This function downloads a generalized representation of the geographic extent of any single taxon from the top 4 levels of Soil Taxonomy, or taxa matching a given formative element used in Great Group or subgroup taxa. Data are provided by SoilWeb, ultimately sourced from the current SSURGO snapshot. Data are returned as raster
objects representing area proportion falling within 800m cells. Currently area proportions are based on major components only. Data are only available in CONUS and returned using an Albers Equal Area / NAD83(2011) coordinate reference system (EPSG: 5070).
Arguments
- x
single taxon label (e.g.
haploxeralfs
) or formative element (e.g.pale
), case-insensitive- level
the taxonomic level within the top 4 tiers of Soil Taxonomy, one of
'order'
,'suborder'
,'greatgroup'
,'subgroup'
- formativeElement
logical, search using formative elements instead of taxon label
- timeout
time that we are willing to wait for a response, in seconds
- as_Spatial
Return raster (
RasterLayer
) classes? Default:FALSE
.
Details
See the Geographic Extent of Soil Taxa tutorial for more detailed examples.
Taxon Queries
Taxon labels can be conveniently extracted from the "ST_unique_list"
sample data, provided by the SoilTaxonomy package.
Formative Element Queries
Greatgroup:
The following labels are used to access taxa containing the following formative elements (in parentheses)
acr: (acro/acr) extreme weathering
alb: (alb) presence of an albic horizon
anhy: (anhy) very dry
anthra: (anthra) presence of an anthropic epipedon
aqu: (aqui/aqu) wetness
argi: (argi) presence of an argillic horizon
calci: (calci) presence of a calcic horizon
cry: (cryo/cry) cryic STR
dur: (duri/dur) presence of a duripan
dystr: (dystro/dystr) low base saturation
endo: (endo) ground water table
epi: (epi) perched water table
eutr: (eutro/eutr) high base saturation
ferr: (ferr) presence of Fe
fibr: (fibr) least decomposed stage
fluv: (fluv) flood plain
fol: (fol) mass of leaves
fragi: (fragi) presence of a fragipan
fragloss: (fragloss) presence of a fragipan and glossic horizon
frasi: (frasi) not salty
fulv: (fulvi/fulv) dark brown with organic carbon
glac: (glac) presence of ice lenses
gloss: (glosso/gloss) presence of a glossic horizon
gypsi: (gypsi) presence of a gypsic horizon
hal: (hal) salty
hemi: (hemi) intermediate decomposition
hist: (histo/hist) organic soil material
hum: (humi/hum) presence of organic carbon
hydr: (hydro/hydr) presence of water
kandi: (kandi) presence of a kandic horizon
kanhap: (kanhaplo/kanhap) thin kandic horizon
luvi: (luvi) illuvial organic material
melan: (melano/melan) presence of a melanic epipedon
moll: (molli/moll) presence of a mollic epipedon
natr: (natri/natr) presence of a natric horizon
pale: (pale) excessive development
petr: (petro/petr) petrocalcic horizon
plac: (plac) presence of a thin pan
plagg: (plagg) presence of a plaggen epipedon
plinth: (plinth) presence of plinthite
psamm: (psammo/psamm) sandy texture
quartzi: (quartzi) high quartz content
rhod: (rhodo/rhod) dark red colors
sal: (sali/sal) presence of a salic horizon
sapr: (sapr) most decomposed stage
sombri: (sombri) presence of a sombric horizon
sphagno: (sphagno) presence of sphagnum moss
sulf: (sulfo/sulfi/sulf) presence of sulfides or their oxidation products
torri: (torri) torric/aridic SMR
ud: (udi/ud) udic SMR
umbr: (umbri/umbr) presence of an umbric epipedon
ust: (usti/ust) ustic SMR
verm: (verm) wormy, or mixed by animals
vitr: (vitri/vitr) presence of glass
xer: (xero/xer) xeric SMR
Subgroup:
The following labels are used to access taxa containing the following formative elements (in parenthesis).
