| The surface layer, whose atmosphere quality would directly affect people’s health, was regarded as the main space for people inhabiting. Thus, the research on surface layer’s ozone and nitrogen concentration appeared increasingly significant. It is necessary to study the variation regular upon ozone and nitrogen oxide concentration for revealing the change ozone and nitrogen concentration and providing scientific proof to air pollution prevention.In Shaanxi normal university Chang’an campus in Guodu town of Xi’an, we observed the ozone and nitrogen oxide concentration and meteorological factors in 52m height range in day and night for three times in October 2014 with the help of,portable instrument, we analysis the temporal and spatial change of ozone and nitrogen concentration, and revealed the effect of meteorological factors on both the concentration variation. The main conclusions were as follows:(1) Though three times day and night observation on ozone concentration in Guodu town of Xi’an in October 2014, we found that diurnal variation of ozoneconcentration at 1-52m was similar, which appeared single-peak distribution, all peak reached at 14:00, the difference of diurnal ozone concentration was large. The diurnal variation of ozone concentration could be divided into three stages. The first stage was 0:00-8:00, this ozone concentration in this stage was lowest. The second stage is 10:00-16:00, the ozone concentration in this stage was highest. The third stage is 18:00-0:00, this stage was the middle stage.(2) The diurnal variation of nitrogen oxide concentration in Guodu town of Xi’an in October 2014could also be divided into three stages,0:00～8:00 was the first stage, which was the lowest stage. The second stage was 10:00～16:00, and was the highest concentration stage. The third stage appeared at 18:00～22:00, this stage was the middle stage.(3) Through the analys is about vertical variation of ozoneconcentration in October 2014, the vertical variation of ozoneconcentration could be divided into two types. The first type appeared at 8:00-18:00, the main characteristic is that ozone showed a increase trend at the height of 1～10m, the he ozone concentration was a decreasing trend at the height of 13-22m, However, the ozone concentration was constantly increased as altitude increased at the height of 25-52m. The second type started from 20:00 to 6:00, main characteristic was that the concentration increased with altitude increasing at the height of 1～10m, the ozone concentration variation had a opposite trend at the height of 13-52m.(4) Depending the vertical variation of nitrogen oxide concentration in October 2014, we could divide the change into three types in this study. The first type appeared at 12:00～16:00 and 0:00～4:00, at the height of 1～43m, the nitrogen oxide concentration change had a increase trend, variation of nitrogen oxide concentration had a contrary trendas with the height increase at the height of 46-52m. The second type started from 18:00 to 22:00, the increase trend wasn’t obvious at the height of 1～43m, the opposite trend appeared at the height of 46-52m. The thirst type appeared 6:00～10:00, at the height of 1～31m and 46-52m, nitrogen oxide concentration had a decline trend, he ozone concentration variation had a opposite trend at the height of 33-43m.(5) Ozone concentration, which observed in research zone in October 2014, was negatively correlated with nitrogen oxide concentration, temperature, relative humidity and wind speed. And it was positively correlated with air pressure, sun radiation and mixing heights.Nitrogen oxide concentration was positively correlated with temperature and mixing heights, and was negatively correlated with wind speed, relative humidity, air pressure and sun radiation.(6) The research area wasn’t polluted by ozone in October 2014, but the serious pollution phenomena about nitrogen oxide occurred in 12:00～16:00.(7) During the period of observation, the main remote source comes from areas that were sparsely populated,drier climatic condition and lower vegetation coverage. |
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