210Urbanization models and the regions
Forthe transportation-corridors model, the distance from metro-area border
to the satellite city is divided into three equal segments. In the first time stage
(reaching 1.5 times metro area), the road segment nearest the metro area receives
twice as much development as the middle segment, which in turn receives twice
as much as does the farthest road segment near the satellite. In the final third
stage (3 times metro area) all three road segments receive the same amount
of development. The second intermediate stage (reaching 2 times) is half way
between the first and third stages in distributing development along the trans-
portation corridor.
Thus in the model, 41 % of the urbanization occurs along the road segment
nearest the metro area, 32 % along the middle segment, and 27 % along the dis-
tant segment. This mosaic sequence of progressively extending outward, both
radially from the metro area and in parallel bands from the highway, reflects the
initial prominence (or source effect) of the metro area followed by the growing
prominence of strip development along the road and influence of the satel-
lite city.Dispersed-sites model mosaic sequence
All urbanization occurs in equal-sized small patches dispersed outside
themetropolitan area, and number of development patches per time period
decreases with distance from the metro-area border. This dispersed-patch, low-
density development model mimics sprawl.
Forthe model, five ‘‘concentric” bands around the metropolitan area are out-
lined, somewhat analogous to zones in the concentric-zones model. Band sizes
are scaled to the initial metro-area size, so the area of the first band equals half
themetro area, and area of each of the four outer bands equals the metro area.
The size of development patches is also scaled to the metro-area size, reflect-
ing an assumed rough correlation between city size and average development
size. In the model, each patch of development equals 2.5 % of the initial metro
area. Doubtless this is much larger than reality, but it significantly facilitates
calculation and mapping, and effectively illustrates the dispersed-sites model in
contrast with the other urbanization models.
The first time stage (which reaches 1.5 times the metro area) distributes the
small dispersed patches as follows: 50 % in band one, 25 % in band two, and
25 % in band three. The second stage (2 times the initial metro area) distributes
25 % of the development patches in each of the bands one, two, three, and four.
The final third stage (reaching 3 times) distributes 25 % of the patches in each
of bands one, three, four, and five. Development patches are dispersed within a
band and between bands so that they are relatively similar distances apart.