This type of organism breaks down dead material in an ecosystem. herbivore producer omnivore decomposer

Decomposers are organisms that break down dead material in an ecosystem. 

This is what i found on google “phytoplankton, tiny organisms that live in the ocean, are autotrophs. some types of bacteria are autotrophs. most autotrophs use a process called photosynthesis to make their food.” i hope this you for what your looking for