英语翻译不拆大坝比拆了大坝更威胁野生动物,因为每年游客在湖中游玩时所造成的垃圾对环境的污染很严重,对下游的鱼的威胁比外来

The environment pollution is very serious,that,every year ,the tourists throw the rubbishes into the lake when they enjoy their trip,so that the pollution menaces the downstream fishes is more than the alien species.So,before the dam is not removed,the wild animals are more dangerous than removed it .