Response of PM2.5 pollution to land use in China

As the spatial carrier of the emission sources and influencing factors of PM2.5, land use and its changes can inevitably affect local and regional PM2.5 concentrations. The relationship between the growth of PM2.5 and the changes of land use in China during 1998-2015 was explored in this paper using the Theil-Sen median trend analysis, Mann-Kendall and spatial econometric model. The results showed that the area where PM(2.5 )concentration was less than 10 mu g/m(3) accounted for a small portion (18.33%) of the land area in China, and the area where PM2.5 concentration was more than 35 mu g/m(3) accounted for 31.30% of the land area. High PM2.5 concentration was found in the East China Plain and Taklimakan desert; artificial surfaces, cultivated land and deserts were coated with high PM2.5 concentration more frequently, while the forest, grassland and unused land were usually covered with low PM2.5 concentration. PM(2.5 )concentration in desert land and artificial surfaces respectively increased at a pace of 1.07 mu g/m(3) and 0.80 mu g/m(3) per year during 1998-2015, higher than those in other land use types. They mainly came from the sand dust aerosol in northwest China, while those in the other areas mainly came from emissions in the human activities. Therefore, reasonable coordinating the proportion of construction land, cultivated land, forest land and grassland in eastern China, and strengthening desert governance in northwest China, are suggested to reduce PM2.5 concentration in China. (C) 2019 Elsevier Ltd. All rights reserved.