Fig. 2From: Diagnosing bioremediation of crude oil-contaminated soil and related geochemical processes at the field scale through microbial community and functional genesVariations in a oil content, b–d nitrogen concentration, and e–h other physical and chemical parameters. A five-point sampling, coning, and quartering method was used to collect samples, thus a mixed sample was collected in each block at each time. Error bars present the standard deviation (SD) of test results (n = 2)Back to article page