Build up of organic material in soil occurs under which of the following conditions?

Raw material for decomposition represented by dead organic matter is

Which one of the following processes during decomposition is correctly described?

Identify the processes $P, Q,$ and $R$ in the following descriptions:
$I -$ The process of breaking down detritus into smaller particles $- P$
$II -$ Bacterial and fungal enzymes degrade detritus into simpler inorganic substances $- Q$
$III -$ Water-soluble inorganic nutrients go down into the soil horizon and get precipitated as unavailable salts $- R$
Select the correct option for $P, Q,$ and $R$.

In decomposition,detritivores break down detritus into smaller particles. This process is called......

The breakdown of detritus into smaller particles by earthworm is a process called