LUE_YIELD_VPD: Light Use Efficiency Model to Estimate Crop Yield with Vapour...

In lue: Light Use Efficiency Model to Estimate Biomass and YIELD with and Without Vapour Pressure Deficit

Description

LUE_YIELD_VPD() to estimate crop yield firstly by calculating the Absorbed Photosynthetically Active Radiation (APAR) and secondly the actual values of light use efficiency by including vapour pressure deficit of the crops Shi et al.(2007) <doi:10.2134/agronj2006.0260>.

Usage

LUE_YIELD_VPD(fpar_raster,par,tmin,tmax,tdew,
tmin_min,tmin_max,vpd_max, vpd_min,LUE_optimal)

Arguments

fpar_raster	fraction of photosynthetically active radiation (fpar) per day raster with .tif format
par	clear sky surface photosynthetically active radiation (par) per day raster with .nc file format.
tmin	Minimum temperature at 2 metres since previous post-processing per day raster with .nc file format.
tmax	Maximum temperature at 2 metres since previous post-processing per day raster with .nc file format.
tdew	Dewpoint temperature at 2 metres since previous post-processing per day raster with .nc file format.
tmin_min	minimum value of tmin used for the threshold
tmin_max	maximum value of tmin used for the threshold
vpd_max	maximum value of vapour pressure deficit used for the threshold
vpd_min	minimum value of vapour pressure deficit used for the threshold
LUE_optimal	optical lue value with respect to crop type for example wheat crop LUE_optimal is 3.0 (Djumaniyazova et al., 2010)

Format

A Biomass raster

Value

Yield raster

References

Djumaniyazova Y, Sommer R, Ibragimov N, Ruzimov J, Lamers J & Vlek P (2010) Simulating water use and N response of winter wheat in the irrigated floodplains of Northwest Uzbekistan. Field Crops Research 116, 239-251.

Shi Z, Ruecker G R,Mueller M, Conrad C, Ibragimov N, Lamers J P A, Martius C, Strunz G, Dech S & Vlek P L G (2007) Modeling of Cotton Yields in the Amu Darya River Floodplains of Uzbekistan Integrating Multitemporal Remote Sensing and Minimum Field Data. Agronomy Journal 99, 1317-1326.

Examples

## Not run: 
## load the data
data(fpar)
data(par1)
data(tmin)
data(tmax)
data(tdew)
LUE_YIELD_VPD(fpar,par1,tmin,tmax,tdew,-2,12,1.5,4,3)

## End(Not run)
library(raster)
fparr <- raster(nc=2, nr=2)
values(fparr)<-runif(ncell(fparr),min =0.2,max= 0.8)
par11<- brick(nc=2, nr=2, nl=2)
values(par11)<-runif(ncell(par11),min =169076.9,max= 924474.6)
tminn <- brick(nc=2, nr=2, nl=2)
values(tminn)<-runif(ncell(tminn),min = 278,max= 281)
tmaxx <- brick(nc=2, nr=2, nl=2)
values(tmaxx)<-runif(ncell(tmaxx),min = 278,max= 281)
tdeww <- brick(nc=2, nr=2, nl=2)
values(tdeww)<-runif(ncell(tdeww),min = 278,max= 281)
LUE_YIELD_VPD(fparr,par11,tminn,tmaxx,tdeww,-2,12,1.5,4,3)

lue documentation built on May 2, 2019, 2:11 a.m.