Doesn't look at all happy to be where she is, and before this shot she is totally bored. When working with a model you need to pay attention to their reaction, because it can either make, or in this example, break your picture.
I like all the textures but the bikini is really saggy and i think it takes away from the impact/sex appeal of the photo. Also, your placement in the frame is not as efective as I think it could be. The diagonal line of the waterfall could have been used to guide the viewers eye to the model, but intead it all kind of mushes together because she is right in the middle. nice lighting, you really brought out the softness in her skin