Table 1. Standardized terms that describe major points along a gradient or urbanization. These terms are most meaningful at relatively large ( > 1 km2) scales (Marzluff et al 2001).

Term  
Percent built
  
Building density
  
Residential human density
Wildland  
0–2
  
0
  
< 1/ha
Rural/exurban  
5–20
  
< 2.5/ha
  
1–10/ha
Suburban  
30–50
  
2.5–10/ha
  
> 10/ha
Urban  
> 50
  
> 10/ha
  
> 10/ha