Soils were incubated with 50 ppm 12C-pyrene and 13C-pyrene for 30 days. Soil DNA were extracted and separated by ultracentrifugation and CsCl gradient fractionation. Then, 15 DNA fractions were retrie
Soils were incubated with 50 ppm 12C-pyrene and 13C-pyrene for 30 days. Soil DNA were extracted and separated by ultracentrifugation and CsCl gradient fractionation. Then, 15 DNA fractions were retrie