The Study On The Observation Of Dynamic And Thermal Parameters Of Surface Sand In The Hinterland Of Taklimakan Desert

In this paper,based on the meteorological data including wind,temperature，soilmoisture and so on and the sand transport data gained from the station ofatmospheric environment experiment and BSNE sand trap in Tazhong area,andcombined the parameters of vegetation and surface soil particle size, Criticalthreshold sand—moving wind speed, drift potential，sand flow structure，the dustflux and surface heating flux have been systematic researched.The preliminaryresults are as follows:（1）The annual average wind speed was around2m·s^-1and showed therelatively stable;The months average wind speed showed unimodal distribution,themaximum value appeared in the June or July.The wind direction and sand-movingwind direction was E，NE，ENE.The days of blowing sand was increasing whilesandstorm was reducing.（2） The monthly fluid critical threshold sand moving wind speed of sand inTazhong area was between0.24m·s^-1and0.36m·s^-1; the max accoured in July andAugust,the min accoured in May,and the monthly threshold sand—moving windspeed was between3.9m·s^-1and5.9m·s^-1, it’s seasonal distribution was summer＞winter＞autumn＞spring, the yearly threshold sand—moving wind speed was5.1m·s^-1.（3） The annual average drift potential from2006a to2012a was227.4VU,theresultant drift potential was136.6VU, the resultant drift direct was51.83°.theRDP/DP was0.6.The drift potential mainly appeard from March to August.The driftpotential was206.4VU, it accounted for90.59%of all year. the resultant driftpotential was123.3VU, the resultant drift direct was50.25°.The resultant driftpotential was the most in spring,which was123.7VU,the secondly wassummer,which was82.3VU，and the least was in winter,which was only1.1VU.（4）The dust flux was well decribed in power function,the Correlation coefficient was all greater than0.9. About90%of the dust flux transported within50cm,whenthe height reach to75cm,more than95%of the dust flux transported,the total dustflux from the section which was100cm×100cm was4.8kg,The monthly average ofthe dust flux was0.4kg, which from the October of2011to September of2012.Theaverage of the dust flux was0.8kg, in spring and summer, and was0.03kg in autumnand winter. The fronter was almost26more than the banker.From0to200cm,Correlation coefficient of vertical distribution of horizontal aeolian flux of differentunderlying surface in Tazhong，fitted by power equation,these two underlyingsurface condition differ by up to1.7times,which througth the same section,the top ofdunes level of dust flux distribution curve moderate sediment flux with a high digreeof decline rate which is less than the sandy ground.（5）In this area,the monthly surface sensible heating flux showed a single peak,whichappeared from May to July;analysis different weather conditons:Sunday,dust,blowingsand and sandstorm,we can find: sandstorm＞blowing＞sand dust＞Sunday;before12h of the sandstorm, analysis the surface sensible heating flux, the maximumwhich contribute to the sandstorm is in summer, the minimum is in winter;the surfacesensible heating flux and the occurred days of dust weather have a positivecorrelation ship.