ggsoiltexture

The goal of ggsoiltexture is to provide a simple ggplot function for the plotting of soil textural data. It is still in development, mainly for use in pubs. If you use this package please cite this repository. Hope it is useful!

Acknowledgement

The code was development based on the ggplot_piper functions written by Jonh Dorian and inspired by the R package ggtern. Thanks for sharing your knowledge.

Installation

You can install the ggsoiltexture v1.0 from GitHub with:

# install.packages("devtools")
devtools::install_github("Saryace/ggsoiltexture")

What do you need?

Dataframe or tibble with three variables called:

• sand, as percentage
• silt, as percentage
• clay, as percentage

More info

• Visit the lab's YT channel

Main functions:

ggsoiltexture

This function plots soil texture in a ternary plot.

Tutorial

Data

Your data must to sum up 100%. The function will stop if it is not checked previously

library(tidyverse)
library(ggsoiltexture)
fail_data <- data.frame(
              clay = c(100,20,25,20,10),
              silt  = c(35,150,45,30,40),
              sand = c(55.65,30,0,500,50))

ggsoiltexture(fail_data)

Error in ggsoiltexture(fail_data) : 
  Some of your textural data do not sum 100%, please check.!

Simple plot

A simple plot can be done directly

some_data <- data.frame(id = c("A","B","C","D","E"),
                          clay = c(10,20,25,20,10),
                          silt  = c(35,15,45,30,40),
                          sand = c(55,65,30,50,50),
                          om = c(5,15,5,12,7))

another_plot <-
ggsoiltexture(some_data)

another_plot

Adding more layers

Because ggsoiltexture is based on ggplot2, more geoms, themes, can be added

pub_plot <-
    ggsoiltexture(some_data) +
    geom_point(aes(color = om), size = 6) +
    scale_color_continuous(type = "viridis") +
    labs(color = "Organic\nMatter (%)") +
    geom_label_repel(aes(label = id), box.padding = 0.5) +
    theme(legend.title = element_text(face = "bold"),
          legend.position = "bottom")

pub_plot 

Adding USDA classification system

Using geom_polygon, a layer showing the USDA classes can be added.

# load the USDA polygon info

data(usda_polygons)

# then plot

usda_plot <-
ggsoiltexture(some_data) +
  geom_polygon(
    data = usda_polygons,
    aes(fill = label),
    alpha = 0.0,
    size = 0.5,
    color = "black"
  ) +
  geom_text(data = usda_polygons  %>% group_by(label) %>%
              summarise_if(is.numeric, mean, na.rm = TRUE),
            aes(label = label),
            color = 'black',
            size = 3) +
  theme(legend.position = "none")