no75-82

[77] Evaluation of overlooking view by solid angle and aspect ratio

- A case study of the relationship between Lake Senba borrowed scenery and tree growth

○YIHAN REN¹, Norimitsu ISHII², Yoshiaki OHSAWA¹ (1. University of Tsukuba, 2. National Institute for Land and Infrastructure Management)

Keywords:borrowed scenery, green space management, landscape, solid angle, aspect ratio, Kairakuen Park

Borrowed scenery is often used in the landscape of Japanese gardens. However, with the rapid growth of the economy and technological innovation, the original intention of the garden design may be lost. Kairakuen Park has been using Lake Senba as a focus for borrowed scenery since the Edo period. But in recent years, the overlooking view of Lake Senba is obstructed by the continuous growth of trees. Therefore, Ibaraki prefectural government has carried out active green space management such as tree cutting. In this study, we formulate a model of the overlooking view to analyze how tree growth affects borrowed scenery by calculating the solid angle and aspect ratio of the visible lake surface.