Table 1.
Geochemical and physical characteristics of subglacial sediment pore water and subglacial bulk meltwatera
| Sample (collection date) | Physical and chemical profile |
Cation concn (μM) |
Anion concn (μM)c |
||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| T (°C) | pH | EC (μS/cm) | DO (mg/liter) | DOC (μM/ liter)b | DON (μM/liter) | DOC/DON | NH4+ | Na+ | K+ | Mg2+ | Ca2+ | Mo2+ | NO3− | NO2− | PO43− | Cl− | SO42− | HCO3− | |
| RE pore water (July 2008) | NA | NA | NA | NA | 60.0 | 0.3 | 210 | 2.5 (0.1) | 5.9 | 30.6 | 171.5 | 449.2 | 0.052 | 3.9 (0.1) | 0.3 (<0.1) | 0.04 (<0.01) | 3.4 | 270.8 | 913 |
| RE meltwater (July 2008) | 1.0 | 6.7 | 15.9 | NA | 18.3 (1.7) | 1.6 (1.4) | 12 | 0.9 (0.01) | 0.3 (0.03) | 0.2 (0.03) | 7.3 (1.5) | 91.6 (5.8) | NA | 2.4 (0.2) | BDd | NA | 0.1 (0.03) | 2.2 (0.3) | 176 |
| RW meltwater (July 2008) | 0.6 | 7.6 | 49.9 | NA | 30.8 (1.7) | 5.1 (1.4) | 6 | 0.9 (0.01) | 1.2 (0.03) | 0.9 (0.03) | 41.5 (1.5) | 247.2 (5.8) | NA | 3.2 (0.2) | BDd | NA | 0.3 (0.03) | 39.7 (0.3) | 498 |
| RE meltwater (September 2009) | 0.3 | 8.8 | 32.5 | 11.3 | 33.3 | NA | NA | BDd | NA | NA | 39.9 (0.5) | 277.0 (4.2) | BDd | 2.0 (0.3) | BDd | 0.19 (0.02) | 5.5 (0.2) | 75.1 (0.7) | 330 |
| RW meltwater (September 2009) | 0.1 | 8.7 | 32.0 | 10.9 | 24.2 | NA | NA | BDd | NA | NA | 33.4 (0.4) | 264.5 (2.9) | BDd | 3.0 (0.1) | BDd | 0.11 (0.01) | 1.5 (0.1) | 33.1 (0.1) | 413 |
a
Standard errors for replicate analyses are indicated in parentheses, where available. Abbreviations: NA, not available; BD, below detection; T, temperature; EC, electrical conductivity; DOC, dissolved organic carbon; DON, dissolved organic nitrogen; DO, dissolved oxygen.
b
Sediment pore water was assayed as nonpurgeable organic carbon. Subglacial meltwaters were assayed as DOC.
c
Sediment pore water was assayed as phosphate ions. Subglacial meltwaters were assayed as total P.
d
Detection limits were as follows: Mo2+, 1 nM; NO2−, 25 nM.