Diesel fuel contamination in soils may be
toxic to soil
microorganisms and plants and acts as a source of groundwater contamination. The objective of this study was to evaluate the soil
biological activity and
phytotoxicity to garden cress (Lepidium sativum L.) in a soil polluted with
diesel fuel. For this, a
diesel fuel spill was simulated on agricultural soil at dose 1 l m(-2). During the experiment (400 days) the soil was not covered in vegetation and no agricultural tasks were carried out. A stress period of 18 days following the spill
led to a decrease in soil
biological activity, reflected by the soil
microbial biomass and soil
enzymatic activities, after which it increased again. The n-C(17)/Pristine and n-C(18)/
Phytane ratios were
correlated negatively and significantly with the
dehydrogenase, arylsulphatase,
protease,
phosphatase and
urease activities and with the soil
microbial biomass during the course of the experiment. The
beta-glucosidase activity indicated no significant connection with the parameters related with the evolution of
hydrocarbons in the soil. Finally, the germination activity of the soil was seen to recover 200 days after the spill.
