medfate (version 2.3.7)

tissuemoisture: Tissue moisture functions

Description

Set of functions used to calculate tissue moisture from water potential and viceversa.

Usage

moisture_symplasticRWC(psiSym, pi0, epsilon)
moisture_symplasticPsi(RWC, pi0, epsilon)
moisture_apoplasticRWC(psiApo, c, d)
moisture_apoplasticPsi(RWC, c, d)
moisture_turgorLossPoint(pi0, epsilon) 
moisture_tissueRWC(psiSym, pi0, epsilon, 
                   psiApo, c, d, 
                   af, femb = 0)
moisture_cohortFMC(spwb, SpParams)
moisture_cohortFMCDay(spwb_day, x, SpParams)
moisture_pressureVolumeCurvePlot(x, segment="leaf", 
                    fraction = "all",
                    psiVec =  seq(-0.1, -8.0, by =-0.01),
                    speciesNames = FALSE)

Arguments

psiSym, psiApo

Symplastic or apoplastic water potential (MPa).

RWC

Relative water content [0-1].

pi0

Full turgor osmotic potential (MPa).

epsilon

Bulk modulus of elasticity (MPa).

c,d

Parameters of the xylem vulnerability curve.

af

Apoplastic fraction (proportion) in the segment (e.g. leaf or stem).

femb

Fraction of embolized conduits.

x

An object of class spwbInput.

segment

Segment whose relative water content curve to plot, either "stem" or "leaf".

fraction

Tissue fraction, either "symplastic", "apoplastic" or "all".

psiVec

Vector of water potential values to evaluate for the pressure-volume curve.

speciesNames

A flag to indicate the use of species names instead of cohort names in plots.

spwb

Object returned by function spwb or growth.

spwb_day

Object returned by function spwb_day or growth_day.

SpParams

A data frame with species parameters (see SpParamsMED and SpParamsMED).

Value

Values returned for each function are:

• moisture_symplasticRWC: Relative water content [0-1] of the symplastic fraction.

• moisture_apoplasticRWC: Relative water content [0-1] of the apoplastic fraction.

• moisture_symplasticWaterPotential: Water potential (in MPa) of the symplastic fraction.

• moisture_apoplasticWaterPotential: Water potential (in MPa) of the apoplastic fraction.

• moisture_turgorLossPoint: Water potential (in MPa) corresponding to turgor loss point.

• moisture_segmentRWC: Segment relative water content [0-1].

• moisture_cohortFMC: A matrix with daily moisture content per dry weight (in percent) of each cohort.

• moisture_cohortFMCDay: A vector with moisture content per dry weight (in percent) of each cohort.

Details

Details of the tissue moisture calculations are given in a vignette. Function moisture_cohortFMC() calculates the fuel moisture content of leaves of each cohort, from the results of soil water balance.

References

Bartlett, M.K., Scoffoni, C., Sack, L. 2012. The determinants of leaf turgor loss point and prediction of drought tolerance of species and biomes: a global meta-analysis. Ecology Letters 15: 393<U+2013>405.

H<U+00F6>ltt<U+00E4>, T., Cochard, H., Nikinmaa, E., Mencuccini, M. 2009. Capacitive effect of cavitation in xylem conduits: Results from a dynamic model. Plant, Cell and Environment 32: 10<U+2013>21.

Martin-StPaul, N., Delzon, S., Cochard, H. 2017. Plant resistance to drought depends on timely stomatal closure. Ecology Letters 20: 1437<U+2013>1447.

See Also

hydraulics_psi2K, hydraulics_supplyFunctionPlot, spwb, soil

Examples

# NOT RUN {
psi = seq(-10,0, by=0.1)
rwc_s = rep(NA, length(psi))
for(i in 1:length(psi)) rwc_s[i] = moisture_symplasticRWC(psi[i],-3,12)
plot(psi, rwc_s, type="l", xlab="Water potential (MPa)", ylab = "Symplasmic RWC")
# }