Biomass hyperdynamics as a key modulator of forest self-maintenance in a dystrophic soil in the amazonia-cerrado transition

Abstract

In this study, we looked for differences in litterfall between cerradão (forest type) and typical cerrado (savanna type) and sought to relate the dynamics of vegetation with the biomass input and the possible positive effects of this process. We collected litter and tested the hypothesis that the cerradão, due to its greater biomass and higher dynamics, presents a higher litterfall and therefore a higher intensity of cycling and is more likely to self-maintain in poor nutrient soils. The total litterfall input was higher in cerradão (7.71 in 2011, 9.76 in 2012 and 8.70 Mg.ha-1.year-1 in 2013) compared to typical cerrado (3.84, 4.10 and 4.23 Mg.ha-1.year-1, respectively), confirming our hypothesis. These results demonstrated that the net primary production is distinct among the phytophysiognomies, with greater intensity in cerradão. This biomass hyperdynamics condition can promote nutrient cycling and its maintenance in dystrophic soils.