abruptic: (abruptic) abrupt textural change
acric: (acric) low apparent CEC
aeric: (aeric) more aeration than typic subgroup
albaquic: (albaquic) presence of albic minerals, wetter than typic subgroup
albic: (albic) presence of albic minerals
alfic: (alfic) presence of an argillic or kandic horizon
alic: (alic) high extractable Al content
anionic: (anionic) low CEC or positively charged
anthraquic: (anthraquic) human controlled flooding as in paddy rice culture
anthropic: (anthropic) an anthropic epipedon
aquic: (aquic) wetter than typic subgroup
arenic: (arenic) 50-100cm sandy textured surface
argic: (argic) argillic horizon
aridic: (aridic) more aridic than typic subgroup
calcic: (calcic) presence of a calcic horizon
chromic: (chromic) high chroma colors
cumulic: (cumulic) thickened epipedon
duric: (duric) presence of a duripan
durinodic: (durinodic) presence of durinodes
dystric: (dystric) lower base saturation percentage
entic: (entic) minimal surface/subsurface development
eutric: (eutric) higher base saturation percentage
fibric: (fibric) >25cm of fibric material
fluvaquentic: (fluvaquentic) wetter than typic subgroup, evidence of stratification
fragiaquic: (fragiaquic) presence of fragic properties, wetter than typic subgroup
fragic: (fragic) presence of fragic properties
glacic: (glacic) presence of ice lenses or wedges
glossaquic: (glossaquic) interfingered horizon boundaries, wetter than typic subgroup
glossic: (glossic) interfingered horizon boundaries
grossarenic: (grossarenic) >100cm sandy textured surface
gypsic: (gypsic) presence of gypsic horizon
halic: (halic) salty
haplic: (haplic) central theme of subgroup concept
hemic: (hemic) >25cm of hemic organic material
humic: (humic) higher organic matter content
hydric: (hydric) presence of water
kandic: (kandic) low activity clay present
lamellic: (lamellic) presence of lamellae
leptic: (leptic) thinner than typic subgroup
limnic: (limnic) presence of a limnic layer
lithic: (lithic) shallow lithic contact present
natric: (natric) presence of sodium
nitric: (nitric) presence of nitrate salts
ombroaquic: (ombroaquic) surface wetness
oxyaquic: (oxyaquic) water saturated but not reduced
pachic: (pachic) epipedon thicker than typic subgroup
petrocalcic: (petrocalcic) presence of a petrocalcic horizon
petroferric: (petroferric) presence of petroferric contact
petrogypsic: (petrogypsic) presence of a petrogypsic horizon
petronodic: (petronodic) presence of concretions and/or nodules
placic: (placic) presence of a placic horizon
plinthic: (plinthic) presence of plinthite
rhodic: (rhodic) darker red colors than typic subgroup
ruptic: (ruptic) intermittent horizon
salic: (salic) presence of a salic horizon
sapric: (sapric) >25cm of sapric organic material
sodic: (sodic) high exchangeable Na content
sombric: (sombric) presence of a sombric horizon
sphagnic: (sphagnic) sphagnum organic material
sulfic: (sulfic) presence of sulfides
terric: (terric) mineral substratum within 1 meter
thapto: (thaptic/thapto) presence of a buried soil horizon
turbic: (turbic) evidence of cryoturbation
udic: (udic) more humid than typic subgroup
umbric: (umbric) presence of an umbric epipedon
ustic: (ustic) more ustic than typic subgroup
vermic: (vermic) animal mixed material
vitric: (vitric) presence of glassy material
xanthic: (xanthic) more yellow than typic subgroup
xeric: (xeric) more xeric than typic subgroup
Examples
if (FALSE) { # \dontrun{
library(terra)
# soil order
taxa <- 'vertisols'
x <- taxaExtent(taxa, level = 'order')
# suborder
taxa <- 'ustalfs'
x <- taxaExtent(taxa, level = 'suborder')
# greatgroup
taxa <- 'haplohumults'
x <- taxaExtent(taxa, level = 'greatgroup')
# subgroup
taxa <- 'Typic Haploxerepts'
x <- taxaExtent(taxa, level = 'subgroup')
# greatgroup formative element
taxa <- 'psamm'
x <- taxaExtent(taxa, level = 'greatgroup', formativeElement = TRUE)
# subgroup formative element
taxa <- 'abruptic'
x <- taxaExtent(taxa, level = 'subgroup', formativeElement = TRUE)
# coarsen for faster plotting
a <- terra::aggregate(x, fact = 5, na.rm = TRUE)
# quick evaluation of the result
terra::plot(a, axes = FALSE)
} # }