Question

How do estuaries compare in terms of production compared to other areas?

There is no productivity in an estuary.
Estuaries are the most productive of all marine ecosystems.
Estuaries are productive, but far less than other marine ecosystems.
Estuaries are the least productive of all marine ecosystems

Answer 1

Estuaries are the most productive of all marine ecosystems. They are located where the river meets the sea. The San Francisco Bay is a popular estuary.