2.1. Study Area
Iran, encompassing a vast area of 1,648,000 km², occupies a strategic position in southwest Asia, situated between 25°-40°N and 44°-63°E. The country exhibits diverse climatic conditions, with annual temperature fluctuations from 20°C to 50°C and annual rainfall varying between 120 mm to 2000 mm (Karimi et al., 2018; Farashi & Karimian, 2021). Notably, Iran boasts an extraordinary wealth of plant species due to its unique geographical location, serving as a confluence point for three prominent phytogeographical regions: the Irano-Turanian, Saharo-Sindian, and Europe-Siberian regions. This geographical convergence has rendered Iran’s plateau a cradle for evolution and a sanctuary for some of the planet’s oldest biodiversity. It functions as a crucial ecological bridge, facilitating the exchange of flora and fauna between Eurasia’s eastern and western regions (Noroozi et al., 2019).
The Saharo-Sindian phytogeographical region stretches across a vast expanse, encompassing the western territories of India, Pakistan, the southern periphery of Iran, including the Persian Gulf and the Oman Sea, the Arabian Peninsula, and Iraq, ultimately extending into North Africa. In Iran, this region is referred to as the Khalijo-Omanian zone, which encompasses seven provinces: Khuzestan, Kohgiluyeh-Boyer Ahmad, Fars, Bushehr, Hormozgan, Kerman, and Sistan-Baluchistan, all situated along the Persian Gulf. It is worth noting that the Khalijo-Omanian arid ecosystem experiences an average annual rainfall of less than 100 mm (Naderi Beni et al., 2021). The region’s summers are characterized by their protracted duration and extreme, parched heat (Sagheb Talebi et al., 2014).