i have to disagree with etoria, the sand looks like sand to me. maybe showing the enlarged size picture can lead people to not visualize it in its original size, which can make them wonder that some shapes are wrong. you should post an original size pic just to not mislead people (just in case).
the sky and sand color (which aren't fully saturated) make this a moody pic. the clouds could have some antialias on the edges (not all of them though), to give them an impression that they're bluring out (practice practice practice)
i just noticed, the left leg has a dark pixel on the highlights side