Nebkha, Indicator of changes in past environmental conditions on the Edge of the Lut Desert

Document Type : Original Article

Author

Department of Geography, Shiraz University, Shiraz, Iran

Abstract

Nebkhas affected by wind erosion in areas that have been and are vegetated form that is a function of wind regime, sediment load available habitat plant species and vegetation types are the Thus. This hill is the layering of sedimentary layering due to loss of moisture from the leaves of the tree or shrub and environmental conditions and characteristics of each type has its own environmental. This study tries to examine the environmental conditions in the Western lut Desert edge pay for the layering of sediments in the area are used Nebkhas layers. This research descriptive - analytical based on method field data, statistic and the library. That first field trip to the study area, nebkhas of using transects and plots were determined and then measure the morphometric characteristics of the species tamarix aphyla nebkhas. Next, a layer about 4 nebkhas, area sampling was carried out in different parts of the region and in the Laboratory, measurement of seed and plant material found in each of the samples was carried out to analyze the data collected. The results of the study indicate that the depth of about 2 meters elevation, area studies, about 5 layers can be detected that 5 layer is the result of a joint study on all nebkhas area is divided into 5 consecutive. Survey of sediment and organic matter in each layer that is present in the first period, which coincides there is a stable environment, but environment conditions in the second period, the first period was fluctuation. Peaceful environment in the region faced in the third period, but the fourth and fifth conditions in the region suggests that fluctuation. The fourth period of the oscillations was weaker than the processes in the context of the fifth round of stronger processes.

Keywords


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