The Vegetation: Pattern and Succession 187 



Environmental Factors 



Crazing 



Growth Form Characteristics 



FIGURE 6-1. The principal environmental factors, plant growth form 

 characteristics, and plant growth forms in the coastal tundra at Barrow. 



TOPOGRAPHIC VARIATION AND VEGETATION 

 PATTERNS IN THE COASTAL TUNDRA 



Topographic and Environmental Variations 



Topographic variation in the coastal tundra at Barrow causes var- 

 iation in the environmental factors which control the growth and dis- 

 tribution of different plant species and growth forms (Table 6-1). The 

 controlling factors can be indicated by the techniques of factor analysis 

 or ordination (Whittaker 1967), The phytosociological gradients formed 

 by indirect ordinations are interpreted as complex environmental gradi- 

 ents which represent the probable major controlling factors. Using these 

 techniques, 9 of a total of 17 measured environmental factors were sig- 



