Reconstructing the Environmental Changes in the Western Border of Lut Plain Based on the Study of Nebkhas

Document Type : Research Article

Authors

1 Assistant Professor, Department of Geography, Faculty of Economics, Management & Social sciences, Shiraz University, Shiraz, Iran

2 Associate Professor, Department of Geography, Golestan University, Gorgan, Iran

Abstract

 
In the old Lut playa underneath the hills of nebkhas, the deepening of the waterways and the extent of the expansion of the cones and the nebkha morphometry are evidences of environmental changes. To study the above-mentioned factors, it is necessary to rebuild the morphodynamic conditions of the region. In this research, the changes in environmental conditions of the area are investigated and rebuilt using the phytogenic hills of nebkha. Sampling was done by carving a surface on the sediments of nebkhas and specifying their layers. The sampled sediments were then studied in a geochemical lab and their age was estimated in a lab in Poznan in Poland, where they were sent. The results show that the region in a period of 735 years of the life of the Nebkhas has gone through several levels of environmental changes. The most intense processes and the wettest period among the studied periods belong to the third period about 735 years ago. These results were gathered by geochemical experiments such as the amount of organic matter, salt and lime on the layers of the sediments. The driest period among the periods studied is the 11th period, which took place around 114 years ago. The least intense processes with the lowest amount of humidity (according to the results related to the amount of organic matter in the sediments) were in this period.

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References

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Journal of the Earth and Space Physics
Volume 45, Issue 4
February 2020
Pages 203-217

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