Abstract: The 10%, 20%, 30% and 40% gasification residues were mixed with 15% flat mushroom bran and applied to the contaminated soil in the coal mine area, and the changes in the number of microbial taxa in the soil were measured every 6 d in the unplanted state of the soil. The results showed that the numbers of bacteria, actinomycetes, fungi, Bacillus, ammonia-forming bacteria and cellulolytic bacteria in the soil showed an increasing trend with time; the numbers of various microbial taxa in the soil under the treatment of 30% gasification residue with 15% mushroom bran were at the highest in the same time Compared with other treatments under the same period, there was a significant difference （P < 0.05） in bacteria quantity, except for the treatment of 40% gasification residue with 15% mushroom bran on the 7th day. In conclusion, 30% gasification residue with 15% mushroom bran significantly increased the number of soil microorganisms.

Key words: gasification residue, flat mushroom bran, the number of microbial taxa, soil improvement