SoilRootCond: Calculate the soil to root conductivity for every defined...

In HannesDeDeurwaerder/SWIFT: SWIFT: Tracking stable water isotopic fluctuation along the length of a plant

Description

This function constructs a vector of soil to root conductivity for every defined soil layer [in s-1], while considering the soiltype

Usage

 SoilRootCond(B = NULL, kr = NULL, PSIs = NULL, Z = NULL, 
Soiltype = NULL)

Arguments

B	Description: Root length density at every discrete soil layer - Results from the function Bprep - [in m m-3]; Structure: A discrete vector of n elements, with n the number of soil layers
kr	Description: The root membrane permeability [s-1]; Structure: One value, representative of the studied plant
PSIs	Description: Soil water potential at the each specific soil layer [in m]; Structure: A vector of n element, where n corresponds to the number of soil layers; Note: The water potentials per soil layer is currently considered static in time
Z	Description: A vector of Soil depth [in m]; Structure: A discrete vector of n elements, where n corresponds to the number of soil layers
Soiltype	Description: Soil Tecture class studied (Sand; Loamy Sand; Sandy Loam; Silt Loam; Loam; Sandy Clay Loam; Silty Clay Loam; Clay Loam;Sandy Clay; Silty Clay; Clay); Structure: A Character string

Value

A vector of soil to root conductivity for every defined soil layer [in s-1]

Author(s)

Hannes De Deurwaerder, Marco D. Visser, Matteo Detto, Pascal Boeckx, Felicien Meunier and Hans Verbeeck

References

Soil texture characteristics are from: (a) Clapp and Hornberger (1978). Empirical equations for some soil hydraulic propert

Examples

		## The function is currently defined as
		function (B = NULL, kr = NULL, PSIs = NULL, Z = NULL, Soiltype = NULL){
    			if (Soiltype == "Sand") {
        			ksmax = 1.056/(100 * 60)
        			PSIsat = -0.121
        			b = 4.05
        			sigmasat = 0.395}

    			if (Soiltype == "Loamy Sand") {
        			ksmax = 0.938/(100 * 60)
        			PSIsat = -0.09
        			b = 4.38
        			sigmasat = 0.41}

    			if (Soiltype == "Sandy Loam") {
        			ksmax = 0.208/(100 * 60)
        			PSIsat = -0.218
        			b = 4.9
        			sigmasat = 0.435}

    			if (Soiltype == "Silt Loam") {
 			       ksmax = 0.0432/(100 * 60)
 			       PSIsat = -0.786
  			      	b = 5.3
   			     	sigmasat = 0.485}

    			if (Soiltype == "Loam") {
       			 	ksmax = 0.0417/(100 * 60)
       			 	PSIsat = -0.478
        			b = 5.39
        			sigmasat = 0.451}

    			if (Soiltype == "Sandy Clay Loam") {
        			ksmax = 0.0378/(100 * 60)
        			PSIsat = -0.299
        			b = 7.12
        			sigmasat = 0.42}

    			if (Soiltype == "Silty Clay Loam") {
        			ksmax = 0.0102/(100 * 60)
        			PSIsat = -0.356
        			b = 7.75
        			sigmasat = 0.477}

    			if (Soiltype == "Clay Loam") {
        			ksmax = 0.0147/(100 * 60)
        			PSIsat = -0.63
        			b = 8.52
        			sigmasat = 0.476}
    
			    if (Soiltype == "Sandy Clay") {
        			ksmax = 0.013/(100 * 60)
        			PSIsat = -0.153
        			b = 10.4
        			sigmasat = 0.426}

    	    if (Soiltype == "Silty Clay") {
        			ksmax = 0.0062/(100 * 60)
        			PSIsat = -0.49
        			b = 10.4
        			sigmasat = 0.492}

			    if (Soiltype == "Clay") {
        			ksmax = 0.0077/(100 * 60)
        			PSIsat = -0.405
        			b = 11.4
        			sigmasat = 0.482}

    			k = ks <- rep(NA, length(Z))
            for (h in 1:length(Z)){
                ks[h] <-  ksmax * (PSIsat/PSIs[h])^(2+3/b)    
                k[h]<- kr * ks[h]*sqrt(pi*B[h]) / (0.53*kr + ks[h]*sqrt(pi*B[h]) )
          
              }
    			return(k)
  			}

HannesDeDeurwaerder/SWIFT documentation built on March 22, 2021, 4:49 p.m.