R: GEMAS geochemical data set

gemas {robCompositions} | R Documentation

## GEMAS geochemical data set

### Description

Geochemical data set on agricultural and grazing land soil

### Usage

    data(gemas)

### Format

A data frame with 2108 observations and 30 variables

### Details

- `COUNTRY` country name

- `longitude` longitude in WGS84

- `latitude` latitude in WGS84

- `Xcoord` UTM zone east

- `Ycoord` UTM zone north

- `MeanTemp`Annual mean temperature

- `AnnPrec` Annual mean precipitation

- `soilclass` soil class

- `sand` sand

- `silt` silt

- `clay` clay

- `Al` Concentration of aluminum (in mg/kg)

- `Ba` Concentration of barium (in mg/kg)

- `Ca` Concentration of calzium (in mg/kg)\

- `Cr` Concentration of chromium (in mg/kg)

- `Fe` Concentration of iron (in mg/kg)

- `K` Concentration of pottasium (in mg/kg)

- `Mg` Concentration of magnesium (in mg/kg)

- `Mn` Concentration of manganese (in mg/kg)

- `Na` Concentration of sodium (in mg/kg)

- `Nb` Concentration of niobium (in mg/kg)

- `Ni` Concentration of nickel (in mg/kg)

- `P` Concentration of phosphorus (in mg/kg)

- `Si` Concentration of silicium (in mg/kg)

- `Sr` Concentration of strontium (in mg/kg)

- `Ti` Concentration of titanium (in mg/kg)

- `V` Concentration of vanadium (in mg/kg)\

- `Y` Concentration of yttrium (in mg/kg)

- `Zn` Concentration of zinc (in mg/kg)

- `Zr` Concentration of zirconium (in mg/kg)

- `LOI` Loss on ignition (in wt-percent)

The sampling, at a density of 1 site/2500 sq. km, was completed at the beginning of 2009 by collecting 2211 samples of agricultural soil (Ap-horizon, 0-20 cm, regularly ploughed fields), and 2118 samples from land under permanent grass cover (grazing land soil, 0-10 cm), according to an agreed field protocol. All GEMAS project samples were shipped to Slovakia for sample preparation, where they were air dried, sieved to <2 mm using a nylon screen, homogenised and split to subsamples for analysis. They were analysed for a large number of chemical elements. In this sample, the main elements by X-ray fluorescence are included as well as the composition on sand, silt, clay.

### Author(s)

GEMAS is a cooperation project between the EuroGeoSurveys Geochemistry Expert Group and Eurometaux. Integration in R, Peter Filzmoser and Matthias Templ.

### References

Reimann, C., Birke, M., Demetriades, A., Filzmoser, P. \& O'Connor, P. (Editors), 2014. Chemistry of Europe's agricultural soils - Part A: Methodology and interpretation of the GEMAS data set. Geologisches Jahrbuch (Reihe B 102), Schweizerbarth, Hannover, 528 pp. + DVD Reimann, C., Birke, M., Demetriades, A., Filzmoser, P. & O'Connor, P. (Editors), 2014. Chemistry of Europe's agricultural soils - Part B: General background information and further analysis of the GEMAS data set. Geologisches Jahrbuch (Reihe B 103), Schweizerbarth, Hannover, 352 pp.

### Examples

    data(gemas)
    str(gemas)
    ## sample sites
    ## Not run:
    require(ggmap)
    map <- get_map("europe", source = "stamen", maptype = "watercolor", zoom=4)
    ggmap(map) + geom_point(aes(x=longitude, y=latitude), data=gemas)
    map <- get_map("europe", zoom=4)
    ggmap(map) + geom_point(aes(x=longitude, y=latitude), data=gemas, size=0.8)

    ## End(Not run)

[Package robCompositions version 2.1.0 Index]