Effect of Pinus halepensis reforestation on soil fertilityin the forest of Beni Sohane (Ribat Al Kheir Region -Morocco)

Abstract

The purpose of this study is to determine the effect of reforestation of Pinus halepensis on soil fertility in the Beni Sohane forest. The Physico-chemical analysis was carried out on 24 soil samples collected at two depths of 0-10 cm and 10-30 cm. The soil samples were collected from 45-year-old reforested plots and native forest controls. The results revealed that reforestation with P. halepensis did not affect the pH, while it had negative effects on the content of all other nutrients, especially for Olsen phosphorus and boron, whose levels were significantly lower than those recorded in the native forest. The negative impact of reforestation was most accentuated in the topsoil layer of 0-10 cm. At this layer, the average content of all nutrients was -39% lower than the average content of the native forest, while at a depth of 10-30 cm it was only -18%. It seems that the sustainable restoration of degraded lands would depend on the prevalence of ecological considerations, favoring native forest species rather than expansionist exotic species such as P. halepensis.