مشخصات پژوهش

Dust Phenomenon is considered as one of the biggest environmental problems in various parts of the world. Most of the dust existed in the atmosphere are originated from fine-grained particles. The tiny particles are more abundant in arid and semiarid regions of the world. In these areas lakes and wetlands are natural dust traps and core sampling method can be an appropriate way to assess the phenomenon of the dust. Therefore, the purpose of this study was the study of frequency and characteristics of dust sediments in core sampls from hashylan wetlands, kermanshah. Four intact core samples were taken from different parts of the Hashilan wetland in Kermanshah. Physical, chemical and micromorphological analysis were done. Also clay mineralogy was performed using X-ray analysis (XRD) and Shape of particles were photographed by scanning electron microscope (SEM). Results showed that samples 3, 1, 2 and 4, respectively, had the highest amounts of dust deposits. Considering that four samples had been taken from different parts of the wetland, the quantitative differences in dust amount is likely due to the location of the samples. There was no difference in types of particles in various parts of the samples, which indicated that deposited dust in different depositional sequences originated from the same source. The results of XRD and thin sections showed that the dominant mineralogical composition of dust particles were clay minerals, quartz and calcite and they were abundant mostly at top 30 cm of core samples and over newly decomposing organic tissues. SEM results for core sample1 revealed that most particles had the size between 2 to 50 mm which ranges from fine silt to coarse silt. Considering the similarities between SEM images for core sample1 and those from Kermanshah dust measurement station, it could be said that fine rounded particles detected at top 30 cm of core samples have Aeolian origin. These findings were in accordance with the results from dust measureme