Influence of edaphic variables on the floristic composition and structure of the tree-shrub vegetation in typical and rocky outcrop cerrado areas in Serra Negra, Goiás State, Brazil

Abstract

Influence of edaphic variables on the floristic composition and structure of the tree-shrub vegetation in typical and rocky outcrop cerrado areas in Serra Negra, Goiás State, Brazil ABSTRACT -(Influence of edaphic variables on the floristic composition and structure of the tree-shrub vegetation in typical and rocky outcrop cerrado areas in Serra Negra, Goiás State, Brazil). The present study analyzed the influence of edaphic variables on the floristic compositions and structures of the arboreal and shrub vegetation of typical cerrado (TC) and rocky outcrop cerrado (RC) communities in the Serra Negra mountain range in Piranhas Municipality, Goiás State, Brazil. Ten 20 × 50 m plots were established in each community, and all individuals with minimum diameters ≥ 5 cm measured at 30 cm above soil level were sampled. Composite soil samples were collected at 0-20 cm depths in each plot for physical and chemical analyses. The proportions of above-ground rock cover work also estimated in each RC plot. A total of 2,009 individuals (83 species, 69 genera, and 34 families) were recorded. Qualea parviflora was the only species consistently among the 10 most structurally important taxa in both communities, and was considered a generalist species. The observed and estimated species richnesses were greater in RC than in TC, although plant basal areas and heights did not differ between them. There were positive correlations between rock cover × plant density and rock cover × basal areas. TWINSPAN and PCA analysis separated the TC and RC plots, and three RC habitat specialist species (Wunderlichia mirabilis, Norantea guianensis, and Tibouchina papyrus) were identified. Soil variables were found to have greater effects on the species compositions of the TC and RC sites than the geographic distances between sampling plots. According to CCA analysis, the exclusive (or more abundant species) of each community were correlated with soil variables, and these variables therefore determined the selection of some species and influenced the differentiation of the vegetation structures of the communities studied.

Effects of past climate variability on fire and vegetation in the cerrãdo savanna of the Huanchaca Mesetta, NE Bolivia

“…The cerrãdo biome comprises forest, savanna, and campestre (open-field) formations (Abreu et al, 2012;Mistry, 1998). Cerrãdo sensu stricto is characterized as a woody savanna formation composed of dense, thin, and rocky outcrops with cerrãdo physiognomies that are distinguishable based on their densities, heights, and scattered tree-shrub covers with roughly 50 % trees and 50 % grass (Abreu et al, 2012).…”

“…Cerrãdo sensu stricto is characterized as a woody savanna formation composed of dense, thin, and rocky outcrops with cerrãdo physiognomies that are distinguishable based on their densities, heights, and scattered tree-shrub covers with roughly 50 % trees and 50 % grass (Abreu et al, 2012). The principal determinants of the growth and development of the cerrãdo vegetation types are largely related to edaphic factors (Colgan et al, 2012).…”

Influência dos Afloramentos Rochosos sobre a Comunidade Lenhosa no Cerrado stricto sensu

“…Este resultado corrobora o encontrado por Abreu et al (2012), em que, apesar de encontrarem menores densidades no cerrado com afloramentos rochosos, os valores de área basal e de altura dos indivíduos não diferiram entre o cerrado típico e o cerrado com afloramentos rochosos. No entanto, o resultado deste trabalho contraria a sugestão de Kurtz & Araújo (2000) de que os afloramentos rochosos podem limitar o porte dos indivíduos lenhosos, assim como contraria a afirmação de Ribeiro & Walter (2008) de que, em trechos de cerrado com afloramentos rochosos, a densidade de indivíduos é variável e dependente da quantidade de rochas.…”

“…Porém, pouco se sabe sobre a correlação entre a cobertura de rochas e as informações florísticas e estruturais da vegetação lenhosa em ambientes rupestres no Cerrado (Scarano, 2007;Abreu et al, 2012). Diante da necessidade de pesquisas sobre a vegetação lenhosa de ambientes rupestres no Cerrado e para subsidiar projetos de conservação e recuperação desta fisionomia, este estudo tem como objetivo verificar como os afloramentos rochosos influenciam os padrões da composição florística e a estrutura fisionômica das espécies lenhosas, além de constatar se existem espécies indicadoras de um tipo específico de ambiente.…”

Structure and floristic relationships between Cerrado sensu stricto sites on two types of substrate in northern Cerrado, Brazil

“…Gomes et al (2011) and Abreu et al (2012) compared the Cerrado sensu stricto flora and structure on different substrates. Such authors concluded that, at local scale, the floristic and structure difference between Cerrado Rupestre and other types of Cerrado sensu stricto is reflex of the substrate on the selection of specialist species in habitats which prefer soils with rocky outcrops, dominating the community structure.…”