Dust Deposition Rate and its Relationship to Some Climatic Parameters in Khorasan Razavi Province

Document Type : مقاله پژوهشی

Authors

1 Ferdowsi University of Mashhad

2 Isfahan University of Technology

Abstract

Introduction

Airborne dust is an important environmental hazard in arid and semi-arid regions. Dust deposition rate is one of the most important characteristics of airborne dust which needs to be measured for risk assessment and source determination. During the past decade, by increasing the dust deposition in Iran, many investigations have been conducted to document the dust deposition characteristics and identify the regional atmospheric and land surface processes controlling dust transport. The objective of this study is to measure the dust deposition rate and investigate the effect of climatological factors on airborne dust in Khorasan Razavi Province located in the northeast of Iran.

Materials and Methods

Khorasan Razavi Province is located in the northeast of Iran. Elevations range from 235 m in Sarakhs in east to 3211 m at Binaloud Mountain in north of the area. Mean annual precipitation varies from 111.5 to 306.3 mm and the mean annual temperature is between 12.7°C to 18.9°C. The Kopeh Dagh and Binaloud Mountains are in the northern part of the area. There are several playas (including clay flats, salt crusts, and sand dunes) in the south and western of the Province. Airborne dust samples were collected monthly from May 2014 to April 2015. A dry flat collection tray with an area of 1 m2 was used to sample airborne dust. Fifty trays were placed on the roof of buildings ~3- 4 m above the ground level. Dust trapped on the trays were collected by a rubber spatula and then were weighted. Totally, 600 samples were collected from 50 sites in the Province. Interpolation in this study was carried out using surfer software 14. Furthermore, the Grads software was used to draw the average monthly wind speed, direction patterns, and synoptic pattern of dusty days. The Pearson coefficient was used to determine the correlation between the characteristics with normal distribution.

Results and Discussion

The measured dust deposition rate indicated the significant spatial and temporal variations during the studied period. The lowest and highest average monthly dust deposition was 9.97 and 20.96 g m-2 which occurred in December and June, respectively. The annual dust deposition rate showed high variations from 313.14 g m-2 y-1 in Gonabad with desert climate regime in southern to 74.62 g m-2 y-1 in the city of Quchan with temperate-mountainous climate in northern part of the area. In spring and summer, the dust deposition rate was the highest in the west and the south of the Province and also indicated the high range of variations. In autumn and winter, the range of dust deposition rate decreased and also the highest amount of deposition occurred in the east. The lowest amount of deposition was found in the mountainous northern part of the area. There was a significant positive correlation between the average dust fallout and the mean wind velocity and the maximum and minimum monthly air temperatures, while there is a significant negative correlation between this parameter and relative humidity. The spatial distribution analyses showed the highest amount of dust fallout in the southern and western parts of the Province, which includes the desert and sub-desert climate and also the most storm occurrences in spring. Also, in the months with higher rainfall, the amount of fallout rates decreased in most areas except the east of the Province. The high speed of wind, the dryness of the soil and the high occurrence of dust storm in June and July have caused the dust to be carried a long distance as compared with other months.

Conclusion

The results of this study indicated the hazard of dust deposition rate, especially in the south and west of the Khorasan Razavi Province in spring and summer. The dust deposition was the highest in the areas at margin of the desert with low relief, sparse vegetation and high wind velocity. Monthly variations in dust fallout rates were related to some climatological parameters. There was a significant positive correlation between the average atmospheric airborne dust fallout in 12 sampling intervals, the maximum and minimum temperatures, and wind speed and there was a significant negative correlation between this parameter and relative humidity at P-value<0.05. These findings are closer to the results of Noroozi and Khademi (2015) (in Isfahan), Al-Harbi (2015) (in Kuwait), and Kaskaoutis, et al. (2016) (in the southwest of Asia). Furthermore, through the change of the direction in prevailing winds from east and northeast in dry months to the west and northwest, the rate of airborne dust fallout declined in most regions in the months with more precipitation, but not in the east of the Province where the area was exposed to the highest wind speed in spring and summer. It is noted that the increase of temperature causes a decrease in soil moisture; this issue is, in turn, considerably important in decreasing the speed of the threshold, which consequently increases the wind force and soil movement (Rahimi, 2015). In addition, rainfall and temperature can indirectly play an effective role in amount of the fallout rate through affecting vegetation due to the effect of these two parameters on the plant coverage (Makhdoum, 2006). The results of the analysis of climatic synoptic maps related to stormy days in the sea level pressure map showed that the establishment of the cyclone center in Afghanistan and the south of Khorasan, and the anticyclone center on the Caspian Sea and Turkmenistan cause heavy winds and dust storms in the region. Considering the geographical location of the Province (sharing borders with both Turkmenistan and Afghanistan) and the wind direction, it could be suggested that the sources of these storms are found in the surrounding areas. However, the determination of the source of the atmospheric suspended particles in Khorasan Razavi Province requires further study and more comprehensive laboratory analyses.
 

