Relationship between the global vegetation index and water conditions in Rio Grande do Sul

Abstract

The global vegetation index (GVI) is nowadays the best available index to detect changes in vegetation quantity and conditions at regional and global scales. This is determined by the global daily coverage of the Earth (NOAA satellite), availability of appropriate spectral bands to monitor vegetation (AVHRR sensor) and the small number of generated data. The main objectives of this research were to evaluate the capability of GVI monitoring natural vegetation and crop status in the climatic conditions of the state of Rio Grande do Sul, Brazil, and to study the relationship between GVI and water conditions. Temporal series of meteorological elements and GVI images were utilized in weekly scales, from September 1982 to May 1986 period. The temporal evolution of GVI followed the standard growth and development spring-summer crops curve, allowing to use this index in crop monitoring in the west portion of the state of Rio Grande do Sul.