Nutritional Value Study Of Some Spontaneous Species From Saharan Rangelands: Case Of The Ouargla Region, Algeria

Abstract

Rangelands in Saharan regions are characterized by high geomorphological heterogeneity, which induces a specific floristic diversity for each ecosystem, associated with a highly significant difference in species density (p < 0.001). This spatio-temporal complementarity provides herders with opportunities for selective transhumance to meet livestock requirements throughout the four seasons of the year. In the present study, a floristic characterization of several rangeland types was carried out, and the nutritional value of their main spontaneous species was evaluated.The results revealed that the rangeland type exerts a highly significant effect on vegetation canopy cover (p < 0.001). Within the "wadi beds" rangeland, Limoniastrum guyonianum displayed the highest cover (17.4 m³), while the lowest was recorded for Salicornia strobilacea(0.003 m³). Across all studied rangelands, the vegetation structure remained scattered, with an abundance-dominance index not exceeding a value of 2.Regarding the nutritional evaluation, deep interspecific contrasts were highlighted. The highest energy values were recorded for Salicornia strobilacea (0.86 UFL and 0.81 UFV / kg DM), whereas the lowest were attributed to Stipagrostis pungens(0.38 UFL and 0.35 UFV kg DM). In terms of nitrogen value, Malcolmia aegyptiaca exhibited the highest contents (91 g PDIE and 82g PDIN / kg DM), while Stipagrostis pungens showed the lowest value (49 g PDIE and 26 g PDIN / kg DM).