Descriptive crown models for Laurel (<em>Cordia alliodora</em>) under agro forestry systems of the Protected Forest Sumaco, Ecuador

Abstract

The ability to describe the shape and size of a tree crown is an important pre-requisite for the estimation of the stability of standing forest trees. The paper describes a crown model for laurel in agro forestry systems of the Protected Forest Sumaco. The empirical data base includes altogether 207 Laurel sample trees. A stem analysis was carried out for each sample tree crown ratio, crown length, crown surface area and crow projection. The sample trees were grown in 3 agro forestry stands which had been subjected to different thinning regimes. To determine the crown width a lineal relationship existed between DBH and crown width. The modification of the models in direction toward a non-lineal relationship not showed improvements in the estimate of this parameter. The crown base, the model proposed by Dursky (2000) was demonstrated the best r2 (0.84). The distortion value of this model was closed to the ideal value of 0 (0.0083) and mean squared error was 1.49 m.This model was adjusted to the characteristics of Laurel. It was developed a model in order to determinate the crown length. The model presented an r2 of 0.71. This means that, 71% of total variance observed in Laurel can be explained for this parameter. The developed models of this research could be used to establish and calculate other forest attributes of Laurel.

Keywords

• ancho de la corona
• base de corona
• largo de la corona
• radio de la corona
• proyección de corona