Functions used to scale from tissue conductivity to conductance of different elements of the continuum.
hydraulics_maximumSoilPlantConductance(krhizomax, krootmax,
kstemmax, kleafmax)
hydraulics_soilPlantResistances(psiSoil, psiRhizo,
psiStem, PLCstem, psiLeaf,
krhizomax, n, alpha,
krootmax, rootc, rootd,
kstemmax, stemc, stemd,
kleafmax, leafc, leafd)
hydraulics_averageRhizosphereResistancePercent(krhizomax, n, alpha,
krootmax, rootc, rootd,
kstemmax, stemc, stemd,
kleafmax, leafc, leafd, psiStep = -0.01)
hydraulics_findRhizosphereMaximumConductance(averageResistancePercent, n, alpha,
krootmax, rootc, rootd,
kstemmax, stemc, stemd,
kleafmax, leafc, leafd)
hydraulics_maximumRootHydraulicConductance(xylemConductivity, Al2As,
v, widths, depthWidthRatio = 1.0)
hydraulics_maximumStemHydraulicConductance(xylemConductivity, refheight, Al2As, height,
angiosperm = TRUE, taper = FALSE)
hydraulics_referenceConductivityHeightFactor(refheight, height)
hydraulics_terminalConduitRadius(height)
hydraulics_taperFactorSavage(height)
hydraulics_stemWaterCapacity(Al2As, height, wd)
hydraulics_leafWaterCapacity(SLA, ld)Soil water potential (in MPa). A scalar or a vector depending on the function.
Water potential (in MPa) in the rhizosphere (root surface).
Water potential (in MPa) in the stem.
Water potential (in MPa) in the leaf.
Percent loss of conductance (in %) in the stem.
Proportion of fine roots within each soil layer.
Maximum rhizosphere hydraulic conductance (defined as flow per leaf surface unit and per pressure drop).
Maximum leaf hydraulic conductance (defined as flow per leaf surface unit and per pressure drop).
Maximum stem xylem hydraulic conductance (defined as flow per leaf surface unit and per pressure drop).
Maximum root xylem hydraulic conductance (defined as flow per leaf surface unit and per pressure drop).
Water potential precision (in MPa).
Parameters of the Weibull function for roots (root xylem vulnerability curve).
Parameters of the Weibull function for stems (stem xylem vulnerability curve).
Parameters of the Weibull function for leaves (leaf vulnerability curve).
Parameters of the Van Genuchten function (rhizosphere vulnerability curve).
Average (across water potential values) resistance percent of the rhizosphere, with respect to total resistance (rhizosphere + root xylem + stem xylem).
Xylem conductivity as flow per length of conduit and pressure drop (in kg<U+00B7>m-1<U+00B7>s-1<U+00B7>MPa-1).
Leaf area to sapwood area (in m2<U+00B7>m-2).
Plant height (in cm).
Reference plant height (in cm).
A boolean flag to indicate an angiosperm species.
A boolean flag to indicate correction by taper of xylem conduits (Christoffersen et al. 2017).
Soil layer depths (in mm).
Ratio between radius of the soil layer with the largest radius and maximum rooting depth.
Specific leaf area (mm2<U+00B7>mg-1).
Wood density (g<U+00B7>cm-3).
Leaf tissue density (g<U+00B7>cm-3).
Values returned for each function are:
hydraulics_maximumSoilPlantConductance: The maximum soil-plant conductance, in the same units as the input segment conductances.
hydraulics_averageRhizosphereResistancePercent: The average percentage of resistance due to the rhizosphere, calculated across water potential values.
hydraulics_findRhizosphereMaximumConductance: The maximum rhizosphere conductance value given an average rhizosphere resistance and the vulnerability curves of rhizosphere, root and stem elements.
hydraulics_taperFactorSavage: Taper factor according to Savage et al. (2010).
Details of the hydraulic model are given in a vignette.
Christoffersen, B. O., M. Gloor, S. Fauset, N. M. Fyllas, D. R. Galbraith, T. R. Baker, L. Rowland, R. A. Fisher, O. J. Binks, S. A. Sevanto, C. Xu, S. Jansen, B. Choat, M. Mencuccini, N. G. McDowell, and P. Meir. 2016. Linking hydraulic traits to tropical forest function in a size-structured and trait-driven model (TFS v.1-Hydro). Geoscientific Model Development Discussions 9: 4227<U+2013>4255.
Savage, V. M., L. P. Bentley, B. J. Enquist, J. S. Sperry, D. D. Smith, P. B. Reich, and E. I. von Allmen. 2010. Hydraulic trade-offs and space filling enable better predictions of vascular structure and function in plants. Proceedings of the National Academy of Sciences of the United States of America 107:22722<U+2013>7.
Olson, M.E., Anfodillo, T., Rosell, J.A., Petit, G., Crivellaro, A., Isnard, S., Le<U+00F3>n-G<U+00F3>mez, C., Alvarado-C<U+00E1>rdenas, L.O., & Castorena, M. 2014. Universal hydraulics of the flowering plants: Vessel diameter scales with stem length across angiosperm lineages, habits and climates. Ecology Letters 17: 988<U+2013>997.
# NOT RUN {
kstemmax = 4 # in mmol<U+00B7>m-2<U+00B7>s-1<U+00B7>MPa-1
stemc = 3
stemd = -4 # in MPa
# }
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