The Coastal Tundra at Barrow 



TABLE 1-1 Average Air Temperature, Precipitation, 

 Windspeed, Solar Radiation and Day 

 Length at the Village of Barrow 



Note: Radiation based on 14-year record; air temperature, precipitation 

 and windspeed 1941-70 normal (U.S. Department of Commerce). 

 Source: After Bunnell et al. (1975). 



the onset of positive degree-day accumulation. A portion of the micro- 

 flora is active below -6°C (Chapter 9). Thus, the period of microbial ac- 

 tivity exceeds that of primary producers by 10 to 30 days, but rates of ac- 

 tivity are low at such low temperatures. 



The total known vascular plant flora of the Arctic Slope comprises 

 574 taxa. The largest number of species, 516 or 90% of the total, are 

 found in the Foothills province (Table 1-2). Species richness is greatest in 

 the Foothills, intermediate in the Brooks Range, and least on the Coastal 

 Plain for each of the three major plant groups analyzed: vascular plants, 

 mosses and hepatics. Arctic endemics, species found only north of the 

 treeline, make up 8% of the vascular plant flora, 9% of the hepatics, and 

 only 2% of the mosses. Data for lichens are insufficient for detailed anal- 

 ysis, although some recent publications are now available (Moser et al. 

 1979, Thomson 1979). All three plant groups show considerable floristic 

 overlap among the provinces of the Arctic Slope and between the Arctic 

 Slope and the region south of the latitudinal treeline. This overlap is a 

 result of the occurrence of tundra at higher elevations south of the crest 

 of the Brooks Range, and of some tundra species which also grow in for- 

 est habitats (Murray 1978). 



The two Biome research areas on the Coastal Plain — Barrow and 



