This is an interesting subject, but in really difficult light. Possibly morning or evening light would have been better?
The sky in the background, and the water behind is a little over exposed, which will be because you were trying to keep the detail in the front of the boot. The bright sky and water keeps my eye away from the focus of the photo, the boots. Even the sunlight on the rock in the foreground is a little distracting.
You've got down to the boots level, and created an image rather than just taking the boot as you saw them from eye level which is great, but I think because you've got them smack dab in the middle of the frame it's not as interesting as it might have been.
A possible fix to the light would be to use fill-flash, or use a white bit of paper or cardboard to reflect some sunlight onto the 'front' of the boot. If you've got one a fancy fold up reflector would be good, but white paper does just as well. This would allow you to keep the detail in the boot without over exposing the background elements as much.
You're on the right track with this shot, you've focused right in on the object you intended, and your focus and DOF are good..
Why is a shoe sitting in a river with no foot?
The water behind the shoe is over exposed, and the shadows have no details. When taking a photo of a black object with a bright back ground you need to meter your camera (hold the shutter button half way down) in the darkest area so there is still enough details present in the dark area. Would have ben easier though to have just roated the boat around and not taken the photo with the sun glare behind the boot.