var

Condition variable

The following condition variables are currently coded in SWAT+. If a condition field is not listed in 'Additional fields used', you may leave it as null if field type is string or 0.0000 if field type is double/real.

Condition variable	Description	Additional fields used	Comments
w_stress	Water stress of the plant(s)	lim_const	If more than one plant is growing, the average stress will be used
n_stress	Nitrogen stress of the plant(s)	lim_const	If more than one plant is growing, the average stress will be used
p_stress	Phosphorus stress of the plant(s)	lim_const	If more than one plant is growing, the average stress will be used
phu_plant	Plant Heat Units since start of plant growth	lim_const	If more than one plant is growing, the Heat Units for the first one will be used
phu_base0	Heat Units since January 1 with a base temperature of 0 deg C	lim_const
precip_cur	Precipitation on the current day	lim_const
precip_next	Precipitation on the next day	lim_const
plant_gro	Plant growing	lim_var
plant_name_gro	Specific plant growing	plant.plt
days_plant	Days since last planting	lim_const
days_harv	Days since last harvest	lim_const
days_irr	Days since last irrigation	lim_const
days_act	Days since last action	lim_const
day_start	Days since first simulation day of the year	lim_const
slope	Slope of the HRU	lim_const
soil_water	Total soil water in the soil profile	lim_const, lim_var
jday	Julian day	lim_const
month	Month	lim_const
year_rot	Rotation year	lim_const
year_gro	Growth year of perennials	lim_const
year_cal	Calendar year	lim_const
year_seq	Sequential year of simulation	lim_const
cur_yrs_mat	Current years of maturity for perennial plants	lim_const
biomass	Above-ground biomass
leaf_area	Leaf Area Index	lim_const
gound_cov	Total ground cover (above-ground biomass and surface residue)
p_factor	USLE conservation practice factor
k_factor	USLE soil erodibility factor
hyd_soil_group	Hydrologic Soil Group
p_pet	Precipitation/PET ratio
p_lab_150	Soil labile phosphorus of first layer
soil_temp2	Soil temperature of second layer
soil_carbon	Soil organic carbon of first layer
tile_drained	The HRU is tile-drained
prob	Probability
prob_unif	Probability within a defined period assuming uniform distribution
channel_flo	Channel flow
tile_flo	Tile flow
irr_demand	Irrigation demand
aqu_dep	Aquifer depth below soil surface
land_use	Land use and management
tillage	Tillage system (name of tillage decision table)
plant_com	Plant is in the community
ch_order	Channel order
vol	Reservoir volume	lim_const, lim_var
res_inflo	Reservoir inflow	lim_const
wet_depth	Average depth of water on an impounded HRU (paddy)	lim_const
weirh	Paddy weir height	lim_const
vol_wet	Volume of water stored in a wetland	lim_const, lim_var