Análise multitemporal das alterações na cobertura do solo na bacia do rio Taperoá, semiárido, no período de 1986 a 2015.

Abstract

Remote sensing allows monitoring of land cover from vegetation indexes. Analyses of longterm trends in land´s cover are generally performed with high temporal resolution´s and low spatial resolution´s sensors. However, in heterogeneous regions such as the Brazilian Semi-arid Region, understanding the dynamics of land cover at local scales is very important, particularly in relation to the scale of human action. The medium spatial resolution allows identifying alterations in the scale of small rural properties and it is compatible with human action scale in Caatinga´s biome. The approach applied to this work makes possible to measure the period in which such changes occurred. In this work, the Mann-Kendall trend´s test was used to evaluate the performance or the capacity of the biophysical indicators EVI (Enhanced Vegetation Index); and surface Albedo to identify changes in soil cover. It was possible, as well, to identify, through estimates of temporal trends, areas and periods with possible variations in soil cover in 5-year temporal groupings. In total, 162 LANDSAT images were used, in the period from 1986 to 2015, focusing on Taperoá´s river basin, in the State of Paraíba, Brazilian semiarid region. Although EVI is the biophysical indicator most widely used to assess changes in soil cover, surface Albedo has been more sensitive in indicating probable areas altered as well as in indicating in which period such a change occurred. The evaluations provide tools for the development of remote monitoring and ecosystem management systems and can be used to identify regions of priority for interventions and observations that are more detailed.