UvasCreek: Strontium injection experiment in Uvas Creek, a small stream...
In simecolModels: Model collection for the simecol package

Description Usage Format Author(s) References See Also Examples

Model describing a Strontium injection experiment in Uvas Creek, a small stream (cross section 0.5 m2, length 619 m) in North Carolina.

(Bencala and Walters 1983).

Originally implemented in the OTIS modelling framework (Runkel, 1989) (application 2)

Strontium was injected at a constant rate in the upstream part of this creek for 3 hours, to reach a maximal concentration of 1.7 mg L-1, whereas the background concentration was 0.13 mg L-1.

The passing of the concentration pulses was assessed at various river positions downstream (38, 105, 281, 433 and 619 m).

The model describes Strontium in a free-flowing zone and a stagnant zone and in the streambed, where strontium is absorbed.

The stream is subdivided into five segments with different cross-sectional areas, storage zone areas and exchange parameters.

1	UvasCreek()

An S4 object according to the odeModel specification.

The object contains the following slots:

main Model specifications.
parms Vector with the named parameters of the model - see code
times Simulation time and integration interval.
init Vector with start values for the state variables.
inputs External forcings, the tracer concentration that is injected at the upstream boundary

The model is solved using integration routine ode.1D from package deSolve.

Karline Soetaert

Bencala, K.E., and Walters, R.A., 1983, Simulation of solute transport in a mountain pool-and-riffle stream-A transient storage model: Water Resources Research, v. 19, no. 3, p. 718-724.

Runkel, R.L., 1998. One-dimensional transport with inflow and storage (OTIS): a solute transport model for streams and rivers. US geological Survey. Water-Resources Investigations Report 98-4018. Denver, Colorado.

R-package simecol for a description of the simObj class

  
#----------------------#
# Create Instance      #
#----------------------#

# Note: lower case letter of the instance and capital letter of the constructor
uvasCreek <- UvasCreek()

# show model code, parameter settings,...
print(uvasCreek)

#----------------------#
# RUNNING the model:   #
#----------------------#

# run simulation
outp <- out(sim(uvasCreek, nspec=3))

#------------------------#
# PLOTTING model output: #
#------------------------#
Data38 <- matrix (nc=2, byrow=TRUE, data = c(8.,0.143,9.,1.528,
10.,1.59,11.,1.599,12.,0.229,13.,0.173,14.,0.173,15.,0.140,
16.17,0.159,16.68,0.156,17.68,0.165,18.68,0.151,
19.68,0.155,20.68,0.158,21.68,0.134))

Data281 <- matrix (nc=2, byrow=TRUE, data = c(7.8,0.131,9.,0.134,
10.,0.135,11.,0.696,12.,0.946,13.,1.021,14.,0.486,15.,0.288,
16.,0.205,17.,0.207,18.37,0.185,19.37,0.178,20.37,0.174,21.37,
0.168,22.37,0.165,23.37,0.159))

Data433 <- matrix (nc=2, byrow=TRUE, data = c(9.,0.133,10,0.152,
11,0.131,12,0.359,13,0.557,14,0.684,15,0.524,16,0.349,
17,0.240,18,0.218,19.5,0.175,20.5,0.173,21.5,0.168,22.5,0.154))


# Plot strontium; first get the data
Dist  <- inputs(uvasCreek)$boxes$x
times <- outp$times/3600

par(mfrow=c(2,2))
par(oma=c(0,0,3,0))   # set margin size (oma)
image(x=times, y=Dist, z=outp$C,
      col= terrain.colors(100), xlab="time, hour",
      ylab= "Distance, m", main="Strontium")
mtext(outer=TRUE, side=3, "Uvas Creek", cex=1.5)

plot(times,outp$C[,38],  xlab="time, hour", ylab="mg/L",
  main="38m", type="l")
points(Data38, pch = 18)

plot(times,outp$C[,281], xlab="time, hour", ylab="mg/L",
  main="281m", type="l")
points(Data281, pch = 18)

plot(times,outp$C[,433], xlab="time, hour", ylab="mg/L",
  main="433m", type="l")
points(Data433, pch = 18)