流域 (liú yù): Drainage area (Noun) — Meaning & Stroke Order

The river basin is very large.

We plan to go hiking in that river basin this weekend, but the weather forecast says it will rain.

Due to a lack of effective management, the water quality in this basin has not improved significantly.

The ecosystem of this river basin needs protection.

The government not only protected the basin's ecosystem but also promoted local sustainable development.