Habitat Selection to Reintroduce Iris bismarckiana in Semi-Arid Environments

Abstract

Conservation of endangered plant species in their indigenous regions is of crucial importance, especially for those grown in semi-arid regions. The objectives of this study were to explore the Nazareth iris’s (Iris bismarckiana) natural habitat and identify new suitable sites to initiate a reintroduction program of this endangered plant species in a semi-arid environment. The study was conducted in Dibbeen Forest Reserve, Jordan, where six zones inside the reserve [A–F] were assessed in addition to zone G outside the reserve borders that represents the area where I. bismarckiana still exists. Habitat selection variables (topography, soil physical and chemical properties, climatic data, and potential risks and benefits) from all zones within the reserve were cross matched with that of zone G. The results showed that climatic data of all selected sites were suitable for reintroduction; all sites are open to direct sunlight most of the day. The minimum soil depth was greater than 40 cm in all zones, while soil respiration level revealed that zone A (a recreation site) was below the recommended thresholds. The percentage of stone volume (>2 mm) in the soil profile was high in zones D and F. Zones E, C, and F were extremely steep (>40 degrees), which undermined their potential to be suitable habitats. All sites are susceptible to high human disturbance risk except zone B, which is protected and under continuous surveillance by the Reserve Botanist. Considering all measured suitability indicators, including slope degree suitability (<25), soil respiration (57–77 mg kg−1), soil stone percentage value (8.3%), tree canopy cover (open area), and human disturbance potential (low risk), zone B holds promise as a suitable site for a I. bismarckiana reintroduction program. Therefore, the initiation of long-term reintroduction programs within this site with timely surveillance is urgently needed to conserve and support such valuable species self-regeneration.