Modelling cork oak production in Portugal.

Cork oak (Quercus suber L.) stands are managed in agro-silvo-pasture systems and their sustainability depends on balanced relations amongst their components. Actual changes in management, mainly due to increasing mechanization and the installation of new stands, have required the development of tools to generate scenarios for management options. The maintenance of a balanced sustainable land use that may cope with the variability of the Mediterranean climate is the main ecological output. The economical output is mainly related to cork production which feeds the stoppers and related industries. An integrated multilevel monitoring procedure was created in order to understand the dynamics of the cork oak system. In the frame of this monitoring system a single tree spatial growth simulation model (CORKFITS) was developed to be used as a decision management tool. This chapter describes the development of CORKFITS. The individual tree model was developed and tested in several areas of southern Portugal. The model showed successful performance in estimating the cork quantity values, when evaluating the calibration data set plots. The quality estimation required a recalibration of the cork growth model constructed on the first data set. New values of cork growth model coefficients are presented. A method for alternative data collection by means of remotely sensed imagery was developed. An algorithm for near infrared (NIR) aerial imagery was developed in order to obtain data on stand structure and individual tree characteristics necessary for simulation.