Indication and response of soil microbe to acetochlor

An experiment was conducted to determine the effect of acetochlor (a soil pollutant) on soil microbe and soil microbial biomass carbon. Then the potential of soil microbe and microbial biomass carbon as indicators for acetochlor pollution in soil was analyzed. The results show that soil microbe is inhibited by short-term acetochlor application, but it recovers over the long-run due to the acetochlor degradaton. During inhibition, the number of bacteria, actinomycete and microbial biomass carbon content exhibit negative linear correlation with the log of acetochlor concentration. On the 7th day, the correlation between the log of acetochlor concentration and bacteria and actinomycete are expressed in the respective equations as y = -2.97x + 12.36, R² = 0.999 3; and y = -2.13x + 6.67, R² = 0.956 4. For microbial biomass carbon, the correlation equation on 14th day is y = -89.25x + 348.90, R² = 0.995 4; which are all significant. However, the effect of acetochlor on fungi is insignificant and hardly noticeable. Hence soil bacteria, actinomycete number and microbial biomass carbon content can be as good indicators for soil pollution by acetochlor in the short-run.