Structure, diversity, and spatial patterns in a permanent plot of a high Restinga forest in Southeastern Brazil

Abstract

RESUMO(Estrutura, diversidade e padrões espaciais em uma parcela permanente de fl oresta alta de Restinga no Sudeste do Brasil) Nós investigamos a estrutura, diversidade e distribuição de espécies arbóreas em uma parcela de 10,24 ha de uma fl oresta alta de Restinga (FAR) ). A riqueza média foi menor que outros tipos de fl orestas tropicais e outras FAR amostradas em menor intensidade, provavelmente pela juventude e hidromorfi a dos solos na área de estudo. A densidade, área basal, composição e diversidade arbórea variaram consideravelmente de acordo com a classe de tamanho considerada. A parcela estudada teve uma densidade similar a outras fl orestas tropicais, mas com menor área basal (menos indivíduos > 60 cm de diâmetro) e maior densidade de árvores pequenas. Fustes múltiplos não foram frequentes (11% dos indivíduos), mas foram comuns entre as espécies (74% das espécies). A distribuição espacial foi predominantemente agregada, um padrão comum a outros tipos de fl orestas tropicais. Além do substrato arenoso, a parcela estudada e outras fl orestas de areia branca do mundo tiveram padrões muito similares de estrutura, riqueza e diversidade. Assim, consideramos a FAR como um subtipo evidente de fl oresta de areia branca. Palavras ABSTRACT(Structure, composition, and diversity of a high Restinga forest in the Southern Atlantic Forest) We assessed the structure, diversity and distribution of tree species in a 10.24-ha permanent plot of high Restinga forest (HRF) in southeastern Brazil. We sampled 15,040 individuals belonging to 45 families, 87 genera and 116 species (density= 1,468 trees ha -1 , and basal area= 28.0 m 2 ha -1 ). Mean richness was lower than other types of tropical forests and other HRFs that have been less intensively sampled, which is probably due to the younger age and hydromorphy of the soils in the study site. Tree density, basal area, species composition, and diversity all varied considerably depending on the size class considered. The studied plot had a density similar to other tropical forests but with a smaller basal area (fewer individuals > 60 cm in diameter), and higher density of smaller trees. Multi-stemmed individuals were not frequent (11% of the trees), though they were widespread among species (74% of the species). Spatial distribution was predominantly clumped, a pattern common to other types of tropical forests. Besides growing over white-sand soils, the PEIC plot and other white-sand forests of the world also had very similar patterns of community structure, richness and diversity. Therefore, we consider the HRF as a recognizable subtype of white-sand forest.

Responses of water mite assemblages (Acari) to environmental parameters at irrigated rice cultivation fields and native lakes

“…The original vegetation cover is open. It is dominated by herbaceous plants and shrubs that have xerophytic adaptations (Assis et al 2011, Lima et al 2011, together with other associated Atlantic forest elements (Magnago et al 2010). …”

Floristic surveys of Restinga Forests in southern Bahia, Brazil, reveal the effects of geography on community composition

“…The few endemic species observed in Restinga vegetation (Lima et al 2011) probably reflect the more recent origin of its geological substrate (Scarano 2002).…”

“…highlighted by Guedes et al (2006) and Lima et al (2011), and seem to be determined by factors related to their nutrient-poor and well-drained sandy soils (Almeida Jr. et al 2009). Edaphic conditions are therefore presumed to act as 1981; Amorim et al 2008), but less than 4% of Restinga species in Rio de Janeiro State (Araújo 2000).…”

“…Southern and southeastern Restinga sites have been more intensively studied (Lacerda et al 1984;Araújo 2000;Martins et al 2008;Lima et al 2011), although Guedes et al (2006) highlighted our lack of knowledge about the floristic and phytosociological structures of restinga vegetation in São Paulo State. Most of the works produced so far have been limited to floristic and vegetational aspects, with little emphasis on environmental patterns and processes.…”

“…Restingas are highly diverse habitats, although they generally harbor fewer species than other forest types within the Atlantic domain (Almeida Jr. et al 2009;Lima et al 2011). Restinga vegetation is normally established on geologically recent sediments originating from deposition by marine regressive movements during the Pleistocene and Holocene periods.…”