This is one of the dry pans (there's a specific word for these things but it escapes me) in the middle of the Soussusvlei dunes. Somehow (and there's a more complicated explanation than "rain storms") the things fill up with water every few hundred years. Enough water so that it stays around long enough for trees to grow. And then it all dries up, leaving behind the surreal landscape you see here. These dry pans and their eerie dead trees were featured in one of the nightmare sequences in the movie "The Cell", by the way.