Question

Which process plays an important role in the biogeochemical cycles of carbon, nitrogen, and phosphorus?

Answer 1

The process that is significant and plays an extremely important role in all of the bio geochemical processes and cycles, including the carbon, nitrogen and phosphorus, would be to decompose and release the traces and amounts of these nutrients for the uptake of other living beings, including plants to ultimately allow for these materials to be recycled along with new nutrients to be produced again.
So,in short the answer is decomposition.

Answer 2

Fixing of components from atmosphere to earths surface and again from earth's surface to atmosphere by organisms and some natural calamities