Consider the following statements about an estuary : 1. An estuary is the place where the river fresh water meets with ocean water. 2. This area is highly productive. 3. This area is highly unproductive. Which of the above statements is/are true ?

Statement 1 is true: An estuary is indeed a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. It is where freshwater from rivers mixes with saltwater from the ocean. Statement 2 is true: Estuarine environments are among the most productive ecosystems on Earth. The mixing of nutrient-rich freshwater from rivers with the high productivity of marine waters, combined with shallow depths allowing light penetration, creates ideal conditions for photosynthetic organisms and supports diverse food webs. They are often important nursery grounds for fish, shellfish, and other wildlife. Statement 3 is false: Estuaries are highly productive, not unproductive.