LWFBrook90R: make_seasLAI – R documentation

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make_seasLAI

Construct the seasonal course of leaf area index from parameters

Description

A daily sequence of leaf area index is derived from maximum and minimum values, dates and shape parameters using different methods.

Usage

make_seasLAI(
  method = "b90",
  year,
  maxlai,
  winlaifrac = 0,
  budburst_doy = 121,
  leaffall_doy = 279,
  emerge_dur = 28,
  leaffall_dur = 58,
  shp_optdoy = 220,
  shp_budburst = 0.5,
  shp_leaffall = 10,
  lai_doy = c(1, 121, 150, 280, 320, 365),
  lai_frac = c(0, 0, 0.5, 1, 0.5, 0)
)

Arguments

`method`	Name of method for generating the sequence. Must be one of "b90", "linear", "Coupmodel".
`year`	Vector of years to be returned.
`maxlai`	Maximum leaf are index.
`winlaifrac`	Fraction of `maxlai` during winter (ignored when `method = 'linear'`).
`budburst_doy`	Budburst day of year (ignored when `method = 'linear'`).
`leaffall_doy`	Day of year when leaf fall begins (ignored when `method = 'linear'`).
`emerge_dur`	Number of days from budburst until maximum leaf area index is reached.
`leaffall_dur`	Number of days until minimum leaf are index is reached.
`shp_optdoy`	Day of year when optimum value is reached (required when `method = "Coupmodel"`).
`shp_budburst`	Shape parameter for the growth phase (required when `method = "Coupmodel"`).
`shp_leaffall`	Shape parameter growth cessation (required when `method = "Coupmodel"`).
`lai_doy`	Integer vector of days of years.
`lai_frac`	Vector of values of fractional leaf area index corresponding to lai_doy (required when `method = "linear"`).

Value

A vector of daily lai values covering the years specified.

Examples

# Intraannual courses of leaf area index
lai_b90 <- make_seasLAI(method = "b90",
                       year = 2001,
                       maxlai = 5,
                       winlaifrac = 0,
                       budburst_doy = 121,
                       leaffall_doy = 280,
                       emerge_dur = 15,
                       leaffall_dur = 30)

lai_doy <- c(1,110,117,135,175,220,250,290,365)
lai_frac <- c(0.1,0.1,0.5,0.7,1.2,1.2,1.0,0.1,0.1)
lai_linear <- make_seasLAI(method = "linear",
                          year = 2001,
                          maxlai = 5,
                          lai_doy = lai_doy,
                          lai_frac = lai_frac)

lai_coupmodel <- make_seasLAI(method = "Coupmodel",
                             year = 2001,
                             maxlai = 5,
                             winlaifrac = 0.1,
                             budburst_doy = 110,
                             leaffall_doy = 280,
                             shp_optdoy = 180,
                             shp_budburst = 0.5,
                             shp_leaffall = 5)

plot(lai_b90, type = "n", xlab = "doy", ylab = "lai [m²/m²]", ylim = c(0,6))
lines(lai_b90, col ="green",lwd = 2,)
lines(lai_linear, col ="red",lwd = 2)
lines(lai_coupmodel, col ="blue",lwd = 2)

# incorparating between-year variability
years <- 2001:2003
lai <- make_seasLAI(method = "Coupmodel",
                   year = years,
                   maxlai = c(4,6,5),
                   budburst_doy = c(100,135,121),
                   leaffall_doy = 280,
                   shp_budburst = c(3,1,0.3),
                   shp_leaffall = 3,
                   shp_optdoy =c(210,180,240) )

dates <- seq.Date(as.Date("2001-01-01"), as.Date("2003-12-31"), by = "day")
plot(dates,lai, col = "green", ylab = "lai [m²/m²]",
     type ="l", xlab = "", lwd = 2)

LWFBrook90R

Simulate Evapotranspiration and Soil Moisture with the SVAT Model LWF-Brook90

v0.4.4

GPL-3

Authors

Paul Schmidt-Walter [aut, cre] (<https://orcid.org/0000-0003-2699-0893>), Volodymyr Trotsiuk [aut] (<https://orcid.org/0000-0002-8363-656X>), Klaus Hammel [aut], Martin Kennel [aut], Anthony Federer [aut], Robert Nuske [ctb] (<https://orcid.org/0000-0001-9773-2061>), Bavarian State Institute of Forestry (LWF) [cph, fnd], Northwest German Forest Research Institute (NW-FVA) [cph, fnd]

Initial release