Method for artificially strengthening natural attenuation of polycyclic aromatic hydrocarbon in soil

The invention discloses a method for artificially strengthening natural attenuation of polycyclic aromatic hydrocarbons in soil, which comprises the following steps: mixing a high-efficiency degradation flora with an inorganic salt culture solution, and adding the mixture into soil polluted by polycyclic aromatic hydrocarbons, the high-efficiency anaerobic degradation flora being a mixed flora taking pseudomonas nitroreducens as a dominant strain; then adding a potassium nitrate solution with a certain concentration into the soil, and uniformly stirring and mixing with the soil; the surface of the soil is sealed, an anoxic or anaerobic environment is kept, and biological stimulation and biological enhancement natural degradation are carried out; and regularly supplementing the potassium nitrate solution with the same concentration into the soil, and stopping degradation when the degradation rates of the polycyclic aromatic hydrocarbons phenanthrene and pyrene in the soil respectively meet the requirements. Ac