calculate_WUE_o: Calculation of WUE_o

In oscarperezpriego/ETpartitioning: Partitioning of eddy covariance ET into flux components

Description

Calculation of WUE_o (see Perez-Priego et al., 2018).

Usage

calculate_WUE_o(data, ColPhotos, ColVPD, ColTair, C, Z)

Arguments

data	Data.frame or matrix containing all required variables.
ColPhotos	column name of numeric vector containing time series of photosynthesis data (umol CO2 m-2 s-1)
ColVPD	column name of numeric vector containing time series of vapor pressure deficit (kPa).
ColTair	column name of numeric vector containing time series of air temperature (deg C).
C	Empirical coeficient for C3 species.
Z	Z- numeric value defining elevation (km).

Details

the following metrics are calculated:

WUE_o:

WUE_o <- (390*(1-chi_o)*96)/(1.6*VPD_g)*0.001

VPD_g is calculated based on the mean value of the growing period. While chi_o is calculated using calculate_chi_o function The growing period is estimated as those periods over the 85 quantile of Ph.

Value

a numeric value:

WUE_o

long-term effective "Water use efficiency (umolCO2 mmol-1)

Note

Photos is calculated based on night-time NEE partitioning approach (Reichstein et al., 2005). chi_o is calculated following Perez-Priego et al., 2018.

References

Perez-Priego, O., G. Katul, M. Reichstein et al. Partitioning eddy covariance water flux components using physiological and micrometeorological approaches, Journal of Geophysical Research: Biogeosciences. In press

Reichstein, M., et al. (2005), On the separation of net ecosystem exchange into assimilation and ecosystem respiration: review and improved algorithm, Global Change Biology, 11(9), 1424-1439.

Examples

calculate_WUE_o(data= EddySample
,ColPhotos = "GPP_NT_VUT_MEAN"
,ColVPD = "VPD_F"
,ColTair = "TA_F"
,C = 1.189 ##<< Empirical coeficient for C3 species (see Wang et al., 2017; Plant Nature).
,Z=0.27)

oscarperezpriego/ETpartitioning documentation built on June 4, 2019, 12:13 a.m.