PAIfromhabitat: Derives leaf area index, leaf geometry and canopy height from...

In ilyamaclean/microctools: Various worker functions for microclimc package

Derives leaf area index, leaf geometry and canopy height from habitat

Description

PAIfromhabitat generates an hourly dataset for an entire year of leaf area index values, the ratio of vertical to horizontal projections of leaf foliage and canopy height from habitat.

Usage

PAIfromhabitat(
  habitat,
  lat,
  long,
  year,
  meantemp = NA,
  cvtemp = NA,
  rainfall = NA,
  cvrain = NA,
  wetmonth = NA
)

Arguments

habitat	a character string or numeric value indicating the habitat type. See habitats()
lat	a single numeric value representing the mean latitude of the location for which the solar index is required (decimal degrees, -ve south of the equator).
long	a single numeric value representing the mean longitude of the location for which the solar index is required (decimal degrees, -ve west of Greenwich meridian).
year	the year for which data are required.
meantemp	an optional numeric value of mean annual temperature (ºC) at reference height.
cvtemp	an optional numeric value of the coefficient of variation in temperature (K per 0.25 days) at reference height.
rainfall	an optional numeric value mean annual rainfall (mm per year)
cvrain	an optional numeric value of the coefficient of variation in raifall (mm per 0.25 days) at reference height.
wetmonth	an optional numeric value indicating which month is wettest (1-12).

Details

If no values of meantemp, cvtemp, rainfall, cvrain or wetmonth are provided, values are obtained from globalclimate(). Variable lai is derived by fitting a Gaussian curve parameters of which are climate and location-dependent. Functional fits were calibrated using MODIS data (see https://modis.gsfc.nasa.gov/data/).

Value

a list with the following items:

lai hourly leaf area index values,

x the ratio of vertical to horizontal projections of leaf foliage

height the heigbht of the canopy in metres

obs_time an object of class POSIXlt of dates and times coressponding to each value of lai

Examples

pxh <- PAIfromhabitat("Deciduous broadleaf forest", 50, -5.2, 2015)
pxh$height
pxh$x
plot(pxh$lai ~ as.POSIXct(pxh$obs_time), type = "l", xlab = "Month",
     ylab = "LAI", ylim = c(0, 6))

ilyamaclean/microctools documentation built on Jan. 25, 2023, 5:29 a.m.