The term 'Tianmian Layer Landscape Effect Diagram' refers to an illustration or visual representation of the landscape at the Tianmian layer, which is a specific altitude level or stratum in a mountainous or elevated area. Such diagrams are often used in architectural and environmental design to depict the visual appearance of a landscape from a certain vantage point. They can include details such as vegetation, terrain features, and human-made structures, and are crucial for planning and visualizing future developments or natural landscapes.