Dust storms, dust transfer and depositions in the southern Aral Sea region

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1 Dust storms, dust transfer and depositions in the southern Aral Sea region Aslanov, Ilkhomjon Author s Affiliations and contact: *Philipps Unversität Marbug Faculty of Geography PhD student Deutschhause str 10 Phone ilhomaslanov@gmail.com Paper prepared for presentation at the Young Researchers Forum of the International Conference- Natural Resource Use in Central Asia: Institutional Challenges and the Contribution of Capacity Building September 30 to October 1, 2013 JLU, Giessen, Germany Copyright 2013 by [Ilkhomjon Aslanov]. All rights reserved. Readers may make verbatim copies of this document for non-commercial purposes by any means, provided that this copyright notice appears on all such copies. 1

2 Dust storms, dust transfer and depositions in the southern Aral Sea region Introduction Aeolian processes as manifested by dust and sand storms (DSS) are natural events that occur world-widely in arid regions (Orlovsky et al 2009). The vast distribution and existence of desert landscapes indicates that these regions are a very important source of dust storms in historical time but in more recent times the action of humans has created another source on the desert margins in semi-arid areas that previously were stable (Youlin et al 2001). Dust storms are the type of natural disaster which is most likely to occur in arid and semiarid regions in the world, such as central and eastern Asia, the Sahara Desert and some regions in Australia, North America and elsewhere. It is believed that there are two major factors which influence dust storm formation: one is the surface conditions which have been identified to play an important role in sand and dust material source in the deserts and poorly vegetated areas in the world (Sun&Zhao 2008). High solar radiation and evaporation, high risks due to wind and water erosion caused by the above mentioned relief and soil conditions, high mineralization of both surface water and ground water, the scarce vegetation cover as well as the nearly year round deficit of soil moisture all are natural factors for desertification is such a crucial factor (Opp 2005). Although Asian dust s significant environmental and social impacts during its transport process has stimulated a concerted research effort to better understand its transportation characteristics, progress in understanding dust transport from individual key dust source areas has remained limited. Dust transport also has considerable impact on human society if highly populated regions are on the transport pathway. Dust transport can bring pollutants into residence areas (Gao &Washington 2010). The quantitative prediction of dust storms is impossible unless the entire dust cycle, consisting of dust emission, transport and deposition, can be correctly predicted. In recent years, dust emission schemes have been developed that account reasonably well for the impacts of atmospheric forcing and land-surface properties on dust emission (Sun&Zhao 2008). An area's potential for dust storm generation is related to its climate (its precipitation patterns, prevailing wind direction and speed, and normal location of low- and high- pressure centres). The world s arid desert and semi-arid climate zones correlate with the 2

3 major deserts. Sand and dust storms are frequent in Central Asia because of semi-arid areas. (Groll et al 2009). Research area and map!!! (Fig.1) Research area Stations Fig. 1 The main factors of dust storms rise are recurrence of strong winds and vast area of dust emission sites, where the latter is the subject of change. During the last decades owing to the crisis situation in the Aral region the total area of dust emission sites increased significantly because of the shrinking of the Aral Sea and consequent drying of its exposed bottom and deltaic areas of Amudarya and Syrdarya Rivers (Orlovsky et al 2004). Problem settings and Objectives The Aral Sea problem has formed by the relations between humanity and nature and human attitude without affection by seeking to development to the environment. During the one generation life the Aral Sea had already dried and there is a desert instead of it. Under conditions of the Aral Sea ecological crisis, natural ecosystems within a 400 km radius of the seashore have undergone transformations. In region of Aral Sea crisis cause many problems depends and affects each other (Fig. 2). 3

4 Shrinking of Aral Sea (lake) Health issues Desertification Dust storms and dust transfer ECOLOGICAL PROBLEMS Salinization Effects on climate Water problem Ground water table reduction Fig.2 In my research I point out one problem in this region dust storms and dust transfer. The aim of this research approach is to analyses spatial and temporal distribution of dust deposition in the southern Aral Sea region. Dust occurrence and its effects lead to the modification of the mineral structures of the arable land. Productive soils are degraded and salinized the agricultural productivity is decreasing. study the influence of negative chemical elements in soil Materials and methods The spatial and temporal distribution of the dust deposition was analyzed using passive deposition sampler installed in 7 stations in the region. The sampler design was longevity required for long-term measurement program. Each sampler consists of a plastic tray (diameter 23cm) as dust and sand sink, filled with artificial grass. (Fig. 3) A soil sample was collected in field work 2011, in 6 stations. It was taken 3 soil levels (Fig.4). Meteorological data s collected 7 stations include temperature, precipitation, wind direction, wind speed and dust storms. 4

5 Fig.3 Fig.4 The dust samples were weighed using a precision scale with an accuracy of g. the grain size distribution was analyzed by means of microscopic grain size counts (analyzing for representative subsamples per dust sample using 0.2 g of sample material). Results and conclusion An analysis by sampling station reveals much more Deposition of dust. Average dust deposition in Buzubay was around 1000 kg per hector in year around and there are more effect Kyzylkum. On the other hand, other 3 stations were more affected by Aralkum (Drybed). The most distribution of dust lasts 7 month (April to October) in a year. (Fig. 7) 5 Fig. 7

6 The grand size distribution of the collected dust samples are also very different in Buzubay station (75 % medium silt ( mm) and other 3 stations were more effected by Aralkum. Jaslyk 55 % coarse, medium, fine sand ( mm), Muynak 50 % coarse, medium, sand ( mm), Takhiatash 68 % coarse, medium, fine sand ( mm). The results from the chemical analysis of the dust samples revealed 4 major elements HCO3, SO4, Cl and Ca. There are not big differences between stations. However, Buzubay main chemical element is HCO3, other 3 station are Cl and SO4, which means Muynak, Jaslyk and Takhiatash stations were mostly affected from Aralkum. References. 1. Ataniyazova. A. Health and Ecological Consequences of the Aral Sea Crisis. //The 3rd World Water Forum Regional Cooperation in Shared Water Resources in Central Asia Kyoto, March 18, Otajonov I.SH. Ecological situation Priaral region and it s social effect s.//socialeconomic problems Priaral region and this geographic resolve. Urgench Semyonov O.E. Falling of sandy salty aerosol on the surface of the Priaral region. Problems of desert development 3-4, Opp Ch. Desertification in Uzbekistan//Geographische randschau. Vol. 1, No. 2/ Esanov P., Amanov A. Soil ecological monitoring in Aral sea basin. // Problems of desert development. International magazine No Ashgabat. 6. Arnagel dyev A.A., Kostuykovsky V.I. Eolian processes in the Aral sea Basin. // Problems of desert development 3, Babaev A.M., Breburda J. Mapping desertification monitoring in Turkmanistan// Problems of desert development 3, Izrail Yu. A., Anokhim Yu.A. Monitoring of ecological climatic changes in the Aral Sea Basin. Problems of desert development 3-4, Gao H. and Washington R. Transport trajectories of dust originating from the Tarim Basin, China.// Int. J. Climatol. 30: