Rio de Janeiro, no matter the inclusion criteria used, and also confirmed by the two estimator indices used, which have revealed very similar results. The vertical forest structure, the values associated to the successional stage of the species and other aspects of community structure indicate that the Curio MNP encompasses forest stretches in advanced stages of ecological succession. Besides its key location for the connectivity of forest fragments in the region, the results emphasize the ecological importance of this forest remnant and the need for its conservation.

Distribuição diamétrica de espécies da Floresta Ombrófila Densa no Sul do Estado do Rio de Janeiro

“…O PNM Curió possui uma área total de 913 ha, com altitude variando de 53 a 672 m a.n.m. (Cysneiros et al, 2015). Sua cobertura vegetal é representada predominantemente pela Floresta Ombrófila Densa Submontana (IBGE, 2012), com predomínio de formações secundárias, em diferentes estágios de regeneração.…”

“…Radlk. (Cysneiros et al, 2015), comparando-as com a distribuição da comunidade florestal, caracterizada pelo conjunto de todas as espécies amostradas no levantamento fitossociológico.…”

Justicia paracambi, a new Brazilian species of Acanthaceae

“…The fragment is mostly woody and covered in Atlantic rain forest (Cysneiros et al 2015). The main aim of this park is to protect local rich water resources, as it is permeated by small rivers, streams and contains some seasonal wetlands.…”

“…This area is protected, being part of the Parque Natural Municipal do Curió (Municipal Natural Park of Curió), which is mainly occupied by a rich forest with most of it in an excellent state of conservation (Fraga et al 2012, Cysneiros et al 2015. It forms part of a forest continuum between the Reserva Biológica do Tinguá (Tinguá Biological Reserve), in the northeast, and the Parque Estadual Cunhambebe (Cunhambebe State Park) in the southeast of the State.…”

Pedoforms Microclimate and Seasonal Forest Structure in Médio Vale do Paraíba

“…They also provide knowledge on species richness and diversity (Felfili et al, 2011). In spite of their applications, most of the phytosociological studies in the region are merely descriptive (Carvalho et al, 2007;Cysneiros et al, 2015;Dan et al, 2010;Ivanauskas et al, 1999;Ivanauskas et al, 2000;Medeiros et al, 2016). Therefore, the influence of environmental variables on the dynamics of ecosystems should be further discussed, especially about the structure and floristic composition of Semideciduous Seasonal Forest arboreal communities.…”