reclassDist: Reclassify natural disturbance and harvest layers

In LandSciTech/caribouMetrics: Models and Metrics of Boreal Caribou Demography and Habitat Selection

Reclassify natural disturbance and harvest layers

Description

Classify disturbances that have occurred in a user defined time period. The output from this function can be used as either the natDist or anthroDist inputs for caribouMetrics() or disturbanceMetrics().

Usage

reclassDist(distYr, endYr = 0, numCumYrs, template, dateField)

Arguments

distYr	sf object, SpatRaster or RasterLayer. A simple feature collection or raster layer covering the focal area and including the year of disturbance or time since disturbance as well as geometry (multipolygon) of the disturbance.
endYr	numeric default 0. Four digit year indicating the latest year to include from distYr. If 0 assume dateField values indicate time since disturbance.
numCumYrs	numeric. Number of years before endYr to include.
template	SpatRaster or RasterLayer. A raster of the focal region, used as a template to which disturbance information is projected. This layer's dimensions determine the dimensions of the output. It is recommended to use the landCover raster layer used in caribouMetrics() or disturbanceMetrics() to ensure equal dimensions
dateField	character. Name of the column in which disturbance year/time since disturbance is recorded.

Value

Returns a binary SpatRaster with the same dimensions as the template input. Values of 1 represent areas of disturbance

See Also

Functions for calculating disturbance: DisturbanceMetrics-class, disturbanceMetrics(), results(), updateDisturbance()

Examples

library(sf)
# create template raster
lc <- terra::rast(nrows = 10, ncols = 10, xmin = 0, xmax = 10, ymin = 0,
                  ymax = 10, crs = "EPSG:5070")

# create fire polygons 
corners <- matrix(c(0,0,10,10,5, 0,10,10,0,5), ncol = 2)

fireYr <- st_sf(FIRE_YEAR = c(1990, 2000, 2009, 2015),
                     geometry = st_sfc(st_polygon(list(corners[c(1,2,5, 1),])),
                                       st_polygon(list(corners[c(2,3,5, 2),])),
                                       st_polygon(list(corners[c(3,4,5, 3),])),
                                       st_polygon(list(corners[c(4,1,5, 4),])))) 
fireYr <- st_set_crs(fireYr, 5070)

# three polygons should be considered disturbed (1) but the 2015 polygon should
# not (0)
cumFirePresence <- reclassDist(fireYr,
                               endYr = 2010,
                               numCumYrs = 40,
                               template = lc,
                               dateField = "FIRE_YEAR")

plot(cumFirePresence)

# with time since disturbance
fireYr$FIRE_YEAR <- c(50, 15, 10, 20)
cumFirePresence2 <- reclassDist(fireYr,
                               endYr = 0,
                               numCumYrs = 40,
                               template = lc,
                               dateField = "FIRE_YEAR")
                               
plot(cumFirePresence2)

LandSciTech/caribouMetrics documentation built on Feb. 3, 2024, 9:41 p.m.