Estrutura e dinâmica de uma população de Caesalpinia echinata Lam. (pau-brasil) no litoral norte da Paraíba : uma perspectiva para conservação da espécie

AUTOR(ES)
DATA DE PUBLICAÇÃO

2006

RESUMO

The Pau-Brasil (Caesalpinia echinata Lam.) is a native species of Mata Atlântica, explored extensively since the discovery of Brazil. Nowadays almost disappeared, as a result of the coast forest devastation, being part of the official list of brazilian flora species threatened with extinction. This work had the objective of studying the dynamic and the structural behavior of the native populations of Pau-Brasil, focusing on biodiversity maintenance and conservation of this species in its natural environment. The work was developed in the ecological station of Pau-Brasil, located at the north littoral of Paraíba State, in Mamanguape municipality, coordinates (6 36 16 S, 35 07 45 W). The characterization of the stations vegetation was made using the multiple plots method, randomly allotting 100 plots of 10 x 10 meters. In each plot was measured the diameter at breast height (DBH) and the total height of all arboreous individuals, including the Pau-Brasil. The collected were used to calculate the parameters of abundance, frequency, dominance, significant and covering value, as well as the Shannon diversity index and the equability (J). Exclusively for the Pau-Brasil the flowering and fruiting pattern was observed, an also the natural regeneration, mortality and recruitment of the species, through 20 sub plots of 1 x 1 meter, which, after six months and one year, was re-censored and re-measured. According to the results of the floristic and phytosociology composition, the richest family in number of genera and species was the Leguminosae; the predominant and the highest importance value and covering species was the Caesalpinia echinata. The Shannon diversity index was 3,14, and the equability (J) was 0,83. The diameters frequency distribution of the Pau-Brasil individuals indicated a tendency to normal curve (bell shaped) and the q index demonstrated an uneven distribution of the population, due to the species mortality steadily overcoming the recruitment. The flowering and fruiting pattern observations revealed a correlation between the period of less rain concentration the presence of that phenofases. The dispersion process of the species occurred by explosive dehiscence. However, it seems not being efficient for the natural repopulation of the species, with the majority of seedlings concentrated in just on place of the forest. The species indicated a low development of its plants and a mortality index of 81,14%, after one year of observation. To guarantee the preservation of the species in the Ecological Station of Pau-Brasil, it is recommendable the adoption conservationist actions like: the delimitation a deadening zone, to integrally protect the station but continuous vigilance, the promotion and icentive of scientific researches and to support the development of maintainable projects involving the community that lives around the station, giving that community a means of income, reducing the human pressure on the forest fragment

ASSUNTO(S)

mata atlântica biodiversidade pau-brasil ecofisiologia vegetal mata atlântica preservation biodiversity preservação pau-brasil

ACESSO AO ARTIGO

Documentos Relacionados