Mapping the Preservation of Springs Using the SICAR® Database and MAPBIOMAS® Whit Modeling in QGIS®

Abstract

This study aimed to evaluate the degree of preservation and map spring areas in the state of Paraíba using geoprocessing techniques. Raster data on vegetation cover were obtained from Mapbiomas^® and were geospatialized using the QGIS^® 3.4.2 software. Shape data on the Environmental Protection Area, which includes springs and water sources in the study region, were obtained from the Rural Environmental Registry System and a 50-meter vector line was generated around the springs using the buffer tool. In the modeling for the preparation of the map of degree of preservation, the map was cropped using the difference tool of the geoprocessing module and then reclassified using the GRASS^® 8.4.1 tool. In the statistical treatment, the normality test was performed using the RCoreTeam^© plugin and the density curve was created. To verify whether the samples came from a certain probability distribution, the Lilliefors nonparametric hypothesis test was used. The geoprocessing techniques and methodology used were efficient and fast. The data used were accurate and totaled 1,392 springs, mostly located in steeper areas such as the Brejo Region in the Mamanguape River basin. The Mapbiomas^® data were accurate and important for determining the degree of preservation. Regarding the spatial distribution of the classification of the springs, it was observed that there is a close relationship between land use. The mapped springs presented a degree of Preservation in 54.82% of their total area, followed by Moderately Degraded in 13.93%. The statistical test showed normality in the distribution of the springs and their degree of preservation, as well as in their distribution density.