Carbon and Nutrient Budgets 463 



TABLK 12-2 Standing Crops of Carbon in the 

 Coastal Tundra at Barrow 



Note: The moist meadow is a mosaic of vegetation types. Standing 

 crops of each vegetation type are weighted by relative area (Chapter 

 3). Localized variations in these values are discussed in the text. 



intensive study site (Figure 12-1). The greater vascular aboveground 

 standing crop in the intensive site in 1971 (Figure 12-1) than in a variety 

 of other Carex-Oncophorus meadows in 1972 (Table 3-2) suggests sub- 

 stantial yearly and/or microtopographic differences in production. Esti- 

 mates of belowground standing crop range from 207 to 574 g C m'\ de- 

 pending upon the microtopographic unit (Chapters 3 and 6). The above- 

 to belowground ratio of live vascular plants is about 1:10 (Dennis and 

 Johnson 1970, Dennis 1977), similar to that found in a shortgrass prairie 

 (Clark 1977). The carbon in moss at Barrow (51 g C m'^) is twice that in 

 vascular aboveground parts. Algae and lichens are less important com- 

 ponents of biomass (Table 12-2). Standing dead and litter constitute a 

 larger standing crop (56 g C m'^ than the live vascular material above 

 ground and retard nutrient cycling by altering the radiation regime with- 

 in the canopy (Chapter 3) and by directly immobilizing nutrients (Chap- 

 ters 8 and 9). 



Bacteria constitute the largest standing crop of decomposer organ- 

 isms (6.0 g C m"^), three times that of fungi, although the balance be- 

 tween fungal and bacterial biomass varies strikingly with habitat and soil 

 depth (Chapter 8). Soil invertebrates account for 1.8 g C m"^ (Chapter 



