100 



DEPTH 



IN 



METERS 



200 



300 



350 



LEATHERY MACROPHYTES _.-"'T 



CORTICATED MACROPHYTES _ - 



PHOTIC ZONE 



TROPICS 



SUBTROPICS MEDITERRANEAN 

 LATITUDE 



BOREAL 



SUBARCTIC 



Figure 4. Biogeographical depth patterns for these algal 

 functional groups (based on literature cited in Table 1 and this 

 study) . 



18 



