ChileanJAR

The activity of some metabolical groups of microbes has been studied in three depths of a ñadi soil.
Under natural conditions, the organic carbon and nitrogen mineralize at a reduced rate which allows for accumulation of organic matter.
In the laboratory, these processes are accelerated by an increase in temperature and by furnishing energetical substrates; high figures of CO₂ evolution and a marked accumulation of mineral nitrogen are obtained, which implies the presence of a potentially very active population.
A similar effect is obtained, from a given level on, with phosphorous, which liberates a great amount of easily assimilable carbon and ammonia.
Nitrogen by itself would not be a limitant factor in the formation of nitrates, but as the ammonia-producing microorganisms are heterotrophs, they need energetical substrates; in the last end, it is the carbon cycle which holds backs the nitrogen cycle.
The lacking of a source of available energy is postulated to be a limitant factor of the process of mineralization, as the carbon would be partially immobilized, be it biologically or held by the mineral colloid.