ABSTRACT
The objective of this work was to analyze and compare spectral indexes in eucalyptus plantations and correlate them with precipitation data for the period from 2003 to 2012, in order to assess whether climate change has an influence on vegetation phenology. The methodology entailed obtaining the mean spectral indexes (NDVI, EVI and GPP) of MODIS images and elaborating the temporal profiles of the eucalyptus vegetation, for both cloned seedlings and those grown from seeds. These profiles were correlated with TRMM precipitation data. The results showed NDVI values higher than the EVI, although a clearly de fined seasonality was not present, whereas the GPP demonstrated a well-defined seasonal behavior in all of the years. The correlation between the spectral indices and the precipitation had representative results for some years, including El Niño and La Niña periods. It was concluded that MODIS products allow the evaluation of phenological cycles in eucalyptus plantations, principally for the planting and cutting phases.
Keywords: Spectral indices; MODIS sensor; Stands of eucalyptus