soilDB (version 2.4.1)

us_ss_timeline: Timeline of US Published Soil Surveys

Description

This dataset contains the years of each US Soil Survey was published.

Usage

data("us_ss_timeline")

Format

A data frame with 5209 observations on the following 5 variables.

ssa

Soil Survey name, a character vector

year

year of publication, a numeric vector

pdf

does a pdf exists, a logical vector

state

State abbrevation, a character vector

Details

This data was web scraped from the NRCS Soils Website. The scraping procedure and a example plot are included in the examples section below.

Examples

# NOT RUN {
if (
  requireNamespace("XML", quietly = TRUE) & 
  requireNamespace("RCurl", quietly = TRUE) &
  requireNamespace("ggplot2", quietly = TRUE) & 
  requireNamespace("gridExtra", quietly = TRUE)
) {
  
  data(state)
  st <- paste0(c(state.abb, "PR", "DC", "VI", "PB"))
  us_ss_timeline <- {
    lapply(st, function(x) {
      cat("getting", x, "\n")
      url <- getURL(paste0(
        "https://www.nrcs.usda.gov/wps/portal/nrcs/surveylist/soils/survey/state/?stateId=", x)
      )
      df  <- readHTMLTable(url, which = 22, stringsAsFactors = FALSE)
      df$state <- x
      return(df)
    }) ->.;
    do.call("rbind", .) ->.;
    names(.) <- c("ssa", "year", "pdf", "wss", "state")
    .[.$year != "current", ] ->.;
  }
  us_ss_timeline <- within(us_ss_timeline, {
    ssa  = sapply(ssa, function(x) strsplit(x, "\r")[[1]][1])
    year = as.numeric(year)
    pdf  = ifelse(pdf == "Yes", TRUE, FALSE)
    wss  = NULL
  })
  
  test <- as.data.frame(table(us_ss_timeline$year), stringsAsFactors = FALSE)
  
  g1 <- ggplot(test, aes(x = as.numeric(Var1), y = Freq)) +
    geom_histogram(stat = "identity") + 
    xlab("Year") + 
    ylab("Count") +
    theme(aspect.ratio = 1) + 
    ggtitle("Number of Published \n US Soil Surveys by Year")
  g2 <- ggplot(test, aes(x = as.numeric(Var1), y = cumsum(Freq))) +
    geom_histogram(stat = "identity") + 
    xlab("Year") + 
    ylab("Count") +
    theme(aspect.ratio = 1) +
    ggtitle("Cumulative Number of Published \n US Soil Surveys by Year")
  
  grid.arrange(g1, g2, ncol = 2)
  
}


# }