Method for identifying urban natural air duct according to natural environment

The invention discloses a method for identifying an urban natural air duct according to a natural environment, and the method comprises the steps: building a research region, and building a terrain grid according to a digital elevation model (DEM) of the region and a high-resolution remote sensing image; taking the terrain grid as a calculation airspace, calculating a near-earth steady-state windfield under a specified main wind guide condition by utilizing a wind field simulation calculation model, deducing a wind advancing route penetrating through the whole research area according to a wind direction vector field, and expressing the wind advancing route in a dense flow force line form; and superposing the hydrodynamic line graph and the remote sensing image layer together, and selecting the hydrodynamic line which is most beneficial to feeding high-quality air into and penetrating through the urban area as the optimal natural air duct in combination with the distribution conditionsof the oxygen source area