Flux evaluation method and system suitable for near-ground unorganized emission source

The invention provides a flux evaluation method and system suitable for a near-ground unorganized emission source. The flux evaluation method comprises the following steps: (1) arranging monitoring equipment to carry out real-time gas emission data monitoring; monitoring point positions are arranged in the park in a gridding point distribution mode; (2) evaluating the greenhouse gas emission flux of the unorganized emission source; a near-ground point source diffusion Gaussian calculation formula is given, after logarithms of the calculation formula are taken, all items on the right side of the calculation formula are directly measured by monitoring equipment arranged in a gridding mode, and then the emission flux of the unorganized emission sources in the park is obtained. On the basis of the Gaussian diffusion model, the source intensity back calculation model for the unknown diffusion mechanism is provided, flux evaluation of the near-ground unorganized emission source can be achieved only by adopting grid