GIFT_no_overlap {GIFT}

Select non-overlapping regions

Description

Identify overlapping regions in a set of GIFT regions and choose only non-overlapping regions based on size and overlap criteria

Usage

GIFT_no_overlap(
  entity_IDs = NULL,
  area_threshold_island = 0,
  area_threshold_mainland = 100,
  overlap_threshold = 0.1,
  geoentities_overlap = NULL,
  api = "https://gift.uni-goettingen.de/api/extended/",
  GIFT_version = "latest"
)

Arguments

entity_IDs

A vector of IDs of the regions for which we want to check overlap

area_threshold_island

A number stating from which surface the smallest overlapping polygon is kept. By default set to 0 square kilometer (meaning that by default the smallest islands will be conserved).

area_threshold_mainland

When two polygons overlap, the smallest or the biggest one can be kept. When the surface of the smallest polygon exceeds this number, the smallest polygon is kept. Otherwise, we keep the bigger one. Set by default 100 square-kilometers.

overlap_threshold

A number ranging from 0 to 1, indicating at what percentage of overlap, partially overlapping polygons should be kept.

geoentities_overlap

A table coming from GIFT indicating the overlap in km^2 between pairs of polygons.

api

character string defining from which API the data will be retrieved.

GIFT_version

character string defining the version of the GIFT database to use. The function retrieves by default the latest stable version. If set to beta, the most up-to-date version which is still subject to changes and edits is used.

Value

A vector of entity_IDs (identification numbers of polygons) non-overlapping.

References

 Denelle, P., Weigelt, P., & Kreft, H. (2023). GIFT—An R package to
 access the Global Inventory of Floras and Traits. Methods in Ecology
 and Evolution, 14, 2738-2748.
 https://doi.org/10.1111/2041-210X.14213

 Weigelt, P, König, C, Kreft, H. GIFT – A Global Inventory of Floras and
 Traits for macroecology and biogeography. J Biogeogr. 2020; 47: 16– 43.
 https://doi.org/10.1111/jbi.13623

See Also

GIFT_checklists()

Examples

ex <- GIFT_no_overlap(entity_IDs = c(10071, 12078)) # Andalusia and Spain. 
# We get Andalusia because it is smaller than Spain and larger than 100 km²
ex2 <- GIFT_no_overlap(entity_IDs = c(10071, 12078), 
area_threshold_mainland = 100000) # since Andalusia is smaller than
# 100,000 km² large, the larger entity (Spain) is chosen here.