Exploring GIS presents a nested set of concerns, each influencing the others; outwards, the rings consider measurement, representation, operations, transformations, and context.

Dane County Land Records Project

(presented in REVERSE order)

Social Context:

Society (politics, media, etc.) has become aware of soil erosion produced by farming practices.

Institutional:

Legislature created a mandate requiring counties to produce a plan to meet certain soil erosion goals by a given date.

Information component

1982: Most counties proceed using manual methods, in Dane County, University of Wisconsin attempts to demonstrate GIS (still experimental at that time)

Transformations:

Existing records must be made compatible. Soil erosion require six distinct 'layers' of information, measured differently. Physical model must be linked to parcel units on which decisions are made and programs operated.

Operations:

Overlay, primarily. (prediction of soil loss and possible changes in farming practices)

Representation:

Structure information resources to meet the objectives of the mandate. Unified spatial reference system had to be assembled, each source registered to a set of known points.

Measurement:

choices to obtain raw facts about environment to serve the purpose. Project relied on existing records: soils maps (many attributes attached to a set of zones), parcels, wetlands, etc.

Bottom Line:

Order of Magnitude improvements in geopositioning, automation, interpretation and processing

PLUS unexpected benefits in handling issues not yet known.

Niemann, B. J.; Sullivan, J. G.; Ventura, S. J.; Chrisman, N. R., 1987: Results of the Dane County Land Records Project, Photogrammetric Engineering and Remote Sensing 53, October, 1371-1378.