Raw material for decomposition represented by dead organic matter is

In which layer of soil does decomposition occur at the maximum rate?

Which of the following cycles would be affected if the decomposers of an ecosystem were to vanish?

Which of the following maintains the balance of the material cycle?

$A$: Warm and moist environment can enhance the rate of decomposition.
$R$: Warm and moist climate leads to create anaerobic conditions which promote decomposition.

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 $R$.