Geoprocessing techniques applied for temporal analysis of the microclimate in the Pequia stream watershed, Maranhao

Abstract

The suppression of vegetation, the increase in human activities without the necessary mitigation measures and the climate change that has occurred over the years have been important indicators of environmental degradation, directly affecting the quality of life and health of the population. In view of technological advances and the improvement of geoprocessing techniques, evaluating these changes is becoming an important guiding instrument for public policies, mainly due to the possibility of temporal analysis through Remote Sensing (RS). In this sense, the present study analyzed, through LANDSAT-5 and 8 satellite images in two distinct periods - 1984 and 2020 -, the relationship and spatiotemporal variation of the Surface Temperature (TST) with the Normalized Difference Vegetation Index (NDVI) in the hydrographic basin of the Pequi & aacute; stream, which has a territorial extension of approximately 1000 km' and is inserted in the municipalities of A & ccedil;ail & acirc;ndia, S & atilde;o Francisco do Brej & atilde;o and Jo & atilde;o Lisboa, state of Maranh & atilde;o (MA), and it was verified that the suppression of vegetation, driven by 36 years of intense anthropogenic activities and without adequate monitoring, altered the dynamics of the forest in several points of the basin, causing an average increase of TST of 4 o C, and it is possible to conclude that there is a need for forest recomposition in strategic points of the basin, in order to mitigate such impacts. Finally, it is believed that the results presented here can be used as subsidies to public managers in the state of MA, in order to use them to monitor the temporal suppression of vegetation and climate change.