a) and b) Spectral band evolution in pseudo-invariant (OLI, olive) and variant (wheat) features; c) and d) NDVI evolution in pseudo-invariant features (CIT, citrus; OLI, olives, and POP, poplar groves); and d) winter wheat and corn as representative cropping systems that have variant vegetative features.

<p>The abscissa is the remote image timing (V1- early April to V7 - early October, interval of approximately one month; data are presented as the means, and vertical bars represent the standard deviation (s. d.) of six parcels of approximately 3 ha each).