Navegando por Assunto "Caatinga"

Agora exibindo 1 - 3 de 3

Acesso aberto (Open Access)
Análise biogeográfica da avifauna de uma área de transição cerrado-caatinga no Centro-Sul do Piauí, Brasil
(Universidade Federal do Pará, 2001-01-16) SANTOS, Marcos Pérsio Dantas; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
Acesso aberto (Open Access)
Padrões de distribuição e a conservação das aves passeriformes da caatinga
(Universidade Federal do Pará, 2004-05-10) SOUZA, Manuella Andrade de; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
The Caatinga is an exclusively Brazilian biome mainly located in the Northeast region. This ecosystem is little studied and is also one of the most threatened and altered by humans. The aim of this study was to determine the areas with highest richness of passeriforms, to identify how these species are distributed and how they use habitat resources. Moreover, we tested the efficiency of Conservation Units and Priority Areas proposed by PROBIO to protect endemic and threatened taxa. Most of the 273 taxa of passeriforms recorded for the Caatinga depend direct or indirectly upon forests to survive. A number of 37 taxa were registered as endemic for the region, of these 26 are dependent of forest. The areas of higher richness are directly related to habitat diversity. A total of 10 most important priority areas were identified for the conservation of endemic and threatened passerines. In addition to covering only a reduced area of the ecosystem, the conservation units do not fully represent the endemic and threatened taxa for the biome. Thus, an efficient system of conservation of the Caatinga shall consider the landscape diversity, especially for the conservation units forested areas and caatinga-like neighbouring vegetation.
Acesso aberto (Open Access)
Taxocenose de serpentes (Squamata: Serpentes) em uma área de transição cerrado-caatinga no município de Castelo do Piauí, Piauí, Brasil
(Universidade Federal do Pará, 2007-05) RODRIGUES, Francílio da Silva; PRUDENTE, Ana Lúcia da Costa; http://lattes.cnpq.br/1008924786363328
A survey of the snake fauna in a transition area between Cerrado and Caatinga in the municipal district of Castelo do Piauí was made. Six trips were accomplished between October, 2005 and July, 2006, in three vegetation types: Rocky Savanna, Open Savanna and secondary growth of Tipical Savanna, totalizing 120 days of field work. Three methods were used: Pitfall traps with drift fences, Time Constrained Search and Occasional Encounters. Eighteen species were registered. As expected for the South American formations, Colubridae presented the greatest species richness. The community is predominantly composed by Xenodontinae (11 species), following by Colubrinae (Mastigodryas bifossatus and Spilotes pullatus) and a single species of Dipsadinae (Leptodeira annulata), reflecting the community structure and the evolutionary pattern of the colubrids phylogenetic lineages. Thamnodynastes sp. (n = 7), Philodryas nattereri (n = 5) and Phimophis iglesiasi (n = 5) were the most abundant species in the studied area, different from others formations of snake communities in Brazil which are dominated by Viperidae. The richness estimators Chao 2 and Jack1 indicate that the community is composed by nearly 24 species. Time Constrained Search was the most effective method, although it is recommended the use of the three methods for a more complete snake survey. It was demonstrated the predominance of terrestrials, diurnals, oviparous snakes, which probably feeds on amphibians and lizards. The Principal Coordinates Analysis, cluster analysis, similarity indices and distribution patterns of the species between the biomes, shows that the studied area is more similar to open areas (Cerrado, Caatinga e Pantanal) that to forest formations, reforcing the idea that the snake community of Castelo do Piauí suffers direct faunistical influence from the Cerrado and Caatinga biomes. This data are congruent with those from flora studies, and point preferential association to Caatinga communities. The PCO and cluster analysis suggests that the hypothesis of mixed composition of Cerrado and Caatinga faunas, as pointed in other studies, is based on misinterpreted data.