Func_Canopy_Radiation_Transfer: Func_Canopy_Radiation_Transfer

In TEST-BNL/R-Canopy_Photosynthesis: Canopy photosynthesis testbed

Description

Function for revised DF1997 model to partition canopy LAI into sunlit/shade leaves LAI and partition canopy Vcmax into sunlit/shade leaves Vcmax clumping index was added to original DF1997 model, following the reference from Ryu et al. 2011

Usage

Func_Canopy_Radiation_Transfer(FLAG, SZA, LAI, Ib0, Id0, Vcmax0_25, CI)

Arguments

FLAG	Model version controller; 0–Lloyd et al. 2010 Model for Vcmax-LAI relationship; 1–Mercado et al. 2006 Model for Vcmax-LAI relationship in the tropics
SZA	solar zenith angle, in degrees
LAI	Canopy leaf area index
Ib0	direct beam at canopy top
Id0	diffuse irradiance at canopy top
Vcmax0_25	Vcmax at reference 25 degrees C for top-of-canopy leaves
CI	Clumping inedx; 0.63 for tropical evergreen forests (Chen et al, 2005)

Details

Goal: Use revised DF1997 model to partition canopy LAI into sunlit/shade leaves LAI and partition canopy Vcmax into sunlit/shade leaves Vcmax clumping index was added to original DF1997 model, following the reference from Ryu et al. 2011

Value

List containing: PAR0 - ; Ib0 - ; Id0 - ; Lsun - Sunlit LAI; Lshade - Shade LAI; Ic - Canopy total absorbed irradiance; Isun - Sunlit leaf absorbed irradiance; Ishade - Shade leaf absorbed irradiance; Vc - Canopy total Vcmax; Vcsun - Sunlit leaf Vcmax; Vcshade - Shade leaf Vcmax

Author(s)

Jin Wu

Shawn Serbin

References

dePury and Farquhar, 1997; Ryu et al., 2011

Examples

FLAG <- 1
SZA <- 30
LAI <- 6
Press <- 10^5
PAR0 <- 1320 # top canop irradiance, in umol/m2/s
Vcmax0_25 <- 40 # Bonan et al., 2012 for the tropcis
Clumping <- 0.63 # Clumping index, from Chen etal., 2005 for tropical evergreen forests

LQ <- Func_Light_Partitioning(SZA=SZA,P=Press,PAR=PAR0)
Ib0 <- LQ$Model_DV
Id0 <- LQ$Model_dV

output <- Func_Canopy_Radiation_Transfer(FLAG=FLAG, SZA=SZA, LAI=LAI, Ib0=Ib0, Id0=Id0, Vcmax0_25=Vcmax0_25, CI=Clumping)

TEST-BNL/R-Canopy_Photosynthesis documentation built on Nov. 13, 2020, 6:37 p.m.