Análise do componente arbustivo-arbóreo regenerante em área de mata ciliar degradada no Cariri Paraibano.

Abstract

The Caatinga is the third most degraded biome in Brazil. In this region, water availability causes riparian forests to be the most affected environments with the removal of vegetation for agricultural activities. Natural regeneration consists of the interaction of natural processes that result in the recovery of the forest ecosystem and its study allows to make projections on the future development of the forest. The objective of this work was to evaluate the regenerating young people bank in a degraded river ecosystem in the municipality of Livramento, semi-arid region of Paraíba. Field research was carried out in an area in the municipality of Livramento/PB, located in the Western Cariri Microregion. The activities were supported by exploratory excursions initially carried out at several points in the of municipality, in addition to the analysis of maps and vegetation maps. The monitoring of the regenerating shrub-arboreal component was performed monthly from July to November/2018. The bank of young individuals was analyzed by the implantation of 50 plots of 1 X 1 m. All the young woody individuals present in these plots, with height < 1 m and DNS < 3 cm, were labeled, numbered and identified by scientific name, measuring the total height values with a graduated ruler and for diameter was used a Digital caliper. In the structural analysis of vegetation the following parameters were used: frequency, density and height classes and natural regeneration diameter. In the set of 50 plots sampled in the Riacho Verde, 19 individuals were recorded and identified in the inventory, distributed in three families, six species, six genera and one indeterminate. The predominant component was arboreal. The families with the highest number of species were Euphorbiaceae with three, followed by Fabaceae with two. Of the 50 plots sampled, the species that obtained the highest frequency was Mimosa tenuiflora (11 plots). In relation to the height and diameter classes, a greater distribution of individuals in the lower value classes was observed. For the height, more than 40% of the individuals concentrated in the lowest class of 0.01 to 0.25 m and the diameter followed the same pattern, with the largest number of individuals in the first class (1.01 to 3.00 cm), 45% of the total number of registered individuals. it was observed that in plot 42 the largest number of individuals (five), plots 21, 43 and 45 (three each) occurred, being the smallest number (one) in plot 49 and in the others there were no individuals. In general, the study area presented a floristic composition with a reduced number of species when compared to other riverine ecosystems, which demonstrates the high degree of anthropization of the area, which increasingly accentuates the level of degradation. Therefore, the information generated in the work is defined as important contributions to the strategies of restoration of degraded environments.