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. 2013 Oct 14;8(10):e76308. doi: 10.1371/journal.pone.0076308

Table 1. Environmental predictors used to derive species distribution models.

Variable theme Variable name Variable definition
Topography *AspNS Aspect  =  sin (rad (aspect))
†AspEW Aspect  =  cos (rad (aspect))
Climate ‡Isoth Isothermality %
TAR Temperature Annual Range
MTDQ Mean Temperature of Driest Quarter
MTCQ Mean Temperature of Coldest Quarter
RainSeasCV Precipitation Seasonality (Coefficient of Variation)
RainCQ Precipitation Coldest Quarter (mm)
Land-cover BLW Broadleaf woodland
ConW Coniferous woodland
AR Arable
GrassImp Improved grassland
GrassSN Semi-natural grassland
MHB Mountain, heath, bog
SW Saltwater
FW Freshwater
Coast Coastal
UrbGar Built-up areas and gardens
Pesticides Pest Average number of risk hectares
*

AspNS  =  sine (radiant [aspect angle in degree]); †AspEW  =  cosine (radiant [aspect angle in degree]); ‡Isothermality %  =  Mean Diurnal Range (MDR)/Temperature Annual Range (TAR); where MDR  =  Mean of monthly (max temp – min temp)); TAR  =  Max Temperature of Warmest Month – Min Temperature of Coldest Month. Isothermality is a quantification of how large the day-to-night temperature oscillation is in comparison to the summer-to-winter oscillation. A value of 100 would represent a site where the diurnal temperature range is equal to the annual temperature range. A value of 50 would indicate a location where the diurnal temperature range is half of the annual temperature range.