wdpa_fetch: Fetch data

In wdpar: Interface to the World Database on Protected Areas

Fetch data

Description

Fetch data from Protected Planet. Specifically, data are downloaded from the World Database on Protected Areas (WDPA) and the World Database on Other Effective Area-Based Conservation Measures (WDOECM). Note that data are downloaded assuming non-commercial use.

Usage

wdpa_fetch(
  x,
  wait = FALSE,
  download_dir = tempdir(),
  force_download = FALSE,
  check_version = TRUE,
  n = NULL,
  page_wait = 2,
  datatype = "gdb",
  verbose = interactive()
)

Arguments

x	character country for which to download data. This argument can be the name of the country (e.g. "Liechtenstein") or the ISO-3 code for the country (e.g. "LIE"). This argument can also be set to "global" to download all of the protected areas available in the database (approximately 1.1 GB).
wait	logical if data is not immediately available for download should the session be paused until it is ready for download? If argument to wait is FALSE and the data is not ready then NA will be returned. Defaults to FALSE.
download_dir	character folder path to download the data. Defaults to a temporary directory. To avoid downloading the same dataset multiple times, it is recommended to use a persistent directory (e.g. rappdirs::user_data_dir("wdpar"); see Examples below).
force_download	logical if the data has previously been downloaded and is available at argument to download_dir, should a fresh copy be downloaded? Defaults to FALSE.
check_version	logical if the data are being imported from from the argument to download_dir, should the data be checked to see if the version number matches the latest version available online? Defaults to TRUE.
n	integer number of records to import per data source. Defaults to NULL such that all data are imported.
page_wait	numeric number of seconds to wait for web pages to load when finding the download URL on Protected Planet. Defaults to 2. Since the process of finding a download URL requires navigating through multiple web pages, the default argument means that the function will take at least 8 seconds to complete. Users on slow internet connections may experience issues with the default argument (e.g. resulting in an error containing the message Error: Summary: NoSuchElement). To avoid this, users can try specifying a greater value (e.g. 5 seconds).
datatype	character denoting the file format for which to download protected area data. Available options include: ("shp") shapefile format and ("gdb") file geodatabase format. Defaults to '"gdb". Note that global data are only available in file geodatabase format.
verbose	logical should a progress on downloading data be reported? Defaults to TRUE in an interactive session, otherwise FALSE.

Details

This function obtains and imports data from Protected Planet. By default (per force_download = FALSE), it will check to see if the data have already been downloaded and, if so, simply import the previously downloaded data. It will also check to see if a newer version of the dataset is available on Protected Planet (per check_version = TRUE) and, if so, provide an alert. If the latest version is not required, this alert can be safely ignored. However, if the latest version of the data is required, then using force_download = TRUE will ensure that the latest version is always obtained. After importing the data, it is strongly recommended to clean the data prior to analysis (see wdpa_clean()).

Value

A sf::sf() object.

Data source

The PA_DEF column indicates the data source for individual areas and sites that comprise the imported dataset. Specifically, data obtained through the World Database on Protected Areas (WDPA) are indicated with a value of 1 in the PA_DEF column. Additionally, data obtained through the World Database on Other Effective Area-Based Conservation Measures (WDOECM) are indicated with a value of 0 in the PA_DEF column. For more details on data conventions, please consult the official manual (UNEP-WCMC 2019).

Troubleshooting

The function requires a Chromium-based browser (e.g., Google Chrome, Chromium, or Brave) to be installed. This is because it uses the chromote to find the URL for downloading data from Protected Planet. If you don't have one of these browsers installed, then please try installing Google Chrome. If you do have one of these browsers installed and this function throws an error indicating that it can't find the browser, try setting the CHROMOTE_CHROME environment variable to the file path of the executable. For example, you could do this with:

Sys.setenv(CHROMOTE_CHROME = "INSERT_FILE_PATH_HERE.exe")

Also, the function will sometimes produce a message that complains about a handle_read_frame error. Please understand that this message is, in fact, not an error and can be safely ignored (see https://github.com/rstudio/chromote/pull/111). As such, if you see this message when running the function, you can assume that the function still worked correctly. For reference, the misleading message will look something like this:

[error] handle_read_frame error: websocketpp.transport:7 (End of File)

For further help with troubleshooting, please refer to the documentation for the chromote package (https://rstudio.github.io/chromote/).

References

UNEP-WCMC (2019). User Manual for the World Database on Protected Areas and world database on other effective area-based conservation measures: 1.6. UNEP-WCMC: Cambridge, UK. Available at: https://wcmc.io/WDPA_Manual.

See Also

wdpa_clean(), wdpa_read(), wdpa_url(), countrycode::countrycode().

Examples

## Not run: 
# fetch data for Liechtenstein
lie_raw_data <- wdpa_fetch("Liechtenstein", wait = TRUE)

# print data
print(lie_raw_data)

# plot data
plot(lie_raw_data)

# fetch data for Liechtenstein using the ISO3 code
lie_raw_data <- wdpa_fetch("LIE", wait = TRUE)

# since data are saved in a temporary directory by default,
# a persistent directory can be specified to avoid having to download the
# same dataset every time the R session is restarted
lie_raw_data <- wdpa_fetch("LIE", wait = TRUE,
                           download_dir = rappdirs::user_data_dir("wdpar"))

# data for multiple countries can be downloaded separately and combined,
# this is useful to avoid having to download the global dataset
## load packages to easily merge datasets
library(dplyr)
library(tibble)

## define country names to download
country_codes <- c("LIE", "MHL")

## download data for each country
mult_data <- lapply(country_codes, wdpa_fetch, wait = TRUE)

## merge datasets together
mult_dat <- st_as_sf(as_tibble(bind_rows(mult_data)))

## print data
print(mult_dat)

## End(Not run)

wdpar documentation built on Oct. 7, 2024, 9:07 a.m.