river ecosystem

例句：

1. 1. The riverecosystem plays a crucial role in maintaining thelocal biodiversity.
   河流生态系统在保持当地生物多样性方面起着至关重要的作用。
2. 2. Therestoration of the river ecosystem is essential forthe survival of many species.
   恢复河流生态系统对于许多物种的生存至关重要。
3. 3. The governmenthas launched a campaign toprotect and preserve the river ecosystem.
   政府已经发起了一场保护和保存河流生态系统的运动。