Good composition and a great title. I might have cropped a bit more of the grass out - the specks are a bit distracting - but that's being picky... Good.
I love the dune and the white sand contrasting the blue sky. However, with white subjects, there often a bit of overexposure as there seems to be with the middle of the dune.
Very beautiful, love the colour of the sand. I could imagine that cropping this pic leaving only the bottom half would give an wonderfully effective and puristic look.
The ocean distracts from the sand rhythm. I would crop out the top half of the photo and concentrate on the sand and seagrass along the bottom for this challenge.