Investigating the relationship between dustiness indices and the aerosols optical depth around the Horulazim wetland

The phenomenon of dust in recent years has been one of the most important environmental challenges, which has been exacerbated by destructive human activities and has had adverse effects on the environment and human health. Considering that wetlands play an essential role in the balance of water and climate and also prevent the entry of fine dust; The present study was conducted with the aim of analyzing the relationship between the optical depth of aerosol particles (AOD) and the indices of dust-based soil in the area of Horulazim wetland. For this purpose, daily AOD product, MODIS sensor bands and hourly data of dust occurrences related to 3 meteorological stations of Ahvaz, Safi-Abad and Sulaiman masjed were obtained from their supply sources in a period of 18 years (2000-2018). Hourly data recorded in synoptic stations were used to calculate dust storm index (DSI) and MODIS sensor bands were used to extract BTD, BTDI, TIIDI, TDI, Miller and NDDI indices. Linear and non-linear regression methods were used to analyze the relationship between the mentioned indices and AOD. The results of the analysis of the relationship between DSI-AOD showed the very poor performance of this index in the analysis of dust events in all three study stations (R2<0.2). In Ahvaz, Safi Abad and Masjid Sulaiman masjed stations, the maximum value of R2 was observed between AOD-BTDI (0.48), AOD-Miller (0.503) and AOD-BTD (0.50), respectively. These results indicate that, on average, about 50% of the changes in the optical depth of aerosols can be explained using the three indices BTDI, Miller and BTD. Therefore, it is recommended to use these indicators in order to analyze the dust events around Horul Azim lagoon.