Modeling the Magnitude and Spatial Distribution of Aesthetic Impacts

Timber-harvesting operations, especially clearcutting (that is, harvesting operations where all of the trees in a given area are removed), have been criticized for many reasons, not least of which is their unsightly appearance. Forest managers have recognized this, and have attempted to place clearcuts in locations with limited viewsheds. In order to find such locations, forest managers have made extensive use of standard geographical information system (GIS) viewshed operations. The use of conventional viewshed operations ignores the possibility that the aesthetic impacts of clearcuts might be diminished by the screening effects of intervening vegetation, or the possibility that impacts simply decrease with increasing distance. In this study we found evidence that the aesthetic impacts of clearcuts do in fact diminish in these ways. Photograph transects were performed around ten clearcuts. Each transect produced a series of pictures showing the clearcut from increasing distances into the surrounding forest. The Law of Comparative Judgments (LCJ) technique was used to develop perceived-scenic-beauty rankings for each photograph. Statistical analyses showed aesthetic impacts do in fact diminish with viewing distance through screening vegetation. A modified viewshed algorithm was then developed not just to identify areas where clearcuts are visible, but also to map localized aesthetic impacts of clearcuts. The approach presented here could be used to develop similar models that map the aesthetic impacts of any proposed environmental modification.