Fitossociologia de espécies arbóreas e arbustivas em uma área de Caatinga com diferentes estágios de antropização, na fazenda Jurema, no município de Pombal - PB.

Abstract

The indiscriminate use of wood, firewood and charcoal; intensive grazing of animals; the fire; the irrational use and management of land by agriculture; mining; besides the low income and cultural level of the population, have been identified as determinants of the environmental imbalance, inducing processes of desertification in the Brazilian semiarid region. The objective of this work was to perform a survey of the phytosociological composition in a preserved area and also in an anthropic area at the Jurema farm, Pombal - PB, in order to contribute to the construction of a knowledge about the existing vegetation. It was performed with 4 plots of 10 x 20 in each area that was surveyed. And they showed results as of Mimosa Hostilis that presented the absolute frequency in the two areas. Therefore, it is verified that the most abundant taxa in area I were: Caesalpinia pyramidalis, and Mimosa hostilis. Being responsible for 38.46% and 28.37% of the total sampled. In the area II Mimosa tenuiflora and Caesalpinia pyramidalis were the species of greatest abundance, being this one responsible for 93.75% and 6.25% of the total sampled individuals respectively. Regarding the relative dominance, Caesalpinia pyramidalis and Mimosa hostilis were predominant species in relation to the others, even though the latter two were inferior in number of individuals compared to the species Mimosa tenuiflora and Combretum leprosum. Regarding the relative frequency of the species, it was verified that Caesalpinia pyramidalis, and Mimosa hostilis. They presented value of 64% and 22% respectively for area! it can be concluded that: Man's actions directly influence the structure and diversity of the species; The species that are most important in the study areas under the phytosociological aspects were Caesalpinia pyramidalis and Mimosa hostilis in area I; The species that are most important in the study areas under the phytosociological aspects was Mimosa tenuiflora in area II; The diversity of species is considered very low when compared to other forest fragments of caatinga already studied.