ThreepSeriesModel: Implementation of a three pool model with series structure

Description

This function creates a model for three pools connected in series. It is a wrapper for the more general function GeneralModel.

Usage

ThreepSeriesModel(
  t,
  ks,
  a21,
  a32,
  C0,
  In,
  xi = 1,
  solver = deSolve.lsoda.wrapper,
  pass = FALSE
)

Value

A Model Object that can be further queried

Arguments

t: A vector containing the points in time where the solution is sought.
ks: A vector of length 3 containing the values of the decomposition rates for pools 1, 2, and 3.
a21: A scalar with the value of the transfer rate from pool 1 to pool 2.
a32: A scalar with the value of the transfer rate from pool 2 to pool 3.
C0: A vector of length 3 containing the initial amount of carbon for the 3 pools.
In: A scalar or data.frame object specifying the amount of litter inputs by time.
xi: A scalar or data.frame object specifying the external (environmental and/or edaphic) effects on decomposition rates.
solver: A function that solves the system of ODEs. This can be euler or deSolve.lsoda.wrapper or any other user provided function with the same interface.
pass: if TRUE Forces the constructor to create the model even if it is invalid

References

Sierra, C.A., M. Mueller, S.E. Trumbore. 2012. Models of soil organic matter decomposition: the SoilR package version 1.0. Geoscientific Model Development 5, 1045-1060.

Examples

Run this code

t_start=0 
t_end=10 
tn=50
timestep=(t_end-t_start)/tn 
t=seq(t_start,t_end,timestep) 
ks=c(k1=0.8,k2=0.4,k3=0.2)
C0=c(C10=100,C20=150, C30=50)
In = 50

Ex1=ThreepSeriesModel(t=t,ks=ks,a21=0.5,a32=0.2,C0=C0,In=In,xi=fT.Q10(15))
Ct=getC(Ex1)
Rt=getReleaseFlux(Ex1)

plot(t,rowSums(Ct),type="l",ylab="Carbon stocks (arbitrary units)",
xlab="Time (arbitrary units)",lwd=2,ylim=c(0,sum(Ct[1,]))) 
lines(t,Ct[,1],col=2)
lines(t,Ct[,2],col=4)
lines(t,Ct[,3],col=3)
legend("topright",c("Total C","C in pool 1", "C in pool 2","C in pool 3"),
lty=c(1,1,1,1),col=c(1,2,4,3),lwd=c(2,1,1,1),bty="n")