Table 1.
Variation in the environmental variables within the three drainage basins. Variables are given as mean, min, max and standard deviation (SD)
| Iijoki (n = 20) | Koutajoki (n = 20) | Tenojoki (n = 30) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean | Min | Max | SD | Mean | Min | Max | SD | Mean | Min | Max | SD | |
| Deciduous trees (%) | 35 | 5 | 80 | 19 | 44 | 10 | 75 | 15 | 99.9 | 98 | 100 | 0.4 |
| Shading (%) | 34 | 10 | 70 | 20 | 44 | 5 | 85 | 26 | 16 | 0 | 55 | 14 |
| Velocity (m/s) | 0.40 | 0.16 | 0.73 | 0.16 | 0.51 | 0.21 | 1.02 | 0.19 | 0.37 | 0.14 | 0.58 | 0.11 |
| Depth (cm) | 24 | 16 | 35 | 7 | 25 | 10 | 46 | 10 | 19 | 13 | 33 | 19 |
| Width (cm) | 304 | 100 | 650 | 131 | 299 | 78 | 1200 | 266 | 574 | 88 | 2400 | 506 |
| Macrophytes (%) | 44 | 1 | 78 | 23 | 11 | 0 | 43 | 15 | 4 | 0 | 16 | 4 |
| Sand (%) | 10 | 0 | 49 | 12 | 11 | 0 | 73 | 18 | 1 | 0 | 22 | 1 |
| Gravel (%) | 6 | 0 | 37 | 9 | 9 | 0 | 30 | 8 | 2 | 0 | 25 | 5 |
| Pebble (%) | 10 | 0 | 55 | 14 | 33 | 0 | 64 | 19 | 15 | 1 | 65 | 12 |
| Cobble (%) | 29 | 2 | 53 | 14 | 26 | 0 | 61 | 16 | 45 | 10 | 81 | 20 |
| Boulder (%) | 44 | 0 | 82 | 25 | 20 | 0 | 92 | 24 | 37 | 1 | 83 | 22 |
| pH | 6.4 | 5.7 | 6.9 | 0.3 | 7.3 | 6.8 | 7.9 | 0.3 | 6.6 | 6.3 | 6.7 | 0.1 |
| Conductivity (mS/m) | 2.09 | 1.50 | 3.10 | 0.41 | 6.99 | 2.75 | 17.50 | 3.75 | 1.83 | 1.20 | 2.40 | 0.32 |