TABLE 1.
Physicochemical variables of the different sampling sitesa
| Sampling site | pH | Conductivity (μS cm−1) | Carbonate alkalinity (mmol−1) | DOC (mg liter−1) | Ptot (μg liter−1) | O2 (mg liter−1) | TSS (mg liter−1) | Chl a (μg liter−1) | NH4-N (μg liter−1) | NO3-N (μg liter−1) | Secchi depth (cm) | Temp (°C) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 5 | 8.6 (8.1–8.9) | 1,975 (1,500–3,000) | 11.5 (7.0–17.5) | 18.5 (12.0–26.0) | 36 (17–87) | 8.5 (5.2–11.6) | 68.9 (18.1–130) | 7.8 (1.8–22.8) | 39 (10–86) | 115 (47–154) | 65 (8–137) | 17.8 (3.4–26.9) |
| 24 | 8.8 (8.6–8.9) | 1,850 (1,500–2,200) | 11.9 (10.6–12.8) | 12.5 (11.5–14.8) | 30 (13–51) | 9.9 (7.9–12.6) | NA | 8.8 (1.1–20.2) | 13 (2–34) | 82 (14–176) | 31 (8–95) | 16.3 (3.8–24.9) |
| 29 | 8.3 (7.4–8.8) | 1,625 (800–2,600) | 10.2 (5.7–12.5) | 9.8 (5.8–15.2) | 62 (28–112) | 7.1 (1.3–11.9) | NA | 8.1 (1.7–17.7) | 56 (6–411) | 116 (37–340) | 44 (12–120) | 16.0 (4.6–25.0) |
| 36 | 8.4 (8.1–8.6) | 2,113 (1,600–3,000) | 12.7 (8.2–17.5) | 21.8 (15.6–26.8) | 31 (17–64) | 7.9 (5.2–10.5) | 24.1 (11.7–88.7) | 5.4 (1.8–12.2) | 12 (1–54) | 86 (10–146) | 90 (12–137) | 18.3 (3.4–26.9) |
| ZL | 9.4 (8.7–9.9) | 7,057 (1,100–29,600) | 38.0 (5.5–201) | 110.7 (17.5–431) | 627 (40–3,120) | 8.3 (1.9–16.8) | 8,117 (5–75,250) | 102.8 (0.2–476) | NA | NA | 14 (2–45) | 14.6 (0.7–24.3) |
| US | 9.1 (8.7–9.6) | 3,550 (2,100–6,500) | 31.6 (8.0–71.1) | 49.5 (32.0–79.8) | 89 (24–245) | 8.1 (5.2–12.5) | NA | 23.9 (1.4–186) | NA | NA | 16 (2–45) | 16.0 (2.3–25.6) |
a
Data are mean values, with minimum and maximum values in parentheses. DOC, dissolved organic carbon; Ptot, total phosphorus; TSS, total suspended solids; Chl a, chlorophyll a; NA, not analyzed.