Prediction and Evaluation of Landscape Change Caused by Open-cut Mining

Landscape destruction after open-cut mining gives to the social impression. This paper presents the method to predict and evaluate landscape changes caused by open-cut mining. Landscape changes with the progression of mining are simulated by the use of digital terrain models, and that are shown on the computer graphic screen. Evaluation tests are conducted by using of photomontages composed of computer graphics and present appearance photographs. Two psychometrical evaluation methods, rating-scale method and selection method, are adopted to estimate the allowable scale of mined-out quarry from the viewpoint of landscape engineering. In this study, two quarries are chosen as the examples of case study. From the results of evaluation tests, it is shown that the landscape impact of mined-out quarry is subjected to the height ratio against the background mountains and the apprarent height of mining slope. Especially, the apparent height of mining slope is a important factor for landscape evaluation. It becomes clear that the allowable limit of the apparent height of mining slop is about 0.037. This value is equal to the visual angle of 1°, at which an ordinary person can distinguish the object observed. The apparent height 0.037 is therefore the quantitative criterion for the allowable scale of mined-out quarry from the viewpoint of landscape conservation.