Applying GIS in the evaluation of landscape aesthetics
Thesis (MA (Geography and Environmental Studies))--University of Stellenbosch, 2005.
Scenic beauty, or landscape aesthetics, should be regarded as a valuable resource, to be protected and enhanced in order to generate income. Current environmental impact assessment (EIA) studies do not include the evaluation of scenic beauty as a resource properly, due to the lack of effective evaluation methods. A general dilemma lies in objectively evaluating beauty. If scenic preferences can be associated consistently with the physical landscape features, the latter can be used as predictors of the former. Analysis of aesthetics can therefore be done with a degree of objectivity, based on these general preferences. A large number of these preferences are morphologically measurable. In other words, these preferences can be mapped in a Geographical Information System (GIS), rated, and evaluated quantitatively. The first step in objectively evaluating landscape aesthetics entailed identification and compilation from the literature of conceptual components in a landscape, i.e. the units defining a landscape. Four components were identified: landform, vegetation, water features and man-made features. Each of the four components can be subdivided into several elements. Secondly, scenic preferences that can be consistently associated with landscape features were identified. It was found that any subjective experience of landscape aesthetics would be either one of calmness or one of excitement. The presence or absence of the landscape elements, and specific combinations of elements and element variables within the context of an individual landscape, will determine the type and extent of the aesthetic experience of the viewer. Finally, this theory was put into practice. Coverages were created of a test region, with landscape elements as the features of the coverages, and element variables or characteristics as feature attributes. These landscape elements, as they enhance either calmness or excitement, were quantified by assigning value ratings to the elements according to the extent of the influence of the elements on the aesthetic value of the landscape. ArcInfo GRID functionality was used to convert the coverages to raster (or grid) overlays, using the element variables enhancing both calmness and excitement. A simple cumulative summing function was used to derive an aggregate Calm Aesthetic Experience map by adding grids enhancing calmness. An aggregate Exciting Aesthetic Experience map was constructed by adding grids enhancing excitement. Finally, these two grids were summed in order to construct a Total Aesthetic Experience map, which is an indication of the total aesthetic value of the test region. The outcome of this research was a method for analysis and objective evaluation of a landscape, using a GIS for data creation, analysis and map construction. The resultant map is an indication of aesthetic value, showing the test region graded according to intrinsic aesthetic value.