Table 1.
Principal component analysis results of 19 bioclimatic variables.
| Variables | Eigenvectors | ||
|---|---|---|---|
| PC1 | PC2 | PC3 | |
| Annual mean temperature (Bio1) | − 0.0022 | 0.0024 | − 0.0284 |
| Mean diurnal range (Bio2) | 0.0006 | 0.0077 | 0.0012 |
| Isothermality (Bio3) | 0.0044 | 0.0032 | − 0.0040 |
| Temperature seasonality (Bio4) | − 0.1385 | 0.6772 | 0.3058 |
| Max. temperature of the warmest month (Bio5) | − 0.0036 | 0.0157 | − 0.0236 |
| Min. temperature of the coldest month (Bio6) | − 0.0011 | − 0.0109 | − 0.0346 |
| Temperature of annual range (Bio7) | − 0.0025 | 0.0265 | 0.0111 |
| Mean temperature of the wettest quarter (Bio8) | − 0.0062 | 0.0094 | 0.0227 |
| Mean temperature of the driest quarter (Bio9) | − 0.0032 | − 0.0009 | − 0.0212 |
| Mean temperature of the warmest quarter (Bio10) | − 0.0040 | 0.0103 | − 0.0242 |
| Mean temperature of the coldest quarter (Bio11) | − 0.0007 | − 0.0074 | − 0.0328 |
| Annual precipitation (Bio12) | 0.8275 | − 0.2352 | − 0.1132 |
| Precipitation of the wettest month (Bio13) | 0.1704 | 0.2482 | − 0.0910 |
| Precipitation of the driest month (Bio14) | 0.0008 | − 0.0221 | − 0.0215 |
| Precipitation seasonality (Bio15) | 0.0116 | 0.0378 | 0.0115 |
| Precipitation of the wettest quarter (Bio16) | 0.4209 | 0.6242 | − 0.2064 |
| Precipitation of the driest quarter (Bio17) | 0.0411 | − 0.0756 | − 0.1482 |
| Precipitation of the warmest quarter (Bio18) | 0.2902 | − 0.0766 | 0.8817 |
| Precipitation of the coldest quarter (Bio19) | 0.0604 | 0.1410 | − 0.1936 |
| Contribution rate | 94.60% | 3.20% | 1.30% |
| Cumulative contribution rate | 94.60% | 97.80% | 99.11% |