Estudo espaço temporal de áreas susceptíveis à desertificação no semiárido brasileiro

Abstract

Desertification is a serious environmental problem of land degradation, which af fects many countries around the world, but it is in the arid, semi arid and sub humid regions of developing countries that this phenomenon has been causing real d i sa s ters due to the natural fragility, anthropic actions and climate change. In the state of P ernambuco, desertification is installed, in the so called desertification nucleus of Cabrobó, however, 136 municipalities are part of areas susceptible to deserti f ic a tion. The basin of the Moxotó river, is part of the San Francisco sub regio n and is totall y inserted in areas susceptible to desertification. This research had as its focus a study of the temporal space of areas susceptible to desertification, in the M o xo t ó river basin. A georeferenced database was created with images of LANDSAT 5 TM and LANDSA T 8 OLI satellites. In SPRING, the technique of Linear Spectral Mixture MLME was applied. The Spatial Language of Algebraic Geoprocessing LEGAL was used in th e c r ossing of maps and obtaining indices of vegetation IVDN and IVAS. The spatialisation of the surface temperatur e (Ts) and the finalization of the maps were performed in the QGIS 2.18 software. The results showed that the Moxot ó river basin presents appro x im a tely 32% of vegetated areas, conserved during the 21 years of study, 28% of degraded areas, 21% of areas tha t were recovere d, 9% of areas with potential to desertification, and 10 % of water bodies, clouds and shadows during the study period. The most a ff e cted municipalities in the Moxotó river basin are located in the State of Pernambuco and include Ibimirim, I najá and Cust ó d ia In the State of Alagoas, the affected municipalities are Mata Grande, Pariconha and Delmiro Gouveia. In this sense, the datab a se provides information that corroborates the study of desertification in the Brazilian semi arid region. In th e context of en vironmental management, the results may contribute to the discussion on sustainable management practices in degraded areas and to su p port decision making regarding the implementation of actions and programs that can support territorial devel opment with sus tainability.