Assessment of the distribution and activity of dunes in Iran based on mobility indices and ground data

Sand dune movement causes severe damage to infrastructure and rural settlements in Iran every year. Identifying active dunes and monitoring areas with migrating sand are important prerequisites for mitigating these damages. With regard to this objective, the spatial variation of the wind energy environment based on the sand drift potential (DP) was calculated from 204 meteorological stations. Three commonly used dune activity models - the Lancaster mobility index (1988), the Tsoar mobility index (2005), and the index developed by Yizhaq et al. (2009) - were used for the evaluation of Iran's sand dune activity. The analysis of the indices showed that the dune activity was characterized by great spatial variation across Iran's deserts. All three models identified fully active dunes in the Sistan plain, the whole of the Lut desert, as well as in the Zirkuh Qaien and Deyhook regions, while the dunes in the northern part of Rig Boland, Booshroyeh and in the Neyshabor dunefields were categorized as stabilized dunes. For other dunes, the models show a less unified activity classification, with the Lancaster and Yizhaq models having more similar results while the Tsoar model stands more apart. Based on these model results and fields observations, a modified Lancaster mobility index has been applied to show a more realistic spatial variation of sand dunes activity in Iran's desert areas.