Keywords


احمدی دوآبی، شهاب؛ افیونی، مجید؛ کرمی، مهین؛ خادمی، حسین؛ 1392. نرخ فرونشست گرد‌وغبار اتمسفری در استان کرمانشاه در بهار و تابستان. سومین همایش ملی فرسایش بادی و طوفان‌های گرد و غبار، یزد.
بروغنی، مهدی؛ مرادی، حمیدرضا؛ زنگنه اسدی، محمدعلی؛ 1394. تحلیل وقوع گرد و غبار و پهنه بندی آن در استان خراسان رضوی مجله پژوهش‌های فرسایش محیطی. شماره 20،57-45.
بیت لفته، رضا؛ لندی، احمد؛ حجتی، سعید؛ صیاد، غلامعلی؛ 1394. نرخ ترسیب، کانی‌شناسی و الگوی توزیع اندازه ذرات گرد‌و‌غبار در اطراف تالاب هورالعظیم در استان خوزستان. نشریه آب و خاک (علوم و صنایع کشاورزی). شماره 29، 707-695.
جعفری، فریبا؛ 1392. نرخ فرونشست و برخی خصوصیات شیمیایی و کانی‌شناسی گرد‌و‌غبار اتمسفری در شهر کرمان. پایان‌نامه کارشناسی ارشد. حسین خادمی. خاکشناسی، دانشگاه صنعتی اصفهان.
دوستان، رضا؛ 1392. شناسایی کانون‌های فشار مؤثر در وقوع باد 120 روزه سیستان و بلوچستان. نخستین کنفرانس ملی آب و هواشناسی ایران. کرمان.
رحیمی، محمد؛ یزدانی، محمد‌رضا؛ اسدی، مسلم؛ حیدری، محمد‌طالب؛ 1394. بررسی آلودگی هوای شهر سنندج با تاکید بر تغییرات زمانی غلظت10PM. دو فصلنامه پژوهش‌های بوم شناسی شهری. شماره 11، 116-99.
سازمان هواشناسی استان خراسان رضوی؛ 1389و 1394.
لشکری، حسن؛ کیخسروی، قاسم؛ 1387. تحلیل آماری سینوپتیکی توفان‌های گرد و غبار استان خراسان رضوی در فاصله زمانی (2005 1993). فصلنامه پژوهش‌های جغرافیای طبیعی. شماره 65، 33-17.
محمدیاریان، محترم؛ 1390. پهنه‌بندی مخاطرات جوی در شمال شرق ایران. پایان‌نامه کارشناسی ارشد. استاد راهنما: عباس مفیدی. آب و هواشناسی، دانشگاه فردوسی مشهد.
محمودی، زهره؛ 1390. بررسی خصوصیات ژئوشیمیایی و کانی‌شناسی گرد‌و‌غبار اتمسفری اصفهان. پایان‌نامه کارشناسی‌ ارشد. استاد راهنما: حسین خادمی. خاکشناسی، دانشگاه صنعتی اصفهان.
مخدوم، مجید؛ 1385. شالوده آمایش سرزمین. انتشارات دانشگاه تهران.
ممرآبادی، پروین؛ 1395. تغییرات زمانی و مکانی شاخص‌های گردوغبار در شرق خراسان و اثرات تغییرات کاربری اراضی بر آن. پایان نامه کارشناسی ارشد، استاد راهنما: علی‌رضا راشکی. مدیریت مناطق بیابانی. دانشگاه فردوسی مشهد.
نوروزی، سمیرا؛ خادمی، حسین؛ 1394. تغییرات مکانی و زمانی نرخ فرونشست گرد و غبار در شهر اصفهان و ارتباط آن با برخی پارامترهای اقلیمی. مجله علوم و فنون کشاورزی و منابع طبیعی. علوم آب و خاک. شماره 72، 161-149.
AL-Harbi, M., 2015. Characteristics and composition of the falling dust in urban environment. Int. J. Environ. Sci.Technol. 12: 641-652.
Conference on Dust, 2-4 March 2016, Shahid Chamran University, Ahvaz, Iran.
Engelstaedler, S., Tegen, I., and Washington, R., 2006. North African dust emissions and transport. Earth Sci. Rev. 79:73-100.
Goudie, A.S., and Middleton. N.J., 2006. Desert Dust in the Global System. Springer Verlag. Berlin, Germany.
Groll, M., Opp, C., and Aslanov, I., 2013. Spatial and temporal distribution of the dust deposition in Central Asia results from a long-term monitoring program. Aeolian Res. 9: 49-62.
Hamidi, M., Kavianpour, M.R., Shao, Y., 2013. Synoptic analysis of dust storms in the Middle East. Asia-Pac. J. Atmospheric. Sci. 49:279-286.
Hojati, S., Khademi, H., Faz Cano A., and Landi, A., 2012. Characteristics of dust deposited along a transect between central Iran and the Zagros Mountains. Catena. 88: 27-36. http: //lance-modis.eosdis.nasa.gov.
Kaskaoutis, D.G., Rashki, A., Houssos, E.E., Bartzokas, A., Francois, P., Legrand, M., and Kambezidis, H.D., 2016. The Caspian Sea–Hindu Kush Index (CasHKI): definition, meteorological influences and Dust activities over southwest Asia. The First of International
