Beijing City Relationship Between Respirable Particulate Matter Distribution And Land Cover Types

Nowadays, inhalable particulate matter is becoming major pollutant in the air of cities. It has important influence on human health and atmospheric visibility, so more and more people are paying attention to it. Western countries started the research on inhalable particulate matter earlier. Recent years, China has also already started the research on it, and has got a certain achievements, but macroscopic monitoring of inhalable particulate matter by remote sensing method has not yet formed a complete system.Beijing urban is taken as study area in this paper. Landsat TM and SPOT-5 images are used to do retrieval research on inhalable particulate matter, and the correlation between inhalable particulate matter and land cover is analyzed. Main research contents are as follows:(1) TM images from 2007 to 2009 year are used to extract Difference Vegetation Index (DVI), the correlation between inhalable particulate matter and DVI is analyzed, combined with simultaneous monitoring inhalable particulate matter data, and regression equations are established to do retrieval experiment. In the retrieval results, concentration of inhalable particulate matter is lower near vegetation, and it is higher around building area. The errors of 2007-2009 year retrieval results are 20.588%, 25.180% and 10.798%. Aerosol Optical Depth (AOD) is extract from TM image of 2009 year, and it is used to build a regression equation with inhalable particulate matter data. Then distribution of inhalable particulate matter is retrieved with the regression equation. The error of retrieval result is 15.606%.(2) The retrieval results and the boundary of every district in Beijing urban are used to count concentration of inhalable particulate matter in every district. The trend of inhalable particulate matter distribution is basically identical in every district from 2007 to 2009 year. Concentrations of inhalable particulate matter in Xicheng district and Dongcheng district are the highest, and it is the lowest in Haidian district and Shijingshan district. During the three years, concentration in 2008 year is the lowest, and it is highest in 2009 year.(3) Ten sampling cites are selected from all the sampling cites in 2007 year. As the experimental areas, the radius of 0.5km and lkm of the ten sampling cites are taken from SPOT-5 image in 2007 year. Object oriented method is used to extract the land cover types, and Vegetation Coverage Rate (VCR) is calculated. The relationship between land cover and inhalable particulate matter is analyzed. There is a negative correlation between VCR, vegetation and inhalable particulate matter, and a positive correlation between building area and inhalable particulate matter. The correlation coefficient between building area and inhalable particulate matter is higher than that between VCR, vegetation and inhalable particulate matter. The correlation coefficient in 0.5km experimental area is higher than that in lkm experimental area.The research contents and conclusions above can provide some meaningful reference comments for air pollution controlling in Beijing urban, and are also meaningful for the researches in other areas.