What are dominant species?

Biomass is a measurement of dominance in an ecosystem.

A dominant species is a species that has a community impact that is proportional to its biomass. For example an elephant is a dominant species because it has a large biomass and a large impact on its community, by converting dense woodlands to grasslands that burns more readily and allows for necessary disturbance.

The higher a species are up on the food chain, the more dominant they are, as they have an impact on the species lower in the food chain.