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medfate (version 0.8.2)

spwb_day: Soil-plant water balance for a single day

Description

Function spwb_day performs water balance for a single day.

Usage

spwb_day(x, soil, date, tmin, tmax, rhmin, rhmax, rad, wind, 
        latitude, elevation, slope, aspect, prec, runon = 0.0)

Arguments

x

An object of class spwbInput.

soil

A list containing the description of the soil (see soil).

date

Date as string "yyyy-mm-dd".

tmin, tmax

Minimum and maximum temperature (in degrees Celsius).

rhmin, rhmax

Minimum and maximum relative humidity (in percent).

rad

Solar radiation (in MJ/m2/day).

wind

Wind speed (in m/s).

prec

Precipitation (in mm).

latitude

Latitude (in degrees). Required when using the 'Sperry' transpiration mode.

elevation, slope, aspect

Elevation above sea level (in m), slope (in degrees) and aspect (in degrees from North). Required when using the 'Sperry' transpiration mode.

runon

Surface water amount running on the target area from upslope (in mm).

Value

An object (a list) of class spwb_day with the following elements:

  • "cohorts": A data frame with cohort information, copied from spwbInput.

  • "WaterBalance": A vector of water balance components (rain, snow, net rain, infiltration, ...) for the simulated day, equivalent to one row of 'WaterBalance' object given in spwb.

  • "Soil": A data frame with results for each soil layer:

    • "SoilEvaporation": Water evaporated from the soil surface (in mm).

    • "HydraulicInput": Water entering each soil layer from other layers, transported via plant hydraulic network (in mm) (only for transpirationMode = "Sperry").

    • "HydraulicOutput": Water leaving each soil layer (going to other layers or the transpiration stream) (in mm) (only for transpirationMode = "Sperry").

    • "PlantExtraction": Water extracted by plants from each soil layer (in mm).

    • "psi": Soil water potential (in MPa).

  • "EnergyBalance": When using the 'Sperry' transpiration mode, the model performs energy balance of the stand and 'EnergyBalance' is returned (see transp_transpirationSperry).

  • "Plants": A data frame of results for each plant cohort (see transp_transpirationGranier or transp_transpirationSperry).

  • "RhizoPsi": Minimum water potential (in MPa) inside roots, after crossing rhizosphere, per cohort and soil layer.

  • "ExtractionInst": Water extracted by each plant cohort during each time step.

  • "PlantsInst": A list with instantaneous (per time step) results for each plant cohort (see transp_transpirationSperry).

Details

Detailed model description is available in the vignettes section. The model using 'Granier' transpiration mode is described in De Caceres et al. (2015). Simulations using the 'Sperry' transpiration mode are computationally much more expensive.

References

De C<U+00E1>ceres M, Mart<U+00ED>nez-Vilalta J, Coll L, Llorens P, Casals P, Poyatos R, Pausas JG, Brotons L. (2015) Coupling a water balance model with forest inventory data to predict drought stress: the role of forest structural changes vs. climate changes. Agricultural and Forest Meteorology (doi:10.1016/j.agrformet.2015.06.012).

See Also

spwbInput, spwb, plot.spwb_day, spwb_ldrOptimization, forest

Examples

Run this code
# NOT RUN {
#Load example daily meteorological data
data(examplemeteo)

#Load example plot plant data
data(exampleforest)

#Default species parameterization
data(SpParamsMED)

#Initialize control parameters
control = defaultControl()

#Initialize soil with default soil params (2 layers)
examplesoil = soil(defaultSoilParams(2), W=c(0.5,0.5))


#Simulate one day only
x1 = forest2spwbInput(exampleforest,examplesoil, SpParamsMED, control)
d = 100
sd1<-spwb_day(x1, examplesoil, rownames(examplemeteo)[d],  
             examplemeteo$MinTemperature[d], examplemeteo$MaxTemperature[d], 
             examplemeteo$MinRelativeHumidity[d], examplemeteo$MaxRelativeHumidity[d], 
             examplemeteo$Radiation[d], examplemeteo$WindSpeed[d], 
             latitude = 41.82592, elevation = 100, slope=0, aspect=0,
             prec = examplemeteo$Precipitation[d])

#Initialize soil with default soil params (2 layers)
examplesoil2 = soil(defaultSoilParams(2))

#Switch to 'Sperry' transpiration mode
control$transpirationMode="Sperry"


#Simulate one day only
x2 = forest2spwbInput(exampleforest,examplesoil2, SpParamsMED, control)
d = 100
sd2<-spwb_day(x2, examplesoil2, rownames(examplemeteo)[d],
             examplemeteo$MinTemperature[d], examplemeteo$MaxTemperature[d], 
             examplemeteo$MinRelativeHumidity[d], examplemeteo$MaxRelativeHumidity[d], 
             examplemeteo$Radiation[d], examplemeteo$WindSpeed[d], 
             latitude = 41.82592, elevation = 100, slope=0, aspect=0,
             prec = examplemeteo$Precipitation[d])

#Plot plant transpiration (see function 'plot.swb.day()')
plot(sd2)

# }

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