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Ground measurements of trace gases and mass concentration of dust aerosols were obtained from April 19 to May 31，2007 at an integrated observational site of China (35.57N，104.08E，1965.8m above sea level)，which is about 48 km away from the centre of Lanzhou city.The site is located at the southern bank of Yellow River in Gansu rovince，northwestem China，just on the so-called China-loess Plateau with an elevation of about 1965.8 m above sea level.The instantaneous volume mixing ratios of CO，SO2，NOx and O3 are measured continuously along with the size distribution of atmospheric aerosols in the 10 nm diameter range.Average mass concentration of black carbon is alsocollected during this experiment.The light scattering coefficients measured derived from single-wavelength nephelometer for 450，520，700nm.Overall，there is a very good agreement between scattering coefficients and PM1o for the time period observations，especially during dust events.The obj ective of this study is to understand the detailed characteristics and underlying mechanisms of air pollution in Lanzhou and its potential impacts on the regional/global climate.Preliminary analysis shows that the hourly mean volume mixing ratios of O3，CO，SO2，NOx are 48.67 ppb，609.12 ppb，8.10 ppb，and 6.89 pb，respectively.During a dust storm event，the mass concentration of particulates(PM10)can rise to-2484.72ug/m<3，-13 times as high as that in non-dust storm days.Dust plumes are transported from the surface to a long distance from their sources and have a significant influenceon regional air quality in this region.The meteorological analysis indicates that these polluted layers are not from local sources.