Distribution Characteristics And Correlation Of Urban Forest And Air Particulate Matter In Nanchang City

With the rapid developments of modern times and the speedy expansion from the city scale,the quality of air enviroment deteriorated decreasingly and the air quality of city got more and more attention from the public. PM10 and PM2.5 are two important indicators of measuring atmosphere quality,and there are obvious weakening effects that urban forest caused.My text based on GIS to analyse the distribution and landscape pattern of city forest in Nan Chang,based.we analysed the distribution character,influencing factors of atomospheric pollutants like PM2.5,and studied 10 typical varieties of trees' dust catching abilities in Nan Chang by a series of experiments,main results are as follows:(1)Distribution character of urban forest in Nan Chang:Nan Chang urban forest's distribution is not equal,relatively dispersive,mostly distributed in punctate or zonal way.The quantity of forest patches, the gross area,hectare,Analysed from city forest's landscape index,the mean area of every forest patch, hectare,and the average fragmentation,showed a gradually increased tendency that from the city center to the edge.(2) The mass concentration of PM2.5 and PM10 in Nanchang showed a decreased tendency year by year. Meanwhile it showed a seasonal variability: winter > autumn >spring > summer and had gradually decreased from the city center to the city edge in space.(3)The ranfall and relative humidity showed a significant negative correlation with the mass concentration of PM2.5 and PM10 during the relationship between meteorological factors and the mass concentration of PM2.5 and PM10. The urban area of forest patches and the perimeter of patches showed a significant negative correlation with the mass concentration of PM10 in the forest landscape pattern index. In addition the patch numbers,patch shape index and patch fragmentation had no correlation with the mass concentration of PM2.5 and PM10.(4)The dust capturing capacity of typical species in Nanchang City showed different significance. The dust capturing capacity of Pinus massoniana and Pinus elliottii is highest,The dust capturing capacity of Camphora officinarum and Camellia japonica is lowest. The dust capturing capacity of Conifer species is better than broad-leaved species.