soils.sol

This file contains the physical soil properties.

The structure of the file soils.sol is different than that of most other SWAT+ input files. Depending on the number of soil layers, the file contains two to ten lines per soil. The first line for each soil specifies the variables that apply to the entire soil profile (see first table below). The remaining soil variables are layer-specific and are specified in one line per layer starting one line below the general soil variables (see second table below). The figure below illustrates the structure of a soils.sol file with three soils. Please note that due to space restrictions not all layer-specific variables are included.

Example of a soils.sol file with three soils

Field	Description	Type	Unit	Default	Range
name	Name of the soil	string	n/a
nly	Number of layers in the soil	integer	none
hyd_grp	Hydrologic soil group of the soil	string	n/a
dp_tot	Maximum rooting depth	real	mm
anion_excl	Fraction of porosity (void space) from which anions are excluded	real	fraction
perc_crk	Potential or maximum crack volume of the soil profile expressed as a fraction of the total soil volume	real
texture	Texture of the soil	string	n/a

Field	Description	Type	Unit	Default	Range
dp	Depth from the soil surface to the bottom of the soil layer	real
bd	Moist bulk density of the soil layer	real
awc	Available water capacity of the soil layer	real
soil_k	Saturated hydraulic conductivity of the soil layer	real
carbon	Organic carbon content of the soil layer	real
clay	Clay content of the soil layer	real
silt	Silt content of the soil layer	real
sand	Sand content of the soil layer	real
rock	Rock fragment content of the soil layer	real
alb	Moist soil albedo of the top layer	real
usle_k	USLE equation soil erodibility (K) factor of the top layer	real
ec	Electrical conductivity of the soil layer	real
caco3	Calcium carbonate (CaCO3) content of the soil layer	real
ph	pH value of the soil layer	real