TwopSeriesModel: Implementation of a two pool model with series structure

In SoilR: Models of Soil Organic Matter Decomposition

Implementation of a two pool model with series structure

Description

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

Usage

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

Arguments

t	A vector containing the points in time where the solution is sought.
ks	A vector of length 2 with the values of the decomposition rate for pools 1 and 2.
a21	A scalar with the value of the transfer rate from pool 1 to pool 2.
C0	A vector of length 2 containing the initial amount of carbon for the 2 pools.
In	A scalar or a data.frame object specifying the amount of litter inputs by time.
xi	A scalar or a data.frame 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

Value

A Model Object that can be further queried

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.

See Also

There are other predefinedModels and also more general functions like Model.

Examples

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)
a21=0.5
C0=c(C10=100,C20=150)
In = 30
#
Temp=rnorm(t,15,1)
TempEffect=data.frame(t,fT.Daycent1(Temp))
#
Ex1=TwopSeriesModel(t,ks,a21,C0,In,xi=TempEffect)
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) 
legend("bottomright",c("Total C","C in pool 1", "C in pool 2"),
lty=c(1,1,1),col=c(1,2,4),lwd=c(2,1,1),bty="n")

SoilR documentation built on Oct. 13, 2023, 5:06 p.m.