Question

how are ecosystems named?

Answer 1

they are named Either Based on the abiotic environment (Eg. Freshwater Marine)
or Based on the primary/dominant biotic organisms/species in the community...

Answer 2

ecosystems are named
abiotic
physical rather than biological; not derived from living organisms.
biotic
resulting from living things, especially in their ecological relations.
these are two meanings of the words, hope that helps

seerena, you are correct