Microbiological Monitoring And Evaluation Of Compound Pollution Of Peroleum And Heavy Metal In Salted Soils

Petroleum and heavy metal which are typical soil environmental pollutants often exist simultaneously and distribute widely in salted soils. By strengthening petroleum-heavy metals contamination studies,we can evaluat the migration of pollutants transformation behavior under the combined pollution in salted soils properly. And we can get important theoretical significance and technological support from solving the problem of environmental quality of contaminated soil. By launching indoor pot experiment,this text studied the impacts of sole and compound pollution of petroleum and heavy metal on microbial respiration and soil enzyme activity respectively; on this basis, some microbial physiological indicators which can provide reasonable monitorings for compound pollutions of petroleum and heavy metal have been selected.It also established a kind of evaluation method of salted soil environmental quality which evaluated compound pollution of petroleum and heavy metal by use of microbiological indicators.The main findings are as follows:(1) By launching indoor pot experiment,this text studied the impacts of different concentrations of petroleum and heavy metals on microbial respiration and soil enzyme activity as petroleum and heavy metal (Nickel, Cadmium, Vanadium) for target contamination factors respectively. The main findings are as follows:When concentrations of petroleum varied from1.00%to8.00%,microbial respiration and concentrations of petroleum have a significant positive correlation.When it was at the first15days,the correlation coefficient is0.88(P<0.05).When it was at the first30days,the correlation coefficient is0.99(P<0.01).When it was at the first45days,the correlation coefficient is0.96(P<0.01).When concentrations of petroleum varied from0.00%to8.00%,catalase activity shows an increasing trend.When concentrations of petroleum is4.00%,the value of microbial biomass carbon is highest.8.00%of treatment group is lowest,which shows that high concentrations of petroleum restrain microbial growth. In all cultured time,five treatment groups showed a decreasing discipline,which indicated that heavy metal had an inhibitory effect on microbial respiration.When it was at the first45days,heavy metal and urease activity had a significant negative correlation,whose correlation coefficient is-0.94(P<0.05).When it was at the first30days,heavy metal and urease activity had a significant negative correlation,whose correlation coefficient is-0.96(P<0.05)(2) By launching indoor pot experiment,this text studied the impacts of compound pollution of different concentrations of petroleum and heavy metals on microbial respiration and soil enzyme activity as petroleum and heavy metal (Nickel,Cadmium, Vanadium) for target contamination factors respectively. The main findings are as follows:When it was at the first30,45days,with the addition of compound pollution of different concentrations of petroleum and heavy metals,catalase activity showed a decreasing discipline,which indicated that catalase activity had a strong sensitivity on compound pollution of petroleum and heavy metals. With the advance of incubation time,the impact of compound pollution of petroleum and heavy metals on microbial biomass carbon had a constant variation in salted soil,which showed a stationary decreasing trend.The urease activity of T2,T3treatment group were much lower than the other four treatment group, which demonstrated that compound pollution effects varied with pollutant concentration ratio and cultured time changing.(3) Interaction mechanism of compound pollution of petroleum and heavy metals in salted soilThe impact of T3、T4、T5、T6treatment group on microbial respiration were mainly antagonized,which showed that higher concentrations of compound pollution of petroleum and heavy metals were mainly antagonized. The impact of compound pollution of petroleum and heavy metals on microbial biomass carbon was principally synergistic.The impact of lower concentrations of compound pollution of petroleum and heavy metals on catalase activity was synergistic.However, then with combined pollution concentrations increaseing, compound effect change into antagonize.The impact of compound pollution of petroleum and heavy metals on urease activity were mainly antagonized. In addition, this trend kept unchanged,when cultured time varied.(4) One evaluation method of compound pollution of petroleum and heavy metals about salted soil environmental quality has been established by use of microbiological indicators.