عنوان مقاله [English]
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.
Barzani, M. M., & Khairulmaini, O. S. (2013). Desertification risk mapping of the Zayandeh Rood Basin in Iran. Journal of earth system science, 122(5), 1269-1282.
Bourke, M. C., Ewing, R. C., Finnegan, D. and McGowan, H. A., 2009, Sand dune movement in the Victoria Valley, Antarctica, Geomorphology, 109, 148–160.
Christopher, L., Seifert R., Steven, L., Forman, L., Foti, A., Wasklewicz, A. and McColgan, T., 2009, Relict Nebkhas (pimple mounds) record prolonged late Holocene drought in the forested region of south-central United States, Quaternary Research, 71, 329–339.
Deotare, B. C., Kajale, M. D., Rajaguru, S. N., Kusumgar, S., Jull, A. T., & Donahue, J. D. (2004). Palaeoenvironmental history of Bap-Malar and Kanod playas of western Rajasthan, Thar desert. Journal of Earth System Science, 113(3), 403-425.
Lang, L., Xunming, W. and Caixia, Zh., 2013, Moisture availability over the past five centuries indicated by carbon isotopes of Tamarix taklamakanensis leaves in a Nebkha profile in the Central Taklimakan Desert, NW China, Aeolian Research, 17, 50-68.
Mahmoudi, F., 1977, Birth and death of Nabaka. Journal of Faculty of Literature & Humanities University of Tehran, 97, Page 299.
Marwati Sharif Abad, A., 2001, Study of the relationship between erodibility of surface soil by wind and its physical and chemical properties in Rudasht region of Isfahan. Master thesis of Soil Science, Isfahan University of Technology.
Maghsoudi, M., 2006, Identification of effective processes on the development and evolution of sand complications (Case study: Complications of Sirjan pit sand), Geographical Research Journal, 56, 149 - 160.
Motamed A., 1990, Investigation of the Origin and Disposition of Sands in the Basin of Kashan. Tehran University Press.
Musick, H. B. and Gillette, S. M., 1996, Wind-tunnel Modeling of the Inﬂuence of Vegetation Structure on Saltation Threshold, Earth Surface Processes and Landforms, 21, 589-606.
Pourkhosravani, M., Vali, A. and Movahedi, S., 2010, Comparative grouping of Sidlitziafluridae, Romarita-kastanica and Alhaji-Manifera based on the vegetative forms of plants in the Kheyrabad region of Sirjan. Quarterly Journal of Geographic Space, 9(31), 158-137.
Pourkhosrowani, M., Vali, A. and Moeeri, M., 2009, Investigation of the relationship between plant morphology and morphometric characteristics of Nebacca spp, Journal of Natural Geographical Research, 69, 113-109.
Rafahi, H., 2004, Wind Erosion and its Control. Tehran University Press, Third edition, Tehran.
Sauermann, G., Andrade Jr., J. S., Maia, L. P., Costa, U. M. S., Ara`ujo, A. D. and Herrmann, H. J., 2003, Wind velocity and sand transport on a barchan dune, Geomorphology, 132, 1–11.
Sauermann, G., Kroy, K. and Herrmann, H. J., 2001, Continuum saltation model for sand dunes, Phys. Rev., E 64(3), 031305–1–10.
Tengberg, A. and Chen, D., 1998, A comparative analysis of Nebkha in central Tunisia and northern Burkina Faso, Journal of Geomorphology, 22(2), 181-192.
Tsoar, H., 2005, Sand dunes mobility and stability in relation to climate, Physica A, 357, 50–56.
Tsoar, H. and Møller, J. T., 1986, The Role of Vegetation in the Formation of Linear Sand Dunes’, in Nickling, W.G. (Ed.), Aeolian Geomorphology, Allen and Unwin, Boston.
Vali, A. and Pourkhosrowani, M., 2009, Comparative analysis of the relationship between Nebka morphometric components and plant morphology of Tamarix mascatensis, Reaumuria turkestanica and Alhagi mannifera species in Kheirabad, Sirjan. Journal of Geography and Environmental Planning, 35(3), 134-119.
Wang, X., Zhang, C., Zhang, J., Hua, T., Lang, L., Zhang, X. and Wang, L., 2010, Nebkha formation: Implications for reconstructing environmental changes over the past several centuries in the Ala Shan Plateau, China, Journal of Palaeogeography, Palaeoclimatology, Palaeoecology., 297, 697–706.
Wiggs, G.F.S., Thomas, D.S.G., Bullard, J.E. and Livingstone, I., 1995, Dune Mobility and Vegetation Cover in the Southwest Kalahari Desert, Earth Surface Processes and Landforms, 20, 515-530.
Wolfe, S. A. and Nickling, W. G., 1993, The Protective Role of Sparse Vegetation in Wind Erosion, Progress in Physical Geography, 17, 50-68.