124 



L. L. Tieszen et al. 



2 4 6 e 10 12 

 Mean Daily Air Temperature, "C 



FIGURE 4-11. The simulated effect of various 

 temperature optima for photosynthesis on daily 

 net photosynthesis of Dupontia fisheri and Di- 

 cranum elongatum at varying mean daily air 

 temperatures. Also presented is the frequency 

 of days with the indicated mean temperatures 

 during 15-30 June, July and August, 1970-73. 

 (After Oechel et al. 1975 and Miller et al. 1976.) 



