TITLE:
Evaluation of Desertification Processes in Seridó Region (NE Brazil)
AUTHORS:
Reinaldo Antonio Petta, Leila Vespoli de Carvalho, Stefan Erasmi, Charles Jones
KEYWORDS:
Desertification; Caatinga; MODIS; Landsat; NDVI; Seridó; Brazil
JOURNAL NAME:
International Journal of Geosciences,
Vol.4 No.5B,
October
11,
2013
ABSTRACT: This paper outlines procedures to analyze the
desertification processes in the semi-arid Seridó Region (NE Brazil). Using the
Geosystem theory, the detection of desertification areas was based on
environmental indices, digital image processing in multispectral analysis and
Geographic Information System (GIS).The first step was to treat
the rainfall data and NDVI satellite Modis, aiming at identifying areas which
do not present vegetation cover, even during the rainy seasons.The second
step was to work on a regional scale using Landsat ETM + images (2000-2005) and
data collected in the field, as the evaluations of exposed surfaces, that
together with MDT/SRTM-NASA and thematic maps, allowed to classify the
altitude and slope of the relief, soils type, different morphologies and
geology, and correlate them with the areas susceptible to desertification
process. The integration of the georeferenced data, related to these
indicators, allowed the identification of five different levels of
susceptibility to desertification (very high, high, moderate, low and very
low), and the geographic domain of each class. Based on the analysis of the
dynamics of the vegetation cover, we can establish that the main results refer
that there is a decrease of the biomass at the region, associated with the
dense caatinga vegetation areas, but more important, with the scrub and
degraded areas.