RUFAS.routines.field.crop.water_dynamics module

class RUFAS.routines.field.crop.water_dynamics.WaterDynamics(crop_data: CropData | None = None, cumulative_evapotranspiration: float = 0.0)

Bases: object

Manages water dynamics related to crop growth, including water uptake, transpiration, and evaporation.

Parameters

crop_dataOptional[CropData], optional

An instance of CropData containing crop specifications and states relevant to water dynamics. If not provided, a default instance with generic parameters is used.

cumulative_evapotranspirationfloat, default 0.0

Total water lost to evapotranspiration by the plant during the growing season (mm).

Attributes

dataCropData

Reference to the CropData instance used to access and modify water-related parameters and states for the crop.

cumulative_evapotranspirationfloat

Total water lost to evapotranspiration by the plant during the growing season (mm).

__init__(crop_data: CropData | None = None, cumulative_evapotranspiration: float = 0.0)

cycle_water(evaporation: float, transpiration: float, potential_evapotranspiration: float) → None

Executes the daily cycling of water between the plants, soil, and environment.

Parameters

evaporationfloat

Evaporation on a given day (mm).

transpirationfloat

Transpiration on a given day (mm).

potential_evapotranspirationfloat

Potential evapotranspiration on a given day (mm).

Notes

This method updates cumulative sums that are used to keep the water deficiency factor updated.

evaporate_from_canopy(potential_evapotranspiration: float) → float

Evaporates water from the canopy.

Parameters

potential_evapotranspirationfloat

Evapotranspirative demand on the field on the current day (mm)

Returns

float

Amount evaporated from canopy (mm)

References

SWAT Theoretical documentation section 2:2.3.1

Notes

This method evaporates water from the crop’s canopy until either 1) there is no more water in the canopy or 2) there is no more evapotranspirative demand. It then returns the amount of water that was evaporated from the canopy.

set_maximum_transpiration(potential_evapotranspiration_adjusted: float) → None

Sets the maximum transpiration based on the adjusted potential evapotranspiration of this day.

Parameters

potential_evapotranspiration_adjustedfloat

Evapotranspirative demand remaining after evaporating water in the canopy (mm)

References

SWAT Theoretical documentation section 2:2.3.2

static _determine_maximum_transpiration(leaf_area_index: float, potential_evapotranspiration_adjusted: float) → float

Calculates the maximum transpiration for a given day.

Parameters

leaf_area_indexfloat

Leaf area index of the plant (unitless).

potential_evapotranspiration_adjustedfloat

Potential evapotranspiration adjusted for evaporation of free water from the canopy (mm).

Returns

float

Maximum transpiration (mm).

References

SWAT 2:2.3.5, 6

static _determine_evapotranspiration(evaporation: float, transpiration: float) → float

Calculate evapotranspiration as the sum of evaporation and transpiration.

Parameters

evaporationfloat

Evaporation (mm).

transpirationfloat

Transpiration (mm).

Returns

float

Total evapotranspiration (mm).

static _determine_water_deficiency(cumulative_evapotranspiration: float, cumulative_potential_evapotranspiration: float) → float

Calculate water deficiency factor.

Parameters

cumulative_evapotranspirationfloat

Annual evapotranspiration (mm).

cumulative_potential_evapotranspirationfloat

Maximum annual evapotranspiration (mm).

Returns

float

Water deficiency factor (unitless).

References

SWAT 5:3.3.2