Table 1
Characteristics of the studied lakes (based on: Jańczak 1996; Pełechaty, Pukacz 2006; Pełechaty et al. 2007)
| Unit | Jasne | Karskie | Malcz | Męckie | Niesłysz | Pierwsze | Złoty Potok | |
|---|---|---|---|---|---|---|---|---|
| Geographical coordinates | - | 52°17'7"N 15°03'06"E | 52°55'4"N 15°04'8"E | 52°21'1”N 15°13'3"E | 52°22'0"N 15°11'2"E | 52°13'9"N 15°23'8"E | 52°23'11”N 15°09'18"E | 52°13'0"N 15°22'5"E |
| Surface area | ha | 15.1 | 150 | 36.2 | 40.9 | 486.2 | 19.3 | 32.8 |
| Mean depth | m | 4.3 | 6.2 | 3.4 | 9.2 | 7.8 | 4.7 | 5.9 |
| Max depth | m | 9.5 | 17.6 | 7.3 | 22.7 | 34.7 | 10.7 | 13.7 |
| Lake type | - | outflow | flow | no flows | flow | no flows | no flows | no flows |
| Stratification | - | incomplete | complete | incomplete | complete | complete | incomplete | complete |
| SD visibility | m | 3 | 3.1 | 3.8 | 6.5 | 4.2 | 5.4 | 4.3 |
| C. tomentosa sampling depth | m | 3 | 3 | 3 | 2 | 2 | ||
| C. globularis sampling depth | m | 4 | 3 | 3 | 4 | 4 |
Figure 1
Lake-to-lake variability of charophyte dry weight. The dashed line points at the lakes in which both species occurred. Each box-whiskers plot n = 30 (10 individuals × 3 sites). Abbreviations on the horizontal scale indicate the name of the lake (J – Jasne, K – Karskie, M – Męckie, Ma -Malcz, N – Niesłysz, P – Pierwsze, Z – Złoty Potok) slashed with the species name (Cg – Chara globularis, Ct – Chara tomentosa). The colors indicate species (gray is for C. globularis, white is for C. tomentosa). Different letters (lower case – C. globularis, uppercase – C. tomentosa) indicate significant (P < 0.05) lake-to-lake differences.
Figure 2
Lake-to-lake variability of calcium carbonate content in charophyte dry weight. The dashed line points at the lakes in which both species occurred. Each box-whiskers plot n = 30 (10 individuals X 3 sites). Abbreviations on the horizontal scale indicate the name of the lake (J – Jasne, K – Karskie, M – Męckie, Ma -Malcz, N – Niesłysz, P – Pierwsze, Z – Złoty Potok) slashed with the species name (Cg – Chara globularis, Ct – Chara tomentosa). The colors indicate species (gray is for C. globularis, white is for C. tomentosa). Different letters (lower case – C. globularis, uppercase – C. tomentosa) indicate significant (P < 0.05) lake-to-lake differences.
Figure 3
PCA output for physicochemical water properties at all the study sites. The symbols indicate particular lakes. The colors indicate species (gray is for C. globularis, white is for C. tomentosa).
Table 2
Means and standard deviations of the physicochemical water properties significantly differentiating the investigated lakes. Results of ANOVA tests (F and p-values are indicated; degrees of freedom: 6 and 23). Results of post hoc analyses are indicated by means of capital letters.
| ANOVA | Jasne (n = 6) | Karskie (n = 6) | Malcz (n = 3) | Męckie (n = 6) | Niesłysz (n = 3) | Pierwsze (n = 3) | Złoty Potok (n = 3) | |
|---|---|---|---|---|---|---|---|---|
| O2 (mg l-1) | F = 31.4 P < 0.001 | A 6.0 ± 0.1 | BCD 7.4 ± 0.3 | A 5.3 ± 0.1 | BCD 7.4 ± 0.2 | C 8.2 ± 0.6 | D 7.0 ± 0.2 | D 7.0 ± 0.2 |
| Alkalinity (mval l-1) | F = 345.8 P < 0.001 | A 1.6 ± 0.1 | B 2.8 ± 0.0 | CD 1.9 ± 0.06 | C 1.7 ± 0.1 | D 1.9 ± 0.0 | E 1.2 ± 0.1 | F 2.2 ± 0.6 |
| Conductivity (µS cm-1) | F = 803.3 P < 0.001 | A 304 ± 13.4 | B 590 ± 11.9 | C 266 ± 6.6 | C 263 ± 3.7 | A 318 ± 18.5 | D 158 ± 5.8 | A 332 ± 5.6 |
| Ca2+ (mg l-1) | F = 1512.1 P < 0.001 | A 47.4 ± 1.4 | B 77.8 ± 1.2 | C 38.3 ± 0.3 | C 40.4 ± 0.5 | D 44.0 ± 0.2 | E 22.6 ± 0.2 | A 49.7 ± 1.0 |
| Mg2+ (mg l-1) | F = 61.3 P < 0.001 | A 2.9 ± 0.6 | B 9.6 ± 1.4 | A 2.7 ± 0.3 | A 2.2 ± 0.4 | C 5.3 ± 1.0 | A 2.1 ± 0.5 | C 5.9 ± 0.2 |
| Hardness (°dH) | F = 1433.5 P < 0.001 | A 7.3 ± 0.2 | C 13.1 ± 0.2 | B 6.0 ± 0.1 | B 6.2 ± 0.1 | A 7.4 ± 0.2 | D 3.7 ± 0.1 | E 8.3 ± 0.1 |
Table 3
Significant correlations between the dry weight and calcium carbonate content of each charophyte species and the habitat characteristics of the study sites. For each characteristic n = 15 (DW and % CaCO3 were represented by mean of 10). The asterisks (*) indicate the significance level (< 0.05, < 0.01, < 0.001, respectively)
| Chara globularis | Chara tomentosa | |||
|---|---|---|---|---|
| Dry weight | % CaCO3 | Dry weight | % CaCO3 | |
| Temperature | 0.61* | |||
| -0.53* | ||||
| Conductivity | -0.63** | |||
| Alkalinity | -0.59* | -0.59* | ||
| Ca2+ | -0.88*** | |||
| Mg2+ | -0.55* | |||
| Hardness | -0.75*** | |||
| TP | 0.73** | |||
| Sampling depth | 0.69** | |||
| % bottom cover | 0.72** | |||
| No. of species | -0.58* | |||