New angular competition index and tree crown projection model

Tree architecture plasticity enables individuals to maximize filling of the available space and minimize the competition effect; tree crowns can be distributed more regularly than stem bases. We conducted a study in a temperate mixed forest (Krakow, Poland) to test the idea of a new angular competition index (CI) and its application in modeling crown radii (CR) and crown projections (CPs) of 30 Quercus robur trees. The statistical method used was random forest algorithm. The model allows the prediction of the CP shape on the basis of stem spatial distribution and diameter, measurement of two CR per target tree and local topography; it can be used to compare the inter- and intra-specific architectural plasticity of the canopy trees.

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