Revista Chilena de Historia Natural 80 (1): 43-53, 2007
RESEARCH ARTICLE
Aboveground biomass in Prosopis pallida (Humb. and Bonpl. ex Willd.) H. B. K.
ecosystems using Landsat 7 ETM+ images
The significance of field work in remote sensing studies when applied to large areas has
often been underestimated. The combination of specific forest inventories for the estimation of aboveground biomass in large dry
tropical forest areas with remote sensor data has scarcely been explored to date. In this work, a systematic, stratified forest inventory
involving 100 x 100 m square plots in an area of Peruvian Prosopis pallida dry forest, roughly one million
hectares in size in the Piura province (Peru) has been compiled. The inventory encompassed the principal silvicultural variables
defining the ecosystem studied, which were used in allometric equations for the different species, genera and plant associations in the
area in order to estimate the amount of aboveground biomass present in each plot. Field data were related to a Landsat 7 ETM+ image
by using six different vegetation indices derived from an image mosaic for the area. Two regression equations (relating the amount of
aboveground phytomass to the different vegetation indices) provided reasonably acceptable phytomass predictions for the type of
ecosystem concerned (R<sup>2</sup> between 0.72 and 0.52).
Key words:
Prosopis
pallida, Landsat 7 ETM+, vegetation indices, biomass estimation
