soil.texture: Soil texture triangle plot

In plotrix: Various Plotting Functions

Soil texture triangle plot

Description

Display a USDA soil texture triangle with optional grid, labels and soil texture points.

Usage

soil.texture(soiltexture=NULL, main="", at=seq(0.1, 0.9, by=0.1),
             axis.labels=c("percent sand", "percent silt",
                           "percent clay"),
             tick.labels=list(l=seq(10, 90, by=10), r=seq(10, 90, by=10),
                              b=seq(10, 90, by=10)),
             show.names=TRUE, show.lines=TRUE, col.names="gray",
             bg.names=par("bg"), show.grid=FALSE, col.axis="black",
             col.lines="gray", col.grid="gray", lty.grid=3,
             show.legend=FALSE, label.points=FALSE, point.labels=NULL,
             col.symbols="black", pch=par("pch"), ...)

Arguments

soiltexture	Matrix of soil textures where each row is a soil sample and three columns contain the proportions of the components sand, silt and clay in the range 0 to 1 or percentages in the range 0 to 100.
main	The title of the soil texture plot. Defaults to nothing.
at	Positions on the three axes where ticks will be drawn.
axis.labels	Labels for the axes.
tick.labels	The tick labels for the three axes.
show.names	Logical - whether to show the names of different soil types within the soil triangle.
show.lines	Logical - whether to show the boundaries of the different soil types within the soil triangle.
col.names	Color of the soil names. Defaults to gray.
bg.names	Color to use when drawing a blank patch for the names of soil types.
show.grid	Logical - whether to show grid lines at each 10 level of each soil component.
col.axis	Color of the triangular axes, ticks and labels.
col.lines	Color of the boundary lines. Defaults to gray.
col.grid	Color of the grid lines. Defaults to gray.
lty.grid	Type of line for the grid. Defaults to dashed.
show.legend	Logical - whether to display a legend.
label.points	Logical - whether to call thigmophobe.labels to label the points.
point.labels	Optional labels for the points or legend.
col.symbols	Color of the symbols representing each value.
pch	Symbols to use in plotting values.
...	Additional arguments passed to triax.points and then ‘⁠points⁠’.

Details

‘⁠soil.texture⁠’ displays a triangular plot area on which soil textures defined as proportions of sand, silt and clay can be plotted. Optional grid, vertex labels, soil type divisions and names may also be displayed. If a matrix of soil textures is present, these will be plotted.

Value

If ‘⁠soiltexture⁠’ was included, a list of the ‘⁠x,y⁠’ positions of the soil types plotted. If not, nil.

Note

This is now a special case of ‘⁠triax.plot⁠’.

Author(s)

Sander Oom, Jim Lemon, and Michael Toews

References

U.S. Department of Agriculture, Natural Resources Conservation Service, 2007. National Soil Survey Handbook, title 430-VI.// formerly ‘⁠https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/survey/class/taxonomy/?cid=nrcs142p2_053577⁠’

U.S. Department of Agriculture, Natural Resources Conservation Service, 2007. Soil Texture Calculator// formerly ‘⁠https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/survey/class/taxonomy/?cid=nrcs142p2_053577⁠’

See Also

get.soil.texture, triax.plot

Examples

 data(soils)
 soil.texture(main="NO DATA")
 soil.texture(soils, main="DEFAULT", pch=2)
 soil.texture(soils, main="LINES AND NAMES", show.lines=TRUE,
  show.names=TRUE, pch=3)
 soiltex.return<-soil.texture(soils[1:6,], main="GRID AND LEGEND",
  show.grid=TRUE, pch=4, col.symbols=1:6, show.legend=TRUE)
 par(soiltex.return$oldpar)

plotrix documentation built on Nov. 10, 2023, 5:07 p.m.