Table 1. Analysis of covariance for log10 phytoplankton species richness.
Source | Type III sum of squares | df | Mean square | F | Significance level |
---|---|---|---|---|---|
Corrected model | 114.734 | 3 | 38.245 | 364.149 | <0.001 |
Intercept | 178.164 | 1 | 178.164 | 1696.395 | <0.001 |
CODE | 0.001 | 1 | 0.001 | 0.007 | 0.934 |
Log10 AREA | 24.340 | 1 | 24.340 | 231.758 | <0.001 |
CODE × log10 AREA | 0.235 | 1 | 0.235 | 2.236 | 0.136 |
Error | 39.805 | 379 | 0.105 | ||
Total | 774.272 | 383 | |||
Corrected total | 154.539 | 382 |
log10 lake area (AREA, km2) is the covariate, and the data is coded as either 0 (natural aquatic ecosystems) or 1 (experimental ecosystems). R2 = 0.742 (adjusted R2 = 0.740).