Table 1.
Features that imposed selection and dispersal limitation in the Paraná fluvial system during different hydrological phases based on the model selection for βNTI and RCbray analysis.
| Hydrological phase | Features imposing selection | Features imposing dispersal limitation |
|---|---|---|
| Low water (LW) | PCA1: DO, pH, CDOM molecular weight | NA |
| PCA3: unmeasured abiotic variable | ||
| PCA4: unmeasured abiotic variable | ||
| Low water + sedimentological pulse (LWs) | PCA1: SPR, nitrate | NA |
| PCA3: pH + unmeasured abiotic variable | ||
| PCA11: pH, CDOM molecular weight | ||
| High water (HW) | PCA1: conductivity, DO, CDOM molecular weight | PCA2 |
| PCA3 | ||
| Extraordinary high water (eHW) | PCA1: CDOM molecular weight, CDOM concentration | NA |
| PCA5: SPR | ||
| PCA6: SPR |
The PCA axes retained during model selection for βNTI were considered as imposing selection and those significant for RCbray as imposing dispersal limitation. Within each PCA significant for βNTI, strong loading was considered as a measure or unmeasured variable imposing selection. Loading values for each PCA axes are presented in Supplementary Table S4.
DO dissolved oxygen, SPR soluble reactive phosphorous, CDOM chromophoric dissolved organic matter, NA indicated that nonsignificant PCA axes were retained in RCbray model selection.