DrK-Lo

ggtheme <- theme_bw() + theme(panel.grid.major = element_blank(), panel.grid.minor = element_blank(), panel.background = element_blank(), panel.border=element_blank(), axis.line = element_line(colour="grey30"), axis.title = element_text(colour="grey20"), axis.text = (element_text(colour="grey30")), legend.title = element_text(colour="grey20"), legend.text = element_text(colour="grey30"))

to use it, just use:

ggplot(data) + geom_point(aes(x=x, y=y)) + ggtheme

DrK-Lo

par(xpd=NA, oma=c(4,0,0,0), mar=c(2,4,0,0),mfrow=c(1,1))  
plot(1,1, xlim=c(-1,1), ylim=c(0,1))
# This is for a plot with x-axis from -1 to 1 and y axis from 0 to 1. It plots a legend in the bottom margin
legend(-1,-0.25,  legend=c("high sal.", "low sal."), bty="n", adj=0, fill=c("grey", NA), horiz=TRUE)

DrK-Lo

packages_needed <- c("raster", "FNN", "RColorBrewer", "colorRamps", "adehabitatLT",
                     "data.table", "tidyverse", "fields", "ggplot2", "hexbin",
                     "rgdal", "tmap", "gstat", "sp", "maptools", "sf", "fasterize",
                     "fansi", "raster", "tmap", "gstat", "ContourFunctions","ash"
                     )

for (i in 1:length(packages_needed)){
  if(!(packages_needed[i] %in% installed.packages())){install.packages(packages_needed[i])}
}