Estrutura da vegetação caducifólia espinhosa (caatinga) de uma área do sertão central de Pernambuco

Abstract

-(Vegetation structure of the thorny deciduous woodland (Caatinga) in an area of central sertão of Pernambuco). Vegetation structure of a "Caatinga" sensu stricto (thorny deciduous woodland) was studied in a lowland area at the municipalities of Floresta and Betânia, State of Pernambuco, Brazil. Height and perimeter of all woody plants to be found in 1 hectare were censured when stem perimeter at soil level was ≥ 3 cm and the height ≥ 1 m. A total of 3,140 individuals belonging to 28 plant species were registered with a basal area of 18.5 m 2 . In general, results from surveys at lowlands on plain areas presented smaller individual stem diameters than those located near streams or mountain range sites. Physiognomic differences in the caatinga sensu stricto on lowlands are related to differences on the density of plants with greater diameters. The diameter distribution of Caesalpinia gardneriana Benth. (Caesalpiniaceae) and Croton rhamnifolioides Pax & K. Hoffm. (Euphorbiaceae), the two most important tree species, indicate that these plant populations may be regenerating from former disturbance. Key words: "Sertaneja" depression, structure, woody plants RESUMO -(Estrutura da vegetação caducifólia espinhosa (Caatinga) de uma área do sertão central de Pernambuco). Foi realizada a descrição da estrutura da vegetação de caatinga sensu stricto do pediplano da depressão sertaneja situada entre os municípios de Floresta e Betânia, Pernambuco. Foram amostrados todos os indivíduos vivos com diâmetro do caule ao nível do solo ≥ 3 cm e altura total ≥ 1 m presentes em um hectare. Foram registradas 28 espécies, um total de 3.140 plantas com área basal total de 18,5 m 2 . Em geral, os levantamentos da depressão sertaneja, situados em áreas do pediplano, apresentam menores diâmetros que aqueles situados em áreas próximas a riachos ou serras. É possível concluir que as diferenças fisionômicas na caatinga sensu stricto da depressão ocorrem na função da densidade das plantas com maiores diâmetros. As distribuições diamétricas de Caesalpinia gardneriana Benth. (Caesalpiniaceae) e Croton rhamnifolioides Pax & K. Hoffm. (Euphorbiaceae), espécies de maior valor de importância, indicam populações em regeneração. Palavras-chave: depressão sertaneja, estrutura, plantas lenhosas

Rainfall patterns and the contribution of litter in the caatinga dry tropical forest

“…Although the absolute numbers show different values, the density of individuals in the two areas may be considered as similar, since the area calculated by Rodal et al (2008) was five times greater than the area of this study, and the vegetation of both studies was the same.…”

“…In the floristic survey 562 live individuals were identified in 20 plots of 100 m 2 each, while Rodal et al (2008) found 3,140 individuals in 100 plots of 100 m 2 each, in an area of 20 years preservation. Although the absolute numbers show different values, the density of individuals in the two areas may be considered as similar, since the area calculated by Rodal et al (2008) was five times greater than the area of this study, and the vegetation of both studies was the same.…”

“…The recorded individuals were grouped into 25 species (Table 3) similar to the quantitative floristic surveys of ligneous plants in areas of caatinga performed by Rodal et al (2008) and Santana and Souto (2006). These authors identified a total of 28 and 22 species respectively, with different species of caatinga-like plants among those dominant in their surveys.…”

Patterns of species richness and abundance among cactus communities receiving different rainfall levels in the semiarid region of Brazil

“…Th roughout most of its extent the annual rainfall is equal to or less than 1000 mm (AESA 2014). Furthermore, this precipitation is heterogeneously distributed as a result of two large moisture gradients, one in the north-south direction determined by decreasing precipitation, and the other in the east-west direction due to the eff ect of increasing continentality (Rodal et al 2008). Th e most common soil of the region is of crystalline origin, but areas of sedimentary soil are also present (Moro et al 2015;Moro et al 2016).…”

Florística e fitossociologia de espécies arbóreas e arbustivas em uma área de Caatinga em Arcoverde, PE, Brasil

“…Nos últimos anos, diversos trabalhos fitossociológicos e florísticos foram realizados em áreas de caatinga (LEMOS; RODAL, 2002;PEREIRA et al, 2002;ALCOFORADO-FILHO et al, 2003;MARACAJÁ et al, 2003;CESTARO;SOARES, 2004;ANDRADE et al, 2005;LACERDA et al, 2005, PEGADO et al, 2006QUEIROZ et al, 2006;SANTANA;SOUTO, 2006;FABRICANTE;ANDRADE, 2007;LACERDA et al, 2007;PINHEIRO;ALVES, 2007;PESSOA et al, 2008;RODAL et al, 2008a;RODAL et al, 2008b;SANTOS et al, 2008;RAMALHO et al, 2009;SOUZA;RODAL, 2010. ), tendo fornecido informações sobre florística e estrutura da vegetação de caatinga.…”