Particles size distribution of Lake Urmia area soils erosion sampling by BSNE sampler

Recently, the Lake Urmia has become one of the key dust sources in Iran due to a sharp drop in its water level. One of the essential information to decide how to deal with this problem is to know the distribution of the particles size carried at different heights above the soil surface. In order to trap the dust particles of the Lake Urmia area soils erosion, one of dust centers that was located in the southeastern of the Lake Urmia in 30 kilometers distance from the Tabriz-Azarshahr road was selected and the BSNE samplers (Big Spring Number Eight) were used. 14 pole, each of which had 4 samplers at 0.15, 0.5, 1 and 2 m heights above the soil surface were installed in a circle pattern. The samplers were evaluated in 12 interval periods (March 2016-February 2017) and the particle size distribution and the vertical profile of gathered particles were determined. Results showed that the amount of fine particles (0.15-0.053 mm) was greater than the coarse particles (1-0.25 mm). The highest amount of the fine particles was obtained at 100 and 200 cm and of the coarse particles was obtained at 15 cm height above the soil surface. When the height above the soil surface increased, the weight of gathered particles decreased. The power function was the best to explain changes between the weight of gathered particles and the height above the soil surface. There was a negative correlation between monthly rainfall and the weight of gathered particles.