In a successional community, some kinds of organisms like fungi or beetles are present in every stage of succession. however, the particular species of fungi or beetles that may be there at the earliest stages of succession are often not the same species present in the last successional stage. this is a result of:

Each species of life are able to adapt under certain conditions. When these specific conditions change, they are outcompeted by those that can survive this conditions.
The changes in the plant species, also affect the type of fungal presence available. This is because many fungi are associated with a particular plant.

Processes above and be sure to mention the movement of electrons and energy as the carbon atom moves from one reaction to another.