Assessment of Chemical Characteristics of Airborne Dust over Shahdad Region, Iran by X-Ray Fluorescence (XRF) Analysis

Document Type : مقاله پژوهشی

Authors

1 isfahan university of technology

2 ferdowsi university of mashhad

Abstract

1. Introduction
Dust storm is a natural phenomenon that occurs frequently in the arid and semi-arid regions all over the world (Alijani, 1997). Dust can affect soil fertility, forests, rivers, lakes, and marine ecosystems around the world (McTainsh et al., 2007). Therefore, soil erosion can lead to the loss of the minerals and organic matter of topsoil. Some elements of dust have also an indirect effect on absorption of other elements (Reynolds et al. 2001). It is estimated that each year 2000 Mt dust is emitted into the atmosphere, 75% of which is deposited to the land and 25% to the ocean (Shao et al., 2011). The morphology and elemental composition of the particles can change alone the transportation in reaction to gasses and other particles in the atmosphere (Wang et al., 2007). Identification of the physical properties and chemical composition of dust aerosols is important to determine aerosol sources, mixing processes and transport pathways (Rashki et al., 2013). Chemical analysis of airborne dust can also characterize major and trace elements of airborne dust which is important for quantitative climate modeling, in understanding possible effects on human health, precipitation, ocean biogeochemistry and weathering phenomena (Goudie & Middleton, 2006)

2. Study Area
Shahdad is a region located in west of Lut Desert and South East Kerman province, in centre of Iran. Low precipitation, high temperature, salinity (Alavipanah, 2002) and sever winds are characteristic of this region. Shahdad with a maximum temperature of 71 ° C is one of the hottest regions in the earth (Alavi Panah, 2002, Mildrexler et al., 2006, Ehsani et al., 2008) this region with extensive wind erosion, and intense dust storms, causes adverse effects in regional air quality and human health. To mitigate the impact of these phenomena, it is vital to ascertain the chemical characteristics of airborne and soil dust

3. Material and Methods
This paper examines for the first time, the chemical properties of dust over Shahdad region by collecting dust samples at five stations established at 5 villages close to Lut desert downwind of dust source region, from spring 2013 to September 2013. Furthermore, soil samples were collected from topsoil (0-5 cm depth) at several locations in upwind areas. The data was analyzed to investigate the chemical characteristics of dust, relevance of inferred sources. X-ray Fluorescence (XRF) analysis of airborne and soil dust samples have been produced to show Chemical properties of dust and characterize major and trace elements.

4. Results and Discussion
Major-element and ion-chemistry analyses provide estimates of mineral components, which themselves may be hazardous to human health and ecosystems and can act as carriers of other toxic substances. X-ray Fluorescence (XRF) analyses of all the samples indicate that the most important oxide compositions of the airborne and soil dust are Silicon dioxide (SiO2) in quartz minerals, Calcium oxide (CaO) in calcite minerals and substantial Aluminum oxide (Al2O3) that exhibiting similar percentages for all samples. Chemical analysis of dust samples showed that the main element of dust in the Shahdad is SiO2 (49.35%), which is close to the average of this element in southeastern Iran( 47%) (Rashki et al., 2013) and more than Southwest Iran with (38%) (Zarasvandi et al., 2011). The global average SiO2 is 59.9%. Therefore, amount of Quartz in Iran is lower than Quartz the earth.
Major elements in the dust and soil samples in these analysis are: SiO2 (33.33-55.59%), LOI (12.68-26.31%), CaO (10.12-18.76%), Al2O3 (7.97-10.45%), a small amount of Fe2O3 (3.04-4.34%), Na2O (2.04-13.91%) , MgO (0-3.03%) and K2O (0.85-1.37%), as well as small amounts (

