Wonderful photograph. There are a few components to this photograph that are deserving of praise. Let’s start with the overall composition. This photograph abides by the rule of thirds by placing the line the river creates on the bottom 1/3 of the photograph. Not only that, but the tree to the right acts as a primary object and it’s placed perfectly at one of the intersecting points of the rule of thirds.
On a similar note, many nature photographs lack a main subject, however, the tree in your foreground acts as a “stopper” that allows the eye to rest when it’s not exploring the rest of the photograph. Without a stopper it’s too easy for the eye to wander in and then quickly out of a photograph.
Next, your color control is brilliant. You’ve used predominantly analogous colors to create a soothing and smooth transition between colors. Similarly, you’ve managed to find a great tonal range in this shot. You’ve captured deep dark tones as well as incredibly brilliant white tones. While this is a “must” for black and white photograph, have a wide tonal range also helps with color photography. Great work! I look forward to seeing your next assignment!