medfate (version 0.8.2)

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_tissueRWC(psiSym, pi0, epsilon, 
                   psiApo, c, d, 
                   af, femb = 0)
moisture_tissueFMC(RWC, density, d0 = 1.54)
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.

density

Tissue density (g<U+00B7>cm-1).

d0

Matric density (g<U+00B7>cm-1).

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_segmentRWC: Segment relative water content [0-1].

Details

Details of the tissue moisture calculations are given in a vignette.

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")
# }