Urbanization options evaluated 219worldwide pattern by having about the same number of 1 sand 4 sinboththe
concentric and satellite category and the transportation and dispersed category.
Overall these divergences seem minor. The worldwide pattern for urbanization
summarized in the guiding principles seems to apply well in virtually all the
urban regions.
Table 8.2 also shows no correlation between urbanization-model response
pattern (distribution of best and worst models) and either broad geographic area
(Europe, Africa, Latin America, etc.) or city population size (see Table5.1). These
results parallel those found for numerous attributes associated with nature,
food, water, built systems, and built areas in the urban regions (Chapters 6
and7).
Acloserlook at thespecific attributes,alongwiththeir response patterns,
in this overall evaluation of urbanization options is useful (Table 8.2). The first
two attributes, biodiversity and recreation/tourism sites, in general are widely
distributed small areas of nature-and-people importance. Forest, grassland, and
desert attributes primarily measure the broad urbanization effect on natural
land in urban regions. Nearby slopes facing a city have diverse implications from
aesthetics to landslides, erosion, sedimentation, city air ventilation, and proxim-
ity of species-source habitats. Six water-related attributes (rivers/major streams,
major wetlands, flood hazard, marine coast, reservoirs/lakes, and drainage area
forwater supply) cover an extensive set of natural-systems-and-people issues cen-
tral to the present and future of urban regions. Market-gardening areas in prox-
imity to a city also reflect a range of benefits from food to economics and clean
air. Distance from major highway reflects overall transportation costs and infras-
tructure effects on the land. Three attributes measuring diverse implications of
urbanization (subdividing a region, edge density, and average distance from city
center to metro-area border) produce identical patterns for all regions, which
basically result from geometry (algorithms) in the four urbanization models.
Subdividing a region with strip development disrupts regional connectivity for
species movement. Edge density is an index of numerous effects of built areas
on natural systems (Chapter7). Average distance from city center to metro-area
border measures how isolated city residents and city parks are from the sur-
rounding countryside. Finally, ‘‘other attributes considered” is simply a mix of
dissimilar characteristics measured -- greenbelt, urban growth boundary, Native
Peoples’ land, aquaculture, and fire hazard -- each with a fairly limited sample
size. In short, this array of attributes evaluated (Table 8.2), like those highlighted
in Chapters6 and7,nicely illustrates the regional focus on natural systems and
their uses for society.
Especially high average rankings (1.0 to 1.9) or low rankings (3.0 to 4.0) for
an attribute (Table 8.2) indicate considerable consistency, or low variability, in