a compost thought..
It's worth noting that soils do not accumulate "naturally" via compost piles. Very few animals other than humans make piles of OM in such a way as to experience heating from thermophyllic microbes.
Compost is an artificial concentration of nutrients and as the concentration occurs fairly rapidly so does the effect dissipate from soil fairly rapidly, IME. I think there is an idea that compost and manure can "build up" soil to such a level that it is permanent fertility for human food production. I wish I had a dollar for every time I've heard someone say "oh that's really good soil over there because they used to keep the cows there" or some version thereof.