The total petroleum hydrocarbon (TPH) degradation and the related soil biological activities in a diesel-contaminated soil were monitored during a 60-d incubation period in a laboratory study. Three treatments were carried out: uncontaminated soil (S) (control), soil contaminated with 10,000mg of diesel oil kg-1 of soil (CS), and contaminated soil plus surfactant Tween 80 at 3% w/w (CSS). Microbial respiration, seed germination index, and dehydrogenase, ß-glucosidase, and lipase enzyme activities were monitored during incubation. The relationships between soil biological parameters and the TPH levels of the total were investigated. Results indicate that the extent of TPH degradation, of about 50% either in CS and CSS, resulted positively related with microbial respiration and negatively with soil lipase activity. The hydrocarbons depressed seed germination index, while the addition of the surfactant showed a positive effect, counter-balancing the negative influence of TPH. The addition of the surfactant increased the degradation rate of hydrocarbons, microbial respiration and dehydrogenase and lipase activities, as well as germination index, while it had no effect on ß-glucosidase activity. The best biochemical parameters for testing hydrocarbon degradation and for monitoring the contamination of diesel oil polluted soil were lipase activity and soil respiration.
Soil biological activities during hydrocarbon degradation of a diesel-contaminated soil in the presence of surfactant
CARDELLI, ROBERTO;SAVIOZZI, ALESSANDRO
2006-01-01
Abstract
The total petroleum hydrocarbon (TPH) degradation and the related soil biological activities in a diesel-contaminated soil were monitored during a 60-d incubation period in a laboratory study. Three treatments were carried out: uncontaminated soil (S) (control), soil contaminated with 10,000mg of diesel oil kg-1 of soil (CS), and contaminated soil plus surfactant Tween 80 at 3% w/w (CSS). Microbial respiration, seed germination index, and dehydrogenase, ß-glucosidase, and lipase enzyme activities were monitored during incubation. The relationships between soil biological parameters and the TPH levels of the total were investigated. Results indicate that the extent of TPH degradation, of about 50% either in CS and CSS, resulted positively related with microbial respiration and negatively with soil lipase activity. The hydrocarbons depressed seed germination index, while the addition of the surfactant showed a positive effect, counter-balancing the negative influence of TPH. The addition of the surfactant increased the degradation rate of hydrocarbons, microbial respiration and dehydrogenase and lipase activities, as well as germination index, while it had no effect on ß-glucosidase activity. The best biochemical parameters for testing hydrocarbon degradation and for monitoring the contamination of diesel oil polluted soil were lipase activity and soil respiration.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
