c . An estuary is not a freshwater ecosystem.
- Fresh water ecosystems are the water based ecosystems they include minimum to no salt content.
- In fresh water ecosystems the water content replenishes with the supply of fresh water from river, rain, or any other water source.
- The fresh water ecosystems support large population of aquatic animals and plants.
- Lakes, ponds, streams, and rivers are the examples of water ecosystems but is not a water ecosystem.
- Estuary is a saline water ecosystem.
- Estuary is a water body which also receives freshwater from rivers and salt water from the oceans.
- The organisms living in are tolerant to both supplies of water and saline water.
Hence, among the options given river, lake, and stream all are the examples of fresh water ecosystem but estuary is not an example of fresh water ecosystem.
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