Keys a PedonRecord through the Chinese Soil Taxonomy
(Cooperative Research Group on Chinese Soil Taxonomy, 2001, the English
edition published by Science Press). Experimental: this release
keys the 14 orders (key 5.1: Histosols, Anthrosols, Spodosols, Andosols,
Ferralosols, Vertosols, Aridosols, Halosols, Gleyosols, Isohumosols,
Ferrosols, Argosols, Cambosols and Primosols), their 39 suborders and
their 138 groups (key 5.2), with soilKey's residuals [E2] [Other
Ferralosols], [A1.4] [Other Permagelic Histosols] and
[A2.5] [Other Orthic Histosols] where the book prints none (the
name stops there, with a note). Since v0.9.375 it keys the subgroups of
orders A to G (176, with [A1.3.x] Lithic Hemi-Permagelic Histosols,
listed in Appendix 1 only, at its Appendix position); their criteria are
written as presets (inst/rules/cst2001/presets.yaml), expanded
when the rules are loaded. The groups of orders H to N stop at the group,
with a note, until their subgroups follow in a later release.
Usage
classify_cst2001(
pedon,
rules = NULL,
on_missing = c("warn", "silent", "error"),
gapfill = FALSE
)Arguments
- pedon
A
PedonRecord.- rules
Optional pre-loaded rule set (
load_rules("cst2001")).- on_missing
One of
"warn"(default),"silent","error".- gapfill
Opt-in within-pedon gap-fill, as in
classify_usda.
Value
A ClassificationResult with system_id
"cst2001", the subgroup (or the deepest class assigned) in
name, the order in rsg_or_order, the classes
of each level in levels (with name_pt and
book_provisional), the key trace with the horizon panel,
provisional_because, and, when a class was assigned on a
provisional reading, in candidates the class the key would
reach without it (kind "alternative").
Details
The key is read in the book's order, the first class whose criteria pass
assigned, as the book prescribes (each class lacks the properties of the
classes before it). The criteria read the 33 diagnostic horizons and the
25 diagnostic characteristics of chapter 3 on the recorded data (see
identify_horizons with "cst2001"), with their
weaker evidence grades where the book gives them, the soil moisture and
temperature regimes (recorded on the site, or from the aridity index, the
site's records of paddy, groundwater and permafrost, and the air
temperature), and the few criteria the key defines where it uses them.
Every test is three-valued: a measurement not recorded leaves it
undecided, a field observation not recorded is absent. A class tested
before the assigned one that could not be decided makes the name
provisional (provisional_because); a class assigned on a reading
the book leaves open (gley colours without a ferrous-iron test, cracks
observed for their duration) carries a warning; a class the book itself
marks provisional is noted as such (levels$book_provisional).
Names are the English of the book, in the plural of the key
("Permagelic Histosols"), with soilKey's Portuguese gloss in
levels$name_pt. The approximate equivalents of the order in US Soil
Taxonomy (1999) and the WRB (1998), Tables 4.2 and 4.3, are added as a
note (qualifiers$correlation_cst and a line in warnings);
they never change the classification. A residual suborder or group named
for the udic regime (the Udic Andosols, Vertosols, Isohumosols, Ferrosols,
Argosols and Cambosols, the Udi- groups) or for the aquic one (the
Aqui-Orthic Halosols) reached by a soil whose regime read is another
keeps its class, with a note. The diagnostic horizons and characteristics
of each layer are in the trace (phase horizons). The readings where
the text is silent are listed in system.file("rules", "cst2001",
"readings.yaml", package = "soilKey").
References
Cooperative Research Group on Chinese Soil Taxonomy (2001). Chinese Soil Taxonomy. Science Press, Beijing and New York.
Examples
res <- classify_cst2001(make_cst2001_example("K3"), on_missing = "silent")
res$name
#> [1] "Typic Argi-Udic Ferrosols"
res$levels
#> level code name
#> 1 orders K Ferrosols
#> 2 suborders K3 Udic Ferrosols
#> 3 groups K3.4 Argi-Udic Ferrosols
#> 4 subgroups K3.4.7 Typic Argi-Udic Ferrosols
#> name_pt book_provisional
#> 1 Ferrossolos (Ferrosols) FALSE
#> 2 Ferrossolos údicos FALSE
#> 3 Ferrossolos údicos argílicos FALSE
#> 4 Ferrossolos údicos argílicos típicos FALSE