Table 1.
Multiple linear regression analyses on the effects of temperature (°C) and absorbance (water color, a 420, m−1) on response variables (lm[response variable ~ water temperature + absorbance]). N indicates the number of lakes included (differ because of data availability, see methods) and LN that the response variable was ln‐transformed prior to analysis. D is the direction of change, zeros indicating nonsignificant relationships. A positive skewness in length/age represents a higher proportion of small/young individuals. (*p < 0.05, **p < 0.01, ***p < 0.001, nonsignificant results in bold). In no case was there a significant interaction between temperature and absorbance
| Response variable | Temperature | Absorbance | R 2 | ||
|---|---|---|---|---|---|
| D | F | D | F | ||
|
Fish biomass production (LN) N = 46 |
− | F(1,43) = 5.27* | − | F(1,43) = 10.59** | 0.29 |
|
Population biomass (LN) N = 52 |
− | F(1,49) = 6.01* | 0 | F (1,49) = 2.96 | 0.16 |
|
Population abundance (LN) N =52 |
0 | F (1,49) = 2.18 | 0 | F (1,49) = 0.99 | 0.06 |
|
Mean length (LN) N = 49 |
− | F(1,46) = 8.51** | 0 | F (1,46) = 1.41 | 0.19 |
|
Skewness (positive) in length N = 49 |
+ | F(1,46) = 16.76*** | 0 | F (1,46) = 0.08 | 0.27 |
|
Mean predicted age (LN) N = 46 |
− | F(1,43) = 14.62*** | + | F(1,43) = 4.23* | 0.29 |
|
Skewness (positive) in age N = 42 |
+ | F(1,39) = 15.91*** | 0 | F (1,39) = 0.0084 | 0.29 |
|
Length‐at‐age 1 (LN) N = 49 |
+ | F(1,45) = 4.83* | − | F(1,45) = 7.48** | 0.20 |
|
Length‐at‐age 6 (LN) N = 49 |
0 | F (1,45) = 0.05 | − | F(1,45) = 28.29*** | 0.39 |
|
Length‐specific growth rate at 170 mm body length (LN) N = 49 |
0 | F (1,46) = 0.61 | − | F(1,46) = 6.86* | 0.15 |