Effect of Vegetation Coverage on the Dust Weather in Inner Mongolia

The typical dust behavior in Inner Mongolia with different vegetation coverages was simulated using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) and sensitive tests. The influence of vegetation coverage on the evolution of the dust weather intensity and long-distance dust movement was investigated. The results show that WRF-Chem can better reproduce actual dust movement. Moreover, the sensitivity experiments with different vegetation coverages reduced 50% of the total dust when the vegetation coverage of the sand source was increased by 5%. Additionally, the reduction of the surface dust concentration, including PM₁₀ and PM_2.5, in the downstream area was over or nearly 80%. The air quality improved from severe to light pollution, demonstrating effective atmospheric environment improvement. When the vegetation coverage was increased by 15% or more, the contributionto the sand emission flux of the large-grained sand particles gradually increased, and the sedimentation rate increased during dust transportation, increasing the peak dust concentration at downstream areas. As the vegetation coverage increased, the leaf area index increased, and the vegetation’s capture effect of fine particles was enhanced. Thus, it can be concluded that desertification control projects, such as afforestation, should first be performed in partially deserted areas with fine dust particles.