Resilience assessment on Phillyrea angustifolia L. maquis undergone to experimental fire through a big-leaf modelling approach

Abstract

In the Mediterranean area, plant response to summer constraints can be directly or indirectly affected by extensive fires, which have acted as modelling force for the actual Mediterranean habitat. The aim of this study is to evaluate the rate at which a Phillyrea angustifolia stand approaches to steady state after a prescribed fire, by calculation of the speed of return to re-constitution of the total standing biomass through the analysis of both physiological and structural parameters. Gas exchange and growth rates of the unburned and burned stands have been estimated by a deterministic model based on the big-leaf approach applied over a relatively short period of time. The model has been able to well simulate the gas exchange rates both for unburned and burned P. angustifolia stands. Further, resilience has been calculated by the slope of growth rate for each year of simulation. Burned stand showed higher physiological performance than unburned stand accordingly to measured data, and as a consequence it showed a high resilience, which allow to reconstitute the canopy structure in three years from the fire. At this regard, the simulated leaf area index had a tendency to reach values similar to those modelled for unburned stand. The model presented here may be useful to the decision makers for the setting up of plant reconstitution plans after a fire.