IFEVA   02662
INSTITUTO DE INVESTIGACIONES FISIOLOGICAS Y ECOLOGICAS VINCULADAS A LA AGRICULTURA
Unidad Ejecutora - UE
artículos
Título:
Caracterización funcional de la vegetación del Uruguay mediante el uso de sensores remotos
Autor/es:
BAEZA, S., PARUELO, J.M. Y ALTESOR
Revista:
INTERCIENCIA
Referencias:
Año: 2006 p. 382 - 387
ISSN:
0378-1844
Resumen:
SUMMARY
The Normalized Difference Vegetation Index (NDVI) is a
spectral index derived from sensors on board of satellites that
shows a positive and lineal relationship with the proportion of
photosynthetic active radiation absorbed by the canopy. The
NDVI is a good estimator of primary productivity, an important
ecosystem attribute. In this article the ecosystems of Uruguay
were characterized on the basis of three attributes derived of
the seasonal curve of the NDVI using 20 years of images of
the satellites NOAA/AVHRR (1981-2000). The annual integral
of the NDVI (IVN-I), an estimate of the aboveground net pri-mary
production; the month of maximal NDVI (IVN-MDM);
and the relative range of NDVI (IVN-RREL), attributes that
account for the seasonal character of the primary production
and reflect critical aspects of the ecosystem functioning, were
the calculated attributes. Based on their behavior, each portion
of the Uruguayan territory was classified as an ecosystem
functional type (TFE), combining supervised and unsupervised
classification methods, together with hierarchical analysis. Six
TFE that differed significantly among them were identified. The
spatial variation of the three attributes was associated mainly
to the geomorphologic structure and land use patterns, and not
to climatic variables.