Hey, congrats!  Hopefully it is just the start of a flood of dls for you!  No, that's not the one you would expect to be first is it?  You have some very lovely shots on DT.

There are some things to like here, although I agree with the general consensus that landscape is difficult to sell in microstock.

You have some nice deep blues and greens, and the composition is proper.  Look at all that copy space in the sky though - I think that is probably the one thing this image has going for it.

My guess is once you get a bunch more images on DT, the more marketable images will rise above this one in overall sales pretty quickly. But I wouldn't be surprised to see this one get a few sales now and then.

One problem though.  It looks like your horizon is crooked.  That cuts down on the marketability.  You might consider fixing it and uploading a replacement with a note to the reviewer.

Good job, and keep working at it!