Análise quali-quantitativa da vegetação arbustivo-arbórea da caatinga, em Teixeira-PB.

Abstract

The vegetation of the semi-arid northeastern Brazil is understood by caatinga, which is largely determined by climate and topography. The area of the municipality of Teixeira-PB has a land cover of hyperxerophilous shrub-arboreal caatinga which is different in size and density from those found in the Sertaneja Depression, driven by increased humidity, which is very much altered due to the cultivation of sisal, as well as other regional products. The work aims to qualify and quantify the forest remaining in the municipality of Teixeira-PB, through GIS techniques and forest inventory. Teixeira-PB is located in the Paraíba backlands mesoregion and in the Serra do Teixeira microregion, with an area of 182 km2. In order to map native vegetation were used satellite images, related to the month of November 2008. Forest inventory was carried out with the use of sampling plots, systematically selected in a total of 40 samples with dimensions of 20 x 20 m. Each tree was identified by its common and scientific names. We measured the CAP and the height (H). Currently, the vegetation cover in the municipality of Teixeira-PB corresponds to an area of 11,760.1 ha, representing 64.5% of the total area of the municipality. The arboreal vegetation was sampled from 4911 individuals belonging to 46 species and 24 families, corresponding to 3069 individuals per hectare. The species which contributed with the larger number of individuals was the Croton sonderianus. The species with highest importance value (IV) were: Croton sonderianus, Mimosa tenuiflora, Piptadenia stipulacea, Manihot glaziovii, Mimosa ophtalmocentra, Myracrodruon urundeuva, Anadenanthera colubrina, Caesalpinia pyramidalis, Bauhinia cheilantha and Senna spectabilis. The basal area was estimated at 7.75 m2.ha-1. The total volume was estimated at 44.89 m3.ha-1. The best preserved areas are in mountainous regions, which are difficult to access. The families that stood out were Euphorbiaceae, Mimosaceae and Caesalpinaceae. Croton sonderianus was the species with the greatest number of individuals, the highest level of importance and greater basal area. Most species showed an aggregated distribution.