Package 'CropWat'

Compute cycle period extend during the year

Description

Compute cycle period extend during the year

Usage

calc_isCycle(cp, DatesR, sowing_date = cp$sowing_date)

Arguments

cp	Crop parameters (See get_crop_params)
DatesR	A vector of continuous lubridate::Date If NULL, the calculation is limited to the crop cycle of the plant
sowing_date	Sowing date in format "MM-DD"

Value

A vector of logical of the crop cycle for each day of the year.

Examples

DatesR <- seq(as.Date("2010-03-01"), as.Date("2010-10-31"), by = "1 day")
isCycle <- calc_isCycle(get_crop_params("SB2023-soja"), DatesR)
plot(isCycle)

---

Compute crop parameters time series from crop parameters pivot points

Description

These functions compute the following parameters:

Usage

calc_Kc(cp, DatesR = NULL, sowing_date = cp$sowing_date)

calc_RAW(TAW, p)

calc_TAW(
  cp,
  AWC,
  soil_depth,
  DatesR = NULL,
  sowing_date = cp$sowing_date,
  root_depth = calc_root_depth(cp, soil_depth, DatesR, sowing_date)
)

calc_p(cp, DatesR = NULL, sowing_date = cp$sowing_date)

calc_root_depth(cp, soil_depth, DatesR = NULL, sowing_date = cp$sowing_date)

Arguments

cp	Crop parameters (See get_crop_params)
DatesR	A vector of continuous lubridate::Date If NULL, the calculation is limited to the crop cycle of the plant
sowing_date	Sowing date in format "MM-DD"
TAW	Total Available Water (mm). See calc_TAW
p	fraction of Readily Available Water time series. See calc_p
AWC	Available Water Capacity (mm)
soil_depth	Soil depth (m)
root_depth	Root depth time series (m). See calc_root_depth

Details

• Calc_Kc: crop coefficient $K_c$

• calc_p: critical depletion fraction $p=RAW/TAW$

• calc_root_depth: root depth in m

• calc_RAW: Readily Available Water (RAW) in mm

• calc_TAW: Total Available Water (TAW) in mm

For calc_TAW, parameters cp, year, and sowing_date are useless if root_depth is provided.

Value

A vector of the parameter for each day of the crop cycle or the period defined by DatesR.

Examples

# Compute Kc for the crop cycle
Kc <- calc_Kc(get_crop_params("SB2023-soja"))
plot(Kc, type = "l")

# Compute Kc for a given period (less than one year)
# with default sowing date defined in crop parameters
DatesR <- seq(as.Date("2010-03-01"), as.Date("2010-10-31"), by = "1 day")
Kc <- calc_Kc(get_crop_params("SB2023-soja"), DatesR = DatesR)
plot(Kc, type = "l")

# Compute Kc for a given period with user defined sowing date
Kc <- calc_Kc(get_crop_params("FAO-MAIZE"),
              DatesR = DatesR,
              sowing_date = "05-01")
plot(Kc, type = "l")

---

Create CropWat model input

Description

Create CropWat model input

Usage

CW_create_input(
  crop,
  DatesR,
  ETo,
  P,
  soil_depth,
  AWC,
  cp = get_crop_params(crop),
  sowing_date = cp$sowing_date
)

Arguments

crop	The code of the crop
DatesR	Simulation period (vector of lubridate::Date)
ETo	Potential Evaporation (mm/day)
P	Precipitation (mm/day)
soil_depth	Soil depth (m)
AWC	Available Water Capacity (mm)
cp	Crop parameters (See get_crop_params)
sowing_date	Sowing date in format "MM-DD"

Details

The crop cycle begins at the first matching sowing date in the simulation period. So, first time steps of simulation if are not in a crop cycle even if they occur during the crop cycle.

Value

A tibble::tibble containing the input times series.

