Dust Particle Distribution and Physical Characteristics over Hunshan Dake Sand-land during Spring

The physical characteristics of dust aerosol were collected over Zhurihe (ZH) site, which lies on the southwest border of Hunshan Dake sand-land (YIDS), by using WPS (Wide-Range Particle Spectrometer) model 1000XP during the spring of 2006. Size distributions of particles with 0.5-10.0 mu m were examined and the daily mean number concentration of aerosols for the situ periods on non-dusty days was 86.7cm(-3). It was 1333.08cm(-3) on windblown dust (WD), 2817.09cm(-3) on light dust storm (LDS) and 4372.58cm(-3) on severe dust storm (SDS). Comparing with Sanggen Dalai (SD), which lies in the inner of HDS, observed during IMGRASS (Inner -Mongolia Semi-Arid Grass-land Atmosphere Surface Study) of 2001, the average number concentrations of dust aerosol was 3039.5cm(-3) on SDS, 659.7cm(-3) on LDS, 198.3 cm(-3) on WD and 27.7 cm(-3) on ND of the inner HDS. The results show that there are more dust aerosols over the board than the inners both on dusty days and non-dusty days, but the mean particles diameter over the inner is larger than the boards.