Comparative analysis of forest soil properties from sub-humid and semi-arid areas of Djebel El Ouahch biological reserve in Algeria

The forest plays a vital role in the biological, ecological and economic balance in our country. It is the result of millenary interactions between the climate, the diversity of geological and edaphic contexts. The objective of this study was to determine and evaluate the physicochemical parameters of forest soils in two zones of the Djebel El Ouahch (Constantine) national park, which were exposed to two bioclimatic stages (sub-humid and semi-arid). The samples were taken at a depth between 0 and 20 cm in each zone on sampling stations of 400 m2. Our results showed that the bioclimatic stage affected the physico-chemical properties of the soils by increasing the percentage of humidity, the rate of carbon, nitrogen and organic matter in the sub-humid zone, on the other hand in the semi-arid zone are vulnerable and fragile due to their texture, a low water retention capacity, the rate of degradation of organic matter and a high rate of total limestone. The intense drying and the vulnerability of the soils in the semi-arid zone could reduce the long-term physico-chemical fertility with the consequence of a regression of the vegetation and the alteration of the biodiversity.