Abstract:

 Wind erosion and dust in farmland soil release a large amount of PM₁, PM_2.5 and PM₁₀ into the air, leading to serious air pollution. In this study, a combination of field investigation and semi-fixed monitoring methods were used to measure wind speed and particulate matter concentration at different locations before and after three kinds of shelterbelts, namely tight structure (5667plant·ha⁻¹), transparent structure (3000plant·ha⁻¹) and ventilation structure (950plant·ha⁻¹). The wind-proof effect and particle reduction rate were calculated, the wind-proof effect of different structure shelterbelts was analyzed, and the particle reduction rate of shelterbelts and its influencing factors were explored. In order to optimize the structural parameters of the shelterbelt and strengthen the retarding function of the shelterbelt to PM₁, PM_2.5, PM₁₀ and other particles. The results showed that: (1) the wind protection effect at 1m height of the shelterbelt was: transparent structure shelterbelt (37.95%) > tight structure shelterbelt (32.61%) > ventilation structure shelterbelt (25.67%). The wind protection effect at 2m height of the shelterbelt was: transparent structure shelterbelt (49.66%) > ventilation structure shelterbelt (19.64%) > tight structure shelterbelt (19.38%). (2) The reduction rate of PM_2.5 in tight structure shelterbelt was −22.5%, and the reduction rate of PM₁ in transparent structure shelterbelt and ventilation structure shelterbelt was −41.36% and −18.06%, respectively. (3) Meteorological factors had the greatest influence on PM₁₀ concentration, and there was a significant positive correlation between PM_2.5 concentration and wind speed behind the forest belt (P<0.01).

Key words: Shelterbelt, Structure, Windproof efficiency, Particulate concentration