So a question I'll have to ask myself is how do I get the subject and the location to interact? Why is the subject in this particular location? What is my subject: human in nature, a fairy in his or her element, a child at play, etc.? Because I focus on emotion, I need to create an emotional connection between a person and the environment.
When setting up body language, keep in mind the message you are conveying. Is the subject lonely, happy, carefree, depressed, enraged, etc.? Then, think about which body position conveys what message. For example, crossed arms over the body closes off communication to the viewer. The subject wants to be left alone...but have them lean in toward the viewer and you've added a hint of interest, but cautious interest because of the crossed arms.
Another aspect of incorporating body language with an environment is that it becomes more story-telling and less about an emotional portrait. What is the story that you are trying to tell your viewer? Yet, leave it obscure enough for the viewer to incorporate their own storytelling into the image. By keeping the image mysterious, you engage the viewer.
The following images tell stories: