The Vegetation: Pattern and Succession 209 



Totol Number Speci 



Vegetation Types Totol Number Species 



I A 111— IV T- — VII 29 A 67—62 T- 14 



. 11-- ^Vl-^ ^70-^ ^32- 



Number of Forbs Number of Woody Dicotyledons 



I6-. ^12. 

 7 A 11—14 T-i 5 I A 2^2^ T- 



f^ r/\-\ tA 0\^ 



•22-^ ^6-^ ^~-4-^ ^^0- 



Number of Grominoids Forbs: Grominoids 



5 A 10 — 12 T- — 5 1,4 A I.I — 1.2' T- — 1.0 



■II ^10 2.0 0.6" 



Number of Bryophytes Number of Lichens 



'0-\ /-'O^ 19-^ ^I0,» 



5 A 19 — 19 T- 4 II A 25 — 15 T— 



•17-^ ^10 ^16-^ ^6- 



Foliage Area Index Net Aboveground Productivity 



0.3 A 0.4-0.4 T— 0.6 18 A 39—45 T- — 115 



FIGURE 6-10. The distribution of the species di- 

 versity (number of species per 10 m^) of the major 

 growth forms, foliage area index, and annual net 

 aboveground vascular productivity within the suc- 

 cessional sequence diagram. The Roman numerals 

 represent the positions of the vegetation types and 

 the letters A and T represent the starting points of 

 alluvium (A) and thaw lake (T) successions. Foli- 

 age Area Index refers only to vascular plants. See 

 Figure 6-9 for vegetation types. (After Webber 

 1978.) 



Foliage area index is low in the Cochlearia meadow, increases in the 

 alluvial sequence to the Salix heath and then decreases slightly in the 

 Luzula heath. It is highest in the Arctophila pond margin and decreases 

 in the thaw lake cycle to the Carex-Oncophorus meadow. Annual above- 

 ground vascular productivity decreases steadily with succession. From 

 the Cochlearia meadow through the Carex-Poa meadow and Salix heath 

 to the Luzula heath, productivity decreases from 47 g m'^ yr"' to 18 g m"^ 

 yr"'. From the pond margin through the Dupontia meadow to the 

 Carex-Oncophorus meadow productivity decreases from 115 g m"^ yr"' 

 to 45 g m"^ yr"'. 



