| In recent years, Beijing has faced serious air pollution problems, which has seriously threatened human health and caused widespread concern. At present, in Beijing area, there are some shortcomings in the study of the particulate matter, such as the observation point, the time is short and so on. This study by statistics in January 2013 2014 in December of Beijing area 35 automatic air quality monitoring station of PM2.5 concentration data of monthly mean values and quarterly average, with spatial information can be obtained more typical Beijing PM2.5 temporal distribution characteristics. Results showed that:(1) from the point of view of the variation characteristics of PM2.5 concentration time, PM2.5 concentration may mean a wave type distribution, and analysis of the mean season results show concentration levels in winter was highest in summer minimum, PM2.5 concentration with the season regular changes. (2) from the spatial distribution of PM2.5 concentration, the southeast of the most serious, the northwest of the lightest, the degree of pollution from south to North in order to decrease. (3) the spatial and temporal distribution characteristics of PM2.5 concentration showed that the difference of spatial distribution was more obvious due to the increase of seasonal concentration, and the difference of time distribution was more obvious due to the increase of regional concentration.Based on monitoring data of PM2.5 and PM10and ground meteorological data from January 2013 to December 2014 in Beijing, the influence of meteorological conditions on concentration levels of PM2.5 and PMiowith different size ranges was investigated for four seasons using non - parameter statistical analysis such as Spearman correlation matrix. The results showed that the seasonal characteristics of atmospheric particulate matter concentration in Beijing area were obvious, the atmospheric particulate matter was the most serious in winter, and the lightest in summer.PM2.5 and PM10 were significantly correlated with one or more meteorological parameters in different seasons, the sunlight and wind as the main influencing factors. The concentrations of both fine particles (PM2.5) and inhalable particles (PM10) were influenced by meteorological conditions, but to different extents. The PM2.5/PM10 ratio was the highest in winter and the lowest in spring. These conclusions can provide guidance for the development of scientific and effective air pollution control strategies.By two TM images of 2005 and 2013, after translation, supervised classification and vectorization operation by visual solutions, get map type of land use in 2005 and 2013 in Beijing area, area of each land use type statistics. Distribution is derived using the inversion of PM2.5 concentration space diagram and 2013 land use type map of grid operation, statistics within each mesh PM2.5 concentration and various types of land area, PM2.5 concentration and six kinds of land using non parametric correlation analysis between types. The results show that:(1) 2005 and 2013, Beijing urban and rural areas, industrial and residential land area significantly increased the 1351.57 square kilometers, up to 4013.14 square kilometers, other types of land use type area was reduced, the cultivated land area reduced most, urban development rapidly and the pace of urbanization process is very rapid.(2) there was a significant correlation between PM2.5 concentration and cultivated land area, forest land area, urban and rural industrial and mining area, and no correlation with grassland area, water area and unused land area. Which PM2.5 concentration and cultivated land area, urban and rural industrial and residential land area showed a significant positive correlation, indicating that the PM2.5 concentrations with the area of arable land, urban and rural industrial and residential land area increase and increase, with an area of woodland was significantly negative correlation, indicating that the PM2.5 concentration increases with forest area reduced, so urban planners should rational planning of land utilization, control of land and the urban and rural industrial and residential land use scale, to increase the forest area, in order to reduce the concentration of PM2.5.By 2013 March 2014 in February in Beijing PM2.5 concentration data and the corresponding period of aerosol optical thickness data were analyzed by correlation analysis. The results show that:(1) aerosol optical thickness of daily and monthly change range are larger, and summer half year, the AOD values above the level of the winter half year; AOD has obvious seasonal variations, a spring season mean highest in summer and autumn winter significantly reduced. This is mainly due to the typical climate of Beijing influence led, spring dust and other extreme weather, rainy summer, foggy autumn, the AOD values are relatively high, and winter surface reflectivity is higher, resulting in AOD values is low or absent.(2) the correlation analysis of PM2.5 concentration and aerosol optical thickness in different seasons was adopted by the correlation analysis, which showed that the correlation between AOD concentration and aerosol optical thickness was significant. PM2.5 concentration and aerosol optical thickness in the spring has a good linear relationship, R2= 0.549, get the relation equation of the two: y=20.03x+103.8.(3) according to the April 2013 in Beijing aerosol optical thickness of monthly mean spatial distribution figure and PM2.5 concentration and aerosol optical thickness relation equation of PM2.5 concentration spatial distribution map in the inversion, inversion of PM2.5 concentration spatial distribution is "North South high - low" state, in line with the actual situation, indicating that the inversion effect, and can be used for the relation type data preparation is discussed below and land use.Beijing is currently facing serious air pollution problems, which damages human health, and it has aroused people’s wide attention. At present, there are some shortcomings in the research of PM2.5 in Beijing, such as the observation point is less, the time scale is short and so on. This study collects the monthly and quarterly PM2.5 data from 35 automatic air quality monitoring stations in Beijing during the period of 2013 -2014. Combined with spatial information, we can obtain more representative spatial and temporal distribution characteristics of PM2.5 in Beijing. Based on the 2920 tiles MODIS/NDVI images of 2013 January to 2014 December in Beijing, and by using the method of Local Maximum Filtting and calculated the vegetation coverage from NDVI. Then this study conducted the regression analysis based on the data of PM2.5 and vegetation coverage in 2013 and 2014,and obtained the spatial distribution of vegetation coverage in Beijing and its surrounding areas in 2013 and 2014, and compared the changed area of vegetation cover in Beijing that aim to illustrate the relationship between the PM2.5 and vegetation coverage. The results showed that:(l) got the regression equation of the relationship between the two, and found that the correlation between the two is very high.(2) the increase of vegetation area has a positive effect on the decrease of PM2.5 concentration. These conclusions will provide an important scientific basis for air pollution control and environmental protection in Beijing. |
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