Table 1 Explanation of environmental variables and their contribution to the MaxEnt model
Category | Abbreviation | Variable | Excluded | Percentage contribution (%) |
|---|---|---|---|---|
Climate | EVP | Yearly average evaporation (mm) | Yes | – |
|  | GST | Yearly average ground surface temperature (°C) | Yes | – |
|  | PRS | Yearly average atmospheric pressure (hPa) | Yes | – |
| Â | RHU | Yearly average relative humidity (%) | No | 4.5 |
|  | SSD | Yearly average sunshine duration (h) | Yes | – |
|  | TEM | Yearly average air temperature (°C) | No | 7.9 |
| Â | WIN | Yearly average wind speed (m/s) | No | 35.3 |
| Â | PRE | Yearly cumulative precipitation (mm) | No | 11.6 |
Topographical | ALT | Altitude (m) | No | 6.3 |
| Â | NDVI | Normalized difference vegetation index | No | 14.8 |
Socioeconomic | GDP | Gross domestic product (104 RMB/person) | No | 0.2 |
| Â | NLI | Nighttime light index | No | 4.5 |
Livestock | Chicken_d | Chicken density (chickens/km2) | No | 0.7 |
|  | Duck_d | Duck density (ducks/km2) | Yes | – |
| Â | Cattle_d | Cattle density (cattles/km2) | No | 12.2 |
| Â | Goat_d | Goat density (goats/km2) | No | 1.2 |
| Â | Sheep_d | Sheep density (sheep/km2) | No | 0.8 |
|  | Pig_d | Pig density (pigs/km2) | Yes | – |