chernozem

As nouns the difference between soil and chernozem

is that soil is (uncountable) a mixture of sand and organic material, used to support plant growth or soil can be (uncountable|euphemistic) faeces or urine etc when found on clothes or soil can be a wet or marshy place in which a boar or other such game seeks refuge when hunted while chernozem is a fertile black soil containing a very high percentage of humus (3% to 15%) and high percentages of phosphoric acids, phosphorus and ammonia.

As a verb soil

is to make dirty or soil can be to feed, as cattle or horses, in the barn or an enclosure, with fresh grass or green food cut for them, instead of sending them out to pasture; hence (such food having the effect of purging them), to purge by feeding on green food.

As an adjective fertile

is (of land etc) capable of growing abundant crops; productive.

As a noun chernozem is

a fertile black soil containing a very high percentage of humus (3% to 15%) and high percentages of phosphoric acids, phosphorus and ammonia.