Table 1.
Mean values for water quality parameters by ecoregion (±SE). Abbreviations for ecoregions are as follows: NAP = Northern Appalachians, SAP = Southern Appalachians, CPL = Coastal Plains, TPL = Temperate Plains, NPL = Northern Plains, SPL = Southern Plains, UMW = Upper Midwest, WMT = Western Mountains, XER = Xeric.
| Secchi Depth (m) | TN (mg L−1) | TP (μg L−1) | Temp (°C) | DOC (mg L−1) | Index Site Depth (m) | Area:Depth | |
|---|---|---|---|---|---|---|---|
| NAP | 2.9 (± 0.2) | 0.41 (± 0.03) | 25 (± 3) | 23.2 (± 0.6) | 4.58 (± 0.21) | 9.57 (± 0.98) | 0.15 (± 0.02) |
| SAP | 2.0 (± 0.1) | 0.57 (± 0.05) | 58 (± 9) | 25.1 (± 0.3) | 3.69 (± 0.21) | 8.88 (± 0.73) | 0.17 (± 0.02) |
| CPL | 1.0 (± 0.1) | 1.24 (± 0.12) | 125 (± 24) | 28.1 (± 0.2) | 8.41 (± 0.65) | 3.92 (± 0.29) | 0.63 (± 0.13) |
| TPL | 1.2 (± 0.1) | 1.64 (± 0.10) | 173 (± 19) | 24.8 (± 0.5) | 9.43 (± 0.48) | 5.39 (± 0.35) | 0.27 (± 0.03) |
| NPL | 1.2 (± 0.1) | 2.92 (± 0.69) | 332 (± 68) | 20.4 (± 0.4) | 18.50 (± 1.50) | 5.55 (± 0.90) | 0.33 (± 0.05) |
| SPL | 1.0 (± 0.3) | 2.59 (± 0.58) | 245 (± 47) | 25.2 (± 0.5) | 19.99 (± 6.20) | 4.28 (± 0.34) | 0.38 (± 0.04) |
| UMW | 2.3 (± 0.1) | 0.87 (± 0.06) | 42 (± 4) | 22.9 (± 0.3) | 8.66 (± 0.38) | 8.25 (± 0.51) | 0.14 (± 0.01) |
| WMT | 3.6 (± 0.3) | 0.42 (± 0.04) | 52 (± 7) | 17.8 (± 0.3) | 4.09 (± 0.31) | 13.41 (± 1.08) | 0.12 (± 0.01) |
| XER | 1.9 (± 0.2) | 0.77 (± 0.10) | 130 (± 18) | 20.4 (± 0.4) | 5.91 (± 0.53) | 9.66 (± 1.08) | 0.25 (± 0.03) |