286
G.A . Bradshaw et al.
Natural Sources of Landscape Heterogeneity
Spatial Heterogeneity
The most prominent pattern observed at the regional scale within the
Pacific Northwest is the distinct longitudinal anisotropy manifested as
broad north- to south-running vegetation (Figure 14.2). These vegetation
patterns reflect interactions between strong west to east temperature and
precipitation gradients modulat ed by long-term climatic variation (Franklin
& Dyrness, 1973; Franklin , Swanson , Harman et al., 1991; Swanson,
Franklin , & Sedell, 1990). Although precipitation gener ally increases as
one moves northward, local variability in moisture patterns occurs as a
Figure 14.2. AVHRR image (resolution 1 km X 1 km) of the Pacific North west
region covering Oregon and Washington states.
G.A . Bradshaw et al.
Natural Sources of Landscape Heterogeneity
Spatial Heterogeneity
The most prominent pattern observed at the regional scale within the
Pacific Northwest is the distinct longitudinal anisotropy manifested as
broad north- to south-running vegetation (Figure 14.2). These vegetation
patterns reflect interactions between strong west to east temperature and
precipitation gradients modulat ed by long-term climatic variation (Franklin
& Dyrness, 1973; Franklin , Swanson , Harman et al., 1991; Swanson,
Franklin , & Sedell, 1990). Although precipitation gener ally increases as
one moves northward, local variability in moisture patterns occurs as a
Figure 14.2. AVHRR image (resolution 1 km X 1 km) of the Pacific North west
region covering Oregon and Washington states.