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J. Gaspar et al. 2010. Visibility analysis and visual diversity assessment in rural landscapes
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Visibility analysis and visual diversity assessment in rural landscapes
José Gaspar 1* , Beatriz Fidalgo 1 , David Miller 2 , Luis Pinto 3 & Raúl Salas 1
1
Instituto Politécnico de Coimbra, Escola Superior Agrária, Coimbra, Portugal
2
Macaulay Land Use Research Institute, Aberdeen, Scotland, United Kingdom
3
Independent Consultant, Aveiro, Portugal
Abstract
Analysing the visibility of landscape features is usually based on methods which calculate the
number of locations from which such features are visible. However, visibility analysis using
Geographic Information Systems (GIS) suffers from several limitations which can significantly
influence the results. In this study the authors have tested the differences in visibility through
time, and used a Digital Elevation Model which includes the heights of land cover features.
The results provided information about the visibility of each land cover type, at each of three
dates: 1954, 1974 and 1995. The derived maps of visibility were used as inputs to analysis of
the visual content of the landscape, which were then used to evaluate the visual diversity at each
date, and to provide an input to the derivation of information on landscape visual quality. The
results show significant differences in both visual content and diversity through time, and
illustrate a difference between the potential perceptions of change, and the real extent of change
in an area.
Keywords: visibility analysis, landscape visual diversity, landscape content
1. Introduction
The planning and management of land use requires an understanding of the benefits and impacts
of change with respect to environmental, economic and social objectives. One aspect of
management which links across these three broad headings is in relation to the visual landscape,
and the contributions made by the extent and distribution of different types of land cover, and
associated uses. An analysis of diversity in the visual landscape, and how it changes through
time (Antrop, 2005), is an aid to understanding the wider significance of the impacts of drivers
of ch’ange (Bell, 2001) (e.g. climate change; demographic change) and the consequent changes
in land cover (e.g. forest fire; urbanisation) than only the areas they occupy.
An analysis of the visibility of land cover types, and associated uses was undertaken, based on
the methodology applied by Miller (2001), Gaspar et al. (2002) and Ode (2003). The outputs
provided a basis for deriving indicators of visual diversity in the landscape, and the visual
complexity and content in the view.
* Corresponding author. Tel.:+351 239802940 - Fax:+351 239802979
Email address: jgaspar@esac.pt
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.