Análise de tendência da mudança na cobertura vegetal na mesorregião da Borborema paraibana.

Abstract

Variations in vegetation cover in a given region occur for the most numerous reasons, including deforestation, the implementation of agricultural systems, as well as more persistent climatic variations such as the great droughts that occur in the semiarid northeast of Brazil. The objective of this work was to evaluate the spatiotemporal behavior of the caatinga biome in the Mesoregion of Borborema Paraibana (MBP) in addition to the transitions to other uses and/or covers resulting from this variation. For this, the cluster analysis technique (CA) and the MannKendall tests and the Sen method were used to identify the trend and quantify it, in addition to the Pettitt test to characterize the homogeneity of the variable for the period of 1985 to 2019. The results showed that the region is not homogeneous in terms of vegetation cover, with two areas with notorious vegetation losses (Cariri Ocidental and Seridó Oriental) that present very characteristic economic systems, in addition to what the analysis of the transition of native vegetation showed that the increase in agricultural systems, especially areas destined for pasture, are exerting the greatest pressure on this biome. The cluster analysis made it possible to divide the region into 5 groups, with groups 1 and 5 showing a statistically significant trend of vegetation recovery, groups 3 and 4 showed a positive trend of vegetation reduction and group 2 showed a trend of loss of vegetation. vegetation, but without statistical significance, all groups presented a break in the homogeneity of the series, demonstrating a significant change in vegetation cover values over the period studied.