fetchOSD {soilDB}

Get Official Series Descriptions and summaries from SoilWeb API

Description

This function fetches a variety of data associated with named soil series, extracted from the USDA-NRCS Official Series Description text files and detailed soil survey (SSURGO). These data are updated quarterly and made available via SoilWeb. Set extended = TRUE and see the soilweb.metadata list element for information on when the source data were last updated.

Usage

fetchOSD(soils, colorState = "moist", extended = FALSE)

Arguments

soils

a character vector of named soil series; case-insensitive

colorState

color state for horizon soil color visualization: "moist" or "dry"

extended

if TRUE additional soil series summary data are returned, see details

Details

• overview of all soil series query functions

• competing soil series

• siblings

The standard set of "site" and "horizon" data are returned as a SoilProfileCollection object (extended = FALSE). The "extended" suite of summary data can be requested by setting extended = TRUE. The resulting object will be a list with the following elements:

SPC

SoilProfileCollection containing standards "site" and "horizon" data

competing

competing soil series from the SC database snapshot

geog_assoc_soils

geographically associated soils, extracted from named section in the OSD

geomcomp

empirical probabilities for geomorphic component, derived from the current SSURGO snapshot

hillpos

empirical probabilities for hillslope position, derived from the current SSURGO snapshot

mtnpos

empirical probabilities for mountain slope position, derived from the current SSURGO snapshot

terrace

empirical probabilities for river terrace position, derived from the current SSURGO snapshot

flats

empirical probabilities for flat landscapes, derived from the current SSURGO snapshot

shape_across

empirical probabilities for surface shape (across-slope) from the current SSURGO snapshot

shape_down

empirical probabilities for surface shape (down-slope) from the current SSURGO snapshot

pmkind

empirical probabilities for parent material kind, derived from the current SSURGO snapshot

pmorigin

empirical probabilities for parent material origin, derived from the current SSURGO snapshot

mlra

empirical MLRA membership values, derived from the current SSURGO snapshot

ecoclassid

area cross-tabulation of ecoclassid by soil series name, derived from the current SSURGO snapshot, major components only

climate

experimental climate summaries from PRISM stack (CONUS only)

NCCPI

select quantiles of NCCPI and Irrigated NCCPI, derived from the current SSURGO snapshot

metadata

metadata associated with SoilWeb cached summaries

When using extended = TRUE, there are a couple of scenarios in which series morphology contained in SPC do not fully match records in the associated series summary tables (e.g. competing).

1. A query for soil series that exist entirely outside of CONUS (e.g. PALAU).

- Climate summaries are empty data.frames because these summaries are currently generated from PRISM. We are working on a solution that uses DAYMET.

2. A query for data within CONUS, but OSD morphology missing due to parsing error (e.g. formatting, typos).

- Extended summaries are present but morphology missing from SPC. A warning is issued.

These last two cases are problematic for analysis that makes use of morphology and extended data, such as outlined in this tutorial on competing soil series.

Value

a SoilProfileCollection object containing basic soil morphology and taxonomic information.

Note

Requests to the SoilWeb API are split into batches of 100 series names from soils via makeChunks().

Author(s)

D.E. Beaudette, A.G. Brown

References

USDA-NRCS OSD search tools: https://soilseries.sc.egov.usda.gov/

See Also

OSDquery(), siblings()

Examples

  library(aqp)
  # soils of interest
  s.list <- c('musick', 'cecil', 'drummer', 'amador', 'pentz',
              'reiff', 'san joaquin', 'montpellier', 'grangeville', 'pollasky', 'ramona')

  # fetch and convert data into an SPC
  s.moist <- fetchOSD(s.list, colorState='moist')
  s.dry <- fetchOSD(s.list, colorState='dry')

  # plot profiles
  # moist soil colors
  par(mar=c(0,0,0,0), mfrow=c(2,1))
  plot(s.moist, name='hzname',
       cex.names=0.85, axis.line.offset=-4)
  plot(s.dry, name='hzname',
       cex.names=0.85, axis.line.offset=-4)

  # extended mode: return a list with SPC + summary tables
  x <- fetchOSD(s.list, extended = TRUE, colorState = 'dry')

  par(mar=c(0,0,1,1))
  plot(x$SPC)
  str(x, 1)