Table XXXII. Comparative leaf area indices at Barrow and Prudhoe Bay. 



Live Leaves 



SUM 



0.762 



0.733 



0.818 



0.903 



0.8d4 



1.201 



Standing Dead 



HEIGHT IN 

 CANOPY, CM 



-X TO -O.l* 



4.9 

 9.9 



TO 



5 TO 



10 TO 14.9 



15 TO 19.9 



20 TO 24.9 



SUM 



1.354 



0.762 



0.564 



1.213 



0.973 



1 .2^0 



* MICROTOPOGRAPHIC CHANGES BENEATH THE FRAME Re*t)LTE» IN SOME CONTACTS BELOW 

 MEAN GROUND LEVEL. THESE VALUES ARE UNCORRECTED FOR THIS ERROR. 



Despite the differences in structure of the vegetation at Prudhoe Bay and Barrow, the seasonal 

 primary production is quite similar (Table XXXIV). In Prudhoe Bay, the wettest site (site 3) was the 

 most productive and the driest site (site 1) was the least productive. Associated with the increasing 

 moisture gradient, however, was a consistent decrease in standing dead material. This agrees with 

 results obtained near Barrow and suggests a more rapid turnover of vegetation and nutrients with an 

 increase in moisture. The Barrow communities possess considerably more chlorophyll than those at 

 Prudhoe, especially wlien calculated on a dry weight basis, suggesting a greater proportion of 

 photosynthetic tissue in the Barrow plants. This was associated with a higher chlorophyll a:b ratio 

 in the plants from Prudhoe Bay (3.47) than in those from Barrow (2.96). 



In summary, the vegetation at Prudhoe and Barrow is similar in production and in dominant 

 species. The two areas differ, however, in that there is greater habitat diversity, a taller nwre open 

 canopy, and, apparently, a lower amount of chlorophyll in the plants at Prudhoe. These tentative 

 conclusions need to be verified by additional observations in the Prudhoe Bay area before the signi- 

 ficance and interpretations can be stated. 



91 



