It's a lovely picture. You would try to reduce the sharpen effect: I believe that is what is causing this bright area around the branches and birds. Sorry for my comment if this effect was intended.
I understand what you are trying to do with this, but it is way out of focus and over enlarged or something. Did you take this section out of the larger image?
Not as strong a statement about negative space as I would have expected/liked for this challenge. The colors are good. The focus across the image is hazy which makes it hard to direct your eyes anywhere in particular.