Temporal analysis of desertification vulnerability in Northeast Brazil using Google Earth Engine

Abstract

AbstractIntensive agricultural production has negative environmental impacts, increasing predisposition to desertification in areas with inadequate soil management. To evaluate the effects of agriculture, we aimed to perform a temporal analysis and analyze the development of desertification in Northeast Brazil. Initially, the region was separated into four climatic zones, grouping the locations with similar characteristics of air temperature and rainfall. In the analyses, images of the northeast region acquired from the Landsat 5 (1989, 1999, and 2009) and Landsat 8 (2019) satellites were processed using the Google Earth Engine platform. The periods were separated into dry and rainy periods, according to the climatic zones. The evaluation of vegetation index, characterization of the remaining vegetation cover, landscape pattern, and meteorological conditions were performed, respectively, through the Normalized Difference Vegetation Index, Modified Soil‐Adjusted Vegetation Index, and albedo of the terrestrial surface. The desertification index showed an increase in susceptible areas when comparing the interval from 1989 to 2019. In general, our results showed that there is less predisposition for desertification to occur during the rainy season. Also, when the results of our study were compared to official data released by the National Program of Action to Combat Desertification and Mitigate the Effects of Drought, there was disagreement regarding the classification of areas.