Marx, S.A., McGowan, H.A., 2005. Dust transportation and deposition in a superhumid environment, West Coast, South Island, New Zealand. Catena. 59: 147-171.
McTainsh, G.H. 1999. Dust transport and deposition. PP. 181-211. In: Goudie, A., S. Livingstone and I. Stokes(Eds.), Aeolian Environments, Sediments and Landforms. John Wiley and Sons, Ltd, Chichester.
Menendez, I., Diaz-Hernandez, J. L., Mangas, J., Alonso, I., and Sanchez-Soto, P.J., 2007., Airborne dust accumulation and soil development in the North-East sector of Gran Canaria (Canary Islands, Spain). J. Arid. Environ. 71: 57-81.
Naddafi, N., Nabizadeh, R., Soltanianzadeh, Z. and Ehrampoosh. M.H., 2006. Evaluation of dust fall in the air of Yazd. Journal of Environmental Health Science Engineering. 3: 161-168.
National Oceanic and Atmospheric Administration Earth System Research Laboratory (http://www.esrl.noaa.gov).
OHara, S.L., Clarke, M.L., and Elatrash, M.S., 2006. Field measurements of desert dust deposition in Libya. Atmos. Environ. 40: 3881-3897.
Prospero, J.M., Ginoux, P., Torres, O., Nicholson, S.E., and Gill, T.E., 2002. Environmental characterization of global sources of atmospheric soil dust identified with the Nimbus 7 total ozone mapping spectrometer absorbing aerosol product. Rev. Geophys. 40: 2-31.
Rashki, A., Kaskaoutis, D.G., deW. Rautenbach, C.J., Eriksson, P.G., Qiang, M., and Gupta, P., 2012. Dust storms and their horizontal dust loading in the Sistan region, Iran. Aeolian Res. 5: 51-62.
Reheis, M.C., and Urban, F.E., 2011. Regional and climatic controls on seasonal dust deposition in the southwestern U.S. Aeolian Res. 3: 3-21.
Rezazadeh, M., Irannejad, P., Shao, Y., 2013. Climatology of the Middle East dust events. Aeolian Res. 10:103-109.
Ta, W., Qu, H., Xiao, J., Xiao, Z., Yang, G., Wang, T., and Zhang, X., 2004. Measurements of dust eposition in Gansu Province, China, 1986–2000. Geomorphology. 57:41-51.
Tegen, I., Werner, M., Harrison, S.P., and Kohfeld, K.E. 2004., Relative importance of climate and land use in determining present and future global soil dust emission. Geophysical Research Letters. 31 (5): 1-4.
Wang, R., Zou, X., Cheng, H., Wu, X., Zhang, C., and Kang, L., 2015. Spatial distribution and source apportionment of atmospheric dust fall at Beijing during spring of 2008-2009. Environ. Sci. Pollut. Res. 22: 3547-3557.
Wang, S., Yuan, W., and Shang, K., 2006. The impacts of different kinds of dust events on PM10 pollution in northern China. Atmos. Environ. 40: 7975-7982.
Wiggs, G.F.S., O'hara, S.L., Wegerdt, J., Van Der Meer, J. and Small. I., 2003. The dynamics and characteristics of aeolian dust in dryland Central Asia: Possible impacts on human exposure and respiratory health in the Aral Sea basin. Geographical Journal. 169(2): 142–157.
Xuan, J., Sokolik, I.N., Hao, J., Guo, F., Mao, H., and Yang, G., 2004. Identification and characterization of sources of atmospheric mineral dust in East Asia. Atmos. Environ. 38: 6239-625.
Zawar-Reza, P., Kingham, S., Pearce, J., 2006. Evaluation of a year-long dispersion modelling of PM10 using the mesoscale model TAPM for Christchurch, New Zealand. Sci. Total Environ. 349: 249–59.
CAPTCHA Image