Abstract: Due to its small size and inertia tendency of sedimentation, fine particulate matter (PM_2.5) seriously pollutes the environment, while vegetation can alleviate the pollution from particulate matters to a certain extent. Based on the previous studies on the sedimentation mechanisms of PM_2.5, this paper analyzed the interactions between PM2.5 and vegetation. Through blockage and adsorption, vegetation can positively remove atmospheric particulates, whereas the retention of excessive particulates can negatively affect plant growth. However, the positive effect of vegetation on atmospheric particulates is overweighed the negative effect. This paper elaborated the effects of vegetation crown, stem, and blade on the removal of PM_2.5 at the scales of forest stand (environment features), individual tree (tree species characteristics), and blade sample (types and distribution of particulates), and with the considerations of environmental factors (meteorological and aerodynamical elements, atmospheric particle concentration, and plant phenology), air chamber experiment, and characteristics of particulates retained by blade. It was suggested that in the further researches, quantitative measurement should be preferred, with the focuses on the comparative analysis and systematic study about the PM_2.5 removal capability of different kinds of vegetation and on the determination of dominant tree species for the prevention of atmospheric PM_2.5 pollution in a certain place.

Key words: Mu Us desert-loess plateau transition zone, spatial heterogeneity, soil salinization, influencing factors.