The specific wind of arid and semi-arid areas that caused creating the dense cloud of dust to height about 3000 meters is called dust storm. The density of this dusty cloud (about 4000 ton dust per each cubic kilometers of air) is too much that could block the view completely [1] . Wind separates fine particles from the surface in three ways:

1) Suspend state covers the particles with diameter less than or equal 100 micron included 3% - 38% of all cases.

2) Swirl moves the particles larger than 100 and smaller 500 micron in diameter included 55% - 75% of all cases.

3) Rolling motion rotates the particles larger than 500 and smaller or equal 2000 micron in diameter. This covers 7% - 25% of all cases.

But the World Meteorological Organization (WMO) provided following definitions to haze events that included removal of fine particles from the land surface [2] :

a) Dust storm as a result of turbulent flow and wind turbulence transmitted lots haze (mainly Silt and Clay) to air and the visibility reduced to less than 1000 meters.

b) Blowing dust occurred by wind blowing to a considerable height above ground and caused visibility reduction between 1 and 2 kilometers (without air turbulence).

c) Dust haze is created by the suspended haze. This haze separates from ground before dust storm occurrence.

d) Dust devils as a result of hurricane wander high columns of haze. Their height could reach to 300 meters or more.

Identification of regimes tend to haze produce may determine using satellite data. Most of dust storms clearly are seen in limited areas. Global distribution of dust storm study provided ring of dust. These rings mainly extended in northern hemisphere from north of Africa to China and outside of this ring dust density is reduced. In fact dust creation could be typical respond to vegetation changes [3] . Dust usually impacts on the human activities and the environment such as cloud formation and properties and rainfall, visibility reduction, increasing temperature, degradation of air quality, diseases transmission, and breathing problems. Atmospheric dust prevents sunlight penetration and may cause decline in agriculture production to 5% - 30% [4] . Dust transmission in the atmosphere and entering them into sea cause logging toxic and heavy metals on the seas [5] . Also dusts may have microorganisms like bacteria and fungi or degradation organism resistance chemical compounds. They could cause disease by creating larvae and toxic compound [6] . Pterygium and sandy keratitis are among the common diseases caused by haze. Sand particles also may cause scratched cornea and reducing visibility [7] .

Dust storms blow in about 21% area of Iran. The most important dust resources are from Syrian Desert, north of Arabian Peninsula desert and south of Iraq deserts that imported into the west Country. The number of stormy days only in Khuzestan is more than 15 days in a year [8] . Dry bed of Hamun Puzak is the most important solid particles of storms power supply in southeast of Iran. High temperature s during 120 days wind blowing and cassation of the rainfall and physical drought of the environment provided appropriate conditions to blowing dust storms [9] . The areas where are the rich Silt is responsible of the most haze storms because the adherence between the particles of Silt soil is low inherently also since no interlock between particles in result of relatively large rounded slid on each other and transmitted by water and wind. To avoid Silt motion and movement should increase friction and engagement between soil grains or adherence between the particles. Many factors included type of soil, topography, and climate could make a prone area for haze creation. Among these changing soil properties by additives considered a factor for controlling haze. Using adhesive materials like cement, lime, tar, yarn, and slag can solve weak point of these soils largely [10] . Cement and lime used for soil stabilization from many years ago. Tar jointed to stabilizers after oil exploration. Tensile strength is the main property of the yarn that resulted in increasing soil tensile strength. Root of plants as a yarn could cause significant increase in soil stabilization and consolidation [11] . Slag is a pozzolanic material that could use to soil stabilization [12] and [13] . Continuous spraying water on the soil bed is one of common approaches to avoid soil erosion however could be quick costly depending on the climate of design area and requirement labor [14] . From 1980 soil stabilization by polymer got more importance than old stabilizer because of simple implementation and high perform speed and creating high strength [15] and [16] . According to different features of these chemical materials they used with different goals and forms to increase holding capacity of the soil and controlling wind and water erosion [17] . Therefore in this study effect of Poly vinyl acetate polymer as stabilizer factor of haze studied.

In the conducted study soils of south areas of Sabzevar and Emulsion Poly vinyl acetate polymer had been used. It was done in soil mechanics laboratory and wind tunnel of Hakim university of Sabzevar.

We knew that adding polymer to soil increase its adherence. Therefore we must can obtain this adherence. It obtained with soil mechanics laboratory tests. To start and preparation suspension the specific amount of polymer powder combined with 50% weight of water. Provided suspension added to the silt soil with different

coefficients to achieve the best dose to the soil stabilization. The suspension concentrations started from without polymerto 30 grams polymer per square meter, with increasing 5 grams polymer/squared meter relative to last state.

1) Despite dry specific weight of soil reduction by adding polymer wind resistance of samples increased.

2) By compressing tested soil, with and without polymer, the strength of soil is increased.

3) This idea that adding polymer to soil almost 3 hours after mixing when setting didn’t occur and resistance of soil didn’t change has no effect isn’t correct.

4) Since the wet samples have better wind resistance and remain stable.

5) In general wind resistance of soil increased by increasing polymer concentration.

6) The best value of this polymer for stability against wind can be almost 20 - 30 gr/m².

7) It suggested that to optimization operating conditions the test had been done in desert scale and used polymer concentration in natural condition determined by considering others important parameters like temperature, moisture, direction and speed of wind, the vegetation, permeability coefficient of soil, influence of polymer, performance and sprinkle, the density and etc.

Thanks to our cooperator in wind tunnel laboratory for his unsparing assistance at Hakim Sabzevari University.

GholamrezaTadayonfar,NargesShahmiri,Mohammad HassanBazoobandi, (2016) The Effect of Polyvinyl Acetate Polymer on Reducing Dust in Arid and Semiarid Areas. Open Journal of Ecology,06,176-183. doi: 10.4236/oje.2016.64018