Examples

# Import example climate dataset
data(ZH_3_clim)
str(ZH_3_clim)
# Selecting years 2010 and 2011
meteo <-
  ZH_3_clim[ZH_3_clim$Date >= as.Date("2010-01-01") & ZH_3_clim$Date <= as.Date("2011-12-31"), ]
# Create model input
cw_input <- CW_create_input("SB2023-soja",
                            DatesR = meteo$Date,
                            ETo = meteo$ETP,
                            P = meteo$Ptot,
                            soil_depth = 1.2,
                            AWC = 140)
str(cw_input)

plot(cw_input)

---

CropWat model state initiation

Description

CropWat model state initiation

Usage

CW_create_state(
  Dr = 0,
  cw_input = NULL,
  iTS = 1,
  isCycle = cw_input$isCycle[iTS],
  TAW = cw_input$TAW[iTS]
)

Arguments

Dr	Initial root zone depletion (-)
cw_input	Model input
iTS	Time step to pick up in cw_input for defining isCycle and TAW
isCycle	logical defining if the time step is in the crop cycle
TAW	Total Available Water (mm)

Value

A list with items:

• Dr: Root zone depletion (-)

• isCycle: logical indicating if the state stands during the crop cycle

• TAW: Total Available Water (m)

Examples

example(CW_create_input, "CropWat")

X <- CW_create_state(cw_input = cw_input)
str(X)

---

Retrieve the path of internal package data

Description

Retrieve the path of internal package data

Usage

CW_data(file)

Arguments

file

File name

Value

The path of the file stored in the package dataset

Examples

CW_data("crop_params.tsv")

---

Irrigation management functions

Description

• CW_irrig_0 simulates the absence of irrigation

• CW_irrig_Dr simulates an irrigation system that fills the soil's moisture depletion on a daily basis

Usage

CW_irrig_0(X, input, Dr)

CW_irrig_Dr(X, input, Dr)

Arguments

X	Model state at previous time step
input	Model input for the current time step
Dr	Current soil moisture depletion

Value

The amount of the daily irrigation (m)

Examples

CW_irrig_0()

example(CW_create_state, "CropWat")
CW_irrig_Dr(X, cw_input[1, ], 0.1)
CW_irrig_Dr(X, cw_input[100, ], 0.1)

---

Irrigation management function factory

Description

This function is a helper for generating irrigation management based on thresholds calculated from fixed ratio of RAW and/or TAW.

Usage

CW_irrig_fun_factory(
  RAW_ratio,
  TAW_ratio = 0,
  apply_Dr = FALSE,
  dates_irrig = NULL
)

Arguments

RAW_ratio	Ratio of RAW
TAW_ratio	Ratio of TAW
apply_Dr	When the threshold is reached, does the irrigation dose should fills the soil's moisture depletion?
dates_irrig	vector of lubridate::Date when irrigation occurs (By default, irrigation is applied during the crop cycle)

Value

A function which computes the irrigation dose for the current day.

Examples

# An irrigation management function which triggers an irrigation when
# Dr < 0.5 * RAW with a dose filling until 0.5 * RAW
fun_irrig_half_RAW <- CW_irrig_fun_factory(0.5)

fun_irrig_half_RAW

str(as.list(environment(fun_irrig_half_RAW)))

---

Run CropWat model for one time step

Description

Run CropWat model for one time step

Usage

CW_model(X, input, FUN_IRRIG = CW_irrig_Dr, is_irrigable_day = TRUE)

Arguments

X	Initial state (See CW_create_state)
input	Model input (See CW_create_input)
FUN_IRRIG	Irrigation management function
is_irrigable_day	logical TRUE if an irrigation is applicable for this time step

Value

A named numeric vector of class "CW_model" with items:

• Ks: Water stress coefficient (0-1, where 1 = no stress)

• ETc_adj: Adjusted crop evapotranspiration (mm/day)

• Dr: Root zone depletion at the end of the time step (mm)

• Ir: Irrigation dose for the current day (mm)

The returned value has an attribute "state" which contains the final state of the model at the end of the day (See CW_create_state).

