- widths (= c(300,700,1000,2000): Width of soil layers (in mm).
 
- clay (= 25): Clay percentage for each layer (in %).
 
- sand (= 25): Sand percentage for each layer (in %).
 
- om (= NA): Organic matter percentage for each layer (in %).
 
- bd (= 1.5): Bulk density for each layer (in g/cm3).
 
- rfc (= c(20,40,60,85)): Percentage of rock fragment content for each layer.