title: Atmospheric removal of PM2.5by man-made Three Northern Regions Shelter Forest in Northern China estimated using satellite retrieved PM2.5concentration.
abstract: Atmospheric removal of PM2.5by the Three Northern Regions Shelter Forest (TNRSF) - the so called Green Great Wall (GGW) in northern China through dry deposition process was estimated using a bulk big-leaf model and a vegetation collection model. Decadal trend of PM2.5dry deposition flux from 1999 to 2010 was calculated from modeled dry deposition velocity and air concentration retrieved from the satellite remote sensing. Dry deposition velocities of PM2.5calculated using the two deposition models increased in many places of the TNRSF over the last decade due to increasing vegetation coverage of the TNRSF. Both increasing deposition velocity due to forest expansion and PM2.5atmospheric level contributed to the increasing deposition flux of PM2.5. The highest atmospheric deposition flux of PM2.5was found in the Central-north region covering Beijing-Tianjin-Hebei area, followed by the Northwestern and the Northeastern regions of the TNRSF. While greater collection of PM2.5by vegetation was identified in the Northeastern region of the TNRSF due to higher forest coverage over this region, the most significant incline of the PM2.5atmospheric removal due to vegetation collection was discerned in the Central-north region because of the most rapid increase in the vegetation coverage in this region. A total mass of 2.85×107t PM2.5was estimated to be removed from the atmosphere through dry deposition process over the TNRSF from 1999 to 2010. The two deposition models simulated similar magnitude and spatial patterns of PM2.5dry deposition fluxes. Our results suggest that the TNRSF plays a moderate role in PM2.5uptake, but enhances PM2.5atmospheric removal by 30% in 2010 than in 1980.
authors.affiliation: Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China.
authors.forename: Jiao
authors.initials: J
authors.lastname: Du
authors.affiliation: Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Huang
authors.affiliation: Air Quality Research Division, Environment and Climate Change Canada, Toronto, Canada.
authors.forename: Leiming
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Gao
authors.affiliation: Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China. Electronic address: jianminma@lzu.edu.cn.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Ma
keywords: Dry deposition; Model intercomparison; Trend analysis; Vegetation collection