Distribution modeling, soil properties, and variation in essential oils chemical composition of Rhanterium adpressum Coss. & Dur.

Modeling the distribution of Rhanterium adpressum, an endemic species from southwestern Algeria, and the interactions of soil’s chemical properties with the variability of chemical composition of its essential oils makes the objective of this study. Obtained MaxEnt model (AUC = 0.98) showed that the general distribution of genus Rhanterium established mainly by the contribution of eight bioclimatic variables derived from temperature and precipitation (90.5%). Projection of the model in future conditions until 2070 reveals that the habitats of this species will be very affected by climate changes. The analysis of 9 soil samples shows a sandy (77–96%), alkaline, and calcareous character with an electrical conductivity between 0.2 and 1.8 dS/m at 20°C. The chemical composition of terpenoids families during a period of 5 months was dominated by monoterpene hydrocarbons (70–90%) followed by oxygen monoterpenes (4.5–9.2%), hydrocarbon sesquiterpenes (1.6–9.9%), and oxygenated sesquiterpenes (4.3–7.2%). The variation of this composition in relation with phenological cycle and physicochemical properties of the soil was discussed.