Differential productivity, phenology and NDVI in preserved subtropical forests of Northern Argentina: the importance of an endangered tree species for the functioning of a forest ecosystem

CAMPANELLO PAULA I.; MONTTI LÍA; CRISTIANO PIEDAD M.; GOLDSTEIN GUILLERMO

Bonito

Congreso; The 49th Annual Meeting of the Association for Tropical Biology and Conservation (ATBC); 2012

Aspidosperma polyneuron is an emergent evergreen tree in the semideciduous Atlantic Forest. Due to its high commercial value the abundance of this species has declined dramatically in the last century, while its effective distributional range has been reduced by changes in land use with the conversion of forests into agricultural land. Selective logging of A. polyneuron and other commercial species has changed light dynamics generating environmental conditions that favor the growth of fast growing native plants (e.g., bamboos and lianas), which become invasive after selective logging and inhibit tree regeneration. We measured tree basal area and the percentage solar radiation reaching the understory in forest areas dominated by A. polyneuron and in areas where this species is absent as a consequence of past logging activities. Through satellite image analysis (Landsat ETM+) we determined differences in NDVI among A. polyneuron dominated stands and surrounded native forests throughout the year. Most canopy trees in this forest ecosystem are deciduous but this evergreen species is able to change micro environmental conditions reducing solar radiation in the understory to very low values and potentially drive water, nutrient and carbon cycling as account for more than 60% of the above ground tree biomass in preserved forests. We propose that differences in NDVI due to phenology and seasonality could be used for mapping the distribution of forest stands dominated by this endangered species in NE Argentina.