Diversidade de herbáceas em microhabitats rochoso, plano e ciliar em uma área de caatinga, Caruaru, PE, Brasil

Abstract

RESUMO -(Diversidade de herbáceas em microhabitats rochoso, plano e ciliar em uma área de caatinga, Caruaru, PE, Brasil). Objetivou-se avaliar a influência da heterogeneidade micro-espacial no aumento da fitodiversidade herbácea em uma área de caatinga de Caruaru, Pernambuco, Brasil. Microhabitats rochosos, planos e ciliares foram selecionados, e nesses foi realizado um levantamento qualiquantitativo das herbáceas ocorrentes em 35 parcelas de 1 m 2 , em cada microhabitat. Todas as ervas nas parcelas foram contadas, marcadas e identificadas, coletando-se também outras espécies herbáceas ocorrentes entre as parcelas. A riqueza taxonômica total de herbáceas foi mais elevada ao se considerar o conjunto dos microhabitats. A flora total foi de 62 espécies, 42 destas ocorrendo no microhabitat rochoso, 32 no plano e 39 no ciliar. O índice de similaridade florística de Jaccard entre os microhabitats variou de 42% (plano × ciliar) a 57% (rochoso × plano). Isoladamente, as riquezas de espécies nos microhabitats plano, rochoso e ciliar foram de 3,09; 3,88 e de 4,18 espécies (ln ind.)-1 e as diversidades, pelo índice de Shannon-Wiener, foram de 2,08; 2,09 e de 2,52 nats.ind.-1 , respectivamente. Malvaceae, Euphorbiaceae e Poaceae apresentaram maior número de espécies. A densidade total de herbáceas foi de 4.009 ind.105 m -2 , sendo 1.749 indivíduos do microhabitat rochoso, 1.020 do ciliar e 1.240 do plano. Cerca de 19% das espécies eram trepadeiras e foram consideradas como um grupo importante para conservação da biodiversidade local. Evidenciou-se a importância da inclusão das herbáceas dos diferentes microhabitats, para a determinação da riqueza florística da caatinga. Palavras-chave: riqueza de espécies, densidade de herbáceas, semi-árido, caatinga, microsítiosABSTRACT -(Diversity of herb plants in three microhabitats at a caatinga site: level area, rocky area and stream border area, Caruaru, PE, Brazil). The influence of the micro spatial heterogeneity in the diversity of herb plants was evaluated in a caatinga site at Caruaru, Pernambuco, Brazil. Three microhabitats were chosen: a flat area with a rocky yellow podzolic soil, a similar area with the same soil type but without rocks and an area at the border of a small intermittent stream but that is never covered by floods. In each microhabitat, 35 plots, 1m 2 each, were marked, at random, and all herb plants identified and counted. Plants were also collected and identified in the same microhabitats outside the plots. A total of 62 species were found in the three microsites, 32 in the flat area, 42 in the rocky area and 39 in the stream area. Similarity, using Jaccard index, ranged from 42% (flat x stream area) to 57% (flat and rocky area). . Malvaceae, Euphorbiaceae and Poaceae were the families with highest number of species. About 19% of the species were climbing plants and were considered an important group for local biodiversity conservation. The importance of the inclusion of the herb plants of the different microhabitats for the determination of the floristic rich...

Flowering plants of the Grota do Angico Natural Monument, Caatinga of Sergipe, Brazil

“…Similar numbers were found by Alcoforado-Filho et al (2003) and Araújo et al (2005) in other areas of the Caatinga. Epiphytes showed a low number, with only three species of Bromeliaceae.…”

“…Fabaceae presented the highest richness of herbaceous species per family (14: 11 in Faboideae and 3 in Caesalpiniodeae), followed by Asteraceae (10), Poaceae (9) and Malvaceae (8). These families were predominant in different habitats of Caatinga, such as rocky, flat and gallery microhabitats (Araújo et al 2005;Reis et al 2006), crystalline and sedimentary areas ), and caatinga s. str. (Costa et al 2009).…”

Inter-annual variations in the floristic and population structure of an herbaceous community of "caatinga" vegetation in Pernambuco, Brazil

“…The herbaceous flora of the "caatinga" vegetation, however, is less well know, although previous studies have demonstrated that it: 1) retains the greater part of the biodiversity of the "caatinga" biome , Araújo 2003; 2) is composed predominantly of terophytes plants, and is therefore most apparent during the rainy season (Pereira et al 1989, Araújo 2003, Reis 2004, Silva 2004; 3) influences the dynamics of the woody vegetation component (Araújo 1998); 4) contains habitat-specific species (Reis 2004, Araújo et al 2005b; 5) flowers and fruits most intensely during the raining season, like the woody vegetation (Pereira et al 1989, Reis 2004, Silva 2004, Feitoza 2004) and 6) has great value as pasture, or for apiculture (Carvalho & Marchini 1999, Sampaio et al 2002, Lorenzon et al 2003. It has been suggested that the herbaceous vegetation has an important role in maintaining the biodiversity of the woody component of the flora, as their roots help maintain the soil seedbank (Araújo 2003, Feitoza 2004.…”

Environmental characterization of sub-basin of the river Taperoá - Paraíba

“…Araújo et al (2005) afirmam que a umidade, principalmente no solo, tende a favorecer o desenvolvimento da vegetação com porte lenhoso, e característica arbórea e arbustivas.…”