soil_af {geodata}

Soil data for Africa

Description

Download chemical soil properties data for Africa for different soil depths. The spatial resolution is 30 arc-seconds (about 1 km2), aggregated from the original 250m resolution.

There are more recent estimations for some of the properties available in other data sets. See soil_af_isda and soil_world.

For more info, see https://www.isric.org/projects/soil-property-maps-africa-250-m-resolution

The data have a CC-BY 4.0 NC license

Usage

soil_af(var, depth, path, ...)

Arguments

var

character. Variables name such as "pH" or "clay". See Details

depth

numeric. One of 5, 15, 30, 60, 100, 200. This is shorthand for the following depth ranges: 0-5, 5-15, 15-30, 30-60, 60-100, 100-200 cm. Or one of 20, 50 for 0-20 or 20-50 cm

path

character. Path for storing the downloaded data. See geodata_path

...

additional arguments passed to download.file

Details

	var	description	unit
	clay	Soil texture fraction clay	%
	sand	Soil texture fraction sand	%
	silt	Soil texture fraction silt	%
	coarse	Coarse fragments volumetric	%
	SOC	Organic carbon	g kg-1 (‰)
	BLKD	Bulk density (fine earth)	kg m-3
	poros	Porosity (volum. fraction) based on PTF	-
	AWpF2.0	Avail. soil water capacity (vol. frac.) for FC = pF 2.0	-
	AWpF2.3	Avail. soil water capacity (vol. frac.) for FC = pF 2.3	-
	AWpF2.5	Avail. soil water capacity (vol. frac.) for FC = pF 2.4	-
	AWpF4.2	Avail. soil wat. cap. (vol. frac.) at wilting point (pF 4.2)	-
	BDR	Depth to bedrock	cm
	.	.	.
	pH	pH (H2O)	-
	ECN	Electrical conductivity	mS/m (?)
	acid-exch	Exchangeable acidity	cmol(+) kg-1
	bases-exch	Sum of exchangeable bases	cmol(+) kg-1
	CEC	Cation Exchange Capacity	cmol(+) kg-1
	Al-extr	Extractable Aluminum (Mehlich 3)	mg kg-1 (ppm)
	Al-exch	Exchangeable Aluminum	cmol(+) kg-1
	Ca-exch	Exchangeable Calcium	cmol(+) kg-1
	K-exch	Exchangeable Potassium	cmol(+) kg-1
	Mg-exch	Exchangeable Magnesium	cmol(+) kg-1
	Na-exch	Exchangeable Sodium	cmol(+) kg-1
	Ntot	Total nitrogen	g kg-1

Value

SpatRaster

References

Hengl T, Heuvelink GBM, Kempen B, Leenaars JGB, Walsh MG, Shepherd KD, et al. (2015) Mapping Soil Properties of Africa at 250 m Resolution: Random Forests Significantly Improve Current Predictions. PLoS ONE 10(6): e0125814. doi:10.1371/journal.pone.0125814

See Also

soil_af_elements, soil_af_isda, soil_world_vsi

Examples

# downloads a large file
aph <- soil_af(var="ph", depth=5, path=tempdir())