ssurgo2sp {apsimx}

Take in SSURGO csv files and create a soil profile

Description

Utility function to convert SSURGO data to soil profile

Usage

ssurgo2sp(
  mapunit = NULL,
  component = NULL,
  chorizon = NULL,
  mapunit.shp = NULL,
  nmapunit = 1,
  nsoil = 1,
  xout = NULL,
  soil.bottom = 200,
  method = c("constant", "linear"),
  nlayers = 10,
  verbose = FALSE
)

Arguments

mapunit

mapunit SSURGO file

component

component SSURGO file

chorizon

chorizon SSURGO file

mapunit.shp

mapunit shapefile for creating metadata

nmapunit

number of mapunits to select

nsoil

number of soil components (within a mapunit) to consider

xout

vector for interpolation and extrapolation

soil.bottom

bottom of the soil profile

method

method used for interpolation (see approx)

nlayers

number of soil layers to generate

verbose

whether to print details of the process

Details

Some of the conversions use pedotrasnfer equations from Saxton and Rawls. Soil Water Characteristic Estimates by Texture and Organic Matter for Hydrologic Solutions. Soil Sci. Soc. Am. J. 70:1569–1578 (2006).

Download the data from SSURGO using the ‘FedData’ package
This will generate csv files ‘chorizon’, ‘component’ and ‘mapunit’,
but also many other files which are not needed for creating a soil profile.

Value

a list with soil profile matrices with length equal to nsoil

Examples

require(ggplot2)
require(sf)
extd.dir <- system.file("extdata", package = "apsimx")

chorizon <- read.csv(paste0(extd.dir,"/ISUAG/SSURGO/ISUAG_SSURGO_chorizon.csv"))
component <- read.csv(paste0(extd.dir,"/ISUAG/SSURGO/ISUAG_SSURGO_component.csv"))
mapunit <- read.csv(paste0(extd.dir,"/ISUAG/SSURGO/ISUAG_SSURGO_mapunit.csv"))
mapunit.shp <- st_read(paste0(extd.dir,"/ISUAG/SSURGO/ISUAG_SSURGO_Mapunits.shp"), quiet = TRUE)

## Using default 'constant' method
sp.c <- ssurgo2sp(mapunit = mapunit, 
                 component = component, 
                 chorizon = chorizon, 
                 mapunit.shp = mapunit.shp)

sp.c <- sp.c[[1]]

ggplot(data = sp.c, aes(y = -Depth, x = Carbon)) + 
geom_point() + 
  geom_path() + 
  ylab("Soil Depth (cm)") + xlab("Organic Matter (percent)") +
  ggtitle("method = constant")
  
  
## Using 'linear' method
sp.l <- ssurgo2sp(mapunit = mapunit, 
                 component = component, 
                 chorizon = chorizon, 
                 mapunit.shp = mapunit.shp,
                 method = "linear")
                 
sp.l <- sp.l[[1]]
                 
ggplot(data = sp.l, aes(y = -Depth, x = Carbon)) + 
geom_point() + 
  geom_path() + 
  ylab("Soil Depth (cm)") + xlab("Organic Matter (percent)") +
  ggtitle("Method linear")


## Not run: 
## Method using get_ssurgo_tables

require(soilDB)
require(sp)
require(sf)
require(spData)
## retrieve data from lon -93, lat = 42
stbls <- get_ssurgo_tables(lonlat = c(-93, 42))

sp2.c <- ssurgo2sp(mapunit = stbls$mapunit, 
                 component = stbls$component, 
                 chorizon = stbls$chorizon, 
                 mapunit.shp = stbls$mapunit.shp)  
names(sp2.c)

metadata <- attributes(sp2.c[[1]])
metadata$names <- NULL; metadata$class <- NULL; metadata$row.names <- NULL

## Convert to an APSIM soil profile
asp2.c <- apsimx_soil_profile(nlayers = 10,
                              Thickness = sp2.c[[1]]$Thickness * 10,
                              BD = sp2.c[[1]]$BD,
                              AirDry = sp2.c[[1]]$AirDry,
                              LL15 = sp2.c[[1]]$LL15,
                              DUL = sp2.c[[1]]$DUL,
                              SAT = sp2.c[[1]]$SAT,
                              KS = sp2.c[[1]]$KS,
                              Carbon = sp2.c[[1]]$Carbon,
                              PH = sp2.c[[1]]$PH,
                              ParticleSizeClay = sp2.c[[1]]$ParticleSizeClay,
                              ParticleSizeSilt = sp2.c[[1]]$ParticleSizeSilt,
                              ParticleSizeSand = sp2.c[[1]]$ParticleSizeSand,
                              metadata = metadata)
                              
plot(asp2.c)
plot(asp2.c, property = "water")


## End(Not run)