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Mean, minimum and maximum values of hydrological, meteorological, physical and chemical parameters in 2015
| Hydro- and meteorological parameters | Min. | Mean | Max | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Water flushing (m3 s−1) | −1.10 | 0.15 | 3.38 | ||||||
| Air temp. (°C) | −0.76 | 9.29 | 20.71 | ||||||
| Wind speed (m s−1) | 1.00 | 1.41 | 2.20 | ||||||
| Insolation (h) | 3.94 | 6.61 | 10.89 | ||||||
| Precipitati on (mm) | 1.25 | 5.76 | 9.82 | ||||||
| Physicochemical parameters | |||||||||
| Secchi depth (m) | 1.1 | 2.8 | 4.3 | ||||||
| Epilimnion | Metalimnion | Hypolimnion | |||||||
| Min. | Mean | Max | Min. | Mean | Max | Min. | Mean | Max | |
| Water temp. (°C) | 6.4 | 16.5 | 25.3 | 5.4 | 9.7 | 13.2 | 4.6 | 6.7 | 9.7 |
| Conductivity (μS cm−1) | 145.0 | 267 | 320.5 | 223.2 | 244.4 | 256.5 | 222.6 | 251.5 | 301.0 |
| pH | 8.3 | 8.6 | 9.0 | 7.3 | 8.2 | 9.0 | 7.2 | 7.6 | 8.6 |
| Chl-a conc. (μg l-1) | 3.6 | 4.8 | 6.5 | 3.3 | 11.2 | 32.8 | 2.9 | 3.8 | 5.0 |
| N-NH4 (μg l−1) | 20 | 120 | 400 | 10 | 113 | 276 | 10 | 99 | 198 |
| N-NO2 (μg l−1) | 5 | 6 | 9 | 14 | 35 | 90 | 5 | 14 | 90 |
| N-NO3 (μg l−1) | 50 | 280 | 810 | 200 | 373 | 820 | 340 | 624 | 838 |
| TN (μg l−1) | 450 | 920 | 1430 | 710 | 1101 | 1601 | 784 | 1228 | 1846 |
| ortho-P (μg l−1) | 10 | 20 | 50 | 9 | 17 | 31 | 9 | 9 | 10 |
| TP (μg l−1) | 30 | 120 | 470 | 34 | 135 | 417 | 34 | 156 | 324 |
| TN:TP | 1.6 | 12.9 | 31.2 | 3.0 | 11.5 | 27.4 | 3.4 | 13.4 | 36.2 |
Explained variation and significance tests of the variation partitioning that included three groups of variables – conditional (a, b, c) and simple effects (a+d+f+g, b+d+g+e, c+e+f+g) were tested
| Tested fraction | Explained variation (%) | F | p |
|---|---|---|---|
| a | 11.8 | 10.0 | 0.0002 |
| b | 6.2 | 7.1 | 0.0002 |
| c | 9.1 | 7.8 | 0.0002 |
| a + d + f + g | 21.8 | 14.5 | 0.0002 |
| b + d + g + e | 16.2 | 11.3 | 0.0002 |
| c + e + f + g | 18.8 | 12.0 | 0.0002 |
| a + b + c + d + e + f + g | 40.8 | 9.8 | 0.0002 |
Mean, minimum and maximum values of hydrological, meteorological, physical and chemical (Chl-a) parameters in 2014
| Hydro- and meteorological parameters | Min. | Mean | Max | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Water flushing (m3 s−1) | −3.71 | 0.86 | 6.79 | ||||||
| Air temp. (°C) | −0.09 | 9.07 | 17.33 | ||||||
| Wind speed (m s−1) | 1.19 | 1.85 | 4.66 | ||||||
| Insolation (h) | 3.34 | 5.35 | 8.91 | ||||||
| Precipitati on (mm) | 1.38 | 7.37 | 12.36 | ||||||
| Physicochemical parameters | |||||||||
| Secchi depth (m) | 1.2 | 1.9 | 2.8 | ||||||
| Epilimnion | Metalimnion | Hypolimnion | |||||||
| Min. | Mean | Max | Min. | Mean | Max | Min. | Mean | Max | |
| Water temp (°C) | 4.9 | 14.5 | 22.7 | 5.2 | 10.7 | 15.9 | 4.9 | 8.5 | 12.5 |
| Conductivity (μS cm−1) | 222.0 | 259.2 | 288.5 | 219.0 | 247.1 | 290.5 | 204.5 | 239.8 | 276.0 |
| pH | 8.2 | 8.7 | 9.2 | 7.8 | 8.2 | 8.5 | 7.7 | 7.8 | 8.2 |
| Chl-a conc. (μg l−1) | 3.1 | 7.2 | 13.9 | 3.7 | 7.4 | 9.9 | 4.5 | 6.1 | 9.8 |
Main morphological features of the studied Vrutci reservoir and characteristics of the catchment
| Characteristics of the reservoir | Value | Unit |
|---|---|---|
| Area | 1.92 | km2 |
| Volume | 40.2 × 106 | m3 |
| NPL (Normal Pool Level) | 621.3 | m a.s.l. |
| Max depth | 60 | m |
| Mean depth | 20.9 | m |
| Water retention time | 250 | days |
| Characteristi cs of the catchment | ||
| Area | 160 | km2 |
| Max altitude | 1544 | m a.s.l. |
| Mean altitude | 915 | m a.s.l. |