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Sea Sonal Variations of Sandstorm-aerosol Concentration Near the Ground Surface Around Minqin

Author: FengXiangDong
Tutor: ZhaoMing；WangLi
School: Gansu Agricultural University
Course: Soil and Water Conservation and Desertification Combating
Keywords: Minqin sandstorm-aerosol concentration PM10 meteorological ground cover
CLC: X513
Type: Master's thesis
Year: 2010
Downloads: 50
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Abstract

Dust aerosol is a kind of atmospheric aerosols, which is a human harming weather pattern that mainly caused by the breaking out of dust weather pattern in north China. It affects the evolution of natural environment and humankind life. Recent years, dust storm disaster in China caused a great deal of concern, studying the character of dust aerosol is the key factor to understand the bad effects of dust storm. So it is useful to have addition research this field.After the summarizing of old literature, the dust aerosol in and out Minqin oasis and deserts was studied, the character of dust aerosol was revealed by analyzing the date quantificationally and qualitatively, which is useful to design desertification control programming , bring desertification control engineering and Sand fixation into effect in theoretically and technologically.(1)After the summarizing of old literature, the dust aerosol in and out Minqin oasis and deserts was studied, the character of dust aerosol was revealed by analyzing the date quantificationally and qualitatively, which is useful to design desertification control programming , bring desertification control engineering and Sand fixation into effect in theoretically and technologically.(2)The regulation of aerosol in sunny day of oasis is that the concentration of PM10 aerosol at 1 m high is strong relative to temperature because of effecting by sun radiation;the concentration of PM10 at 25m high is relatively stability;the concentration of PM10 at 50m is direct proportion to wind velocity(3)The condition of underlying surface is the main factor that affect the procession of dust storm, whose difference affect the concentration of aerosol PM10 . the statistics analysis of dust aerosol in minqin ,adjacent oasis and oasis which have different underlying surface condition indicated that the concentration will declining from deserts to oasis, and the average value was 1.667 mg/m3 in desert underlying surface , 1.204 mg/m3 in adjacent oasis and only 0.878mg/m3 in oasis.(4)The ground condition is bare in spring,which ground roughness is low and the concentration of is the highest; The ground roughness is increasing in summer dramatically , whose aerosol concentration is lower; The ground roughness is declining in winter,whose aerosol concentration is increasing. The change of roughness in season is relative to the concentration of dust aerosol, but the trend is not distinctive which is affect by atmosphere circulation.(5)The PM10 and TSP is changing with season, the PM10 and TSP is the highest in spring ,where there is a great number of coarse granularity ;the value of PM10 and TSP is declining in summer and autumn, whose value is the lowest in autumn; the total of PM10 and TSP is increasing because the east Asia monsoon act and the ground granularity is blow and the main aerosol is bulky grain.

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