Variable Measurement units Data sources
Road length km Esri Data and Maps: https://www.arcgis.com/home/item.html?id=83535020ce154bd5a498957c159e3a99
Road density km-1 Esri Data and Maps: https://www.arcgis.com/home/item.html?id=83535020ce154bd5a498957c159e3a99
Small ruminants density
head/km2
For China: FAO Gridded Livestock of the World (Robinson et al., 2010) http://www.fao.org/geonetwork/srv/en/main.home For Kazakhstan: national survey data described below
Cattle density head/km2 FAO Gridded Livestock of the World (Robinson et al., 2010) http://www.fao.org/geonetwork/srv/en/main.home
Population density
person/km2
Gridded Population of the World (GPW), v4 (Center for International Earth Science Information Network, 2018) https://sedac.ciesin.columbia.edu/data/set/gpw-v4-population-count-rev11/data-download
Elevation m USGS EarthExplorer: https://earthexplorer.usgs.gov/
Annual mean temperature
°Сx10
WorldClim 2 (Fick and Hijmans, 2017) https://worldclim.org/
Annual precipitation
mm
WorldClim 2 (Fick and Hijmans, 2017) https://worldclim.org/
Maximum green vegetation fraction proportion Broxton et al., 2014; https://archive.usgs.gov/archive/sites/landcover.usgs.gov/green_veg.html