122 R. T. Prentki et al. 



TABLE 4-17 The Dissolved Reactive (DRP) and Dissolved Total Phosphorus 

 (DTP) in the Interstitial Water of Several Ponds 



Values are the mean, the standard deviation and the number of samples. 

 From Barel and Barsdate (personal communication). 

 ^Samples collected from bore holes open at 7 cm and 22 cm below tundra surface. 



identical; this indicates that there is but a single binding complex rather 

 than two chemically distinct pools. The phosphorus in the combined 

 NH4F and first-NaOH pools appears to be identical to the resin- 

 exchangeable inorganic phosphorus. The only sorbent for the phosphorus 

 in the intensively studied ponds is extractable iron (as Fe^Oa) which 

 accounts for 18 to 61% of the ash weight in surficial sediments. Clay 

 concentrations in the sediments are almost unmeasureable and calcium 

 concentrations (as CaO) account for only about 1% of ash weight. The iron- 

 sorbed phosphorus is in dynamic equilibrium with phosphorus in solution 

 and is potentially mobile and responsive to various limnological 

 conditions. 



These results are similar to the expected values for an unpolluted 

 temperate latitude lake which receives little detrital input (Williams et al. 

 1971a, Frink 1969, Harter 1968), although the reductant soluble 

 phosphorus and organic P are high in respect to NH4-P and NaOH-P, and 

 the Barrow phosphorus levels are in the lower portion of the range of 

 reported values. Interstitial DRP concentrations, however, are 

 exceptionally low compared to sediment values of temperate lakes 

 (Holdren et al. 1977, Glass and Poldoski 1975, Barko and Smart 1980, in 

 press). Barrow terrestrial soil samples are quite similar to the pond 

 sediments, perhaps reflecting both a common origin as ancient lake 

 sediments and the present-day similarity of environments. Distinct 



