Russian to English Science Environment & Ecology soil ecology

Hello, I have a scientific report about the effects of oil pollution on soil ecology, and the sentence I have a problem with is:

По экспериментальным данным показаны особенности изменения ОВ почвы под действием углеводородного загрязнения в зависимости от минералогического состава.

I think there are two options for ОВ: Окисительно-восстановительный or Органическое вещество - or perhaps neither is correct. If anyone has an idea, could you let me know please?

Thank you.