Floristic and phytosociological analysis of palm swamps in the central part of the Brazilian savanna

Abstract

We analyzed the fl oristics and phytosociology of three palm swamps in the municipality of Bela Vista de Goiás, located in the state of Goiás, Brazil, in the central part of the Brazilian savanna (Cerrado). Th e fl oristic surveys were conducted monthly from May 2008 to April 2009, and 310 species were recorded (seven bryophytes, 15 ferns and 288 angiosperms). Bryophytes belonged to fi ve genera and fi ve families; ferns belonged to nine genera and nine families; and angiosperms belonged to 134 genera and 45 families. Th e angiosperm families with the highest species richness were Poaceae, Cyperaceae, Asteraceae, Eriocaulaceae, Xyridaceae, Lentibulariaceae, Melastomataceae, Rubiaceae and Fabaceae. Th e palm swamps were divided into three zones of increasing humidity: edge, middle and core. Th e number of species was higher in the middle than at the edge and the core. Th e families with the highest cover values were Cyperaceae, Melastomataceae, Arecaceae and Poaceae. Although the palm swamps had been disturbed to varying degrees, those disturbances did not aff ect the fl ora in the middle or the core. Floristic similarity was high between these two zones within a given palm swamp and low between the edges of diff erent palm swamps. Acta Botanica Brasilica 27(1): 205-225. 2013. IntroductionWetlands are environments in which water is the determining factor of abiotic and biotic conditions (Keddy 2000, Steinke & Saito 2008. Th ese areas support several typical animal and plant species and foster a large number of ecological processes that sustain those species (Maltchik et al. 2003), making wetlands some of the most productive environments on the planet (Steinke & Saito 2008).In the Brazilian savanna (Cerrado), despite the dominance of phytophysiognomies on well-drained soils, wetlands such as palm swamps also occur (Meireles et al. 2002). Palm swamps are communities composed of a continuous herb-grass layer, which occupies most of their area, and a tree-shrub layer dominated by individuals of the palm Mauritia fl exuosa L. f. (local name, buriti), with a canopy cover of between 5% and 10% (Ribeiro & Walter 2008).In addition to the diversity of plant species (Araújo et al. 2002, Guimarães et al. 2002, palm swamps present some distinct micro-ecosystems in which there are some plant-animal interactions that are still poorly understood (Oliveira et al. 2009). Th ese environments serve as refuges, food sources and reproduction sites for the aquatic and terrestrial fauna of the adjacent phytophysiognomies (Guimarães et al. 2002). Th ey are also sites of great scenic beauty with economic and sustainable potential for ecotourism and for extractivism involving species such as M. fl exuosa and Syngonanthus nitens (Bong.) Ruhland (capim-dourado, which means "golden grass") by small rural communities (Schmidt et al. 2008).Palm swamps are categorized as areas of permanent preservation, for ensuring the maintenance of springs and the quality of watercourses (Araújo et al. 2002). Although legally protected, palm swamps ha...

Veredas da região sudeste: peculiaridades florísticas e estruturais e situação de conservação

“…The Brazilian Forest Code defines veredas as a "savanna vegetation type found in hydromorphic soils, with palm tree Mauritia flexuosa without forming canopy, among clusters of shrub and herbaceous species" (Brasil, 2012). This classification where the veredas appears as a grassy field in the presence of M. flexuosa palms is prevalent and observed in the studies in central region of Brazil, in Goiás (Resende et al, 2013), in the Distrito Federal (Meirelles et al, 2002) and the region of Triângulo Mineiro (Minas Gerais State) Guimarães et al, 2002;Oliveira et al, 2009;Ramos et al, 2014;Rosolen et al, 2015).…”

“…Despite the predominance of well-drained soils in the phytophysiognomy, the Cerrado also features wetlands, as the palm swamps (with Mauritia flexuosa L. f.), which are known as veredas in Brazil (Resende et al, 2013;Padovesi-Fonseca et al, 2015), with a floristic and structural complexity in contrast to the usual open formations (Rull and Montoya, 2014). Veredas are hygrophilous communities associated with hydromorphic or peat soil in headwater areas, where there are high water table (Guimarães et al, 2002;Ribeiro and Walter, 2008).…”

“…The veredas have a great environmental importance, especially in the northern region of Minas Gerais, which has a semiarid climate with marked seasonality and drought period of approximately eight months, or more (Neves, 2011). In the dry season, the veredas may represent the only sources of water, food and shelter for the associated species and the humans who inhabit these surroundings (Neves, 2011;Silva and Maillard, 2011;Resende et al, 2013). This happens in detriment of the fact that veredas act as great reservoirs: peat soil stocks the water which is released over time, making the rivers and streams downstream become perennial, mitigating the ef-fects of flooding and minimizing erosion (Moss, 2012).…”

“…In Brazil, several authors characterize the veredas as a savanna formation (Ribeiro and Walter, 2008), a mostly grassy field, where the forest cover ranges from 5-10% of the territory (Meirelles et al, 2002;Resende et al, 2013). The Brazilian Forest Code defines veredas as a "savanna vegetation type found in hydromorphic soils, with palm tree Mauritia flexuosa without forming canopy, among clusters of shrub and herbaceous species" (Brasil, 2012).…”

Regeneração natural, relações ambientais e invasão biológica em duas veredas do Triângulo Mineiro

“…The edge areas can show significant changes in their floristic composition, according to the characteristics and disturbance levels of the surrounding areas [12]. Moreover, direct alterations in these environments can lead to species diversity reduction and also facilitate biological invasion processes [7].…”