f.canopy.interception: Function to describe the light levels inside the canopy

In TESTgroup-BNL/LeafGasExchange: A package containing functions for fitting photosynthetic response curves, simulat leaf and canopy photosynthesis

Function to describe the light levels inside the canopy

Description

Function to describe the light levels inside the canopy

Usage

f.canopy.interception(
  meteo_hourly,
  lat,
  DOY,
  nlayers,
  dLAI,
  LAI,
  Rho = 0.11,
  Tau = 0.06,
  Rho_soil = 0.1,
  Rho_NIR = 0.46,
  Tau_NIR = 0.33,
  Rho_soil_NIR = 0.33,
  chil = 0.32,
  clumpfac = 0.85,
  model = "Norman"
)

Arguments

meteo_hourly	Hourly weather data frame with at least the column time (time in numeric, for example 0 to 23),Tair (air temperature in degree C), RH (humidity in pc from 0 to 100), cs the CO2 concentration and PFD the total PFD in micro mol m-2 s-1.
lat	Latitude of the canopy to model.
DOY	Day of Year .
nlayers	Number of layers inside the canopy (max = 50).
dLAI	LAI of each one of the n layers of vegetation in the canopy.
LAI	Cumulated LAI in the midle of each layer.
Rho	Leaf reflectance in the visible wavelengths.
Tau	Leaf transmittance in the visible wavelengths.
Rho_soil	Soil reflectance in the visible wavelengths.
Rho_NIR	Leaf reflectance in the NIR wavelengths.
Tau_NIR	Leaf transmittance in the NIR wavelengths.
Rho_soil_NIR	Soil reflectance in the NIR wavelengths.
chil	Index of departure of the leaf angles from a spherical distribution. -0.4 < chil < 0.6.
clumpfac	Clumping factor, index of non random spatial distribution of leaves. = 1 for randomly spaced leaves, <1 for clumed leaves (Chen et al. 2012).
model	Model for the radiation interception model, default is Norman (only Norman implemented so far).

Examples

##Simulation of the vegetation
LAItot = 6
nlayers=20
dLAI=rep(6/nlayers,nlayers)
LAI=cumsum(dLAI)-dLAI/2 # LAI in the midle of each layer
##Simulation of the weather
meteo_hourly=data.frame(time=0:23,RH=80,Tair=25,cs=400,PFD=dnorm(x = seq(0,23,1),mean = 12,sd = 2.5)/0.16*2000,Tleaf=25)
##Simulation of position and moment of the simulation
lat=9.2801048
DOY = 60
##Representation of the light interception inside the canopy
canopy=f.canopy.interception(meteo_hourly=meteo_hourly,lat = lat,DOY = DOY,nlayers = nlayers,dLAI = dLAI,LAI=LAI)

TESTgroup-BNL/LeafGasExchange documentation built on May 17, 2024, 8:11 p.m.