Why are fired important to prairies but not important to dunes?

Fires are important to praires because the help to return nutrients to the soil and help the praires get to a climax community, sand dunes on the other hand arent in need of fire because fire cant restore nutrients (if there is any) to sand and most vegetation for sand dunes are adapted to what they can get from sand dunes. in conclusion, fires are important to prairies because they restore nutrients which in turn restores a better environment (vegetation) but because sand dunes are a different environment, they dont need fires to thrive