Hello,
For some reason, gsettings is not working on my installation—ubuntu 16.04 MATE 64-bit. Specifically, a command similar to
$ gsettings set org.mate.background picture-filename ‘/usr/share/backgrounds/mate/abstract/Spring.png’
has no effect. On the other hand, the wallpaper changes if I make the changes with dconf editor. It also changes if I change wallpaper via System > Look and Feel > Appearance
I need gsettings to work, because variety (a wallpaper-changer s/w) depends on it…