Disturbance intensity and seasonality affect the resprouting ability of the neotropical dry-forest tree Acacia pennatula : do resources stored below-ground matter?
2011; Cambridge University Press; Volume: 27; Issue: 5 Linguagem: Inglês
10.1017/s0266467411000290
ISSN1469-7831
AutoresGuille Peguero, Josep María Espelta,
Tópico(s)Fire effects on ecosystems
ResumoAbstract: Many plant species in tropical dry forests partly base their ability to persist after disturbance on resprouting. Yet little is known if this ability can be affected by the intensity and seasonality of disturbance and whether the amount of resources (starch, N, P) stored in the taproot may constrain this response. We investigated resprouting after experimental clipping or burning, applied before or after the dry season and repeatedly in Acacia pennatula individuals in wooded rangelands of North-West Nicaragua. Each treatment was applied to 12 trees and replicated in six plots. One year after the onset of the experiment, survival and biomass recovery were significantly lower in burned than in clipped individuals (78% ± 4% and 75.3 ± 8.0 g vs. 94% ± 2% and 79.1 ± 6.8 g; mean ± SE). Whatever the disturbance applied, trees disturbed after the dry season significantly showed the lowest survival, growth and concentration of N and P. These results suggest that resprouting in dry tropical species may be constrained by intense disturbances (e.g. burning) but especially if they occur towards the end of the dry season. This phenological constraint could be due to the reduced availability of N and P as this dry season progresses.
Referência(s)