海洋国土territorial waters(plural); blue territory

• 随着“蓝色国土”的观念越来越深入人心，人们向海洋索取的脚步在明显加快。

  As the concept of "blue territory" penetrates deeper and deeper into people's hearts, the steps that people take towards the ocean are becoming markedly faster.

• 王登平代表谈及守好蓝色国土、维护海洋权益等话题。

  Delegate Wang Dengping talked on topics such as defending territorial waters and maintaining maritime rights.