The Soils and Their Nutrients 



241 



TABLE 7-5. Nitrogen, Phosphorus, and Water Budgets for the 

 Coastal Tundra Land Surface 



t indicates trace. 



ND indicates no data. 



♦Includes suspended particulates which are predominantly organic in origin. 



Note: Concentrations of the various forms of nitrogen and phosphorus in precipitation and runoff 



were taken from Dugdaie and Toetz (1%1), Kalff (1965), Barsdate and Alexander (1975), Prentki 



(1976) and Prentki et al. (1980). Each input or export was calculated as the product of the appropriate 



nitrogen or phosphorus concentration and the water volume indicated in the table. 



site in 1972. For the average winter precipitation of 106 mm (Chapter 2), 

 this yields 88 mm of spring runoff, which is similar to the 85-mm June 

 average discharge for Nunavak Creek for the period 1972-76 (U.S. Geo- 

 logical Survey 1971-76). During snowmelt 32.7 mg N m'' is lost, more 

 than the amount gained annually from precipitation. However, most of 

 the nitrogen in the runoff is in organic form, and only a small fraction of 

 the inorganic nitrogen present in the snowpack is lost. The retention of 

 inorganic nitrogen from the snowpack is remarkable, since meltwater 

 concentrations early in the snowmelt period range as high as 214 /.^g N 

 liter"', almost twice as high as found in the snowpack (Barsdate and 

 Alexander 1975). However, ammonium and nitrate concentrations de- 

 cline rapidly, and were below those in the snowpack by 18 June in 1973 

 (Figure 7-11). 



