Effects of roxarsone expo to carbon-source metabolic capacity and functional diversity of soil microbial communities

【Objective】 To evaluate the effects of roxarsone residues on the microbiological characteristics of soil, the carbon-source metabolic functions of the soil microbial communities exposed to roxarsone and studied by Biolog technology.【Method】 Fresh soil with different concentrations of roxarsone solution mix were collected so that drugs were (as As): group 15 mg·kg^-1, group 75 mg·kg^-1, group 150 mg·kg^-1, cultivated at room temperature (20-25 ℃). Soil samples were taken after 1,2,3,5,8 weeks of treatment for analysis using Biolog method.【Result and conclusion】 The results showed that the carbon-source metabolic functions of the soil microbial communities of groups treated with roxarsone were significantly distinguished from that of CK, indicating a dose-dependent relationship. The carbon-source metabolic functional diversity of soil microbial communities in the lower roxarsone groups (w=15 mg·kg^-1) were not significantly different from the control group during the 1st week. However, the soil microbial community functional diversity in the four groups (control, low, medium and high group) was significantly different in the 2nd, 3rd, 5th and 8th week. The difference between control and treatment groups appeared to be much more severe with the increase of roxarsone concentration. It is concluded that the carbon-source metabolic capacity and functional diversity of soil microorganisms in roxarsone treatment groups change with the increase of roxarsone concentration. In the 2nd week and 3rd week, the functional diversity of the soil microbial community of the three roxarsone groups decrease more rapidly compared with that in the 5th week and 8th week, which might be caused by the chemical conversion and degradation of roxarsone in soil.