Keywords


براتی, غ., ح. لشکری و ف. کرمی (1390). "نقش همگرایی سامانه های فشار بر رخداد طوفان های غباری استان خوزستان." جغرافیا و توسعه 22: 39-56.
بهرامی, ح. (1390). "ریزگردها از نگاهی متفاوت." اولین کنگره بین المللی پدیده گرد و غبار و مبارزه با آثار زیانبار آن، رامین خوزستان.
سلوتی, س. م. بابانیانوری (1390). "بیابان گردی در ایران." انتشارات ایرانشناسی: 232.
علویپناه, س. ک. (1381). "مطالعه دمای پدیده های سطحی حاشیه یاردانگ های بیابان لوت با استفاده از مطالعات میدانی و داده های حرارت ماهواره " بیابان 7: 79-67.
علیجانی, ب. (1376). "آب و هوای ایران." انتشارات پیام نور.
A’rabi, M. (2005). Handbook of strategic planning. Publication of Office of Cultural research.
Abed, A. M.. Al Kuisi, M. M., & H. A. Khair, H. A. (2009). Characterization of the Khamaseen (spring) dust in Jordan. Atmospheric Environment, 43(18), 2868-2876.
Barati, Gh., Lashkari, K., & Karami, F. (2011). The role of convergence pressure system on dust storms in Khuzestan province. Geography and Development, 22, 39-56.
Colarusso, P, Guo, B, Zhang, KQ & Bernath, PF (1996). High-resolution infrared emission spectrum of strontium monofluoride. Journal of Molecular Spectroscopy, 175(1), 158-171.
Ehsani, A. H., & Quiel, F. (2008). Application of self organizing map and SRTM data to characterize yardangs in the Lut desert, Iran. Remote Sensing of Environment, 112(7), 3284-3294.
Goossens, D., & Offer, Z. Y. (1994). An evaluation of the efficiency of some eolian dust collectors. Soil Technology, 7(1), 25-35.
Goudie, A. S., & Middleton. N. (2006). Desert dust in the global system. Springer.
Hojati, S., Khademi, H., Faz Cano. A., & Landi, A. (2012). Characteristics of dust deposited along a transect between central Iran and the Zagros Mountains. CATENA, 88(1), 27-36.
Kasper-Zubillaga, J. J., Acevedo-Vargas, B., Bermea, O. M., & G. O. Zamora, G. O. (2008). Rare earth elements of the Altar Desert dune and coastal sands, Northwestern Mexico. Chemie der Erde-Geochemistry, 68 (1), 45-59.
Leinen, M., Prospero, J. M., Arnold, E., & Blank, M. (1994). Mineralogy of aeolian dust reaching the North Pacific Ocean: Sampling and analysis. Journal of Geophysical Research: Atmospheres, 99(D10), 21017-21023.
Lue, Y., Liu, L., Hu, H., Wang, L., Guo, L., Gao, S., Zhang, X., Tang, Y., Qu, Z., & Cao, H. (2010). Characteristics and provenance of dustfall during an unusual floating dust event. Atmospheric Environment, 44(29), 3477-3484.
McTainsh, G., & Strong. C. (2007). The role of aeolian dust in ecosystems. Geomorphology, 89(1–2), 39-54.
Mildrexler, D., Zhao. M., & Running. S. (2006). Where are the hottest spots on Earth? Eos, Transactions American Geophysical Union, 87, 461-467.
Movchan, B.,& Demchishin, A. (1969). Structure and properties of thick condensates of nickel, titanium, tungsten, aluminum oxides, and zirconium dioxide in vacuum. Fiz. Metal. Metalloved, 28, 653-60.
Rashki, A., Eriksson, P. G., Rautenbach, C. J. d. W. Kaskaoutis, D. G., Grote, W., & Dykstra, J. (2013). Assessment of chemical and mineralogical characteristics of airborne dust in the Sistan region, Iran. Chemosphere, 90(2), 227-236.
Reynolds, R., Belnap, J., Reheis, M., Lamothe, P., & Luiszer, F. (2001). Aeolian dust in Colorado Plateau soils: Nutrient inputs and recent change in source. PNAS, 98(13), 7123- 7127.
Selooti, S. M., & D. Babanianuri, D. (2011). Desert tourism in Iran. Iran shenasi Publications: 232. [in Persian]
Shao, Y., Wyrwoll, K. H., Chappell, A., Huang, J., Lin, Z., McTainsh, G. H., Mikami, M., Tanaka, T. Y., Wang. X., & Yoon, S. (2011). Dust cycle: An emerging core theme in Earth system science. Aeolian Research, 2(4), 181-204.
Wang, X., Wang, T., Dong, , Z., Liu, X., & Qian, G. (2006). Nebkha development and its significance to wind erosion and land degradation in semi-arid northern China. Journal of Arid Environments, 65(1), 129-141.
Wang, Y., Zhuang, G., Tang, A., Zhang, W., Sun, Y., Wang, Z., & An. Z. (2007)The evolution of chemical components of aerosols at five monitoring sites of China during dust storms. Atmospheric Environment, 41(5), 1091-1106.
Wang, Y., Zhuang, G., Zhang, X., Huang, K., Xu, C., Tang, A., Chen. J., & An, Z. (2006). The ion chemistry, seasonal cycle, and sources of PM2.5 and TSP aerosol in Shanghai." Atmospheric Environment, 40(16), 2935-2952.
Wu, G., Xu, B., Zhang, C., Gao. S., & Yao. T. (2009). Geochemistry of dust aerosol over the Eastern Pamirs. Geochimica et Cosmochimica Acta 73(4):977-989
Zarasvandi, A., Carranza, E. J. M., Moore. F., & Rastmanesh, F. (2011). Spatio-temporal occurrences and mineralogical–geochemical characteristics of airborne dusts in Khuzestan Province (Southwestern Iran). Journal of Geochemical Exploration, 111(3), 138-151.
Zhang, D. D., Peart, M., Jim, C., He, Y., Li., B., & Chen, J. (2003). Precipitation chemistry of Lhasa and other remote towns, Tibet. Atmospheric Environment, 37(2), 231-240.
CAPTCHA Image