Microbiology of Soils
Nitrogen oxidation (nitrification)refers to the

None of these
changing of atmospheric nitrogen (N2) to nitrogen compounds
conversion of ammonium ions into nitrates through the activities of certain bacteria.
sulfur is oxidized to the sulfate form through Thiobacillus bacteria

ANSWER DOWNLOAD EXAMIANS APP

Microbiology of Soils
Nitrogen fixation

both (a) and (b)
fix the free nitrogen (N2) by which it should not be usable by plants
changes the free nitrogen (N2) to a form usable by plants
especially changes nitrogen compounds, mostly amines such as NH2

ANSWER DOWNLOAD EXAMIANS APP