| Report Year: 2009 |
| Arrowhead Pond (Pottawattamie), Pottawattamie County |
| Carbon Balance Table |
| Parameter | 7/14/2009 | 6/10/2009 | 2009 | 2008 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 |
| Alkalinity as CaCO3 (mg/L) | 197 | 206 | 201.5 | - | - | - | 184.8 | 162.2 | 123.0 | 167.5 | 189.0 | 209.0 |
| Dissolved Organic Carbon (mM) | 0.31 | 0.47 | 0.39 | - | - | - | 0.41 | 0.41 | 0.93 | 0.94 | - | - |
| Temperature (oC) | 25.2 | 19.7 | 22.5 | - | - | - | 24.3 | 21.4 | 24.3 | 26.3 | 23.1 | 25.1 |
| Specific Conductivity (μS/cm) | 430.0 | 440.0 | 435.00 | - | - | - | 442.59 | 377.11 | 383.46 | 357.83 | 411.74 | 437.26 |
| pH | 8.6 | 7.9 | 8.3 | - | - | - | 8.1 | 8.6 | 9.0 | 9.0 | 8.5 | 8.8 |
| I (Ionic Strength ?) | 0.0753 | 0.0770 | 0.0761 | - | - | - | 0.0775 | 0.0660 | 0.0671 | 0.0626 | 0.0721 | 0.0765 |
| Dissolved Inorganic Carbon (mM) | 3.77 | 4.17 | 3.97 | - | - | - | 3.70 | 3.12 | 2.24 | 3.03 | 3.60 | 3.92 |
| pCO2 (μatm) | 388 | 2204 | 1295.9 | - | - | - | 1513.0 | 509.3 | 109.4 | 147.6 | 768.8 | 278.0 |
| Equilibrium CO2 | 12.59 | 14.78 | 13.68 | - | - | - | 13.00 | 14.08 | 12.95 | 12.21 | 13.53 | 12.64 |
| CO2 (μM) | 13.20 | 88.03 | 50.61 | - | - | - | 55.57 | 20.15 | 3.76 | 4.80 | 30.42 | 9.50 |
| Δ CO2 from Equilibrium | 0.609 | 73.247 | 36.93 | - | - | - | 42.57 | 6.07 | -9.19 | -7.41 | 16.88 | -3.14 |