Pedogenetic characterization and classification of forest soils in the Central Middle Atlas (Morocco)

Abstract

The study was carried out in the forests of the Central Middle Atlas where the soils have a Mediterranean character. The forest formations found include resinous species such as on Atlas cedar (Cedrus atlantica) and maritime mountain pine (Pinus pinaster), and deciduous species of green oak (Quercus rotundifolia) and zeen oak (Quercus canariensis). The morphological description of soils' genetic horizons was based on the opening of soil pedons in the forest formations composing the studied area. Then, physical and chemical characterization of the studied soils was analyzed. According to the Commission of Pedology and Soil Mapping (CPCS, 1967) principles and those of the international system of classification, nomenclature and soil mapping used by FAO (2015), three types of soils were identified as dominant in these forests, namely, the class of browned soils, iron sesquioxide soils and calcimagnesic soils. As a result, they differ in their responses to management practices, their inherent ability to deliver ecosystem services, as well as their resilience to disturbance and vulnerability to degradation.

Assessment of the organic carbon stock in the green oak forest in the Morrocan Oulmes Central Plateau

“… Total nitrogen: the analysis of this parameter was carried out using the Kjeldahl/ Wilke (2005) [9,10,11] distillation method ;…”

“… Organic carbon and organic matter: the analysis of soil organic carbon was carried out using the method of Walkley and Black (1934) [10,11,12] and the value of organic matter was deduced from the formula of Soltner (1988) [13] ;…”

“…For our case study, we used the models for estimating the biomass of green oak trees developed by Belghazi et al (2001) [5] (Table I), in the central plateau of Oulmés bordering our studied area and comparable to our context. In addition, these models were validated on a sample of ten (10) felled green oak trees, on which direct measurements of the fresh mass of the different compartments were carried out [19]. Thus, for all the standing trees, we proceeded to the measurement of the circumference at 1.30 m height, and for each tree, the different compartments were separated, and the measurements concerned :…”