A comprehensive survey of halophytes in Khorasan province of Iran

Abstract

Khorasan province in the North East of Iran is the largest state in the country and occupies one fifth of the land surface of the country which is more than 300,000 km². This province has a diversity of climatic conditions and large borders with two main deserts of the country, Kavir Loot and Kavir Namak. The altitude, the location of plateaus, and the deep valleys are some of the most important causes of this diverse climate. Khorasan has four main climatic zones such as steppic, substeppic, subdesertic and mountainous. Mean annual precipitation of this province is less than 220 mm/year. Because of the saline ground water, the presence of a salt layer in the soil, intense irrigation, high evaporation and low precipitation, there is a large saline area in this part of the country. Despite a rich halophytic flora in the province, halophytic communities are poorly known vegetation units.