We present a classification of Patagonian ecosystems based on functional attributes derived from the seasonal curves of Normalized Difference Vegetation Index (NDVI), calculated from spectral data provided by the NOAA/AVHRR satellites. The attributes used were the annual integral, the relative range of NDVI, and the date of maximum NOW. These attributes capture critical aspects of the seasonal dynamics of carbon gains and allow for a good description of the spatial heterogeneity of ecosystem function in temperate areas. Our analysis defined 12 biozones that capture current ecosystem functioning. The units defined showed a good agreement with previously defined phytogeographical provinces. Mapping biozones based on attributes derived from satellite data does not require assumptions on the relationship between vegetation units and environmental features. This reduces the errors associated to the lack of correlation between the vegetation and environmental features.