ForestGapR (version 0.0.2)

GapSPDF: Forest Canopy Gaps as Spatial Polygons

Description

This function converts forest canopy gaps as RasterLayer (raster) to SpatialPointsDataFrame-class objects

Usage

GapSPDF(gap_layer)

Arguments

gap_layer

ALS-derived gap layer (output of getForestGaps function). An object of the classs RasterLayer.

Value

A SpatialPointsDataFrame-class object of the forest canopy gaps. The output file can be exported as a ESRI shapefile using writeOGR function in the rgdal package.

Examples

# NOT RUN {
#Loading raster and viridis libraries
library(raster)
library(viridis)

# ALS-derived CHM over Adolpho Ducke Forest Reserve - Brazilian tropical forest
data(ALS_CHM_DUC)

# set height thresholds (e.g. 10 meters)
threshold<-10
size<-c(1,10^4) # m2

# Detecting forest gaps
gaps_duc<-getForestGaps(chm_layer=ALS_CHM_DUC, threshold=threshold, size=size)

# Converting raster layer to SpatialPolygonsDataFrame
gaps_spdf<-GapSPDF(gap_layer=gaps_duc)

# Plotting ALS-derived CHM and forest gaps
plot(ALS_CHM_DUC, col=viridis(10), xlim=c(173025,173125), ylim=c(9673100,96731200))
plot(gaps_spdf, add=TRUE, border="red", lwd=2)

# Populating the attribute table of Gaps_spdf with gaps statistics
gaps_stats<-GapStats(gap_layer=gaps_duc, chm_layer=ALS_CHM_DUC)
gaps_spdf<-merge(gaps_spdf,gaps_stats, by="gap_id")
head(gaps_spdf@data)
# }