LA/UP 341 Fall 1999

Expert-based Evaluations of Visual Quality

Readings:

Gobster, Paul H. and Richard E. Chenoweth, 1989. The Dimensions of Aesthetic Preference: a Quantitative Analysis. Journal of Environmental Management 17, 47-71.

Compositional -- Formal Aesthetic

Faced with an urgent need for a system by which to assess the landscape, the agencies turned to the existing literature of visual assessment and, notably, the work of R. Burton Litton (Litton, 1968) with the US Forest Service Pacific Northwest Forest and Range Experiment Station. Litton's work, and the resulting assessment systems, attempted to generate objective measures of aesthetic qualities by looking at what the professions already knew about landscape aesthetics.

The traditional aesthetic judgement approach of landscape designers was analyzed in the search for identifiable consistent qualities that could be described and measured.

Concepts:

Landscape character is primarily determined by the four basic visual elements of form, line, color and texture. Although all are present in every landscape, they exert varying degrees of influence.
The stronger the influence exerted by these elements, the more evidence there will be of the aesthetic principles harmony and contrast, and hence the more interesting the landscape.

Closely allied to this "formal aesthetic" model is a "biological-ecological" model in which assessments are made of the varieties of species available and of the interrelationships of these with their environment and each other. Both models are implicitly based on the following ideas:

Increasing variety or diversity of composition, either aesthetic or biological, will lead to increased beauty.
Beauty (or ecological quality) is an inherent quality of the landscape and will be apparent to most observers regardless of their background, mood, or professional orientation.
Man-made alterations to natural systems are intrinsically non-beautiful (or ecologically unsound) and are destructive of harmony.

Examples:

The US Forest Service developed and uses a system called VMS (Visual Management System), the Bureau of Land Management has VRM (Visual Resource Management) and the Soil Conservation Service has a similar procedure. In Australia, the Victorian Department of Conservation, Forests and Lands uses VMS (Visual Management System).

Operation:

For all the agencies mentioned the systems are conceptually and operationally similar -- each has two parts:

Inventory/Evaluation

In the US the Forest Service and the BLM, shortly after adopting their two systems in the mid-1970s, started to compile inventories of visual resources under their jurisdictions. The process was substantially complete by 1981 although some pockets of land are still outstanding and work on these is hampered by budgetary considerations. Most Forests now have a map of Management Classes which places restrictions or guidelines on proposed activities on their land.

Contrast Rating/Visual Absorption Capability

When development is proposed, the contrast between that development and its surroundings, or the ability of the landscape to absorb the impact, is assessed. The rating guides the Land Use Planner in making judgments about project suitability or possible modifications.

Ultimately the visual assessments are the tools used by Forest Management to represent aesthetic goals in the trade-off between economic (crop value), environmental (biological), and aesthetic considerations.

Vegetation	Landform/ Built Form	Amenities	Imageability	Influence of Adjoining Land Use
Variety of vegetation, well maintained, designed, orderly or "natural", interesting forms, etc.: 5	A variety of shapes and forms of urban spaces. Spaces may be delineated by buildings, plantings, or topography: 5	Pedestrian- friendly amenities, e.g., Sidewalks, parks, benches, boulevards, banners, etc.: 5	Numerous places of Historical, Cultural, or Architectural significance. Distinctive, rare. Landmarks: 5	Adjoining land uses are compatible, but not homogenous and monotonous. Incompatible uses are well buffered: 5
using the end-points defined in these narratives, pick intermediate values	<-- same as Veg.	<-- same as Veg.	<-- same as Veg.	<-- same as Veg.
Not maintained, overgrown and unkempt, or non-existent: 0	Little spatial definition. Built forms are un- differentiated. Vegetation does not define spaces. Topography flat: 0	Few or no sidewalks, automobile dominated. No parks, street plantings etc.: 0	No significant places or structures -- common: 0	Incompatible uses, poor zoning. Uses are monotonous, boring: 0
Vegetation quality: Native or appropriate species: 0 Noxious weeds, hazardous (e.g. falling limbs), dead: -5	Visual order: Environment is well-organized and harmonious:0 Places are cluttered, dis-organized. Discordant: -5	Amenity Quality: High quality fittings, clean, maintained: 0 Vandalized amenities, garbage, litter, graffiti: -5	Landmark quality: Cared-for, well-maintained: 0 Un-maintained, littered, obstructed: -5	Neighborhood Quality: Quality architecture, non-polluting: 0 Hazardous, polluting, otherwise unacceptable neighbors: -5

Readings for next Monday:

Steinitz, Carl, Paul Parker, and Laurie Jordan, 1986. Hand-drawn overlays: their history and prospective uses. Landscape Architecture 66(5) 444-455.

Hopkins, Lewis D., 1987. Methods for Generating Land Suitability Maps: A Comparative Evaluation. AIP Journal, October 1987. 386-400.