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Table 2 Environmental variables selected for the analysis and variance

From: Anopheles species associations in Southeast Asia: indicator species and environmental influences

Variable description Code Contribution
Spatial factor: spatial coordinates   
longitude * latitude XY 13%**
CT Abiotic factors: meteorology and topography   
Precipitation of Driest Month MINRAIN 5%**
Precipitation Seasonality (Coefficient of Variation) SEASONRAIN 5%**
Lowest number of rainy days in a month CMINRD0 7%**
Highest number of rainy days per month CMAXRD0 10%**
Mean number of rainy days per month CMEANRD0 5%**
Number of months with less 5 rainy days CNBML5DAY 11%**
Mean Temperature of Driest Quarter BIO_9 12%**
Precipitation of Warmest Quarter RAINWARMQ 5%**
Number of months with mean temp<20°C CNBMLESS20 6%**
Minimum temperature of the warmest month MAXMINT 7%**
Maximum temperature of the coldest month MINMAXT 9%**
Minimum temperature of the coldest month MINMINT 14%**
Annual Mean Temperature MEMET 10%**
Mean Diurnal Temperature Range DAYRANGET 12%**
Temperature Annual Range (bio5-bio6) BIO_7 14%**
Elevation above sea level (m) ALT 10%**
Compound topographic index*100 CTI2 11%**
Slope*100 SLOPE3 6%**
ND Biotic factors   
Mean value in buffer 3 km for annual NDWI from 2003 to 2005 men3WIAN 18%**
Mean value in buffer 3 km for annual NDVI from 2003 to 2005 men3VIAN 16%**
Range of value in buffer 3 km for annual NDVI from 2003 to 2005 ra3VIAN 5%**
Range of value in buffer 3 km for annual NDWI from 2003 to 2005 ra3WIAN 5%**
Mean value in buffer 3 km for maximum NDVI from 2003 to 2005 men3VIMAX 14%**
Minimum value in buffer 3 km for maximum NDVI from 2003 to 2005 min3VIMAX 17%**
Mean value in buffer 3 km for range NDVI from 2003 to 2005 men3VIRA 9%**
Minimum value in buffer 3 km for annual NDVI from 2003 to 2005 min3VIAN 17%**
Minimum value in buffer 3 km for annual NDWI from 2003 to 2005 min3WIAN 18%**
Maximum value in buffer 3 km for annual NDVI from 2003 to 2005 max3VIAN 13%**
Maximum value in buffer 3 km for annual NDWI from 2003 to 2005 max3WIAN 16%**
GC Land cover   
1 Forest (40,50,60,70,80,100,110,30) percentage area 3 km buffer (PCA) GFPCA1 10%**
1 Forested areas (40,50,60,70) (PCA) FOREST 6%**
40 Closed/ open broadleaved/ evergreen/ deciduous forest (100) (PCA) GDPCA40 6%**
30 Mosaic veg. (grassland/ shrub/ forest) (60%)/ cropland (35%) (PCA) MOSAIC 5%**
130 Closed/ open (broadleaved/ evergreen/ deciduous) shrub (PCA) SHRUB 8%**
5 Irrigated or shrimp farms (11) (PCA) SHRIMP 12%**
No. of Patches (NUMP) 1 forest (40,50,60,70,80,100,110,30) PATCHFOR 7%**
No. of Patches (NUMP) 1 forest (40,50,60,70) GCNUmP1 7%**
  1. Significant environmental variables and their contribution to the explanation of variance in the species dataset when used alone.