Spar-SE, like its opposite den-SE, is that kind of word you can’t describe exactly. It’s a cheeky adjective, you wouldn’t use it much. You’d rather to scatter few attempts first. Scanty, sporadic, infrequent perhaps are better choices. Widely spaced, thinly distributed little (or big) objects, to give you a sense of space. A sense of isolation, loneliness for the items spotted in the great white (or black) of all that emptiness.