Nitrogen Biostimulation of Petroleum-Contaminated Sandy Podzolic Soil Under Boreal Conditions: Effects of Temperature, Nitrogen Form, and Contamination Level

Petroleum contamination of soils remains a significant environmental problem in boreal regions, where low temperatures constrain natural attenuation processes and complicate bioremediation. Nitrogen biostimulation is widely used to enhance petroleum hydrocarbon degradation; however, the combined effects of temperature regime, nitrogen form, contamination level, and nitrogen dosage remain insufficiently resolved for sandy podzolic soils of northern regions. This study investigated nitrogen-assist