scum barrier

例句：

1. 1. The constructionof the new highway is a significant obstacle to the development of the region.
   新高速公路的建设是该地区发展的重大障碍。
2. 2.The city's efforts to improve its environmental standards have created a sludge barrier that prevents pollution from entering the river.
   城市努力提高其环境标准，创造了一个污泥屏障，阻止了污染进入河流。
3. 3. The sludge barrier was designed to protect the fragile ecosystem from further damage.
   污泥屏障旨在保护脆弱的生态系统免受进一步损害。