Analysis of diameter distributions and conservation of forests of northern Morocco

Abstract

The analysis of diameter distributions for different tree populations in a forest, allows to evaluate its ecological and conservation conditions. In particular, this type of analysis allows to detect a lack of regeneration or an ageing trend. A total of 84 samples of native forests have been studied in the Tingitanian Peninsula, northern Morocco. Forests of Quercus suber and Q. canariensis tend to have an assimetric, positive diameter distribution; this pattern reflects a lack of regeneration. Forests of Cedrus atlantica have a great proportion of small-diameter trees, indicating a recovering stage after past massive logging. Forests of Pinus pinaster var. maghrebiana have a relative higher number of trees within the intermediate size classes, indicating an ageing trend. Sacred forests or morabitos are usually dominated by large, old trees of Quercus suber ; in some cases, tree-sized Quercus coccifera and Phillyrea latifolia are dominant.