ForestGapR (version 0.1.7)

GapChangeDec: Forest Gaps Change Detection

Description

This function detects forest canopy gap changes across two forest gap raster::RasterLayer objects

Usage

GapChangeDec(gap_layer1,gap_layer2)

Value

A raster::RasterLayer object representing forest gap change area

Arguments

gap_layer1

ALS-derived gap as an raster::RasterLayer object at time 1. (output of getForestGaps() function).

gap_layer2

ALS-derived gap as an raster::RasterLayer object at time 2. (output of getForestGaps() function).

Author

Carlos Alberto Silva.

Examples

if (FALSE) {
# Loading raster and viridis libraries
library(raster)
library(viridis)


# ALS-derived CHM from Fazenda Cauxi - Brazilian tropical forest
data(ALS_CHM_CAU_2012)
data(ALS_CHM_CAU_2014)

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

# Detecting forest gaps
gaps_cau2012 <- getForestGaps(chm_layer = ALS_CHM_CAU_2012, threshold = threshold, size = size)
gaps_cau2014 <- getForestGaps(chm_layer = ALS_CHM_CAU_2014, threshold = threshold, size = size)

# Detecting forest gaps changes
Gap_changes <- GapChangeDec(gap_layer1 = gaps_cau2012, gap_layer2 = gaps_cau2014)

# Plotting ALS-derived CHM and forest gaps
oldpar <- par(mfrow = c(1, 3))
plot(ALS_CHM_CAU_2012, main = "Forest Canopy Gap - 2012", col = viridis(10))
plot(gaps_cau2012, add = TRUE, col = "red", legend = FALSE)

plot(ALS_CHM_CAU_2014, main = "Forest Canopy Gap - 2014", col = viridis(10))
plot(gaps_cau2014, add = TRUE, col = "red", legend = FALSE)

plot(ALS_CHM_CAU_2014, main = "Forest Gap Changes Detected", col = viridis(10))
plot(Gap_changes, add = TRUE, col = "orange", legend = FALSE)
par(oldpar)
}