horizonColorIndices: Horizon Color Indices

In aqp: Algorithms for Quantitative Pedology

Horizon Color Indices

Description

Calculate basic horizon-level color indices for a SoilProfileCollection. Basic indices do not require aggregation over the whole profile or comparison to a "reference" (e.g. parent material) color. Includes Hurst (1977) Redness Index, Barron-Torrent Redness Index (1986) and Buntley-Westin Index (1965). This is a wrapper method around several horizon-level indices. See the individual functions for more details.

Usage

horizonColorIndices(p, hue = "m_hue", value = "m_value", chroma = "m_chroma")

Arguments

p	A SoilProfileCollection
hue	Column name containing moist hue; default: "m_hue"
value	Column name containing moist value; default: "m_value"
chroma	Column name containing moist chroma; default: "m_chroma"

Value

A data.frame containing unique pedon and horizon IDs and horizon-level color indices.

Author(s)

Andrew G. Brown

See Also

hurst.redness barron.torrent.redness.LAB buntley.westin.index

Examples

# keep examples from using more than 2 cores
data.table::setDTthreads(Sys.getenv("OMP_THREAD_LIMIT", unset = 2))

data(sp1)

# promote sp1 data to SoilProfileCollection
depths(sp1) <- id ~ top + bottom

# move site data
site(sp1) <- ~ group

# use Munsell color notation as horizon name
sp1$m <- sprintf("%s %s/%s", sp1$hue, sp1$value, sp1$chroma)

# compute indices
# merged into `sp1` with left-join on hzidname(sp1)
horizons(sp1) <- horizonColorIndices(sp1, hue="hue", value="value", chroma="chroma")

# visualize
par(mar = c(0, 1, 3, 1))
plotSPC(sp1, color='hurst_redness', name = 'm')
plotSPC(sp1, color='barron_torrent_redness', name = 'm')
plotSPC(sp1, color='buntley_westin', name = 'm')

aqp documentation built on Oct. 19, 2024, 5:06 p.m.