Examples

data(ZH_3_clim)
meteo <-
  ZH_3_clim[ZH_3_clim$Date >= as.Date("2010-01-01") & ZH_3_clim$Date <= as.Date("2010-12-31"), ]
cw_input <- CW_create_input("SB2023-soja",
                            DatesR = meteo$Date,
                            ETo = meteo$ETP,
                            P = meteo$Ptot,
                            soil_depth = 1.2,
                            AWC = 140)
X0 <- CW_create_state(cw_input = cw_input)
X1 <- CW_model(X0, cw_input[1, ])
str(X1)

---

Run a simulation with the CropWat model

Description

Run a simulation with the CropWat model

Usage

CW_run_simulation(X, cw_input, FUN_IRRIG = CW_irrig_Dr)

Arguments

X	Initial state (See CW_create_state)
cw_input	Model input (See CW_create_input)
FUN_IRRIG	Irrigation management function

Value

A tibble::tibble with

Examples

example("CW_create_state", "CropWat")
cw_output <- CW_run_simulation(X, cw_input)
str(cw_output)

plot(cw_output)

---

Crop parameters

Description

• load_crop_params: load the parameters for all the crops

• get_crop_params: returns the parameters of a given crop

Usage

load_crop_params(file = CW_data("crop_params.tsv"))

get_crop_params(crop, crop_params = load_crop_params())

Arguments

file	Path of the table of crop parameters
crop	The code of the crop
crop_params	data.frame of crop parameters (See load_crop_params)

Details

The file to read should have the following columns and format:

• crop: crop code

• Lini: Length of initial stage of crop development

• Ldev: Length of crop development stage

• Lmid: Length of mid season

• Lend: Length of late season

• Kini: Initial Kc at the beginning of the crop cycle during Lini days (-)

• Kmax: Maximum Kc during Lmid day of the cycle (-)

• Kend: Final Kc at the end of the cycle (-)

• Zini: Initial root depth at the beginning of the crop cycle (m)

• Zend: Final root depth at the end of the crop cycle (m)

• p_ini: Initial fraction of readily available water (-)

• p_mid: Fraction of readily available water at Lmid day of the cycle (-)

• p_end: Final Initial fraction of readily available water at Lend day of the cycle (-)

• Yini: Yield response factor (Ky, not used yet)

• Ydev: Yield response factor (Ky, not used yet)

• Ymid: Yield response factor (Ky, not used yet)

• Yend: Yield response factor (Ky, not used yet)

• Ytot: Yield response factor (Ky, not used yet)

• h: crop height (m) (not used)

• sowing_date: Sowing date in format "MM-DD"

The default crop parameters provided in the package come from a variety of sources.

Crop names starting with "KURN-" or "FAO-" are imported from the CRO files provided with the CropWat 8.0 installation. "KURN-" are crop parameters calibrated at "Kurnool, Andhra Pradesh, India".

Crop names starting with "SB2023-" are crop parameters coming from a calibration performed on outputs of the AqYield model for the Aveyron catchment (Soutif-Bellenger, 2023).

Reference

Soutif-Bellenger, Myriam, Guillaume Thirel, Olivier Therond, et Jean Villerd. 2023. As Simple as Possible but Not Simpler?: The Case of Irrigation Modeling at Catchment Scale in Southwestern France. Irrigation Science 41 (5): 713‑36.

Value

A tibble::tibble, see details for the column formats.

Examples

# Get available crops in the package
cp <- load_crop_params()
cp$crop

str(cp)

# Get parameters for sugar beet from FAO
get_crop_params("FAO-SUGARBET")

---

Load CropWat v8.0 crop parameter CRO file

Description

Load CropWat v8.0 crop parameter CRO file

Usage

load_CW8_CRO(file)

Arguments

file	Path of the CRO file

Value

Crop parameters formatted as

Examples

load_CW8_CRO(system.file("extdata/TOMATO.CRO", package = "CropWat"))

---

Plot times series of CropWater inputs and outputs

Description

See CW_create_input and CW_run_simulation for examples.

Usage

## S3 method for class 'CW_TS'
plot(x, ...)

Arguments

x	Either CW_input or CW_output
...	Not used

Value

A ggplot object

---

Climate example dataset

Description

A data.frame with 3 columns:

• Date: the date

• Prtot: precipitation (mm/day)

• ETP: Potential evaporation (mm/day)

Usage

ZH_3_clim

Format

An object of class spec_tbl_df (inherits from tbl_df, tbl, data.frame) with 2922 rows and 3 columns.

---