Some Concepts That Underpin GIS - Introducing Geographic Information Systems with ArcGIS - page 6

Keys to Maps

Soil Suitability Land Use

Poor suitability Urban

Suitable Agriculture

Brushland

Forest

Wetlands

Barren

Streams and Sewers

Light solid lines: Stream
Heavy solid lines: Sewers
Light dashed lines: Coastline (and border)

FIGURE 1-1 Key to maps of the Wildcat Boat Facility area

Figure 1-3 is a soil suitability map. Lines separate soils of different types. The different soils are
categorized as suitable or unsuitable for building. Therefore, you will see the same symbol on both sides
of a dividing line, indicating that, while such soil types may be different, their suitability is the same.

Figure 1-4 is a map that shows the streams (narrow lines) and sewers (broader lines).