The profile distribution of iron nodules, i.e., fine brown-colored ortstein
s with strong magnetic properties uncommon for the bulk of soil, was studie
d. The results obtained and published data revealed the paramount importanc
e of microorganisms in the formation of nodules with magnetic properties. T
he capacity of soil microbial cenoses to the reduction of iron compounds is
assessed. One of the possible scenarios of the biogenic formation of low a
nd high magnetics is discussed, which agrees with the experimental data obt
ained by the Mossbauer analysis.