SoilR (version 1.0-0)

TwopParallelModel: Implementation of a two pool model with parallel structure

Description

This function creates a model for two independent (parallel) pools. It is a wrapper for the more general function ParallelModel that can handle an arbitrary number of pools.

Usage

TwopParallelModel(t, ks, C0, In, gam, xi = 1, solver = deSolve.lsoda.wrapper)

Arguments

t

A vector containing the points in time where the solution is sought.

ks

A vector of length 2 containing the decomposition rates for the 2 pools.

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.

gam

A scalar representing the partitioning coefficient, i.e. the proportion from the total amount of inputs that goes to pool 1.

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 ode or any other user provided function with the same interface.

Value

• A Model Object that can be further queried

See Also

ThreepParallelModel

Examples

t_start=0 
t_end=10 
tn=50
timestep=(t_end-t_start)/tn 
t=seq(t_start,t_end,timestep) 

Ex=TwopParallelModel(t,ks=c(k1=0.5,k2=0.2),C0=c(c10=100, c20=150),In=10,gam=0.7,xi=0.5)
Ct=getC(Ex)

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

Rt=getReleaseFlux(Ex)
plot(t,rowSums(Rt),type="l",ylab="Carbon released (arbitrary units)",xlab="Time",lwd=2,ylim=c(0,sum(Rt[1,]))) 
lines(t,Rt[,1],col=2)
lines(t,Rt[,2],col=4) 
legend("topleft",c("Total C release","C release from pool 1", "C release from pool 2"),lty=c(1,1,1),col=c(1,2,4),lwd=c(2,1,1),bty="n")