The regional ecological system is fragile. 區域生態系統脆弱。
The ecology system will be broken if too many trees were felled. 過度砍伐樹木會破壞生態系統。
Cephalopod belongs to an important economic mollusk and also plays an important role in the marine ecological system. 摘要頭足類不僅是重要的經濟軟體動物，同時在海洋生態系中扮演著重要的角色。
If the species of the original system have been lost or invaders have appeared, the former pristine conditions may never be regained. 如果原本生態系中的物種消失了，或有外來物種入侵，這個生態系可能永遠無法回復原貌。
