Biomass allocation of the invasive tree Acacia auriculiformis and refoliation following hurricane-force winds1

Abstract

Allometric equations and biomass allocation were determined for the aboveground wood, branch, twig, and leaf components of the invasive tree Acacia auriculiformis in south Florida prior to and after a major hurricane event. A destructive harvest was used and plant partitioned biomass was quantified for 35 trees prior to landfall of hurricane Wilma (October 2005), followed by an assessment of 29 hurricane impacted trees (representing all ontogeny classes) three months later. Allometric equations were developed to estimate plant partitioned biomass using diameter at base and diameter at breast height as predictors of biomass components, leaf area, leaf area ratio, and leaf weight ratio. Diameter at base was the best predictor of biomass allocation in all regression analyses. Hurricane force winds did not alter biomass of major woody components; however significant losses were observed in twig biomass and all measured leaf parameters. The replacement of damaged foliage resulted in overcompensation of leaf area and leaf area ratio. Similarly, leaf biomass, and leaf weight ratio also increased following the hurricane, but levels were lower than pre-hurricane observations. This research facilitates the prediction of A. auriculiformis biomass using non destructive sampling protocols while quantifying its resiliency and compensatory abilities following hurricane disturbance.